Pseudomonas aeruginosa

J Bacteriol, 1992 Feb, 174(4), 1248 - 57
Characterization of In0 of Pseudomonas aeruginosa plasmid pVS1, an ancestor of integrons of multiresistance plasmids and transposons of gram-negative bacteria; Bissonnette L et al.; Many multiresistance plasmids and transposons of gram-negative bacteria carry related DNA elements that appear to have evolved from a common ancestor by site-specific integration of discrete cassettes containing antibiotic resistance genes or sequences of unknown function . The site of integration is flanked by conserved segments coding for an integraselike protein and for sulfonamide resistance, respectively . These segments, together with the antibiotic resistance genes between them, have been termed integrons (H . W . Stokes and R . M . Hall, Mol . Microbiol . 3:1669-1683, 1989) . We report here the characterization of an integron, In0, from Pseudomonas aeruginosa plasmid pVS1, which has an unoccupied integration site and hence may be an ancestor of more complex integrons . Codon usage of the integrase (int) and sulfonamide resistance (sul1) genes carried by this integron suggests a common origin . This contrasts with the codon usage of other antibiotic resistance genes that were presumably integrated later as cassettes during the evolution and spread of these DNA elements . We propose evolutionary schemes for (i) the genesis of the integrons by the site-specific integration of antibiotic resistance genes and (ii) the evolution of the integrons of multiresistance plasmids and transposons, in relation to the evolution of transposons related to Tn21.

J Biol Chem, 1992 Jan 15, 267(2), 990 - 6
Characterization of guanosine diphospho-D-mannose dehydrogenase from Pseudomonas aeruginosa . Structural analysis by limited proteolysis; Roychoudhury S et al.; Alginate is believed to be a major virulence factor in the pathogenicity of Pseudomonas aeruginosa in the lungs of patients suffering from cystic fibrosis . Guanosine diphospho-D-mannose dehydrogenase (GDPmannose dehydrogenase, EC 1.1.1.132) is a key enzyme in the alginate biosynthetic pathway which catalyzes the oxidation of guanosine diphospho-D-mannose (GDP-D-mannose) to GDP-D-mannuronic acid . In this paper, we report the structural analysis of GMD by limited proteolysis using three different proteases, trypsin, submaxillary Arg-C protease, and chymotrypsin . Treatment of GMD with these proteases indicated that the amino-terminal part of this enzyme may fold into a structural domain with an apparent molecular mass of 25-26 kDa . Multiple proteolytic cleavage sites existed at the carboxyl-terminal end of this domain, indicating that this segment may represent an exposed region of the protein . Initial proteolysis also generated a carboxyl-terminal fragment with an apparent molecular mass of 16-17 kDa which was further digested into smaller fragments by trypsin and chymotrypsin . The proteolytic cleavage sites were localized by partial amino-terminal sequencing of the peptide fragments . Arg-295 was identified as the initial cleavage site for trypsin and Tyr-278 for chymotrypsin . Catalytic activity of GMD was totally abolished by the initial cleavage . However, binding of the substrate, GDP-D-mannose, increased stability toward proteolysis and inhibited the loss of enzyme activity . GMP and GDP (guanosine 5'-mono- and diphosphates) also blocked the initial cleavage, but NAD and mannose showed no effect . These results suggest that binding of the guanosine moiety at the catalytic site of GMD may induce a conformational change that reduces the accessibility of the cleavage sites to proteases . Binding of {14C}GDP-D-mannose to the amino-terminal domain was not affected by the removal of the carboxyl-terminal 16-kDa fragment . Furthermore, photoaffinity labeling of GMD with {32P}arylazido-beta-alanine-NAD followed by proteolysis demonstrated that the radioactive NAD was covalently linked to the amino-terminal domain . These observations imply that the amino-terminal domain (25-26 kDa) contains both the substrate and cofactor binding sites . However, the carboxyl-terminal fragment (16-17 kDa) may possess amino acid residues essential for catalysis . Thus, proteolysis had little effect on substrate binding, but totally eliminated catalysis . These biochemical data are in complete agreement with amino acid sequence analysis for the existence of substrate and cofactor sites of GMD . A linear peptide map of GMD was constructed for future structure/functional studies.

Med J Aust, 1992 Jan 6, 156(1), 20 - 4
Resistance to ciprofloxacin of respiratory pathogens in patients with cystic fibrosis; Dostal RE et al.; OBJECTIVE: To determine the incidence of resistance to ciprofloxacin in respiratory pathogens isolated from patients with cystic fibrosis (CF) compared with that of isolates from patients without CF . The hypothesis was that repeated exposure of these respiratory pathogens to ciprofloxacin would reduce their sensitivity . DESIGN: Isolates of Pseudomonas aeruginosa and Staphylococcus aureus were obtained prospectively from sputa of patients with CF, as part of their routine care . The sensitivities of these isolates to ciprofloxacin were determined by standard agar dilution techniques . SETTING AND PATIENTS: The study was carried out in patients who attended the outpatient clinic or were treated as inpatients of a tertiary referral hospital . Sputa were obtained from 71 patients with CF (age range, 2-31 years) and isolates of P . aeruginosa and S . aureus were compared with those from 54 hospital patients who did not have CF . OUTCOME MEASURES: Sensitivities to ciprofloxacin, expressed as the minimal concentrations required to inhibit growth of the organisms (MIC), were used to make comparisons between different isolates and the same isolates within patients at different times . RESULTS: A higher incidence of ciprofloxacin resistance was displayed by isolates of P . aeruginosa from CF patients who had been previously prescribed ciprofloxacin (MIC50 of 2.0 mg/L and 4.0 mg/L for mucoid and non-mucoid strains respectively) . The MIC of individual organisms tended to rise after a course of ciprofloxacin had been given to their host . A much lower incidence of resistance was displayed by isolates of P . aeruginosa from patients without CF (MIC50, 0.25 mg/L) . Similarly, S . aureus isolates from patients with CF exhibited greater resistance to ciprofloxacin (MIC50, 32 mg/L) than isolates from other patients (MIC50, 0.75 mg/L) . CONCLUSION: The resistance of P . aeruginosa appears to be related to ciprofloxacin exposure, so further development of resistance may be diminished by restricting the frequency of ciprofloxacin administration to individual patients.

Cornell Vet, 1992 Jan, 82(1), 69 - 77
Serum concentrations of cefepime (BMY-28142), a broad-spectrum cephalosporin, in dogs; Stampley AR et al.; Serum concentrations of cefepime (BMY-28142) were determined for four dosing regimes, 10 mg/kg or 20 mg/kg, given as single subcutaneous (SC) or intramuscular injections (IM) to dogs . Serial serum samples were analyzed for the presence of cefepime by high-performance liquid chromatography . In experiment 1, the overall mean (+/- SEM) serum concentration (for a 12-hour period) after a dose of 20 mg/kg for SC and IM routes (4.9 +/- 0.74 micrograms/ml and 5.5 +/- 0.63 micrograms/ml, respectively) was twice that for the 10 mg/kg dose given either SC or IM (2.2 +/- 0.31 micrograms/ml and 2.8 +/- 0.47 micrograms/ml, respectively) . There was no significant difference (p greater than 0.05) in mean serum concentrations for SC and IM routes of administration at the same dosage . In subsequent experiments, 5 doses of cefepime (20 mg/kg) were administered IM at 12-hour (experiment 2) or 24-hour (experiment 3) intervals . The mean (+/- SEM) peak serum concentration was 12.1 +/- 1.59 micrograms/ml, 2 hours after the 2nd injection in experiment 2 . In experiment 3, the mean (+/- SEM) peak serum concentration was 10.9 +/- 1.34 micrograms/ml, 4 hours after the 1st injection . Mean trough concentrations in experiment 2 were greater than or equal to 0.5 microgram/ml and less than or equal to 0.5 in experiment 3 . Multiple IM doses produced transient edema at the injection site and mild lameness in all dogs . Cefepime was highly active against single canine isolates of Staphylococcus intermedius, Pseudomonas aeruginosa and Escherichia coli, with minimum inhibitory concentrations of 0.125 microgram/ml, 1 microgram/ml and 0.3 microgram/ml, respectively.

Mol Microbiol, 1992 Jan, 6(1), 59 - 66
Pseudomonas aeruginosa AlgB, which modulates the expression of alginate, is a member of the NtrC subclass of prokaryotic regulators; Goldberg JB et al.; The Pseudomonas aeruginosa exopolysaccharide alginate is an important virulence factor in chronic pulmonary infections of cystic fibrosis patients . We determined the nucleotide sequence of the gene, algB, which regulates the level of exopolysaccharide produced by mucoid P . aeruginosa . The predicted amino acid sequence of AlgB revealed a high degree of similarity to the regulatory proteins in the NtrC subclass of 'two-component regulatory systems' . AlgB expression in Escherichia coli minicells showed a molecular weight of approximately 50,000 Da, comparable to that of the inferred amino acid sequence (49,318 Da) . We show that algB is transcriptionally active in mucoid strains of P . aeruginosa and regulates the expression of the alginate biosynthetic gene, algD, thereby resulting in increased expression of alginate in mucoid P . aeruginosa.

Cancer Invest, 1992, 10(1), 43 - 59
Pseudomonas aeruginosa infection in cancer patients; Rolston KV et al.; Pseudomonas aeruginosa is an important cause of infection in immunosuppressed patients, particularly those with cancer . However, it is being recognized with greater frequency in patients who appear to be immunocompetent . Changes in modern lifestyles have led to the appearance of some new manifestations of pseudomonas infection including corneal ulceration and keratitis associated with contact lenses, and hot-tub- or whirlpool-associated folliculitis . These represent additional hazards to patients with cancer . Many studies, both in animals and humans, have contributed to our knowledge of the pathogenesis, immunology, treatment, and prevention of pseudomonas infections . Although the aminoglycosides represented a significant step forward in the treatment of these infections, of greater importance was the discovery of the antipseudomonal penicillins . These antibiotics are more effective than the aminoglycosides in neutropenic patients, who are especially susceptible to pseudomonal infections . The older antipseudomonal penicillins (carbenicillin, tircarcillin) have largely been replaced by newer ones (mezlocillin, azlocillin, pipercillin) which are more potent in vitro against P . aeruginosa . Although the accepted therapeutic practice has been to utilize a penicillin in combination with an aminoglycoside, the introduction of newer beta lactam agents and fluoroquinolones with antipseudomonal properties offers the possibility of other approaches to combination therapy . These include the combination of a penicillin or a cephalosporin or the combination of a quinolone with an aminoglycoside or a betalactam antibiotic . However, the development of newer antimicrobial agents is not likely to be a lasting solution to the problem of pseudomonas infections . Since pseudomonas infection often progresses rapidly, optimal results will always depend upon the prompt initiation of appropriate therapy in febrile patients, particularly those who are at high risk . The use of granulocyte transfusions has proved to be of limited benefit . Early data with the use of monoclonal antibodies is promising, and the results of large-scale trials are eagerly awaited . It is hoped that continuing investigation of pseudomonas vaccines will lead to the discovery of effective prophylaxis for highly susceptible patients . It is also hoped that with the availability of GM-CSF it will become possible to reduce the period of risk for serious infections . Finally, a reduction in the frequency of microbiologically proven P . aeruginosa infections in cancer patients should not lead to the assumption that these organisms do not constitute a problem in such patients anymore . The use of prophylactic antibiotics and prompt empiric antibiotic coverage for therapy has resulted in this decline . Cultures are therefore unlikely to be positive with the same frequency as they were before antimicrobial prophylaxis and empiric antibiotic therapy became standard practice.(ABSTRACT TRUNCATED AT 400 WORDS)

Plant Mol Biol, 1992 Jan, 18(2), 247 - 58
Arrest of embryo development in Brassica napus mediated by modified Pseudomonas aeruginosa exotoxin A; Koning A et al.; Intracellularly expressed cytotoxins are useful tools both to study the action of plant regulatory sequences in transgenic plants and to modify plant phenotype . We have engineered a low mammalian toxicity derivative of Pseudomonas aeruginosa exotoxin A for intracellular expression in plant cells by fusing the ADP ribosylating domain of the exotoxin gene to plant regulatory sequences . The efficacy of exotoxin A on plant cells was demonstrated by transient expression of the modified exotoxin gene in tobacco protoplasts: the exotoxin gene inhibited the expression of a co-electroporated beta-glucuronidase gene . An exotoxin with an introduced frameshift mutation was also effective at inhibiting beta-glucuronidase expression in the transient assay; the activity of the frameshifted gene was presumably a result of frameshifting during translation or initiation of translation at a codon other than AUG . When fused to napin regulatory sequences, the exotoxin gene specifically arrested embryo development in the seeds of transgenic Brassica napus plants concomitant with the onset of napin expression . The napin/exotoxin chimeric gene did not have the same pattern of expression in tobacco as in B . napus; in addition to exhibiting an inhibition of seed development, the transgenic tobacco plants were male-sterile.

J Bacteriol, 1992 Jan, 174(1), 327 - 30
Localization of alg, opr, phn, pho, 4.5S RNA, 6S RNA, tox, trp, and xcp genes, rrn operons, and the chromosomal origin on the physical genome map of Pseudomonas aeruginosa PAO; Romling U et al.; The genes encoding the rrn operons, the 4.5S and 6S RNAs, elements of protein secretion, and outer membrane proteins F and I, and regulatory as well as structural genes for exotoxin A, alkaline phosphatase, and alginate and tryptophan biosynthesis, were assigned on the SpeI/DpnI macrorestriction map of the Pseudomonas aeruginosa PAO chromosome . The zero point of the map was relocated to the chromosomal origin of replication.

Chest, 1992 Jan, 101(1), 194 - 8
Recurrent Pseudomonas aeruginosa pneumonia in an intensive care unit; Silver DR et al.; We reviewed the records of all patients in the intensive care unit (ICU) who had Pseudomonas aeruginosa pneumonia over a 2.5-year period . Of patients with P aeruginosa pneumonia, 20 of 34 survived the initial episode of pneumonia . Ten of these 20 developed recurrence . In the nonrecurrent group, nine of ten survived hospitalization, compared to only four of ten in the recurrent group . Comparing the recurrent to the nonrecurrent group, factors associated with recurrence were the APACHE 2 score (12.3 +/- 2.7 vs 8.6 +/- 4.2 {p less than 0.03}), APS score (7.0 +/- 3.5 vs 2.7 +/- 2.1 {p less than 0.01}), and chronic pulmonary disease (8/10 vs 2/10 {p less than 0.05}) . The recurrent P aeruginosa group was younger (63 +/- 10 vs 74 +/- 11 years old {p less than 0.03}) and spent more time receiving mechanical ventilation (95 +/- 64 vs 26 +/- 36 days {p less than 0.01}), in the ICU (101 +/- 61 vs 33 +/- 35 days {p less than 0.01}), and in the hospital (144 +/- 77 vs 84 +/- 32 days {p less than 0.03}) . Although not statistically significant, in the recurrent group, eight of ten patients had tracheostomy and seven of ten had COPD, vs three of ten and two of ten, respectively, in the nonrecurrent group . Recurrent P aeruginosa pneumonia in the ICU is associated with increased morbidity and mortality and does not appear to be related to the adequacy of antibiotic treatment . Chronic lung disease appears to predispose patients to recurrent P aeruginosa pneumonia.

Am J Respir Cell Mol Biol, 1992 Jan, 6(1), 116 - 22
Release of mucus glycoconjugates by Pseudomonas aeruginosa rhamnolipid into feline trachea in vivo and human bronchus in vitro; Somerville M et al.; Pseudomonas aeruginosa colonizes the lower respiratory tracts of patients with severe bronchiectasis, including cystic fibrosis, a condition associated with increased airway mucus output . We have shown that an extract containing chloroform-soluble extracellular products of P . aeruginosa releases glycoconjugates into the cat trachea in vivo . This activity was not related to pyocyanin, a major component of the extract, but was associated with the rhamnolipids . Purified monorhamnolipid (100 micrograms/ml) released radiolabeled and periodic acid-Schiff (PAS)-reactive glycoconjugates (delta 3H = +490 +/- 70%, delta 35S = +170 +/- 40%, delta PAS = +8.6 +/- 1.7 micrograms/min; n = 6, P less than 0.02 for each) . Dirhamnolipid (200 micrograms/ml) was also effective (delta 3H = +640 +/- 70%, delta 35S = +130 +/- 20%, delta PAS = +9.3 +/- 1.5 micrograms/min; n = 6, P less than 0.02 for each) . Monorhamnolipid (100 micrograms/ml) also released 35S-labeled and PAS-reactive glycoconjugates from human bronchial tissue in vitro (delta 35S = +189 +/- 47%, delta PAS = +26.3 +/- 8.5 micrograms/min; n = 7, P less than 0.001 versus control tissues in which no stimulus was given) . The cat tracheal glycoconjugates released by the rhamnolipids differed from those released by pilocarpine 50 microM, in having a higher 3H:35S ratio (P less than 0.001) . After gel chromatography on a Sepharose CL-4B column, the void volume fractions of the glycoconjugates also had different profiles in a cesium chloride density gradient . Those released by rhamnolipid banded at 1.62 g/ml, while those released by pilocarpine banded mainly at 1.50 g/ml, with some of the higher density material also present.(ABSTRACT TRUNCATED AT 250 WORDS)

Arch Otolaryngol Head Neck Surg, 1992 Jan, 118(1), 94 - 6
Necrotizing 'malignant' external otitis caused by Staphylococcus epidermidis; Barrow HN et al.; Necrotizing "malignant" external otitis is a life-threatening skull base infection that originates in the external auditory canal and is characterized by otalgia and purulent aural discharge with external auditory canal cellulitis and granulation . Necrotizing external otitis, seen almost exclusively in elderly diabetics, is almost always caused by Pseudomonas aeruginosa . To our knowledge, there have been only six nonpseudomonal cases reported to date . We describe a 70-year-old diabetic man with necrotizing external otitis caused by Staphylococcus epidermidis, confirmed by serial cultures . This case was characterized by otalgia, purulent otorrhea, preauricular swelling, bony external auditory canal erosion, and a conductive hearing loss . Despite prolonged intravenous antistaphylococcal antibiotic therapy and frequent local debridement, the patient's symptoms never completely resolved . As demonstrated by the treatment failure, S epidermidis necrotizing external otitis, may represent a more refractory form of this already virulent disease process . We believe this to be the first reported case of necrotizing external malignant otitis caused by S epidermidis.

J Infect Dis, 1992 Jan, 165(1), 26 - 33
Human monoclonal antibodies to glycolipid A that exhibit complement species-specific effector functions; Winkelhake JL et al.; Two human IgM monoclonal anti-glycolipid A antibodies (MAbs) were evaluated for their abilities to bind to various endotoxins and pathogenic gram-negative bacteria and to activate complement pathways, thereby accomplishing bactericidal and opsonic effector functions . Both MAbs cross-reacted with glycolipid A mutant lipopolysaccharides from rough colony-forming gram-negative bacteria and with selected endotoxins from smooth colony-forming bacteria . However, MAb 10235 bound to all clinical isolates of Escherichia coli and Klebsiella pneumoniae tested but only very weakly to Pseudomonas aeruginosa, whereas MAb 10058 bound to all three genera . Several strains of serum-insensitive organisms were selected for evaluation of antigen-specific, complement-mediated effector functions for the two MAbs . Assessment of bactericidal and opsonic activities showed that neither MAb was able to activate complement from nonprimate species (mouse, rat, rabbit, guinea pig, or sheep) . However, both MAbs were highly effective in using primate sources of serum complement to mediate these effector functions.

Intensive Care Med, 1992, 18 Suppl 1, S35 - 8
Immunological perspectives in prevention and treatment of nosocomial pneumonia; Pennington JE; The high mortality associated with current therapeutic approaches to nosocomial pneumonia has motivated consideration of newer immunologic approaches to prevention or therapy of this infection . Serotype specific vaccines, hyperimmune immunoglobulins, and monoclonal antibodies have been developed for certain problematic pathogens . Pseudomonas aeruginosa has been the major focus of this approach, and trials of hyperimmune anti-Ps . aeruginosa globulins for treatment of pneumonia are underway . Broad-spectrum, anti-lipopolysaccharide antibody preparations have also been employed for prophylaxis of nosocomial pneumonia, but to date these trials have not been successful . Finally, anticytokine antibody therapy to reduce infection-initiated inflammatory lung damage is under consideration.

Proc Natl Sci Counc Repub China B, 1992 Jan, 16(1), 10 - 6
Removal of copper ion by Pseudomonas spp; Chao WL; Copper-resistant Pseudomonas sp . 41Y, Pseudomonas pseudomallei 13-1 and Pseudomonas aeruginosa 7 were used in the present study . When the latter two organisms were added to copper-containing 1/3 strength Tryptic Soy Broth, more than 99.5% of the copper ion was removed from the medium within 24 h . If copper solution was added to hog waste slurry, a reduction in the copper ion concentration could be detected only when the added bacteria started to grow in it, whereas in a mineral medium supplemented with glycerol-2-phosphate, both bacteria could remove about 50% of the copper ion from the medium within 24 h . When cell suspension of Pseudomonas sp . 41Y was autoclaved, no copper ion removal was observed . Different incubation temperatures, including 30 degrees C, 37 degrees C and 45 degrees C, had no effect on the percent of copper ion removed by both Pseudomonas sp . 41Y and P . pseudomallei 13-1 . On the other hand, if the pH value of the solution was lowered from 8.2 to 6.0, there was a drastic decrease in copper removal . A similar reduction of copper ion removal ability was also observed with the addition of lead ion . When cells of Pseudomonas sp . 41Y were embedded in sodium alginate, there was a decrease in its ability to remove copper ion as compared to the free-living cells.

J Hyg Epidemiol Microbiol Immunol, 1992, 36(1), 105 - 10
Biological carrier improves passive protection of mice against Pseudomonas aeruginosa infection; Sourek J et al.; In a model experiment, the use of specific hyperimmune globulins (SHG) alone failed to protect mice against infection with homologous and heterologous P . aeruginosa serotypes . However, the therapeutic potential of SHG dramatically improved after its conjugation with A1(OH)3, used as a biological carrier . The binding of SHG to this carrier proved to be the most effective and stable combination in the treatment of acute pseudomonad infections in mice.

Chemotherapy, 1992, 38(1), 21 - 7
Bactericidal activities of ofloxacin and its optically active isomer (DR-3355) on non-growing cells of Escherichia coli and Pseudomonas aeruginosa; Tanaka M et al.; In this paper the bactericidal activities of ofloxacin and its optically active derivative, DR-3355, against non-growing cells of Escherichia coli and Pseudomonas aeruginosa are described . E . coli and P . aeruginosa were killed rapidly by ofloxacin and DR-3355 . After treatment with these quinolones, the resting cells of E . coli and P . aeruginosa became plasmolyzed, with apparent cytoplasmic shrinkage without filamentation . Membrane-bound intracellular vacuoles and disruption of the cell envelope were also observed, resulting in extrusion of the cytoplasmic contents . These results indicate that non-growing cells of E . coli and P . aeruginosa were susceptible to ofloxacin and DR-3355, as were logarithmically growing cells.

Ophthalmic Res, 1992, 24(1), 32 - 9
Distribution and kinetics of the inflammatory cell response to ocular challenge with Pseudomonas aeruginosa in susceptible versus resistant mice; Hazlett LD et al.; This study examined and characterized the distribution and kinetics of the inflammatory cell response to pseudomonas ocular challenge in susceptible C57BL/6J and resistant DBA/2J mice . Initially, in the cornea, the number of neutrophilic leukocytes (PMNs), macrophages/monocytes or lymphocytes was 2-2.5 times greater in resistant versus susceptible mice . The peak cellular response in the cornea was also greater in resistant than in susceptible animals . Further, resistant mice, when compared with susceptible mice, had a shorter duration of inflammatory cells as well as bacteria in the cornea . These data were similar for the cell infiltrate in the anterior chamber, with the exception that PMNs were initially greater in number in C57BL/6J than in DBA/2J mice . Collectively these data suggest that susceptible mice are, in general, cellularly hyporesponsive to pseudomonas ocular challenge when compared with resistant animals . This, together with persistence of inflammatory cells and bacteria in the cornea of susceptible animals, may contribute to their failure to restore corneal clarity following pseudomonas ocular challenge.

Chemotherapy, 1992, 38(2), 82 - 91
Lipopolysaccharide alterations responsible for combined quinolone and beta-lactam resistance in Pseudomonas aeruginosa; Leying HJ et al.; Resistant variants of three clinical Pseudomonas aeruginosa isolates were obtained in the presence of aztreonam . The variants exhibited a four- to eightfold increase in the minimal inhibitory concentrations to beta-lactam antibiotics (except imipenem) to quinolones, such as norfloxacin and fleroxacin, chloramphenicol and tetracycline, but not to gentamicin and polymyxin B . beta-Lactamase production was barely detectable in both wild-type strains and the resistant clones . Only ampicillin, cefoxitin and imipenem increased the production of beta-lactamase, whereas various other beta-lactams did not . Penicillin-binding proteins remained unchanged in the aztreonam-resistant clones . The analysis of the outer membrane proteins did not reveal differences in the outer membrane proteins between the wild-type strains and the aztreonam-resistant clones . Two of the three antibiotic-resistant isogenic clones contained less lipopolysaccharides (LPSs) than their corresponding wild-type strains . Moreover, it could be demonstrated that the ratio of 2-keto-3-deoxy octonate to carbohydrate of the LPS changed in any case between the wild-type strains and the aztreonam-resistant clones . These alterations were accompanied by a decrease in surface hydrophobicity of the resistant clones as compared to the wild-type strains . Therefore, quantitative as well as qualitative alterations in the LPS may provide an explanation for the resistant phenotype observed.

Antimicrob Agents Chemother, 1992 Jan, 36(1), 71 - 6
High-level beta-lactamase activity in sputum samples from cystic fibrosis patients during antipseudomonal treatment; Giwercman B et al.; The in vivo activity and source of beta-lactamase in sputum samples from 43 patients with cystic fibrosis (CF) during a 2-week antipseudomonal treatment were studied . A colorimetric method, based on the conversion of nitrocefin, was used for quantitation of the sputum beta-lactamase activity . beta-Lactamases in sputum were characterized by isoelectric focusing and inhibition profile and were compared with the beta-lactamases extracted from Pseudomonas aeruginosa isolated from the paired sputum samples . We found that the beta-lactamase activity increased to high levels in sputum from patients with CF during the course of piperacillin, ceftazidime, cefsulodin, or imipenem therapy . Aztreonam therapy lead to opposite results because the beta-lactamase activity decreased and aztreonam was able to mask beta-lactamase activity by acting as an inhibitor . All sputum beta-lactamases displayed characteristics indicative of a class I enzyme, identical to the beta-lactamases extracted from P . aeruginosa . The presence of beta-lactamase at such levels could lead to in vivo inactivation of beta-lactam antibiotics . This study supports the hypothesis that beta-lactamase production is an important in vivo resistance mechanism in P . aeruginosa-infected patients with CF.

Minerva Anestesiol, 1992 Jan-Feb, 58(1-2), 1 - 5
{Evaluation of bacterial resistance to pefloxacine after prolonged use in resuscitation}; Malacarne P et al.; In an overall of the value of an antibiotic it is important to take into account the onset of bacterial resistance in addition to its immediate clinical effects since the former can render an otherwise efficacious antibiotic obsolete within a short space of time . We studied two groups of intubated patients with pneumonia infections during two different periods in 1990: January-June and October-December; each patient was treated with pefloxacin 400 mg twice a day i.v . for 6 days on the basis of an antibiogram carried out on tracheobronchial secretion; at the end of that period patients were clinically evaluated and a second bacteriological test was performed . It was found that the percentage of pefloxacin-resistant bacterial strains did not increase significantly after this antibiotic had been used for a year for pneumonia infections (from 27.5% to 33%) . The appearance of bacterial resistance at the six-day treatment cycle was similar in both groups (19% and 22%) . Of all the bacterial strains, Pseudomonas aeruginosa showed the greatest tendency to become resistant.

Arzneimittelforschung, 1992 Jan, 42(1), 70 - 2
Synthesis and antipseudomonal activities of some ofloxacin esters as prodrugs; Ertan M et al.; Three new ofloxacin esters have been synthesized as prodrug by the reaction of ofloxacin (CAS 82419-36-1) with chloromethylacetate, 1-chloroethylacetate and 1-chloroethylethylcarbonate in acetonitrile . The structures of the compounds have been elucidated by UV, IR, 1H-NMR, Mass spectra and elementary analysis . In vitro activities of these compounds against clinical isolates of various Pseudomonas aeruginosa species have been determined by microtiter tube dilution method, and octanol/water partition coefficients and pH dependent hydrolysis rates have been investigated in comparison with ofloxacin.

Eur Surg Res, 1992, 24(2), 69 - 76
Effect of polymyxin B on intestinal bacterial translocation in Pseudomonas aeruginosa wound-colonized burned mice; Dijkstra HM et al.; Bacterial translocation (BT) from the gastrointestinal tract has been proposed to play a role in the pathogenesis of septic complications in severely burned patients . In a burn model the effect of a subtherapeutic dose of polymyxin B-sulfate (PB) at BT was examined in Escherichia coli-monoassociated mice with Pseudomonas aeruginosa-inoculated burn wounds . The BT incidence and number of translocating microorganisms to the spleen (p less than 0.01), liver (p less than 0.01), lung (p less than 0.05) and heart (p less than 0.05) were diminished significantly in the PB-treated versus the untreated group . Endotoxin in plasma was detectable in one of the 16 PB-treated versus 6 of the 17 control mice (p less than 0.05) . The relation of Pseudomonas burn wound inoculation, BT, endotoxin and the endotoxin-neutralizing properties of PB will be discussed.

Diagn Microbiol Infect Dis, 1992 Jan, 15(1), 73 - 80
New insights into the activity of third-generation cephalosporins against pneumonia-causing bacteria; Jones RN et al.; Over 300 isolates representing all pathogens causing greater than or equal to 4% of nosocomial or outpatient pneumonias were tested against currently used third-generation cephalosporins (cefotaxime, desacetylcefotaxime, ceftriaxone, ceftazidime, cefoperazone, and ceftizoxime) to determine differences in activity and effects of physiologic host and pharmacokinetic properties . Prevalent drug resistances were represented and tests were performed by reference methods of the National Committee for Clinical Laboratory Standards . Spectrums and potency of cefotaxime, desacetylcefotaxime, ceftriaxone, and ceftizoxime were most similar, but cefotaxime plus desacetylcefotaxime at in vivo ratios increased the cefotaxime spectrum (anaerobes and Pseudomonas) and potency . Ceftizoxime was least active because of current reduced activity against some Staphylococcus spp . and Pseudomonas aeruginosa . Ceftriaxone potency was adversely affected (greater than or equal to 4-fold decrease) by serum protein binding, thus reducing its susceptibility spectrum for pathogens with greater than or equal to 4 micrograms/ml minimum inhibitory concentrations (MICs) and a 10.6% reduced spectrum overall . Ceftazidime provided poorest coverage against the significant and clinically increasing Gram-positive cocci and did not significantly inhibit aspiration pneumonia causing anaerobic strains . Ceftazidime and cefoperazone were more active against pseudomonas, but they were most labile to newer extended-spectrum beta-lactamases . On empiric balance, the third-generation cephalosporins continue to provide the best therapeutic spectrum, particularly those favorably influenced by host factors (proteins and metabolism) . These third-generation cephalosporin differences become more important since some agents (ceftazidime) have readily selected type-I enzyme mutants among intensive-care-unit respiratory tract pathogens at our institution . Cost containment will also influence drug choices for some third-generation cephalosporins, usually favoring the earliest introduced compounds such as cefotaxime.

Mikrobiyol Bul, 1992 Jan, 26(1), 17 - 25
{Pyocin typing of Pseudomonas aeruginosa strains isolated from various sources}; Kantarci G; In our study, 103 strains of P.aeruginosa from various clinical specimens were typed by pyocin typing method with 13 indicator strains . As a result of pyocin typing, 18 different pyocin type were detected from 81 typable strains (78.6%), 22 of P.aeruginosa strains (21.3%) could not be typed because of the lack of their pyocin activity . On the other hand, 2 of typable P.aeruginosa strains were found to produce inhibition patterns that differed from standard inhibition patterns according to Govan and Gillies Method . Because of this reason, these two strains could not be classified . As a result of our study, it was observed that, strains that belong to pyocin type-1 were in majority . It was detected that, TSA Medium supplemented with 5% sheep blood can be used easily instead of TSA Medium, supplemented with 5% horse blood.

Exp Lung Res, 1992 Jan-Mar, 18(1), 155 - 71
Acute lung injury induced by Pseudomonas aeruginosa elastase in hamsters; Williams JC et al.; Human neutrophil elastase (HNE) is the predominant elastolytic enzyme in the sputum of cystic fibrosis (CF) patients . However, a variably small portion of the activity can be ascribed to Pseudomonas aeruginosa elastase (PaE) . The purpose of these studies was to evaluate the activities of the two elastases in an in vivo model of acute lung injury (ALI) . The elastolytic activity of Pseudomonas aeruginosa elastase (MW = 39K) and human neutrophil elastase (MW = 33K) were also examined using insoluble bovine neck and lung elastin . The ability of hamster serum to inhibit elastinolysis by the two elastases was also examined . On a per milligram protein basis, PaE was the more potent elastase, regardless of substrate, and it preferentially hydrolyzed lung relative to neck elastin . PaE is poorly inhibited by hamster serum compared to HNE . In vivo, PaE is much more efficient than HNE in inducing an acute lung injury in hamsters . The duration of effects induced by doses of the two proteases that produce similar acute biological effects are essentially identical . The increases of lung weight and total lavagable WBCs persist for at least 7 days . All other parameters return to baseline between 3 and 5 days . The predominant cells in the lavage 1 and 2 days post insult are PMNs . By day 7, the predominant cell is the macrophage . These data suggest that even though PaE is a minor component of the elastolytic activity in CF patients, it may still contribute significantly to the pathology of the disease.

Clin Infect Dis, 1992 Jan, 14(1), 353 - 4
Treatment of endocarditis due to Pseudomonas aeruginosa with imipenem; Fichtenbaum CJ et al.; Therapy for endocarditis due to Pseudomonas aeruginosa is complicated by the emergence of resistance during therapy, lack of universally available synergistic antimicrobial agents, and unacceptably high morbidity and mortality rates . The authors report a case of aortic valve endocarditis due to P . aeruginosa in which resistance to piperacillin developed during combined therapy with tobramycin . Bacteriologic cure was obtained with a combination of imipenem/cilastatin and tobramycin . The authors review six other cases of P . aeruginosa endovascular infections treated with imipenem.

Cornea, 1992 Jan, 11(1), 47 - 52
Attachment of Pseudomonas to human-worn, disposable etafilcon A contact lenses; Boles SF et al.; After 7 days of continuous wear, Acuvue (Vistakon, Jacksonville, FL, U.S.A.; etafilcon A) lenses were soaked in a Pseudomonas aeruginosa suspension (1.4 x 10(8) cfu/ml) . New Acuvue lenses served as controls . A single strain of P aeruginosa harvested from a human corneal ulcer was used throughout the experiment . Lenses were examined by culture and scanning electron microscopy (SEM) . We found significantly greater (p less than 0.05) bacterial attachment to new Acuvue lenses {culture, 3.1 x 10(4) (+/- 0.82 x 10(4)) cfu/mm2; SEM, 2.6 x 10(4) (+/- 0.47 x 10(4)) bacteria/mm2} compared with those previously worn {culture, 1.0 x 10(4) (+/- 0.17 x 10(4)) cfu/mm2; SEM, 0.73 x 10(4) (+/- 0.21 x 10(4)) bacteria/mm2} . No statistical difference was found among the individuals . Our findings demonstrate that the biological coating resulting from 1 week of continuous contact lens wear restricts P . aeruginosa attachment to the Acuvue lens when comparing new and used lenses.

Microbiologica, 1992 Jan, 15(1), 65 - 9
beta-Lactamase Id of ceftazidime-resistant Pseudomonas aeruginosa strains; Michel-Briand Y et al.; 4.2% Pseudomonas aeruginosa strains isolated in our hospital were resistant to ceftazidime . The 174K strain was also resistant to azthreonam but susceptible to imipenem and was studied as representative of these strains . It produced a single beta-lactamase (pI 8.6) which had all the characteristics of the chromosomal beta-lactamase Id and was the only beta-lactamase present . This enzyme hydrolyses slowly ceftazidime and imipenem . It could be a factor of imipenem resistance if the antibiotic influx into the bacteria was decreased or if the beta-lactamase Id was synthesized at a high level.

Refract Corneal Surg, 1992 Jan-Feb, 8(1), 39 - 43
Keratotomy model of pseudomonas keratitis: gentamicin chemotherapy; Brockman EB et al.; BACKGROUND: Chemotherapy of bacterial keratitis requires frequent application of antibiotic drops . Collagen shields containing antibiotics could reduce the need for frequent antibiotic application . To determine the effect of gentamicin-containing collagen shields and gentamicin drops on Pseudomonas keratitis, a new keratotomy model of infection was employed . METHODS: Model--contact lenses (58% water content) presoaked in 1% bovine serum albumin and exposed to 10(8) colony forming units per mL of Pseudomonas aeruginosa strain 27853, were found to reproducibly retain 5.9 (log base 10) colony-forming units . Rabbit corneas were scarified centrally with two perpendicular intersecting diamond knife cuts (5 mm x 5 mm x 0.2 mm), and bacteria-impregnated contact lenses were positioned and held in place for 24 hours with partial tarsorrhaphies . Treatment--Fourteen hours after lens removal (38 hours after infection), corneas were treated for 8 hours with collagen shields hydrated in saline (control), or shields impregnated with 800 micrograms gentamicin during manufacture, or one drop every 30 minutes of fortified gentamicin drops (14 mg/mL) . The rabbits were killed and corneas collected for bacterial enumeration after 8 hours of treatment (46 hours after infection) . RESULTS: Model--Slit-lamp examination and microbiologic confirmation showed uniformity of keratitis in all eyes . Treatment--Corneas treated with saline (controls) contained 6.4 (log base 10) Pseudomonas . Corneas treated with gentamicin-impregnated collagen shields (total drug = 800 micrograms) and fortified gentamicin drops (total drug = 21 mg) showed a reduction in viable bacteria of 2 logs and 6 logs, respectively, relative to the control . CONCLUSIONS: In this new model of Pseudomonas keratitis, the amount of gentamicin introduced into collagen shields during manufacture effectively reduced bacterial growth in infected rabbit corneas . However, larger amounts of drug applied as fortified drops on a frequent dosing schedule were more effective by a factor of three . Treatment of keratitis with antibiotic-impregnated collagen shields may reduce the need for very frequent application of topical drops, but may be more effective with topical drop supplementation to increase the amount of drug available over the course of therapy.

J Antibiot (Tokyo), 1992 Jan, 45(1), 103 - 12
Synthesis and structure-activity relationships of a new series of cephalosporins, E1040 and related compounds; Sugiyama I et al.; The synthesis and in vitro antibacterial activity of a series of 7-{(Z)-2-aminoaryl-2-oxyiminoacetamido}-3-ammoniomethyl++ +-3-cephems are described . Variation of an oxyimino moiety with aminoaryl at the C-7 side chain and a quaternary ammonium moiety at the C-3 side chain were examined and structure-activity relationships were studied . E1040, the 3-(4-carbamoylquinuclidinio)methyl derivative of the 7-alpha-methoxyimino series of aminothiadiazolyl cephalosporins, exhibited excellent activity against both Gram-positive and Gram-negative bacteria, particularly against Pseudomonas aeruginosa, and possessed high stability to beta-lactamases.

J Laryngol Otol, 1992 Jan, 106(1), 5 - 6
Malignant external otitis: management policy; el-Silimy O et al.; Malignant external otitis is a progressive pseudomonal infection of the external auditory canal and adjacent structures . In the literature there is no unified policy regarding the management of malignant external otitis . The development of an effective nuclear scanning method and antibiotics active against Pseudomonas aeruginosa have helped in formulating our management policy . A review of four years personal experience with this condition is presented . All of our cases were cured from the disease with no fatality . Gallium citrate scans showed that antipseudomonal treatment should continue for up to three months.

J Heart Lung Transplant, 1992 Jan-Feb, 11(1 Pt 1), 160 - 3
Pseudoaneurysm of the aorta after heart-lung transplantation: diagnosis by color flow Doppler mapping; Balaji S et al.; Five months after heart-lung transplantation for treatment of end-stage cystic fibrosis, a 14-year-old girl had a swelling over the manubrium that was identified as a pseudoaneurysm at the aortic anastomotic site by means of cross-sectional echocardiography with color flow Doppler mapping . The diagnosis was confirmed at operation, despite which she died . Biopsy material taken during the operation revealed chronic sternal osteomyelitis caused by Pseudomonas aeruginosa . Disruption of the aortic anastomosis by infection may be a major complication of heart-lung transplantation for treatment of cystic fibrosis.

Appl Environ Microbiol, 1992 Jan, 58(1), 174 - 80
Production, purification, and properties of a lipase from a bacterium (Pseudomonas aeruginosa YS-7) capable of growing in water-restricted environments; Shabtai Y et al.; An extracellular lipase from the low-water-tolerant bacterium P . aeruginosa YS-7 was produced, purified, and characterized with respect to its functional properties in aqueous solutions and organic solvents . The enzyme was partially released from the cells during fermentation in defined medium with 5% (wt/vol) soybean oil . Approximately one-half of the total culture activity remained in solution after removal of cells . More than 95% of the activity was found in culture supernatant after mild detergent treatment (10 mM sodium deoxycholate) or after shifting the carbon source during the fermentation from triglyceride to a free fatty acid . The enzyme was recovered from an acetone precipitate of the whole culture and purified by hydrophobic interaction chromatography, yielding a preparation having a specific activity of about 1,300 mumol of fatty acid mg-1 h-1 . The lipase (molecular size, approximately 40 kDa) hydrolyzes a variety of fatty acid esters and has an optimum pH of about 7 . The enzyme retained its full activity at 20 to 55 degrees C, even after prolonged exposure (more than 30 days) to different concentrations of water-miscible organic solvents such as alcohols, glycols, pyridine, acetonitrile, dimethyl formamide, and dimethyl sulfoxide . The hydrolysis of 4-nitrophenyl laurate ester and of triglyceride emulsified in water was slightly accelerated with increasing concentrations of alcohols and glycols up to about 20% but was abolished with a further increase in alcohol concentration or in the presence of acetonitrile . In contrast, the rate of hydrolysis of these substrates in concentrated solutions of dimethyl formamide or dimethyl sulfoxide was markedly increased, by more than twofold and more than fivefold, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Thorax, 1992 Jan, 47(1), 6 - 13
Role of alginate in infection with mucoid Pseudomonas aeruginosa in cystic fibrosis; Pedersen SS et al.; BACKGROUND: Chronic bronchopulmonary infection with mucoid, alginate producing Pseudomonas aeruginosa occurs characteristically in patients with cystic fibrosis . Alginate may be a virulence factor for P aeruginosa infection in such patients . METHODS: Forced vital capacity (FVC), nutritional state and the antibody response to P aeruginosa were determined at regular intervals from three years before chronic P aeruginosa infection to 10 years afterwards in 73 patients with cystic fibrosis . All patients were treated intensively with antipseudomonal chemotherapy during the study period . RESULTS: FVC was reduced in all patients who subsequently developed P aeruginosa infection before they acquired the infection, indicating significant pre-existing lung damage when compared with patients who remained free of P aeruginosa . Lung function and nutritional state remained unchanged after 10 years of infection, except in the patients who died of P aeruginosa lung infection . The FVC and height and weight of patients infected with nonmucoid strains of P aeruginosa were similar to those of uninfected patients . Patients infected with mucoid strains had poorer lung function and nutritional state for the first five years after infection compared with patients with nonmucoid strains . Such infection was also associated with greater IgG and IgA antibody responses to P aeruginosa standard antigen compared with nonmucoid infection . Concentrations of antibody to alginate were similar in patients with non-mucoid and mucoid infection . Noticeably increased concentrations of IgA antibodies to P aeruginosa standard antigen were observed early after the onset of infection in patients who subsequently died . CONCLUSION: Alginate producing P aeruginosa infection is associated with a hyperimmune response and poor clinical condition, suggesting that alginate production is a virulence factor in such infections in patients with cystic fibrosis.

APMIS, 1992 Jan, 100(1), 87 - 90
Local IgA and IgG response to intratracheal immunization with Pseudomonas aeruginosa antigens; Johansen HK et al.; We have experimentally immunized rats intratracheally with sonicated Pseudomonas aeruginosa to develop a high antibody response systemically and locally . The systemic antibodies were measured by a standard enzyme-linked immunosorbent assay (ELISA) on serum samples, whereas the local antibodies were measured on eluates from paper discs containing saliva . High levels of IgA antibodies were elicited in saliva whereas only traces of IgG antibodies were detected; the opposite results were found in serum . The saliva disc method permits serial measurements from the same animal and therefore offers the possibility to follow post-immunization antibody responses.

Photochem Photobiol, 1992 Jan, 55(1), 89 - 96
Inactivation of gram-negative bacteria by photosensitized porphyrins; Nitzan Y et al.; Photosensitization of Escherichia coli and Pseudomonas aeruginosa cells by deuteroporphyrin (DP) is shown to be possible in the presence of the polycationic agent polymyxin nonapeptide (PMNP) . Previous studies established complete resistance of Gram-negative bacteria to the photodynamic effects of porphyrins . The present results show that combined treatment of E . coli or P . aeruginosa cultures with DP and PMNP inhibit cell growth and viability . No antibacterial activity of PMNP alone could be demonstrated and cell viability remained unchanged . Spectroscopically, PMNP was found to bind DP, a mechanism which probably assists its penetration into the cell's membranes . Insertion of DP into the cells was monitored by the characteristic fluorescence band of bound DP at 622 nm . Binding times were 5-40 min and the extent of binding increased with decreasing the pH from 8.5 to 6.5 . DP binding constants, as well as the concentrations of PMNP which were required for maximal effect on the various Gram-negative bacteria, were determined fluorometrically . By the treatment of DP, PMNP and light the growth of E . coli and P . aeruginosa cultures was stopped and the viability of the culture was dramatically reduced . Within 60 min of treatment the survival fraction of E . coli culture was 9 x 10(-6) and that of P . aeruginosa was 5.2 x 10(-4) . Electron microscopy depicted ultrastructural alterations in the Gram-negative cells treated by DP and PMNP . The completion of cell division was inhibited and the chromosomal domain was altered markedly.

Microbios, 1992, 70(283), 77 - 91
Bacterial uptake of 14C-chlorhexidine diacetate and 14C-benzyl alcohol and the influence of phenoxyethanol and azolectin: studies with gram-negative bacteria; Fitzgerald KA et al.; The uptake of 14C-chlorhexidine (14C-CHA) by Pseudomonas aeruginosa and smooth, rough and deep rough strains of Escherichia coli was very rapid with maximum uptake occurring within 20 s . Despite the rapid binding, the lethal action of CHA, although concentration-dependent, is comparatively slow and occurs in minutes rather than seconds . This indicates that the initial rapid binding is followed by a second slower action, responsible for the lethal effects of CHA . The lethal action could be accelerated, particularly at modest concentrations of CHA, by the simultaneous presence of phenoxyethanol (POE) or benzyl alcohol (BZA), although the magnitude of the effect was small . Both alcohols had little effect on the binding of 14C-CHA, which does not explain the enhanced bactericidal action of CHA . Uptake of 14C-benzyl alcohol (14C-BZA) by the same strains showed very different patterns with slower and time-related binding . CHA had a marked effect on BZA absorption but no direct link was established between binding patterns and cell death . The CHA neutraliser, azolectin, removed bound CHA (in the presence or absence of POE) very efficiently even at contact times of only 20 s.

Arch Toxicol, 1992, 66(3), 224 - 7
Cytotoxicity of mebendazole against established cell lines from the human, rat, and mouse liver; Higa F et al.; The direct cytotoxicity of mebendazole (MBZ) was investigated by using cell lines derived from human, mouse and rat liver . It was demonstrated that Chang liver cells (derived from human liver) were more sensitive to the cytotoxic effects of MBZ than the other two cell lines . Longer incubation of the cells with MBZ resulted in stronger toxicity, and the cytotoxicity was dependent on the MBZ concentration above a certain threshold value (0.25-0.50 mg/l in a 42-h culture) . Inhibition of the proliferation of Chang liver cells by MBZ was detected at a concentration of 0.008 mg/l, a lower concentration than that having a cytotoxic effect . The other two cell lines were less sensitive to the inhibitory effect of MBZ . Proliferation of human mononuclear cells following stimulation by phytohemagglutinin (PHA) was inhibited by MBZ, and this inhibition was more extensive than that of cells stimulated with whole formalin-treated Pseudomonas aeruginosa . It is suggested that dividing cells may be more sensitive to MBZ cytotoxicity . This anti-proliferative effect may be related to its clinically known side effects, such as hepatotoxicity and bone marrow suppression.

Folia Microbiol (Praha), 1992, 37(5), 360 - 4
Permeability factor, cytotoxicity and serotyping of Pseudomonas aeruginosa strains; Hostacka A et al.; We analyzed in detail the permeability and cytotoxic activity as well as the serotypes of 127 Pseudomonas aeruginosa strains . Sixty-seven strains were isolated from immunocompromised patients (51 from patients with tumors and 16 from patients after transplantation) and 60 strains were isolated from patient's ears . Culture filtrates of strains isolated from patients after transplantation were responsible for the highest part of permeability reactions corresponding to an intermediate toxin production (68.8%) (categories 2 and 3) and culture filtrates of strains isolated from patients with tumors caused the highest percentage of permeability reactions corresponding to a strong toxin production . Culture filtrates of strains isolated from ears of patients were responsible for the highest percentage of negative permeability reactions (15%) . With positive permeability reaction size (categories 2-6) increased also the percentage of cytotoxicity as well as the intensity of morphological changes on Vero cells after 1 and 2 d . We did not observe any relationship between a particular permeability reaction category and the most frequent serotypes (O4, O6) or nontypable strains of the tested groups.

Microbiol Immunol, 1992, 36(11), 1195 - 200
The patterns and transmissibility of antibiotic resistance among clinical strains of Pseudomonas aeruginosa; Palillo ES et al.; Four hundred and ninety-eight predominantly pyocin-type 10 clinical strains of Pseudomonas aeruginosa were analyzed for resistance to carbenicillin, cefoperazone, cefotaxime, ceftazidime, gentamicin, amikacin and netilmicin . Based on NCCLS-recommended MIC breakpoints, 245 strains were found to be resistant, of which 41.6% were resistant to carbenicillin, 38% to gentamicin, 37.8% to netilmicin, 26.3% to cefoperazone, 17.9% to cefotaxime, 0.6% to amikacin and none to ceftazidime . Quadruple resistance to carbenicillin, cefoperazone, gentamicin and netilmicin was the most frequent pattern observed . Resistance to older antibiotics (kanamycin, streptomycin and tetracycline) and to mercuric chloride were also common . Conjugation experiments suggested that self-transmissible and non-transmissible plasmids occurred in at least 66 strains.

Microbiol Immunol, 1992, 36(11), 1113 - 8
Co-existence of colonies with different serotypes and other biological characteristics in clinical isolates of Pseudomonas aeruginosa; Kobayashi I et al.; The biological characteristics of individual colonies of Pseudomonas aeruginosa from 138 specimens were investigated . Of these isolates, 90 (65.2%) formed colonies of similar appearance and morphology, and 48 (34.8%) formed colonies which differed either in appearance or morphology . The individual colonies of 138 isolates were tested for serotype . The former 90 isolates formed only the colonies with one kind of serotype, whereas 17 of the latter 48 isolates formed the colonies with more than one kind of serotype . All the 9 isolates tested also differed in other biochemical characteristics: acid productions from xylose, mannitol and maltose, urease production and gelatin liquefaction . beta-Lactamase activity was investigated in 7 isolates forming colonies with more than one serotype . There were no marked differences in beta-lactamase activity among the different colonies in 5 isolates but marked differences among those in the other 2 isolates.

Matrix Suppl, 1992, 1, 259 - 62
Inhibition of human skin fibroblast collagenase by phosphorus-containing peptides; Galardy RE et al.; Substitution of the phosphonamidate linkage (PO2-NH) for the peptide bond (CO-NH) in substrate-like sequences produces inhibitors of human skin fibroblast collagenase with Ki's far below Km for the native collagen substrate . Using a thiol ester substrate at pH 6.5, phthaloyl-GlyP-Ile-Trp-(S)NHCH-(Me)Ph, the phosphonamidate analog of phthaloyl-Gly-Ile-Trp-(S)NHCH(Me)Ph, has a Ki of 20 nM . Peptide phosphonamidates with amino acid sequences extended further to the right or the left of the Gly-Ile-Trp sequence had higher Ki's . Substitution of the phosphinate linkage (PO2-CH2) for the peptide bond also gives potent inhibitors such as napthoyl-GlyP-C-Leu-Trp-NHBzl, the phosphinate analog of naphtholyl-Gly-Leu-Trp-NHBzl, which has a Ki of 10 nM . Some of the phosphonamidates and phosphinates are also excellent inhibitors of the bacterial zinc metalloproteases thermolysin and Pseudomonas aeruginosa elastase.

Matrix Suppl, 1992, 1, 112 - 5
Crystallographic structures of the elastase of Pseudomonas aeruginosa; McKay DB et al.; The elastase protein of Pseudomonas aeruginosa is a zinc metalloprotease which has been shown to be a member of the bacterial neutral protease family . Its overall tertiary structure is similar to that of thermolysin . The x-ray crystallographic structure of the elastase has been solved to high resolution in three different crystal forms . Substantial conformational differences are observed in the protein in different crystal forms . In the absence of ligand, and independently in the presence of a covalent noncompetitive inhibitor, the elastase is observed to have a relatively "open" substrate binding cleft, while in the presence of tight-binding competitive inhibitors, the active site cleft is "closed".

Surg Today, 1992, 22(6), 504 - 7
Bacterial adherence to human gallbladder epithelium; Sakurai S et al.; The adherence of Escherichia coli and Pseudomonas aeruginosa to the epithelium of the gallbladders obtained from 32 patients with negative bile culture was quantified by a scanning electron microscope . Of the gallbladders, 5 were histologically normal (group A), 21 had chronic calculus cholecystitis (group B), and 6 had acute calculus cholecystitis (group C) . The data were expressed as the mean +/- S.D . of the numbers of adherent bacteria to 1,000 microns2 of the gallbladder epithelium . The number of adherent E . coli were 0.1 +/- 0.2 in group A, 4.2 +/- 2.8 in group B, and 9.2 +/- 3.3 in group C . A similar result was also observed with P . aeruginosa . The number of adherent bacteria, both of E . coli and P . aeruginosa were significantly higher in group C than in groups A and B, and were also significantly higher in group B compared to group A . The amount of bacterial adherence paralleled that of the degree of epithelial damage, and the normal epithelium proved to have an inhibiting ability . Thus, a secondary bacterial infection is more likely to happen in patients with contaminated bile, and therefore, the treatment for acute cholecystitis should be based either on the results of a bile culture or according to predictive factors for bactibilia.

Microbios, 1992, 72(290), 7 - 16
Sensitivity of Pseudomonas stutzeri to EDTA: effects of growth parameters and test conditions; Temple GS et al.; EDTA is highly toxic for Pseudomonas stutzeri . The bactericidal effect is not significantly attenuated by treatment of the cells at 0 degrees C rather than 25 degrees C, nor by osmotic stabilisation of the treated cells . The few surviving cells are not genetically resistant, but resistance to EDTA (and to some cationic antibiotics) can be induced by growing organisms in magnesium-limited media . Under these conditions, there is increased production of a protein of molecular mass about 20 kD . Comparable results have been reported for Pseudomonas aeruginosa . The mode of action of EDTA on these pseudomonads is discussed.

Intensive Care Med, 1992, 18(7), 430 - 2
Fulminant primary Pseudomonas aeruginosa pneumonia and septicaemia in previously well adults; Henderson A et al.; We report two cases of primary, community acquired, Pseudomonas aeruginosa pneumonia, occurring in previously well adults without any recognisable environmental risk factors . Both patients died within 36 h of the onset of symptoms, despite broad spectrum antibiotics and aggressive supportive care . In neither case was the diagnosis considered in life and neither patient received adequate anti-pseudomonas therapy . Heightened awareness of this rare, fulminant, variant of primary Pseudomonas pneumonia is required if specific anti-pseudomonas therapy is to have any impact on outcome.

Agents Actions Suppl, 1992, 38 ( Pt 3), 329 - 42
Hageman factor dependent activation and its relationship to lethal Pseudomonas aeruginosa burn wound infections; Holder IA et al.; Trauma causes increases in total protease load in the circulation of the traumatized host animal or patient . This increase is due, in part, to Hageman Factor activation followed by down-line cascade system activation . Concomitant with the activation of these systems is a reduced host capacity to resist infection . Infection superimposed on a traumatized host increases the total host protease load even more by additional activation of Hageman Factor and cascade systems.

Dev Biol Stand, 1992, 77, 121 - 8
Protodyne: an immunostimulatory protein component, prepared from gram-positive Bacillus subtilis; Houba V et al.; A protein component derived from bacterial protoplasm, called Protodyne, increases the non-specific resistance to infections by bacteria and viruses . Here we show that Protodyne can be prepared not only from Gram-negative bacteria, but also from Gram-positive bacilli . Several preparations of Protodyne, prepared from Bacillus subtilis by phenol extraction or by ammonium sulfate precipitation, were evaluated for immunomodulatory activities in a variety of assays . Protodyne had a marked mitogenic activity on mouse spleen cells; it was a potent inducer of tumor necrosis factor (TNF) and stimulated production of interleukin-1 (IL-1) in human peripheral blood mononuclear cells; it increased the capacity of activated macrophages to undergo a respiratory burst, to produce intracellular killing of leishmanial parasite and extracellular lysis of mastocytoma cells; it also stimulated phagocytosis of latex particles, and prolonged survival of immunosuppressed mice infected with Pseudomonas aeruginosa . These activities were not inhibited by polymyxin B, indicating that the activity of Protodyne is not the result of contamination with exogenous lipopolysaccharide . It appears that Protodyne exerts its many immunomodulatory actions by inducing the release of soluble mediators, including TNF and IL-1.

Microbios, 1992, 70(284-285), 215 - 30
Mechanism of action of chlorhexidine diacetate and phenoxyethanol singly and in combination against gram-negative bacteria; Fitzgerald KA et al.; Chlorhexidine diacetate and the aromatic alcohol, phenoxyethanol in combination had an enhanced bacteriostatic action against Escherichia coli and Pseudomonas aeruginosa strains . Investigations of potassium (K+) ion leakage by means of a potassium electrode and a radioactive method, employing 86Rb, indicated that the combination accelerated the rate of leakage from the cell . Leakage of pentose was also found to be enhanced in the presence of the combination compared with either drug alone.

C R Acad Sci III, 1992, 314(13), 587 - 92
{Fragmentation of fibronectin in cystic fibrosis}; Allal M et al.; Fibronectin (FN) plays an important role in mediating cell-matrix interactions and also as an opsonin in the phagocytosis of some microorganisms . Due to its domain structure FN is easily attacked by proteolytic enzymes and especially by elastases . Some of the fragments possess original properties as potentiation of viral transformation or proteolytic activity absent in the intact molecule . Cystic fibrosis is frequently accompanied by infection with protease generating microorganisms, such as Pseudomonas aeruginosa . Polyacrylamide gel electrophoresis and immunoblotting revealed the presence of FN fragments in the plasma of patients with molecular weight between 30 and 100 kD . Purified plasma FN was rapidly hydrolyzed in fragments by the sputum of patients as well as by purified Pseudomonas elastase . The comparison of fragments detected in patients' plasma with those produced by in vitro proteolysis confirms the probability of in vivo fragmentation of FN in cystic fibrosis and suggests that several proteolytic enzymes, endogenous and of bacterial origin, might be involved.

Biomaterials, 1992, 13(7), 417 - 20
Surface-immobilized polyethylene oxide for bacterial repellence; Desai NP et al.; Polyethylene terephthalate films were surface-modified with polyethylene oxide (18,500 g/mol) using a solution technique described previously . These films were investigated for their resistance to bacterial adhesion . Three bacterial strains most commonly associated with implant infections, Staphylococcus epidermidis, Staphylococcus aureus and Pseudomonas aeruginosa, were cultured in tryptic soya broth, human plasma and human serum on the polymeric substrates . Significant reductions (between 70 and 95%) in adherent bacteria were observed on the polyethylene oxide-modified substrates compared to the untreated control polyethylene terephthalate . Surface modification with polyethylene oxide may reduce the risk of implant-associated infections . Plasma fibrinogen was observed to play an important role in the adhesion of all three of these species on both the polyethylene oxide-modified and control polyethylene terephthalate materials.

Kansenshogaku Zasshi, 1992 Jan, 66(1), 76 - 80
Effect of recombinant human granulocyte colony-stimulating factor (G-CSF) in the treatment of Pseudomonas aeruginosa bacteremia complicating hematologic malignancy--a preliminary study; Funada H et al.; The efficacy of recombinant human granulocyte colony-stimulating factor (G-CSF) in the treatment of Pseudomonas aeruginosa bacteremia in cancer patients receiving intensive chemotherapy was studied retrospectively . In 14 of the 24 episodes of P . aeruginosa bacteremia, which occurred in 23 severely neutropenic patients with hematologic malignancies during a three-year period, G-CSF was given subcutaneously or intravenously at daily doses of 75 micrograms/body to 200 micrograms/m2 of body surface . Overall, survival at one week after onset was observed in 13 patients (54%) . Treatment with G-CSF, however, had no statistically significant association with one-week survival, although a favorable outcome was well correlated with an increase in the neutrophil count during therapy . On the other hand, septic shock and appropriate antibiotic therapy were the major prognostic factors . The frequency of shock was reduced by appropriate therapy, but not by G-CSF treatment . These preliminary findings thus suggested that G-CSF should not be effective in the treatment of neutropenic cancer patients with P . aeruginosa bacteremia . No adverse effects of G-CSF were observed.

Jpn J Antibiot, 1992 Jan, 45(1), 98 - 105
{Combination effect of KW-2228 and aminoglycoside antibiotics on systemic infection in cyclophosphamide-treated tumor-bearing mice}; Yoshino T et al.; A modified recombinant human granulocyte colony-stimulating factor (rhG-CSF), KW-2228, has some excellent properties such as high specific activity in stimulating granulocyte colony-formation in vitro, great biological stability in plasma, good pharmacokinetic profile and high potency in granulopoiesis in normal mice in vivo . Recently, the application of G-CSF against infectious diseases has been considered, and some animal experiments have been carried out to support its clinical applications . Patients with underlying diseases such as leukemia and cancer often have recurrent infections because of reduced numbers or functions of neutrophils, which mediate an early stage of host defense . In out present study, we established a new method to evaluate in vivo potency of G-CSF in colon 26 tumor-bearing mice . By using the method, we examined combination effects of KW-2228 with aminoglycoside antibiotics against a systemic infection caused by Pseudomonas aeruginosa . KW-2228 (1 microgram/mouse/day) was administered (s.c.) once a day for 4 days before the bacterial infection was introduced in colon 26 tumor-bearing mice receiving cyclophosphamide 3 days after the transplantation of tumor . Antibiotics were administered (s.c.) 2 hours after the introduction of the bacterial infection . ED50 of gentamicin (GM) alone and that of the combination with KW-2228 were 40.7 mg/kg and 3.6 mg/kg, respectively . ED50 of astromicin (ASTM) alone and that of the combination with KW-2228 were 386 mg/kg and 17.8 mg/kg, respectively . Thus the combination therapy of KW-2228 with GM or ASTM exhibited excellent protective effects in comparison to the treatment with antibiotic alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Jpn J Antibiot, 1992 Jan, 45(1), 87 - 90
{Protective effect of KW-2228 in a systemic infection model of CPA-treated tumor-bearing mice}; Yoshino T et al.; A modified recombinant human granulocyte colony-stimulating factor (rhG-CSF), KW-2228, has some excellent properties such as high specific activity in stimulating granulocyte colony-formation in vitro, great biological stability in plasma, good pharmacokinetic profile and high potency in granulopoiesis in normal mice in vivo . Recently, the application of G-CSF against infectious diseases has been considered, and some animal experiments have been carried out to support its in clinical applications . Patients with underlying diseases such as leukemia or cancer often have recurrent infections because of reduced number and functions of neutrophils, which mediate an early stage of host defense . We investigated the prophylactic effect of KW-2228 against an experimental systemic infection with Pseudomonas aeruginosa in tumor-bearing mice (colon 26: BALB/c) treated with cyclophosphamide . KW-2228 (0.25-2.0 micrograms/mouse) was administered (s.c.) once a day for 4 days before the experimental bacterial infection . As a result of KW-2228 administration, the reduction in peripheral blood neutrophils usually caused by the injection with cyclophosphamide was prevented markedly . KW-2228 displayed excellent protective potency dose-dependently against the infection with P . aeruginosa in tumor-bearing mice . These data show the possibility that prophylactic therapy with KW-2228 may augment the host defense of immunocompromised patients to infections . It present, clinical efficacy studies on KW-2228 are under way.

J Bacteriol, 1992 Jan, 174(2), 471 - 6
Overexpression in Escherichia coli and functional analysis of a novel PPi-selective porin, oprO, from Pseudomonas aeruginosa; Hancock RE et al.; Immediately upstream from and adjacent to the oprP gene, which codes for the phosphate-specific porin OprP of Pseudomonas aeruginosa, lies the PR region (oprO), which cross-hybridizes with oprP DNA . To determine the function of this region, the oprO gene was expressed behind the lactose promoter in Escherichia coli, and the resultant OprO protein was purified and reconstituted into planar lipid bilayers . OprO formed sodium dodecyl sulfate-stable trimers, cross-reacted immunologically with OprP, and, like OprP, formed an anion-specific, phosphate-selective porin . However, it demonstrated lower affinity for and higher maximal conductance of both chloride and phosphate than did the OprP channel . Examination by macroscopic conductance inhibition experiments of the affinity of OprO for phosphates of different lengths revealed a preference for PPi and tripolyphosphate over Pi, suggesting that OprO functioned as a PPi-selective polyphosphate channel, in contrast to OprP, which has a marked preference for Pi.

Adv Perit Dial, 1992, 8, 325 - 7
Exit-site/tunnel infection and catheter outcome in peritoneal dialysis patients; Wadhwa NK et al.; STUDY OBJECTIVE: To study exit-site/tunnel infections and catheter outcomes in peritoneal dialysis patients . DESIGN: The study was designed to investigate exit-site (ESI)/tunnel infections (TI) and catheter losses in all chronic PD catheters inserted in ESRD patients from 9/88 to 9/91 . SETTING: Tertiary-referral university hospital . PATIENTS AND METHODS: Seventy-three patients (40 males, 33 females) underwent 78 double-cuff coiled swan-neck catheter implantations surgically . The curettage of exit site was performed weekly for tunnel infection refractory to medical management . The subcutaneous cuff was excised in persistent ESI/TI . RESULTS: Fifty-nine episodes of ESI/TI in 34 patients were observed over 946 patient-months . Thirty-nine patients experienced no ESI/TI, 27 patients had one and seven had two or more episodes of ESI/TI . Four patients had five episodes of peritonitis associated with ESI/TI . Eight recurrent episodes of ESI/TI with S . aureus in 8 patients were treated successfully with Rifampin . Seven subcutaneous cuffs were excised successfully in 7 patients with tunnel infection, five with S . aureus and two with Pseudomonas aeruginosa . No catheter was removed due to ESI/TI or ESI/TI associated peritonitis . CONCLUSIONS: Aggressive exit site care including repeated curettage, excision of the subcutaneous cuff and appropriate antibiotics reduced significantly catheter losses related to ESI/TI.

Zh Mikrobiol Epidemiol Immunobiol, 1992 Jan, (1), 16 - 8
{The hemagglutinating properties of Pseudomonas aeruginosa strains isolated from patients with nonspecific lung diseases}; Dalina AM et al.; To detect d-mannose-sensitive (MS) pili in 31 P . aeruginosa strains isolated from the respiratory tract of patients with inflammatory and purulent destructive pulmonary diseases, the hemagglutination (HA) test was used . The isolated Pseudomonas under study differed in the degree of manifestation of their MS adhesins . Among them microorganisms with pronounced HA activity (high HA titer) occurred, as well as those whose HA activity was less pronounced (low HA titer) . P . aeruginosa strains with pronounced HA activity were more frequently isolated from patients with purulent destructive processes in the lungs . A correlation between the state of the patient at the moment of bacteriological examination and the degree of manifestation of MS pili in the P . aeruginosa strain isolated from this patients was established . The value of HA titer in the presence of d-mannose is indicative of the presence of MS adhesins in a P . aeruginosa strain.

Mem Inst Oswaldo Cruz, 1992, 87 Suppl 5, 61 - 8
Pseudomonas aeruginosa adhesion to normal and injured respiratory mucosa; Plotkowski MC et al.; Human nasal polyps in outgrowth culture were used to study the adhesion of Pseudomonas aeruginosa to respiratory cells . By transmission electron microscopy, bacteria associated with ciliated cells were identified trapped at the extremities of cilia, usually as aggregates of several bacterial cells . They were never seen at the interciliary spaces or attached along cilia . Bacteria were also seen to adhere avidly to migrating cells of the periphery of the outgrowth culture . Using a model of repair of wounded respiratory epithelial cells in culture, we observed that the adhesion of P . aeruginosa to migrating cells of the edges of the repairing wounds was significantly higher than the adhesion to non-migrating cells and that adherent bacteria were surrounded by a fibronectin-containing fibrillar material . The secretion of extracellular matrix components is involved in the process of epithelium repair following injury . To investigate the molecular basis of P . aeruginosa adhesion to migrating cells, bacteria were treated with a fibronectin solution before their incubation with the respiratory cells . P . aeruginosa treatment by fibronectin significantly increased their adhesion to migrating cells . Accordingly, we hypothesize that during cell migration, fibronectin secreted by epithelial cells may favour P . aeruginosa adhesion by establishing a bridge between the bacteria and the epithelial cell receptors . Such a mechanism may represent a critical step for P . aeruginosa infection of healing injured epithelium.

Drugs Exp Clin Res, 1992, 18(7), 291 - 4
In vitro and in vivo evaluation of BMY 45243, a new 5-amino-naphthyridone derivative; Bouzard D et al.; BMY 45243 is the first representative of 5-amino naphthyridone derivatives prepared following a new methodology developed by the authors . BMY 45243 is a highly lipophilic compound, very active in vitro and in vivo on S . aureus and was found to be as potent as ciprofloxacin on Gram-negative organisms with identical in vivo activity against Pseudomonas aeruginosa . Pharmacokinetics in mice showed better AUC and Cmax and longer t1/2 for BMY 45243 than for sparfloxacin and ciprofloxacin.

Int Arch Allergy Immunol, 1992, 99(1), 98 - 106
Alginate--its role in neutrophil responses and signal transduction towards mucoid Pseudomonas aeruginosa bacteria; Konig B et al.; Mucoid Pseudomonas aeruginosa bacteria impaired neutrophil functions, e.g . chemiluminescence response, and leukotriene formation to a significantly higher degree as compared to nonmucoid P . aeruginosa bacteria . To study the cell biological requirements for the different cellular response pattern by mucoid and nonmucoid (NM) P . aeruginosa bacteria, further experiments were performed with purified alginate, the mucoid exopolysaccharide of P . aeruginosa (MEP) . In this regard the MEP (alginate) significantly reduced the zymosan-induced leukotriene B4 (LTB4) formation (from 40 +/- 7 to 2 +/- 4 ng) . The chemiluminescence response induced by NM bacteria was abolished when the bacteria were precoated with the MEP . Mucoid and NM P . aeruginosa bacteria interacted with components of the cellular signal transduction pathway to a different degree . Mucoid bacteria induced a 2-fold enhanced GTPase activity but activated the protein kinase C (PKC) to a lesser degree than NM P . aeruginosa bacteria . Prior exposure of neutrophils to the MEP increased the sodium fluoride (NaF)-induced GTPase activity and guanylylimidodiphosphate binding {Gpp(NH)p} by approximately 60 and 30%, respectively . The phorbol myristic acid-induced PKC activation was inhibited by 30-40% in the presence of the MEP . However, the MEP by itself was inactive in all assay systems . Our results indicate that the MEP represents an important component which modulates neutrophil responses of mucoid as compared to NM P . aeruginosa bacteria, e.g . the chemiluminescence response, LTB4 generation, and the interaction with components (G proteins, PKC) of the signal transduction pathway.

FEMS Microbiol Lett, 1992 Jan 1, 69(2), 205 - 9
NAD-dependent glutamate dehydrogenase from Pseudomonas aeruginosa is a membrane-bound enzyme; Joannou CL et al.; Measurements of the deaminating activity of NAD-dependent glutamate dehydrogenase (NAD-GDH) in Pseudomonas aeruginosa strain 8602 (PAC 1) showed an initially constant rate that gave way to a 3.5-fold increased rate on prolonged incubation . Only the faster rate was observed when assay mixtures were preflushed with nitrogen or were treated with the detergent Triton X-100 . Comparison of the intracellular distribution of NAD-GDH with marker enzymes showed it to be associated with the cytoplasmic membrane . The results suggest that NAD-GDH may be linked to oxygen through an electron-transport system.

Proc Natl Acad Sci U S A, 1992 Jan 1, 89(1), 47 - 51
Components of the protein-excretion apparatus of Pseudomonas aeruginosa are processed by the type IV prepilin peptidase; Nunn DN et al.; In the Gram-negative pathogen Pseudomonas aeruginosa, mutants in the gene for the prepilin peptidase (pilD) are pleiotropic, as they not only fail to process pilin but also accumulate in the periplasm, in their mature form, several toxins and hydrolytic enzymes that are normally exported to the external medium (excreted) . We have suggested that this excretion defect is due to the lack of PilD-dependent processing of proteins that share sequences in common with the prepilin subunit and that are components of a protein-excretion machinery . In this paper we report the isolation and characterization of transposon-induced excretion mutants with phenotypes similar to that of a pilD gene mutant . Using oligonucleotide probes designed to recognize sequences encoding the cleavage site of the type IV prepilins, we have isolated four linked genes with the predicted putative PilD-dependent cleavage site . Site-specific mutations within these genes have shown that they are required for protein excretion, and PilD-dependent processing of at least one of the four encoded proteins was demonstrated . Evidence suggests that similar components play a role in protein excretion in a wide variety of Gram-negative bacteria.

Plant J, 1992 Jan, 2(1), 129 - 31
Molecular characterization of glutathione reductase cDNAs from pea (Pisum sativum L.); Creissen G et al.; A cDNA for pea glutathione reductase has been cloned and sequenced . The derived amino acid sequence of 562 residues shows a high degree of homology to the previously published GR sequences from human erythrocytes and from two prokaryotes: Escherichia coli and Pseudomonas aeruginosa . The pea enzyme differs from other GRs in having an N-terminal leader sequence of about 60-70 residues which may be a chloroplast transit peptide and a 20 amino acid C-terminal extension of unknown function.

Ann Radiol (Paris), 1992, 35(6), 494 - 9
{Atypical osteomyelitis of the base of the skull and malignant otitis externa}; Sanhaji L et al.; Osteomyelitis of the skull base is a rare, but serious disease whose incidence is tending to increase . It affects the marrow of the temporal, occipital and sphenoid bones and is generally secondary to Pseudomonas aeruginosa infection of the external auditory meatus . Based on a clinical case, the authors recall the difficulty of establishing the positive diagnosis and the possible confusion with neoplastic disease, hence the fundamental role of biopsies . They also review the literature on this subject.

Scand J Infect Dis, 1992, 24(6), 815 - 7
Isolated severe thrombocytopenia and bleeding caused by piperacillin; Olivera E et al.; Bleeding and severe thrombocytopenia developed in a 71-year-old man who had been receiving piperacillin 5 g intravenously every 8 h for 9 days for the treatment of Pseudomonas aeruginosa septicemia . After piperacillin was discontinued, the platelet counts became normal . Rechallenge was made with 2 g of piperacillin intravenously resulting in thrombocytopenia within 6 h of piperacillin administration . The platelet count normalized after 3 days when no further piperacillin was given.

Scand J Infect Dis, 1992, 24(6), 797 - 800
Long-term oral ciprofloxacin in the treatment of prosthetic valve endocarditis due to Pseudomonas aeruginosa; Uzun O et al.; Prosthetic valve endocarditis caused by Pseudomonas aeruginosa is refractory to medical treatment alone and early valve replacement is necessary . We describe a 40-year-old patient in whom endocarditis developed in the early postoperative period, and reoperation was not considered feasible . Ciprofloxacin was administered orally in order to suppress bacteremia for 36 months . Long-term oral ciprofloxacin may provide an opportunity in the treatment of prosthetic valve endocarditis caused by Ps . aeruginosa in patients who are unfavorable candidates for reoperation.

Med Microbiol Immunol (Berl), 1992, 181(6), 339 - 49
Determination of IgG subclass antibodies to Pseudomonas aeruginosa outer membrane proteins in cystic fibrosis lung infection using immunoblotting and enzyme-linked immunosorbent assay; Pressler T et al.; IgG subclass antibodies to Pseudomonas aeruginosa outer membrane proteins (OMP) were investigated in serum from cystic fibrosis (CF) patients by immunoblotting and enzyme-linked immunosorbent assay (ELISA) . Fifteen patients (eight in good and seven in poor clinical condition) have been followed for an average of 13 years with multiple serum samples covering the preinfection, and early and late stages of chronic infection . Laser-scanning densitometry of photographs taken from immunoblots was used to quantify antibody level and compare with ELISA titres . The earliest anti-OMP antibodies to appear were of the IgG1 subclass . There was no significant difference in IgG subclass antibody levels to OMPs between patients in relatively good and poor clinical condition . Data presented indicate a high positive correlation among measurements of IgG subclass antibodies to P . aeruginosa OMPs using ELISA and immunoblotting.

Microbiol Immunol, 1992, 36(12), 1305 - 16
Establishment of stable cell lines producing anti-Pseudomonas aeruginosa monoclonal antibodies and their protective effects for the infection in mice; O'Oka H et al.; Human-human hybridomas producing monoclonal antibodies (MoAbs) specific for five major serotypes of Pseudomonas aeruginosa were developed by fusing P . aeruginosa primed and Epstein-Barr virus-transformed cells with human myeloma P109 cells using polyethyleneglycol . The MoAbs which were produced by the hybridomas were protective against lethal intraperitoneal (i.p.) challenge of P . aeruginosa (10 LD50) in mice . The 50% effective dose (ED50) values of MoAbs ranged from 0.5 to 10.2 micrograms/mouse and were 26 to 240 times more protective than a commercial human IgG preparation . MoAb administration to mice promoted bacterial clearance in peritoneal cavity, and prevented bacterial invasion into blood in the way of increasing both the number of bacteria trapped by a macrophage and the ratio of macrophages that trapped bacteria . MoAbs also showed protective effects against lethal infection of P . aeruginosa in the mice which were decreased in polymorphonuclear cells (PMN) by cyclophosphamide (CY) . All MoAbs showed serotype-specific binding to the clinical isolates of P . aeruginosa as well as to the immunized strains . The hybridoma cell lines maintained their capacity to produce MoAb continuously for more than 12 months and produced 10 to 60 micrograms MoAbs per 10(6) cells in 24 hr . It is practicable to use these cell lines for large-scale production of anti-P . aeruginosa MoAbs and such MoAbs must be useful for the therapeutics of patients with P . aeruginosa infection.

Eur J Biochem, 1991 Dec 18, 202(3), 1275 - 82
Hypochlorous acid and myeloperoxidase-catalyzed oxidation of iron-sulfur clusters in bacterial respiratory dehydrogenases; Hurst JK et al.; Hypochlorous acid and related oxidants derived from myeloperoxidase-catalyzed reactions contribute to the microbicidal activities of phagocytosing neutrophils and monocytes . Microbial iron-sulfur (Fe/S) clusters have been suggested as general targets of myeloperoxidase-derived oxidations, but no susceptible Fe/S site has yet been identified . In this study, the effects of HOCl and myeloperoxidase-catalyzed peroxidation of chloride ion upon EPR-detectable Fe/S clusters in Escherichia coli and Pseudomonas aeruginosa were examined . Increasing amounts of oxidant produced progressive loss of signal amplitudes from the S-1 and S-3 Fe/S clusters of succinate:ubiquinone oxidoreductase in respiring membrane fragments . These changes were compared to loss of microbial viability, succinate uptake rates, succinate dehydrogenase activity and succinate-dependent respiration . The amounts of oxidant required to destroy Fe/S clusters exceeded the amounts required to kill organisms or inhibit respiratory function by factors of four or five . Power saturation characteristics of the S-1 signal indicated that the S-2 signal was also resistant to modification, even in highly oxidized membranes . Loss of succinate-dependent respiration was closely associated with HOCl and myeloperoxidase-mediated microbicidal activity against P . aeruginosa and was also an early event in the oxidant-mediated metabolic dysfunctions of E . coli . However, these effects were not caused by the destruction of the Fe/S clusters within the succinate:ubiquinone oxidoreductase . Rather, the major respiration-inhibiting lesion(s) appeared to reside at points in the respiratory chain between the Fe/S clusters and the ubiquinone reductase site.

J Mol Biol, 1991 Dec 20, 222(4), 869 - 71
Crystallization of and preliminary X-ray data for the negative regulator (AmiC) of the amidase operon of Pseudomonas aeruginosa; Wilson SA et al.; The negative regulator (AmiC) of the amidase operon of Pseudomonas aeruginosa has been purified from an over-expressing clone and crystalized . Crystals of diffraction quality were obtained from polyethylene glycol 4000 and ammonium sulphate . AmiC crystallizes in P4(2)2(1)2 (a = 104.4 A, c = 66.6 A) with one subunit in the asymmetric unit . Crystals diffract beyond 2.8 A.

FEMS Microbiol Lett, 1991 Dec 15, 69(1), 43 - 8
A plasmid from a virulent strain of Legionella pneumophila is conjugative and confers resistance to ultraviolet light; Tully M; The presence of a single apparently cryptic plasmid of approximately 36 MDa was demonstrated in the virulent Dodge strain of Legionella pneumophila . 'Tagging' of the plasmid with Tn5 enabled transfer to be demonstrated to other strains of Legionella (though not to Escherichia coli or Pseudomonas aeruginosa) as well as a definitive assessment to be made of its stability . Plasmid carriage confers resistance to UV light probably by means of an error-prone UV repair system . The plasmid is compatible with plasmids of the IncP and IncW incompatibility groups.

Am J Kidney Dis, 1991 Dec, 18(6), 674 - 7
Exit-site and tunnel infections in continuous ambulatory peritoneal dialysis patients; Scalamogna A et al.; One hundred two exit-site infections (ESI) were diagnosed in 63 of 163 (38.6%) patients, with an incidence of one episode every 23.7 patient-months in patients with a history of ESI, whereas in the overall continuous ambulatory peritoneal dialysis (CAPD) population the incidence was one episode every 48.7 patient-months . In diminishing order of frequency, the bacteria isolated were Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Escherichia coli . The probability of remaining free of ESI was 72% at 1 year and 45% at 5 years . The ESI that led to catheter removal were due to S aureus and gram-negative rods . In 13 (48%) of 27 S aureus ESI unresponsive to antibiotics and local care, deroofing and outer cuff shaving completely resolved the ESI . Despite this treatment, the catheters of the remaining 14 patients had to be removed because of peritonitis associated with the tunnel infection . In conclusion, ESI is a major cause of CAPD failure . In our series, shaving the cuff as a rescue treatment was effective for almost 50% of the patients with antibiotic-resistant S aureus ESI.

Chest, 1991 Dec, 100(6), 1607 - 13
Role of chronic Pseudomonas aeruginosa infection in airway mucosal permeability; Ishihara H et al.; The role of Pseudomonas aeruginosa infection in airway mucosal permeability was studied in 16 patients with chronic bronchitis by measuring the amounts of radiolabeled albumin in sputum . One group (A) consisted of six patients (two female, four male, 53 +/- 6 years, SEM) with chronic P aeruginosa infection for 5 +/- 0.9 years . Another group (B) consisted of ten patients (five female, five male, 67 +/- 4 years) without P aeruginosa infection for at least two years . No significant differences between groups A and B were found in the volume of sputum (63 +/- 21 ml/day in group A and 45 +/- 8 ml/day in group B, p = 0.44), the obstructive changes (FEV1 of 57 +/- 6 percent in group A and 51 +/- 4 percent in group B), or the duration of disease (19 +/- 4 years in group A and 14 +/- 4 years in group B) . Saliva, sputum, and serum samples were collected at intervals of 2 h over an 8-h period, and at 24 h after intravenous administration of 131I-labeled human albumin . For counting, free 131I was removed by dialysis . Radiocounts (cpm) of saliva were significantly smaller than those of sputum or serum . The cpm from each sputum sample was divided by serum cpm at the time of each sampling . Group A showed significantly higher values in the ratio of sputum- to serum-cpm than did group B at all sampling times . Furthermore, the ratios at 2 and 4 h after 131I-albumin injection significantly correlated with sputum volume per day, whereas they did not correlate with any other factors (age, obstructive impairment, and duration of disease) . These findings suggest that chronic P aeruginosa infection produces an increase in airway mucosal permeability to albumin.

Am J Respir Cell Mol Biol, 1991 Dec, 5(6), 563 - 70
Characterization of Pseudomonas aeruginosa adherence to cultured hamster tracheal epithelial cells; Grant MM et al.; This study reports an in vitro system that allows the convenient study of both microenvironmental and bacterial factors affecting adherence of Pseudomonas aeruginosa to tracheal epithelium . Primary cultures of mixed ciliated and nonciliated epithelial cells isolated from hamster tracheas were grown on collagen-coated multiwell plates containing 10(5) epithelial cells/well at confluence . When 10(7) 14C-labeled P . aeruginosa (nonmucoid, strain Y-4) suspensions were added to each well, 8.13 +/- 2.6% (mean +/- SD) of the initial inoculum bound to the cultured cells, an amount comparable to that measured using suspensions of human tracheal epithelial cells and the same bacteria . The bacteria adhered preferentially to the cultured cells rather than to an acellular collagen matrix . Five additional nonmucoid strains of P . aeruginosa also bound well to the cultured cells, while two mucoid strains were less adherent . Strains of two other gram-negative bacteria, Pseudomonas maltophilia and Klebsiella pneumoniae, did not bind significantly, emphasizing the bacterial species specificity of the adherence interaction being measured . The binding interaction with P . aeruginosa was both pH-sensitive and altered by the presence of the divalent cation calcium . Thus, the in vitro assay system described provides a consistent surface of tracheal epithelial cells that binds P . aeruginosa in a specific manner and can be used to examine the effects of bacterial variables and microenvironmental conditions that may be present in the human airway.

J Chemother, 1991 Dec, 3(6), 363 - 6
Indirect transfer of resistance to imipenem in a strain of Pseudomonas aeruginosa; Krcmery V et al.; Determinants of resistance of imipenem can be, in Pseudomonas aeruginosa strains resistant to this drug, transferred by transduction with wild-type phages as well as mobilized for conjugal transfer, as demonstrated by the indirect selection procedure . Exconjugants obtained in the latter type of experiments do not transfer imipenem resistance determinant to further recipient strains(s) by conjugation . Mobilized imipenem resistance is of non-hydrolytic character and its biochemical mechanism is unknown at present.

J Antimicrob Chemother, 1991 Dec, 28(6), 869 - 75
The resistance patterns and serotypes of Pseudomonas aeruginosa strains isolated from children; Patzer J et al.; Among 916 Pseudomonas aeruginosa strains isolated from children in a Warsaw hospital during the period 1985-1988 the most frequently encountered serotypes were O6, O11, O12, and O16 . The majority of isolates resistant to aminoglycosides were characterized by simultaneous resistance to gentamicin and tobramycin and belonged to serotype O11 . Among isolates resistant to beta-lactam antibiotics the most frequently encountered serotype was O6, followed by serotype O3 and O11 . Most strains of serotype O12 were resistant to aminoglycosides and beta-lactam antibiotics as has been reported from other countries.

Antimicrob Agents Chemother, 1991 Dec, 35(12), 2649 - 51
Development of resistance to ciprofloxacin in nutrient-rich and nutrient-limited growth conditions in vitro by Pseudomonas aeruginosa isolates from patients with cystic fibrosis; Ferguson MI et al.; Five serial exposures of mucoid Pseudomonas aeruginosa from patients with cystic fibrosis to subinhibitory concentrations of ciprofloxacin resulted in stepwise increases in the MIC, with a mean proportional increase of 10 . MICs were significantly lower in an iron-limited chemically defined medium than in Iso-Sensitest broth . The mucoid phenotype was maintained in chemically defined medium . Acquired resistance was retained either partially or completely in 85% of the isolates following 10 transfers in drug-free media . In cases in which susceptibility was regained, an increase in the MIC was observed on one further exposure to ciprofloxacin.

Antimicrob Agents Chemother, 1991 Dec, 35(12), 2617 - 24
Impact of pH and cationic supplementation on in vitro postantibiotic effect; Gudmundsson A et al.; Most studies on pharmacodynamic variables in vitro, including the postantibiotic effect (PAE), are performed at pH 7.4 in noncationic-supplemented media, a situation which may differ significantly from the true microenvironment in most infected foci . We studied the impact of five different pH levels (pH 5, 6, 7, 7.4, and 8) on the duration of the PAE, the MIC, and bactericidal activity . Acid pH was found to have in general a deleterious effect on the activity of aminoglycosides and ciprofloxacin against Escherichia coli and Pseudomonas aeruginosa, with the MIC being higher, the bactericidal rate being lower, and the PAE being shorter at pH 5 (and to a lesser extent at pH 6) than at more alkaline pH levels . Similar results were observed for imipenem against P . aeruginosa . The PAEs induced by ampicillin against E . coli and dicloxacillin against Staphylococcus aureus were not predictably dependent on the pH, whereas the PAEs induced by ciprofloxacin against S . aureus were longest at either end of the pH spectrum . The bactericidal activity of these agents was, however, pH dependent, being slower at acid pHs . The addition of 50 mg of Ca2+ and 20 mg of Mg2+ per liter of liquid medium at pH 7.4 did not affect the duration of the PAE . Since the pH in abscess cavities may be close to 5, these observations may be of importance for employment of the agents studied in closed or poorly drained infections.

Berl Munch Tierarztl Wochenschr, 1991 Dec 1, 104(12), 414 - 9
{Activation of the resident microbial flora as a possibility for the improvement of humoral antibody potentials}; Lubke A et al.; The effect of a parenteral application of an adjuvant (Propionibacterium acnes) and an adjuvant/antigen combination (Staphylococcus aureus Cowan I/Al(OH)3, Pseudomonas aeruginosa/Al(OH)3 respectively, was tested with regard to the improvement of antibacterial resistance . Parameter was the humoral antibody production (IgG) of rabbits against six facultative pathogen bacterial species (St . aureus, Sc . faecium, Bac . cereus, P . multocida, E . coli, Ps . aeruginosa) and against sheep rod blood cell membranes . The three methods of treatment led to a significant enhancement of IgG-antibodies against the particular homologous antigen . In addition to this specific reaction the application of adjuvant/antigen combinations provoked a significant enhancement of antibodies also against heterologous antigens (P . multocida, Bac . cereus, sheep red blood cell membranes) . The application of P . acnes had no distinct effect on the antibody titer against the different antigen preparations . In order to analyse the immune response qualitatively, a greater part of serum samples was examined by immuno blot technique . The number of partial antigens recognized by the sera increased during the experiments but the rise did generally not relate to developments of antibody titers . Nevertheless, the Ps . aeruginosa/Al(OH)3-treatment seemed to improve the ability of sera to detect antigenic determinants of heterologous bacterial species.

J Antibiot (Tokyo), 1991 Dec, 44(12), 1371 - 93
Studies on condensed-heterocyclic azolium cephalosporins . I . Synthesis and antibacterial activity of 7 beta-{2-(2-aminothiazol-4-yl)-2(Z)- alkoxyiminoacetamido}-3-(imidazo{1,2-a}pyridinium-1-yl)methyl-3- cephem-4-carboxylates; Nishimura T et al.; In our study of the structure-activity relationships of cephalosporins bearing quaternary ammonium groups at the 3 position, we postulated that delocalization of the azolium positive charge would lead to an expanded antibacterial spectrum and increased activity . Since quaternization of condensed-heterocyclic compounds such as imidazo{1,2-a}pyridine gives positive charge delocalization, 7 beta-{2-(2-aminothiazol-4-yl)-2(Z)-alkoxyiminoacetamido} cephalosporin derivatives (1-53) bearing various (imidazo{1,2-a}pyridinium-1-yl)methyl moieties at the 3 position were prepared and their antibacterial activity was determined . As expected, these cephalosporins exhibited potent activity against both Gram-positive and Gram-negative bacteria including Pseudomonas aeruginosa . These results imply that imidazo{1,2-a}pyridine is a quite useful substituent for improving antibacterial activity and spectrum . The structure-activity studies revealed that a favorable substituent on the imidazo{1,2-a}pyridine is the cyano radical at the 6 position of the ring, and ethoxyimino or 1-carboxy-1-methylethoxyimino groups are suitable for the alkoxyimino substituent . Among the cephalosporins tested, 7 beta-{2-(2-aminothiazol-4-yl)-2(Z)- ethoxyiminoacetamido}-3-(6-cyanoimidazo{1,2-a}pyridinium -1-yl)methyl-3-cephem-4-carboxylate (45) and 7 beta-{2-(2-aminothiazol-4-yl)-2(Z)-(1- carboxy-1-methylethoxyiminoacetamido}-3-(6-cyanoimidazo{1,2- a} pyridinium-1-yl)methyl-3-cephem-4-carboxylate (49) showed good antibacterial activity.

APMIS, 1991 Dec, 99(12), 1061 - 8
Experimental immunization with Pseudomonas aeruginosa alginate induces IgA and IgG antibody responses; Johansen HK et al.; We tried experimentally to induce a specific antibody response against Pseudomonas aeruginosa locally in the airways and systemically in rats by three different routes of immunization; intragastric feeding, intratracheal inoculation or subcutaneous vaccination . Three groups of rats were immunized with live mucoid P . aeruginosa PAO 579 by intragastric feeding or with killed PAO 579 intratracheally or subcutaneously . Three other groups were immunized with purified P . aeruginosa alginate either by intragastric feeding, intratracheally or subcutaneously . At weekly intervals for four weeks animals were sacrificed and serum and bronchial fluid were obtained . The specific IgA and IgG antibody response in lavage fluid and serum was measured . Only traces of antibodies could be detected in the bronchial lavage fluids . Anti-alginate IgA and IgG antibodies developed in all rats immunized with alginate but no antibodies against other P . aeruginosa antigens were detected . The highest IgA and IgG titer against alginate was induced by the subcutaneous immunization . IgA and IgG antibodies against other P . aeruginosa antigens developed in rats immunized with liver and sonicated bacteria . The highest IgA and IgG titers were obtained after intratracheal and subcutaneous immunization with sonicated bacteria . The present work has shown that IgA and IgG antibodies develop with high specificity after immunization . The different titers obtained do not necessarily reflect different degrees of protection.

Gene, 1991 Dec 1, 108(1), 7 - 14
The broad-host-range plasmid pTF-FC2 requires a primase-like protein for autonomous replication in Escherichia coli; Dorrington RA et al.; A 3202-bp fragment of plasmid pTF-FC2, cloned into PUC19, had previously been identified as the minimum region required for replication in either Pseudomonas aeruginosa or Escherichia coli polA- mutants . During the course of experiments to construct broad-host-range cloning vectors based on the pTF-FC2 replicon, it was found that the 3202-bp fragment had an absolute requirement for some function of the pUC19 vector . This requirement was eliminated in the presence of co-resident pTF-FC2 derivatives . An additional 1239-bp fragment from pTF-FC2, immediately adjacent to the 3202-bp fragment, was identified which restored the ability of the pTF-FC2 replicon to replicate autonomously . Sequence analysis of the region revealed a single open reading frame encoding a 40-kDa polypeptide, which was synthesised in an in vitro transcription/translation system . A comparison of the amino acid sequence of this protein with sequence data banks revealed limited homology with the RepB' primase of the IncQ plasmid, RSF1010 . An M13 delta lac 110 replication-deficient phage system was used to demonstrate that the 40-kDa protein did function as a primase with respect to replication at the origin of replication (vegetative) of pTF-FC2.

Gene, 1991 Dec 1, 108(1), 109 - 14
Pseudomonas aeruginosa plasmids as suicide vectors in Escherichia coli: resolution of genomic cointegrates through short regions of homology; Dunn IS; Pseudomonas aeruginosa plasmids which cannot replicate in Escherichia coli have been used to introduce specific modifications into the E . coli chromosome by homologous recombination ('gene targeting') . The E . coli gene (gpt) encoding guanine-xanthine phosphoribosyltransferase (Gpt) was used for initial targeting studies owing to the availability of a powerful positive selection for loss of the Gpt+ phenotype (6-thioguanine resistance or 6TGR or Gpt-) . P . aeruginosa plasmids containing selectable markers flanked by gpt sequences were introduced as supercoiled DNA into an E . coli strain which contained a normal gpt locus . Primary cointegration of such plasmids into the E . coli genome results in a gene duplication event which maintains Gpt function; a secondary recombinational event which resolves the cointegrate either reverses the primary event or results in replacement of the original gpt copy with the modified version . A 316-bp region of homology was sufficient for cointegrate formation, and resolution of the cointegrates through a shorter (92 bp) homologous flank was selectable through loss of Gpt function . The frequency of cointegrate resolution under these conditions was significantly above the spontaneous gpt mutational loss rate.

J Clin Microbiol, 1991 Dec, 29(12), 2758 - 62
Ability of National Committee for Clinical Laboratory Standards-recommended quality control strains from the American Type Culture Collection to detect errors in disk diffusion susceptibility tests; Yechouron A et al.; The National Committee for Clinical Laboratory Standards (NCCLS) recommends, as a quality control for the disk diffusion susceptibility test, the use of three strains from the American Type Culture Collection: Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, and Escherichia coli ATCC 25922 . This study assesses the capacity of these strains to detect errors in the overall method . ATCC strains were tested by comparing testing by the standard NCCLS-recommended procedure (ST) with testing under the following conditions: incubation at 25 degrees C, Mueller-Hinton agar depths of 2 mm (AD2) and 8 mm (AD8), agar pHs of 6.5 and 8, inocula with McFarland standards of 0.25 (0.25M) and 4.0 McFarland (4.0M), direct inoculation without preincubation of inoculum (DI), and a 2-h delay between inoculation and disk application (2HR) . The frequency of zone measurements outside the NCCLS-recommended control zone limits were as follows: ST, 0%; AD2, 18%; AD8, 9.6%; pH 6.5, 7.9%; pH 8, 5.3%; 0.25M, 3.5%; 4.0M, 24%; DI, 3.4%; 2HR, 1.8%; 25 degrees C (only E . coli and P . aeruginosa were evaluable), 28% . These results suggest that the quality control strains are only partially effective in detecting single extreme laboratory errors and that careful laboratory supervision is necessary even in the setting of properly monitored quality control strains.

EMBO J, 1991 Dec, 10(13), 4137 - 44
Mutations in TrpI binding site II that differentially affect activation of the trpBA promoter of Pseudomonas aeruginosa; Gao J et al.; In vitro, Pseudomonas aeruginosa TrpI protein activates transcription initiation at the trpBA promoter (trpPB) and represses initiation at its own promoter (trpPI), which diverges from, and overlaps, trpPB . Indoleglycerol phosphate (InGP) reduces the TrpI concentration required for binding to its strong binding site (site I), as measured by repression of trpPI; it also facilitates activation of trpPB, presumably because it enables TrpI to bind to a weaker binding site (site II) and thereby interact with RNA polymerase . The role of site II and InGP in regulation of the two promoters was investigated by constructing site II mutants . A 2 bp substitution affected the ability of TrpI to activate trpPB, but did not significantly affect TrpI binding to site II . A more extensive (8 bp) substitution inhibited TrpI-mediated activation of trpPB and TrpI-mediated protection of site II in a DNase I footprinting assay . However, the mutation did not alter the pattern of TrpI binding observed in gel retardation experiments . In particular, a more slowly-migrating complex (Complex 2) whose appearance was correlated with TrpI binding to site II was formed equally well on a wild-type or substituted DNA fragment . Based on the mutant phenotypes, we propose that a particular sequence of protein--protein and protein--DNA interactions is required for activation of trpPB by TrpI and InGP.

Mayo Clin Proc, 1991 Dec, 66(12), 1249 - 59
The fluoroquinolones; Walker RC et al.; The fluoroquinolone class of antibiotics promises to become as diverse and as important as beta-lactam agents . The fluoroquinolones inhibit bacterial DNA gyrase and are bactericidal . All fluoroquinolones have potent activity against most gram-negative bacteria; ciprofloxacin is the most active against Pseudomonas aeruginosa . Activity against gram-positive organisms is variable; methicillin-resistant Staphylococcus aureus has acquired resistance to the fluoroquinolones at an alarming rate . Currently available quinolones do not have, but new quinolone agents likely will have, substantial activity against anaerobic bacteria . Some quinolones are also active against Mycobacterium, Chlamydia, and Mycoplasma organisms . All fluoroquinolones have excellent absorption after oral administration; however, this process can be impaired by the presence of aluminum- or magnesium-containing antacids and by zinc, iron, or calcium supplements . Ciprofloxacin is also available for intravenous use . Although most fluoroquinolones do not achieve adequate cerebrospinal fluid levels, penetration into other tissues is excellent . Dosage adjustments for renal and hepatic dysfunction vary among the quinolones . Although side effects are rare, concomitant use of caffeine or theophylline with some quinolones may cause toxicity to the central nervous system . Because they may affect the development of cartilage, all fluoroquinolones are contraindicated in children, adolescents, and pregnant or breast-feeding women.

Invest Ophthalmol Vis Sci, 1991 Dec, 32(13), 3216 - 20
Tobramycin liposomes . Single subconjunctival therapy of pseudomonal keratitis; Assil KK et al.; The authors compared 24 doses of hourly topical fortified tobramycin (Group A) therapy with a single subconjunctival administration of multivesicular megaliposome-encapsulated tobramycin (Group B) and free subconjunctival tobramycin (Group C) in treating a rabbit model of keratitis caused by Pseudomonas aeruginosa . One cornea each of 50 rabbits was infected with P . aeruginosa for 24 hr . The animals then were divided randomly into five groups of ten each . Groups A, B, and C were treated as described . Group D received liposomes without tobramycin and Group E, hourly balanced salt solution . Significantly fewer Pseudomonas colonies were present in the corneas of all three drug-treated groups (A, B, and C) compared with the two control groups (D and E) at 24 hr (P less than 0.005) . Significantly fewer Pseudomonas colonies were present in Groups A and B compared with Group C (P less than 0.02) . No significant difference was noted between Groups A and B (P = 0.30) . Tobramycin encapsulated in megaliposomes may be useful in treatment of pseudomonal keratitis.

Biochem J, 1991 Dec 1, 280 ( Pt 2), 557 - 9
Allosteric regulation of phosphonoacetaldehyde hydrolase by n-butylphosphonic acid; Dumora C et al.; The effect of n-butylphosphonic acid on the activity of phosphonoacetaldehyde hydrolase from Pseudomonas aeruginosa was investigated: at low concentrations this compound appeared as an activator of the enzyme activity, whereas at higher concentrations it exhibited inhibitory properties . The experimental results were modelled according to an allosteric model involving two different classes of sites for n-butylphosphonic acid.

Am Fam Physician, 1991 Dec, 44(6), 2055 - 62
Acute sinusitis: diagnosis and treatment update; Herr RD; Acute sinusitis in adults is manifested by fever, facial pain and purulent rhinorrhea, but children--who rarely have headache or facial tenderness--have persistent cough in addition to fever and purulent rhinorrhea . Sinus transillumination is diagnostically useful only in adults . In children, maxillary sinus radiographs are indicated . New studies show ultrasound examination to be less sensitive than plain radiographs . Cultures obtained by aspiration of the maxillary sinuses are useful in complicated cases . Amoxicillin is still effective as first-line treatment, but treatment failure requires a prompt change to trimethoprim-sulfamethoxazole or ciprofloxacin . Nosocomial sinusitis requires coverage for gram-negative bacteria, including Pseudomonas aeruginosa . Immunocompromised patients, including those with acquired immunodeficiency syndrome, require treatment for fungal organisms . Decongestants are of unproven value . Referral for irrigation and surgical drainage is indicated for recurrent or recalcitrant sinusitis . Flexible endoscopy allows visualization and debridement of diseased tissue in cases of chronic sinusitis.

J Bacteriol, 1991 Dec, 173(24), 7781 - 9
Substitution of active-site His-223 in Pseudomonas aeruginosa elastase and expression of the mutated lasB alleles in Escherichia coli show evidence for autoproteolytic processing of proelastase; McIver K et al.; The neutral metalloprotease elastase is one of the major proteins secreted into the culture medium by many Pseudomonas aeruginosa strains . Encoded by the lasB gene, the 33-kDa elastase is initially synthesized as a 53-kDa preproenzyme which is processed to the mature form via a 51-kDa proelastase intermediate . To facilitate studies on proteolytic processing of elastase precursors and on secretion, we developed systems for overexpression of lasB in Escherichia coli under the control of the inducible T7 and tac promoters . Although the 51-kDa proelastase form was detectable in E . coli under inducible conditions, most of the elastase produced under these conditions was found in an enzymatically active 33-kDa form . The amino-terminal sequence of the first 15 amino acid residues of this 33-kDa elastase species was identical to that of the mature P . aeruginosa enzyme, suggesting that processing was autocatalytic . To test this possibility, the codon in lasB encoding His-223, a presumed active-site residue, was changed to encode Asp-223 (lasB1) and Tyr-223 (lasB2) . The effects of these mutations on enzyme activity and processing were examined . No proteolytic or elastolytic activities were detected in extracts of E . coli cells containing the lasB mutant alleles . Overexpression of the mutated lasB genes in E . coli resulted in the accumulation of the corresponding 51-kDa proelastase species . These were processed in vitro to the respective 33-kDa forms by incubation with exogenous purified elastase, without an increase in proteolytic activity . Molecular modeling studies suggest that the mutations have little or no effect on the conformation of the mutant elastases . In addition, wild-type elastase and the mutant proelastases were localized to the periplasm of E . coli . The present results confirm that His-223 is essential for elastase activity and provide evidence for autoproteolytic processing of proelastase.

Biophys J, 1991 Dec, 60(6), 1388 - 400
Lipid interaction of Pseudomonas aeruginosa exotoxin A . Acid-triggered permeabilization and aggregation of lipid vesicles; Menestrina G et al.; We have investigated the interaction of Pseudomonas exotoxin A with small unilamellar vesicles comprised of different phospholipids as a function of pH, toxin, and lipid concentration . We have found that this toxin induces vesicle permeabilization, as measured by the release of a fluorescent dye . Permeabilization is due to the formation of ion-conductive channels which we have directly observed in planar lipid bilayers . The toxin also produces vesicle aggregation, as indicated by an increase of the turbidity . Aggregation and permeabilization have completely different time course and extent upon toxin dose and lipid composition, thus suggesting that they are two independent events . Both time constants decrease by lowering the pH of the bulk phase or by introducing a negative lipid into the vesicles . Our results indicate that at least three steps are involved in the interaction of Pseudomonas exotoxin A with lipid vesicles . After protonation of one charged group the toxin becomes competent to bind to the surface of the vesicles . Binding is probably initiated by an electrostatic interaction because it is absolutely dependent on the presence of acidic phospholipids . Binding is a prerequisite for the subsequent insertion of the toxin into the lipid bilayer, with a special preference for phosphatidylglycerol-containing membranes, to form ionic channels . At high toxin and vesicle concentrations, bound toxin may also induce aggregation of the vesicles, particularly when phosphatidic acid is present in the lipid mixture . A quenching of the intrinsic tryptophan fluorescence of the protein, which is induced by lowering the pH of the solution, becomes more drastic in the presence of lipid vesicles . However, this further quenching takes so long that it cannot be a prerequisite to either vesicle permeabilization or aggregation . Pseudomonas exotoxin A shares many of these properties with other bacterial toxins like diphtheria and tetanus toxin.

J Clin Microbiol, 1991 Dec, 29(12), 2897 - 900
Restriction enzyme and Southern hybridization analyses of Pseudomonas aeruginosa strains from patients with cystic fibrosis; Loutit JS et al.; Conventional typing schemes for Pseudomonas aeruginosa may not discriminate strains . P . aeruginosa isolates from patients with cystic fibrosis were examined by restriction enzyme analysis and Southern hybridization . There was marked diversity of restriction enzyme analysis patterns among P . aeruginosa DNAs from cystic fibrosis isolates; however, sequential isolates obtained from individual patients showed very little variation over an 8-year period . DNA fragments from the alginate biosynthesis gene complex, the exotoxin A gene, and the elastase gene of P . aeruginosa were used in Southern hybridization analysis . The patterns of hybridization to the elastase and algD gene probes were highly conserved in all isolates, therefore, these DNA fragments are not useful in discriminating strains, in contrast to the exotoxin A gene probe.

Am J Dis Child, 1991 Dec, 145(12), 1433 - 8
Frequency of infections associated with implanted systems vs cuffed, tunneled Silastic venous catheters in patients with acute leukemia; Severien C et al.; A total of 75 central venous catheters were used for prolonged chemotherapy in 39 children with acute lymphocytic leukemia and 21 patients with acute myelocytic leukemia . Infection rates were 2.2 per 100 catheter days with the use of cuffed, tunneled, single-lumen Silastic catheters, 2.0 per 1000 catheter days with cuffed, tunneled, double-lumen Silastic catheters, and 0.5 per 1000 catheter days with the use of implanted venous access systems . Eighty-one percent of catheter sepsis episodes were successfully treated without removal of the catheter . All tunnel infections required withdrawal of the catheter for cure . The microorganisms were gram-positive bacteria in 15%, gram-negative bacteria in 7%, and fungi in 4% . Coagulase-negative staphylococci and Pseudomonas aeruginosa were the most commonly isolated organisms . Three of six fatal sepsis episodes were caused by disseminated fungal infections . We conclude that the use of intracorporeal venous catheter systems in patients with acute lymphocytic leukemia is associated with a lower infection rate than that with cuffed, tunneled Silastic single- or double-lumen catheters and that most septicemias can be cured with antimicrobial therapy without removal of the catheter.

Chest, 1991 Dec, 100(6), 1497 - 502
Temafloxacin compared with ciprofloxacin in mild to moderate lower respiratory tract infections in ambulatory patients . A multicenter, double-blind, randomized study; Chodosh S; The efficacy and safety of oral temafloxacin (600 mg) and ciprofloxacin (500 mg) twice daily for seven days were compared in patients with mild to moderate lower respiratory tract infections . Fifty-eight of 64 (91 percent) patients who received temafloxacin and 63 of 67 (94 percent) patients who received ciprofloxacin had clinical cure or improvement; bacteriologic cure occurred in 61 (95 percent) and 63 (94 percent), respectively . All 14 patients with pneumonia were clinically cured or improved and bacteriologically cured; 11 had complete resolution of roentgenographic evidence of pneumonia . Both quinolones eradicated most major respiratory pathogens . In the ciprofloxacin group, organisms persisted in three of seven Pseudomonas aeruginosa isolates and in one of eight Hemophilus parainfluenzae isolates; all these pathogens were eliminated with temafloxacin . Theophylline blood levels significantly increased by 25 percent in the ciprofloxacin group and decreased by 5 percent in the temafloxacin group . Adverse events, mostly dizziness, headache, and gastrointestinal effects, occurred in 43 percent of temafloxacin patients and in 31 percent of ciprofloxacin patients.

Lancet, 1991 Nov 16, 338(8777), 1236 - 7
Safety and immunogenicity of Pseudomonas aeruginosa conjugate A vaccine in cystic fibrosis; Schaad UB et al.; To assess the safety and immunogenicity of a Pseudomonas aeruginosa octavalent O-polysaccharide-toxin A conjugate vaccine, 22 patients (mean age 7 years) with cystic fibrosis who had no history of colonisation with P aeruginosa were immunised with the vaccine . Adverse reactions were mild and self-limiting . IgG antibody concentrations to all vaccine antigens were significantly raised after vaccination and remained so for 12 months . Immunisation produced opsonic and toxin A neutralising antibodies . A booster dose given at 12 months led to an anamnestic response . There was no significant change in clinical status after vaccination . Further work to assess efficacy in patients with cystic fibrosis can now be considered since our findings support the safety and immunogenicity of the vaccine.

Biochem Biophys Res Commun, 1991 Nov 14, 180(3), 1498 - 504
The carboxyl terminal amino acid residues of Pseudomonas aeruginosa exotoxin A involved in cell toxicity and pathogenesis, characterized by a neutralizing human monoclonal antibody; Ohtsuka H et al.; Human monoclonal antibody HI-1A4 (IgG3, lambda) neutralized a toxicity caused by pseudomonal exotoxin A (Ex-A) in cell culture and in vivo, and was effective in experimental Pseudomonas aeruginosa infections in mice . HI-1A4 inhibited an Ex-A catalyzed ADP-ribosylation of elongation factor 2 but did not inhibit an incorporation of toxin into a target cell at all . One molecule of HI-1A4 neutralized at least 2 molecules of Ex-A . HI-1A4 retained its binding activity at pH 4.0 . The epitope region for HI-1A4 was demonstrated to be a carboxyl terminal end of amino acid residues 591-613 of Ex-A . HI-1A4 might bind to Ex-A carboxyl terminal region outside a target cell, be incorporated into cells as a complex with Ex-A, and inhibit the intracellular function in which the carboxyl terminal part of Ex-A was involved, resulting in the interruption of intoxication of Ex-A.

J Bacteriol, 1991 Nov, 173(22), 7204 - 12
Cloning of a catabolite repression control (crc) gene from Pseudomonas aeruginosa, expression of the gene in Escherichia coli, and identification of the gene product in Pseudomonas aeruginosa; MacGregor CH et al.; Mutants which are defective in catabolite repression control (CRC) of multiple independently regulated catabolic pathways have been previously described . The mutations were mapped at 11 min on the Pseudomonas aeruginosa chromosome and designated crc . This report describes the cloning of a gene which restores normal CRC to these Crc- mutants in trans . The gene expressing this CRC activity was subcloned on a 2-kb piece of DNA . When this 2-kb fragment was placed in a plasmid behind a phage T7 promoter and transcribed by T7 RNA polymerase, a soluble protein with a molecular weight (MW) of about 30,000 was produced in Escherichia coli . A soluble protein of identical size was overproduced in a Crc- mutant when it contained the 2-kb fragment on a multicopy plasmid . This protein could not be detected in the mutant containing the vector without the 2-kb insert or with no plasmid . When a 0.3-kb AccI fragment was removed from the crc gene and replaced with a kanamycin resistance cassette, the interrupted crc gene no longer restored CRC to the mutant, and the mutant containing the interrupted gene no longer overproduced the 30,000-MW protein . Pools of intracellular cyclic AMP and the activities of adenylate cyclase and phosphodiesterase were measured in mutant and wild-type strains with and without a plasmid containing the crc gene . No consistent differences between any strains were found in any case . These results provide original evidence for a 30,000-MW protein encoded by crc+ that is required for wild-type CRC in P . aeruginosa and confirms earlier reports that the mode of CRC is cyclic AMP independent in this bacterium.

Kosm Biol Aviakosm Med, 1991 Nov-Dec, 25(6), 17 - 21
{Microbiological aspects of the environment of deep sea habitats}; Viktorov AN et al.; It is known that the hyperbaric environment facilitates selection of gram-negative microorganisms which acquire ecological predominance . From this point of view deep sea habitats can be regarded as a specific anthropotechnological niche for pathogenic microorganisms, particularly Pseudomonas aeruginosa A . aeruginosa colonization of the mucosa and skin of deep sea divers may result in infection manifestations which took place in chamber experiments when test subjects showed otitis externa and when virulent strains were isolated . It was demonstrated that the basic reservoir of P . aeruginosa was the water supply system . Hence, development of a reliable method for its disinfection should be of highest priority . One of the potential methods is SHF treatment . Another important approach is personal hygiene procedures preventing skin and mucosa contamination with potentially pathogenic microorganisms and procedures for increasing colonization resistance of divers with the aid of eubiotic therapy.

Am Rev Respir Dis, 1991 Nov, 144(5), 1147 - 52
Role of mechanical injury on airway surface in the pathogenesis of Pseudomonas aeruginosa; Yamaguchi T et al.; In this study, bacterial attachment to rat tracheal surface was measured using three nonmucoid strains of Pseudomonas aeruginosa and bacterial growth after binding to tracheal surface was also tested . Brush injury on tracheal surface significantly increased bacterial attachment (1,190 to 1,600%); bacteria binding to brush-injured sites grew more rapidly than either nonbinding bacteria or those on intact trachea . A partial characterization of the binding sites for P . aeruginosa on either intact or injured tracheal surface also was performed . Treatment of injured tracheal surface with metaperiodate significantly inhibited attachment of P . aeruginosa, but trypsin treatment did not . In contrast, neither reagent had any effects on bacterial attachment to intact tracheal surface . These results suggest that brush injury on tracheal surface produces new binding sites as a receptor for P . aeruginosa, and that this receptor has carbohydrates as important components and that it is not a protein receptor . In addition, in order to determine what the dominant sugar of this receptor was, we tested the inhibition of bacterial attachment with monosaccharide, neuraminidase, and lectin . Treatment of bacteria with N-acetylneuraminic acid (NANA) dramatically inhibited bacterial attachment to injured trachea . However, NANA also inhibited the growth of this organism . Moreover, neither neuraminidase nor lectin data suggested that the dominant sugar of the receptor was NANA . Our data go so far as to confirm that the major component of the receptor of nonmucoid strains of P . aeruginosa on brush-injured trachea is carbohydrates; it is still unclear what kind of sugar is the dominant component of the receptor.(ABSTRACT TRUNCATED AT 250 WORDS)

J Infect Dis, 1991 Nov, 164(5), 917 - 21
Oral aminoglycoside and ofloxacin therapy in the prevention of gram-negative sepsis after irradiation; Brook I et al.; To investigate whether oral gentamicin or ofloxacin therapy protects against gram-negative sepsis after irradiation, B6D2F1 mice were exposed to 7.5 Gy of radiation from 60Co, infected with 10(7) Pseudomonas aeruginosa or Klebsiella pneumoniae orally 3 days after irradiation, and treated with oral (15 mg/kg/day) or intramuscular (im; 7.5 mg/kg/day) gentamicin or oral (40 mg/kg/day) ofloxacin . For P . aeruginosa, gentamicin therapy was started orally 10 and 24 h and im 24 h after inoculation . For K . pneumoniae, gentamicin was started orally 24, 48, and 72 h and im 24 h after inoculation; ofloxacin was started 24 h after inoculation . Mice that received oral gentamicin early (10 h for P . aeruginosa, 24 h for K . pneumoniae), im gentamicin, or oral ofloxacin showed significantly (P less than .05) reduced colonization, translocation, and mortality compared with mice that received oral gentamicin late . These data support the use of selective antimicrobial therapy to reduce colonization, translocation, and mortality from gram-negative bacteria in irradiated animals.

J Bacteriol, 1991 Nov, 173(21), 6798 - 806
The agmR gene, an environmentally responsive gene, complements defective glpR, which encodes the putative activator for glycerol metabolism in Pseudomonas aeruginosa; Schweizer HP; The genes for the peripheral glycerol carbon metabolic pathway (glp) in Pseudomonas aeruginosa are postulated to be positively regulated by GlpR . A gene complementing the glpR2 allele, affecting expression of the putative activator, was cloned by a bacteriophage mini-D3112-based in vivo cloning method . Mini-D3112 replicons were isolated by transfecting glpR2 strain PRP406 and selecting clones able to grow on minimal medium containing glycerol as the sole carbon and energy source . Preliminary biochemical characterization indicated that the cloned activator gene for glycerol metabolism (agmR) may not be allelic to glpR . Restriction analysis and recloning of DNA fragments located the agmR gene to a 2.3-kb EcoRV-SstI DNA fragment . In a T7 RNA polymerase expression system, a single 26,000-Da protein was expressed from this DNA fragment . The amino acid sequence of this protein, deduced from the nucleotide sequence reported here, demonstrates its homology to the effector (or regulator) proteins of the environmentally responsive two-component regulators . The carboxy-terminal region of AgmR contains a possible helix-turn-helix DNA-binding motif and resembles sequences found in transcriptional regulators of the LuxR family.

J Bacteriol, 1991 Nov, 173(21), 6657 - 64
Pseudomonas aeruginosa outer membrane protein OprH: expression from the cloned gene and function in EDTA and gentamicin resistance; Bell A et al.; Overexpression of major outer membrane protein OprH of Pseudomonas aeruginosa as a result of mutation (in strain H181) or adaptation to low Mg2+ concentrations (in parent strain H103) is accompanied by increased resistance to polymyxin B, gentamicin, and EDTA . A 2.8-kb EcoRI fragment containing the oprH gene was subcloned into several different expression plasmids in Escherichia coli . These experiments showed that significant levels of OprH could be produced from a promoter on the EcoRI fragment; that the cloned oprH gene was not regulated by Mg2+ deficiency; that there were no differences in the expression of OprH in any construction, regardless of whether the gene from strain H103 or its OprH-overexpressing, polymyxin B-resistant derivative, strain H181, was used; and that overexpression of OprH in E . coli to the level observed in P . aeruginosa H181 did not result in a resistance phenotype . These results favored the conclusion that the mutation in strain H181 was a regulatory rather than a promoter mutation . The oprH gene was cloned behind the benzoate-inducible pm promoter in plasmid pGB25 and transferred to P . aeruginosa H103 . Overexpression of OprH from the cloned gene in H103/pGB25 resulted in EDTA resistance but not polymyxin B resistance . This result suggested that another factor, possibly lipopolysaccharide, was affected by the mutation in strain H181 . Consistent with this suggestion was the demonstration that mutants of strain H181 with alterations in lipopolysaccharide had reverted to wild-type polymyxin B susceptibility but had unaltered gentamicin and EDTA resistance . These data were consistent with the hypothesis that OprH replaces outer membrane-stabilizing divalent cations.

Infect Immun, 1991 Nov, 59(11), 4283 - 5
Arylneuraminidase activity of Pseudomonas aeruginosa does not degrade natural substrates such as human respiratory mucins; Scharfman A et al.; The culture supernatant from a single Pseudomonas aeruginosa strain has been reported to show neuraminidase activity, leading to the speculation that this bacterium may use this enzyme as a virulence factor to act on host macromolecules . In order to extend this finding, we have examined the activity of concentrated P . aeruginosa culture supernatants and cells on synthetic and natural substrates containing sialic acid, such as human respiratory mucins . Four P . aeruginosa strains showed some activity on the synthetic substrate 4-methylumbelliferyl-alpha-D-N-acetylneuraminic acid but failed to liberate N-acetylneuraminic acid from six different natural substrates . Attempts to induce enzyme production by use of human respiratory mucins in the culture medium were also unsuccessful . The supernatants also showed N-acetyl-beta-D-glucosaminidase-like activity on a synthetic substrate but did not liberate N-acetylhexosamines from natural substrates . We conclude that the neuraminidase-like activity observed in P . aeruginosa can be defined as an arylneuraminidase and that the possession of a neuraminidase active on natural substrates is not a common attribute of P . aeruginosa strains.

Infect Immun, 1991 Nov, 59(11), 4259 - 62
ADP-ribosylation of p21ras and related proteins by Pseudomonas aeruginosa exoenzyme S; Coburn J et al.; Pseudomonas aeruginosa exoenzyme S ADP-ribosylates p21ras and several related proteins . ADP-ribosylation of p21ras does not alter interactions with guanine nucleotides . The ras-related GTP-binding proteins, including Rab3, Rab4, Ral, Rap1A, and Rap2, are also substrates; given these results, we propose a model for the role of exoenzyme S in pathogenesis.

Infect Immun, 1991 Nov, 59(11), 4193 - 200
Comparison of granule proteins from human polymorphonuclear leukocytes which are bactericidal toward Pseudomonas aeruginosa; Wasiluk KR et al.; Killing of Pseudomonas aeruginosa by a 55-kDa bactericidal protein (BP 55), a 30-kDa protein (BP 30), cathepsin G, elastase, and proteinase 3 has been compared . P . aeruginosa was resistant to killing by elastase and proteinase 3 . BP 55 at a 50% lethal dose (LD50) of 0.23 micrograms of protein per 5 x 10(6) bacteria per ml killed P . aeruginosa and was far more active than BP 30 and cathepsin G . The LD50s of BP 30 and cathepsin G were 16.9 and 28.3 micrograms of protein per 5 x 10(6) bacteria per ml, respectively . Preincubation of BP 55 or BP 30 with lipopolysaccharide (LPS) from P . aeruginosa inhibited bactericidal activity . The N-terminal amino acid sequence of BP 55 and BP 30 revealed no relationship between the two proteins . However, a monoclonal antibody (AHN-15) reacted with both proteins by Western immunoblot . The bactericidal activity of cathepsin G toward P . aeruginosa appeared to be dependent on the availability of the active site of the enzyme; bactericidal activity was inhibited by phenylmethylsulfonyl fluoride (PMSF) and by the specific cathepsin G inhibitor, Z-Gly-Leu-Phe-CH2Cl . The enzyme and bactericidal activities of cathepsin G were also inhibited by LPS from P . aeruginosa . LPS from P . aeruginosa was shown to be a competitive inhibitor of the enzyme activity of cathepsin G . Elastase enzyme activity was also inhibited noncompetitively by LPS, but the enzyme was not bactericidal . We have concluded that all three bactericidal proteins (BP 55, BP 30, and cathepsin G) may bind to the LPS of the outer membrane of P . aeruginosa . It appears that the enzyme active site must be available for cathepsin G to kill P . aeruginosa and that the active site may be involved in the binding of cathepsin G to P . aeruginosa.

Gastroenterology, 1991 Nov, 101(5), 1374 - 81
Risk factors for septicemia following endoscopic biliary stenting; Motte S et al.; The purpose of this study was to identify patients who were more likely to experience septicemia after endoscopic biliary drainage . In an attempt to determine the relative importance of each risk factor and their possible interdependancy to more precisely identify high-risk patients and to deduce some guidelines for prevention, a discriminant regression analysis of risk factors for septicemia was used . Clinical, biological, and radiological data of 34 consecutive patients who experienced septicemia within 3 days after endoscopic biliary stenting were reviewed retrospectively and compared with data of a group of 71 patients without any septic complication . If only data available before the procedure were used in the discriminant analysis, prior cholangitis and leucocytosis appeared as significant risk factors, but the linear combination of these data could not predict septicemia in 50% of cases . When information concerning the quality of drainage after the procedure was introduced into the analysis, 91% of the septicemic patients were identified, and other expected risk factors such as the nature of the stricture, the type of drainage, or prior cholangitis and leukocytosis had no or marginal predictive values . Patients referred from centers where duodenoscopes might have been poorly disinfected appeared to be at higher risk for Pseudomonas aeruginosa septicemia . These results emphasize the crucial role of the quality of drainage as a risk for septicemia . Regarding the prevention of infection, it is concluded from this study that (a) pure diagnostic endoscopic retrograde cholangiopancreatography should be avoided in obstructed patients if drainage cannot be performed during the same procedure; (b) drainage should be as complete as possible; (c) antibiotics should be administered before ERCP to every patient with suspected obstructive jaundice and should cover P . aeruginosa if local epidemiological data suggest that there is a problem with disinfection of the endoscopes; and (d) the quality of drainage should guide the duration of antibiotic prophylaxis.

Infect Immun, 1991 Nov, 59(11), 3997 - 4000
Siderophore presence in sputa of cystic fibrosis patients; Haas B et al.; Sputum samples from the lungs of cystic fibrosis patients harboring Pseudomonas aeruginosa infections were collected and examined for the presence of the siderophore pyoverdine . Fluorescence quenching, due to the addition of ferric ion, as well as column and thin-layer chromatography results indicated that all samples contained the siderophore . Six samples furnished sufficient material after purification to allow us to obtain visible absorbance spectra . These spectra were characteristic of the ferrated analog of the P . aeruginosa pyoverdine, that is, ferripyoverdine, and in all cases they indicated a degree of ferration in excess of 50% . P . aeruginosa in the cystic fibrosis lung is thus iron stressed and responds by synthesizing pyoverdine, which subsequently binds ferric ion.

FEMS Microbiol Immunol, 1991 Nov, 3(6), 321 - 5
Antibodies against the common polysaccharide and protein protective antigens of Pseudomonas aeruginosa in normal blood donors; Makarenko TA et al.; Screening of normal plasma obtained from 172 blood donors from the Helsinki area and from 46 blood donors from the Moscow area was performed in order to reveal 'natural' antibodies to the common polysaccharide (rhamnan) and protein antigens of P . aeruginosa . Antibodies were detected by ELISA . Among blood donors from the Helsinki area high titres of antibodies to the protein antigens were detected in 42 active blood donors (24.4%) and very high titres in nine (5.3%) highly-active blood donors, whereas in the Moscow area in 15 (34.9%) and in one case (2.3%), respectively . Antibodies to the common polysaccharide antigen were determined in the Helsinki area in 23 active blood donors (13.4%) and in one (0.5%) highly active blood donor, whereas in the Moscow area in four active blood donors (8.6%) . The plasma contained both polysaccharide and anti-protein antibodies . The level of antibodies to the polysaccharide antigen was lower than the level of antibodies to the protein antigens . There was no statistically significant difference between the corresponding values of blood donor groups from the Helsinki and Moscow areas.

Izv Akad Nauk SSSR Biol, 1991 Nov-Dec, (6), 943 - 9
{A microbiological examination of the skin and vaginal mucus of Amazon River freshwater dolphins (Inia geoffrensis) in relation to an assessment of the physiological state of the animals}; Ushakova NA; There is a definite relation between the state of dolphin's health and the abundance of bacterial associations developing on the skin surface around the dorsal fin . The disease was accompanied by an increase in bacterium amount more than fourfold due to the enhancement of staphylococcus and pseudomonad number . The development of dystrophy in the animal resulted in a threefold decrease in bacterium number . Pseudomonas aeruginosa dominated in this case . In the vaginal mucose of female, the development of bacteria had an oscillatory character and was correlated with the dynamics of leukocyte number against the background of morphologically diverse epithelial cells discharged in different periods of observation . Periods of the abundant bacterium development were connected with the cyclic recurrence of sexual (estrous) processes in the female organism.

Antimicrob Agents Chemother, 1991 Nov, 35(11), 2312 - 7
Comparison of cefepime, cefpirome, and cefaclidine binding affinities for penicillin-binding proteins in Escherichia coli K-12 and Pseudomonas aeruginosa SC8329; Pucci MJ et al.; The relative binding affinities of the extended-spectrum cephalosporins cefepime, cefpirome, and cefaclidine for the penicillin-binding proteins (PBPs) of Escherichia coli K-12 and Pseudomonas aeruginosa SC8329 were determined . Affinities were calculated from competition experiments between these antibiotics and {3H}benzylpenicillin in isolated membrane preparations . The concentrations which reduced binding to a PBP by 50% (IC50s) were determined . For E . coli, all three antibiotics displayed good PBP 3 binding (IC50s of 0.5 microgram/ml or less), and MICs roughly correlated with these values . Cefepime had a greater than 20-fold-lower IC50 for PBP 2 of E . coli than the other antibiotics . For P . aeruginosa, all of the antibiotics bound poorly (greater than 25 micrograms/ml) to PBP 2 but showed excellent pseudomonal (less than 0.0025 microgram/ml) PBP 3 binding . No correlations were seen between IC50s and MICs for P . aeruginosa . Despite differences in PBP binding, cefepime, cefpirome, and cefaclidine all displayed similar bactericidal activity for E . coli K-12 over the initial 3 h after antibiotic addition . All three caused E . coli to form filaments at values close to the MICs . In addition, cefepime induced "bleb" formation along the filaments at concentrations greater than 10x the MIC.

Genetika, 1991 Nov, 27(11), 1904 - 11
{Isolation and characterization of Pseudomonas aeruginosa bacteriophage phikF77 mutants}; Kulakov LA et al.; It was found that phage phi kF77 is resistant to all known Pseudomonas aeruginosa restriction systems . Three types of mutants (dc-) which were unable to grow on different restrictive strains were isolated . All of them belong to one complementation group . Some of these mutations affected also the number of nicks in phage phi kF77 DNA and increased phage resistance to temperature treatment . It may be supposed that genes responsible for antirestriction mechanisms and introduction of nicks into DNA are connected in definite way.

Antibiot Khimioter, 1991 Nov, 36(11), 21 - 4
{Comparative study on growth kinetics of organisms causing purulent infections in the presence of ofloxacin and ciprofloxacin}; Skala LZ; The comparative study of the antimicrobial effect of ofloxacin and ciprofloxacin on the in vitro kinetic models of the pathogen growth showed that ciprofloxacin was more active against Staphylococcus aureus and Pseudomonas aeruginosa . The post-antibiotic effect depended of the drug concentration and period of the pathogen content with ofloxacin and ciprofloxacin . With respect to the both pathogens, the post-antibiotic effect of ciprofloxacin was more pronounced.

Antibiot Khimioter, 1991 Nov, 36(11), 17 - 21
{Various methods to assay carbenicillin activity against Pseudomonas aeruginosa}; Litovchenko PP et al.; It was shown that the cultures of Pseudomonas aeruginosa were sensitive to 75-100 micrograms/ml and resistant to 25-50 micrograms/ml of carbenicillin when tested by the method of serial dilutions in the synthetic medium developed by the authors and in Jorgensen's medium . The cultures were incubated for 4 and 16 hours, respectively . The data did not confirm the resistance of the cultures to 25-75 and 100 micrograms/ml carbenicillin when it was determined with the serial dilution method in Pal's medium and the disk diffusion method, respectively . The advantages of the medium developed by the authors for testing P . aeruginosa sensitivity to carbenicillin are discussed.

Mol Microbiol, 1991 Nov, 5(11), 2641 - 7
Export of infectious particles by Escherichia coli transfected with the RF DNA of Pf1, a virus of Pseudomonas aeruginosa strain K; Kostrikis LG et al.; Pf1 is a filamentous, single-stranded DNA virus that has Pseudomonas aeruginosa (strain K) as host . It is the longest of the filamentous bacterial viruses, and the DNA within it has the most extended conformation known . Pf1 virus cannot infect Escherichia coli (strain MM294) cells, but when these cells are transfected with the double-stranded replicative form of Pf1 DNA (RF DNA, 7.35 kb), they export low levels of infectious particles that create plaques on lawns of P . aeruginosa . Several different structural species, at least two of which are infectious, are exported . One of them, called Epf1, has virtually the same structure as Pf1, but the amount of Epf1 exported by E . coli is 10(4) lower than the amount of Pf1 exported by P . aeruginosa . The results imply that host factors affect not only the efficiency of virus assembly and export, but also the actual structures of the species exported.

Mol Microbiol, 1991 Nov, 5(11), 2581 - 7
Pseudomonad replication origins: a paradigm for bacterial origins?
Smith DW, Yee TW, Baird C, Krishnapillai V.
Structural features of three analysed bacterial DNA replication origin classes (six enteric origins, three pseudomonad origins, and the Bacillus subtilis origin region) are compared in order to deduce characteristics common to all bacterial origins and characteristics that distinguish the three origin classes . The two Pseudomonas aeruginosa origins are shown to map within 10 kb of each other, and correlations are drawn with four potential origin regions in B . subtilis . The enteric origin class is further distinguished from the other two classes by its genetic organization, the presence of GATC sites, and the role of Dam methylation in enteric initiation . The pseudomonad origin class has the most features that are common to all of these bacterial origins, and hence may be the paradigm bacterial origin class.

J Burn Care Rehabil, 1991 Nov-Dec, 12(6), 533 - 9
Cultured epithelial autografts: three years of clinical experience with eighteen patients; Clugston PA et al.; Eighteen patients with major burns (mean total body surface area burned was 49% and mean total body surface area with full-thickness burns was 38%) had cultured epithelial autografts applied to 2% to 35% of the body surface area . In six patients successful "take" of greater than 65% occurred, and in 12 patients less than 40% "take" occurred . Most wounds underwent early excision to subcutaneous fat or fascia, and the wounds of 16 patients had been treated previously with homograft . Cultured epithelial autografts were covered with either single or multilayered dressings . Perioperative wound cultures showed that all patients had microorganisms, and appropriate perioperative antibiotic coverage of Staphylococcus epidermidis and Pseudomonas aeruginosa was noted less frequently in the poor take group, which may have influenced subsequent cultured epithelial allograft take . Adherence and stability of cultured epithelial allografts lag behind adherence and stability of meshed split-thickness autograft . The anterior trunk and thighs are the best recipient sites . The number of autograft harvests that were required to close wounds and the length of hospital stay were not significantly decreased by the use of cultured epithelial allografts as compared with comparable full-thickness burns that were treated previously without cultured epithelial allografts . Presently, grafting with cultured epithelial allografts is an adjunct but not an alternative to conventional burn-wound coverage with split-thickness autograft, because engraftment is inconsistent.

Endoscopy, 1991 Nov, 23(6), 325 - 7
Frequency and spectrum of microorganisms isolated from biopsy specimens in chronic colitis; Horing E et al.; In 109 patients with chronic diarrhea colonic biopsies were examined for the presence of specific microorganisms . A positive result was obtained in 48% of patients with ulcerative colitis, 50% with Crohn's disease, 21% with non-specific colitis and 36% with non-specific proctitis . Chlamydiae were found most frequently in all groups . Obligate enteropathogenic bacteria were isolated in only three cases of nonspecific colitis . Of the facultatively enteropathogenic organisms Klebsiella and Pseudomonas aeruginosa were isolated in 31% and 24%, respectively, of patients with ulcerative colitis, in 21% and 7% of patients with Crohn's disease, and in 10% and 6% of patients with non-specific colitis . Whereas chlamydial proctitis is a well-known disease, the results of this study point also to a possible pathogenic role of chlamydiae in the proximal colon . Facultatively enteropathogenic organisms causing acute diarrhea might have aetiologic relevance in some cases of chronic non-specific colitis.

DICP, 1991 Nov, 25(11), 1168 - 70
Toxicity of colistin in cystic fibrosis patients; Bosso JA et al.; Pulmonary exacerbations of cystic fibrosis associated with strains of Pseudomonas aeruginosa that are resistant to multiple antibiotics are becoming increasingly common . The search for treatment alternatives continues and may include the reexamination of older antibiotics . Colistin sulfate is a polypeptide antibiotic with good activity against P . aeruginosa . Although its use was largely discontinued in the early 1970s because of reports of frequent renal and neurologic toxicity, intravenous colistin is often prescribed at our institution for patients with P . aeruginosa resistant to multiple-drug therapy . We prospectively monitored 19 patients during 21 courses of colistin therapy to identify the character and incidence of this agent's toxicity . Only one case of renal toxicity occurred . Six cases of neurotoxicity occurred, which were characterized by perioral paresthesia, ataxia, or both . The rate of intolerable renal adverse effects secondary to colistin therapy was appreciably lower among these patients than that reported previously for other patients . It appears that intravenous colistin can be considered for cystic fibrosis patients with strains of P . aeruginosa that are resistant to more commonly used antibiotics.

Bioorg Khim, 1991 Nov, 17(11), 1534 - 49
{Trityl-cyanoethylidene condensation of azidosaccharide derivatives as a route to hexosaminoglycans . Synthesis of the O-antigenic polysaccharide of Pseudomonas aeruginosa X (Meitert)}; Tsvetkov IuE et al.; Derivatives of azidosugars were shown to be stable under conditions of trityl-cyanoethylidene condensation . Tritylated 1,2-O-(1-cyano)ethylidene derivative of 2-azido-2-deoxy-beta-D-mannopyranosyl-(1----4)-L-rhamnopyranose was used as a starting material for the synthesis of {----3)-beta-D-ManNAc-(1----4)-alpha-L-Rha-(1----}n, the O-specific polysaccharide of Pseudomonas aeruginosa X (Meitert).

Biol Chem Hoppe Seyler, 1991 Nov, 372(11), 963 - 70
Different susceptibility of elastase inhibitors to inactivation by proteinases from Staphylococcus aureus and Pseudomonas aeruginosa; Sponer M et al.; Neutrophil elastase is thought to contribute to the lung pathology in patients with cystic fibrosis (CF) . Therefore, intrapulmonary application of elastase inhibitors might be beneficial for these patients . Inactivation of such inhibitors by bacterial proteinases, however, is an important consideration in this therapy . We studied the effects of Staphylococcus aureus proteinase (STAP) and Pseudomonas aeruginosa elastase (PsE) on native (alpha 1-AT) and recombinant (rAAT) alpha 1-antitrypsin, recombinant secretory leukocyte proteinase inhibitor (rSLPI) and the leech inhibitor eglin C . All inhibitors were inactivated by these bacterial proteinases showing pronounced differences in their susceptibilities to proteolytic cleavage . Comparing the turnover rate (mol of inhibitor inactivated by one mol bacterial proteinase/min), rAAT and alpha 1-AT were approximately 20,000-fold more susceptible to STAP than rSLPI and 50,000-fold more susceptible than eglin C . Pseudomonas aeruginosa elastase inactivated all inhibitors more rapidly than STAP . rAAT and alpha 1-AT were 13-fold and 17,000-fold more susceptible than rSLPI and eglin C, respectively . Incubation of the rAAT-elastase complex with equimolar amounts of STAP did not result in release of elastase activity . Upon simultaneous addition of STAP and leukocyte elastase to rAAT, there was undisturbed elastase inhibition indicating that complex formation with elastase proceeded at a faster rate than inactivation of rAAT by the bacterial proteinase . From these results of inactivation in vitro and considering the immunogenic potential of the inhibitors studied here, we conclude that rSLPI may be the appropriate choice for anti-elastase therapy in CF.

Ophthalmology, 1991 Nov, 98(11), 1693 - 7
Treatment of experimental Pseudomonas keratitis with cyclo-oxygenase and lipoxygenase inhibitors; Moreira H et al.; The role of metabolites of arachidonic acid in experimental Pseudomonas keratitis was studied using inhibitors of arachidonic acid metabolism . Nordihydroguaiaretic acid 1%, which inhibits predominantly the lipoxygenase pathway, and flurbiprofen 0.03%, which inhibits predominantly the cyclo-oxygenase pathway were administered topically to rabbit eyes after intrastromal injection of Pseudomonas aeruginosa . Levels of the cyclo-oxygenase product prostaglandin E2 (PGE2) and the lipoxygenase product leukotriene B4 (LTB4) were measured, and the number of ulcers that had progressed to descemetocele formation by 24 hours was determined . Corneal ulceration was accelerated by flurbiprofen, but nordihydroguaiaretic acid limited the flurbiprofen-induced worsening . The use of flurbiprofen was associated with decreased levels of PGE2 and a relative increase in LTB4, a potent chemoattractant and activator of polymorphonuclear leukocytes . These results suggest that inhibition of the cyclo-oxygenase pathway may be contraindicated in Pseudomonas keratitis; inhibition of lipoxygenase can prevent this worsening of the keratitis.

Gene, 1991 Oct 30, 107(1), 145 - 8
Sequence of hrdB, an essential gene encoding sigma-like transcription factor of Streptomyces coelicolor A3(2): homology to principal sigma factors; Shiina T et al.; The complete nucleotide sequence of the hrdB gene, an essential gene of Streptomyces coelicolor A3(2), indicates the presence of an open reading frame encoding a putative polypeptide of 442 amino acid (aa) residues with an Mr of 48,412 . The principal sigma-like transcriptional factor of S . coelicolor (HrdB) protein showed an extensive aa sequence homology with the known principal sigma factors of Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa and Myxococcus xanthus . The degree of sequence similarity between HrdB protein and the known principal sigma factors was distinct from that observed between the principal sigma factors and the alternative (minor) sigma factors . Essentially all of the functional domains proposed for the principal sigma factor of E . coli were conserved in HrdB protein . The putative sigma factor, HrdB, like that of B . subtilis had a short internal nonconserved region, which might be characteristic of Gram+ species.

Gene, 1991 Oct 30, 107(1), 1 - 10
Nucleotide sequence and expression of the algE gene involved in alginate biosynthesis by Pseudomonas aeruginosa; Chu L et al.; Alginate (Alg), a random polymer of mannuronic acid and glucuronic acid residues, is synthesized and secreted by Pseudomonas aeruginosa primarily during its infection of the lungs of cystic fibrosis patients . The molecular biology and biochemistry of the enzymatic steps leading to the production of the Alg precursor GDP-mannuronic acid have been elucidated, but the mechanism of polymer formation and export of Alg are not understood . We report the nucleotide sequence of a 2.4-kb DNA fragment containing the algE gene, previously designated alg76, encoding the AlgE protein (Mr 54,361) that is believed to be involved in these late steps of Alg biosynthesis . Expression of algE appears to occur from its own promoter . The promoter region contains several direct and inverted repeat sequences and shares structural similarity with promoters of several other alg genes from P . aeruginosa . In addition, the AlgE protein was overproduced from the tac promoter in P . aeruginosa . N-terminal amino acid sequence analysis showed that the polypeptide contains a signal peptide which is cleaved to form the mature protein during AlgE export from the cell cytoplasm.

Presse Med, 1991 Oct 19, 20(33), 1592 - 4
{Resistance of hospital flora to imipenem . Experience in two intensive care units}; Hamon-Poupinel V et al.; Imipenem is a beta-lactam antibiotic active against most Gram-negative bacilli . Between July 1, 1987 and September 30, 1989 (9 semesters), the activity of imipenem against 6 micro-organisms was tested in two intensive care units attached to the university hospital of Caen (Normandy) . During the same period, the consumption of imipenem was evaluated from the number of vials drawn by each of these two units from the central pharmacy . Imipenem was found to be 100 percent effective against 5 of the 6 micro-organisms tested, but transient falls in sensitivity and an increase in imipenem consumption were observed when Pseudomonas aeruginosa was the pathogen . The most probable cause of these transient decreases of imipenem activity against Ps . aeruginosa was the existence of a resistant strain which showed a protein abnormality in its outer membrane by temporary selection pressure.

J Mol Biol, 1991 Oct 5, 221(3), 765 - 72
Crystal structure analysis of oxidized Pseudomonas aeruginosa azurin at pH 5.5 and pH 9.0 . A pH-induced conformational transition involves a peptide bond flip; Nar H et al.; The X-ray crystal structure of recombinant wild-type azurin from Pseudomonas aeruginosa was determined by difference Fourier techniques using phases derived from the structure of the mutant His35Leu . Two data sets were collected from a single crystal of oxidized azurin soaked in mother liquor buffered at pH 5.5 and pH 9.0, respectively . Both data sets extend to 1.93 A resolution . The two pH forms were refined independently to crystallographic R-factors of 17.6% (pH 5.5) and 17.5% (pH 9.0) . The conformational transition previously attributed to the protonation/deprotonation of residue His35 (pKa(red) = 7.3, pKa(ox) = 6.2), which lies in a crevice of the protein close to the copper binding site, involves a concomitant Pro36-Gly37 main-chain peptide bond flip . At the lower pH, the protonated imidazole N delta 1 of His35 forms a strong hydrogen bond with the carbonyl oxygen from Pro36, while at alkaline pH the deprotonated N delta 1 acts as an acceptor of a weak hydrogen bond from HN Gly37 . The structure of the remainder of the azurin molecule, including the copper binding site, is not significantly affected by this transition.

Mol Gen Genet, 1991 Oct, 229(3), 334 - 40
Nucleotide sequence of genes hrdA, hrdC, and hrdD from Streptomyces coelicolor A3(2) having similarity to rpoD genes; Tanaka K et al.; The complete nucleotide sequences were determined of hrdA, hrdC, and hrdD from Streptomyces coelicolor A3(2) . They indicate the presence of a single open reading frame in each gene coding for polypeptides of 396 (43,747 daltons), 339 (38,173 daltons), and 332 amino acid residues (37,190 daltons), respectively . These amino acid sequences revealed extensive similarities with the principal sigma factors of Bacillus subtilis, Escherichia coli, Mxyococcus xanthus, Pseudomonas aeruginosa, and also the katF gene product of E . coli . Besides the highly conserved amino acid residues in the "rpoD box" region, alignment of hrd gene products and the known principal sigma factors and sigma-related factors allowed us to postulate a common basic structure for the principal sigma type factors as distinct from the alternative sigma factors.

J Clin Microbiol, 1991 Oct, 29(10), 2151 - 7
Heterogeneity, persistence, and distribution of Pseudomonas aeruginosa genotypes in cystic fibrosis patients; Fegan M et al.; A collection of 222 isolates of Pseudomonas aeruginosa was obtained from the respiratory tract of 16 patients with cystic fibrosis over a 4- to 9-month period . Fourteen of these patients were unrelated, while the remaining two were siblings . Isolates were typed by conventional pyocin typing and also by the use of a DNA probe containing 741 bp immediately upstream of the exotoxin A structural gene and the initial 732 bp of the exotoxin A structural gene . By pyocin typing, 69% (11 of 16) of the patients were shown to harbor a single type that persisted in the lung throughout the study . By genotyping (DNA probe typing), all but three patients (13 of 16, 81%) harbored a single persistent genotype in their lungs . Six patients other than the sibling pair (6 of 14, 43%) shared a common genotype in their lungs as judged by DNA probing, and the pyocin type of these isolates was also identical . In four of these six patients, the shared genotype was also the persistent genotype . The sibling pair studied also carried a common genotype in their lungs as indicated by DNA probing, even though the pyocin type of these isolates varied . Results presented suggest that the majority of patients harbor a persistent strain in their lungs and that cross-colonization may occur.

APMIS, 1991 Oct, 99(10), 925 - 30
Morphology of Pseudomonas aeruginosa phages from the sputum of cystic fibrosis patients and from the phage typing set . An electron microscopy study; Ojeniyi B et al.; Sixteen phage suspensions isolated from the sputum of sixteen cystic fibrosis patients and five phages from the present phage typing set were studied by electron microscopy . All sputum samples contained at least one type of bacteriophage (range: 1-4) which could be classified by the morphology and dimensions of the virion . All phages isolated from sputum as well as the four typing phages were tailed phages . The clinical phages belonged either to the Myoviridae, Siphoviridae or Podoviridae family . The four typing phages belonged to the Myoviridae family . The detection of the presence of tailed phages in sputum further supports the prevailing theory that phages play a role in the phenotypical change of Pseudomonas aeruginosa during the chronic lung infection of cystic fibrosis patients, since only tailed phages are known to be temporate and thus mediate transduction and conversion.

Arch Ophthalmol, 1991 Oct, 109(10), 1447 - 8
Adherence of Pseudomonas aeruginosa to rigid gas-permeable contact lenses; Miller MJ et al.; We examined the adherence of a human corneal isolate of Pseudomonas aeruginosa to unused rigid gas-permeable and hydrogel contact lenses . Adherence to rigid gas-permeable lenses was greater than the adherence to hydrogels . The lower incidence of microbial keratitis associated with rigid gas-permeable lenses, as compared with hydrogel lenses, may be attributed to the more rigorous cleaning and disinfection possible for rigid gas-permeable lenses and/or patient noncompliance with complicated disinfection systems used with hydrogel lenses.

J Bacteriol, 1991 Oct, 173(19), 6153 - 8
Detection of elastase production in Escherichia coli with the elastase structural gene from several non-elastase-producing strains of Pseudomonas aeruginosa; Tanaka E et al.; The elastase structural gene from Pseudomonas aeruginosa IFO 3455 has been cloned and sequenced . Using this gene as a probe, we cloned the DNA fragments (pEL3080R, pEL10, and pEL103R) of the elastase gene from non-elastase-producing strains (P . aeruginosa IFO 3080, N-10, and PA103 respectively) . These three Pseudomonas strains showed no detectable levels of elastase antigenicity by Western blotting (immunoblotting) or by elastase activity . When elastase structural genes about 8 kb in length were cloned into pUC18, an Escherichia coli expression vector, we were able to detect both elastase antigenicity and elastolytic activity in two bacterial clones (E . coli pEL10 and E . coli pEL103R) . However, neither elastolytic activity nor elastase antigenicity was detected in the E . coli pEL3080R clone, although elastase mRNA was observed . The partial restriction map determined with several restriction enzymes of these three structural genes corresponded to that of P . aeruginosa IFO 3455 . We sequenced the three DNA segments of the elastase gene from non-elastase-producing strains and compared the sequences with those from the elastase-producing P . aeruginosa strains IFO 3455 and PAO1 . In P . aeruginosa N-10 and PA103, the sequences were almost identical to those from elastase-producing strains, except for several nucleotide differences . These minor differences may reflect a microheterogeneity of the elastase gene . These results suggest that two of the non-elastase-producing strains have the normal elastase structural gene and that elastase production is repressed by regulation of this gene expression in P . aeruginosa . Possible reasons for the lack of expression in these two strains are offered in this paper . In P . aeruginosa IFO 3080, the sequence had a 1-base deletion in the coding region, which should have caused a frameshift variation in the amino acid sequence . At present, we have no explanation for the abnormal posttransciptional behavior of this strain.

J Bacteriol, 1991 Oct, 173(19), 6088 - 94
Effect of regB on expression from the P1 and P2 promoters of the Pseudomonas aeruginosa regAB operon; Storey DG et al.; Exotoxin A production in Pseudomonas aeruginosa is dependent on two regulatory genes, regA and regB, which are located in tandem on the chromosome . Expression of regA and regB is controlled by two promoters (P1 and P2) situated upstream of the regAB locus . We have studied the effect of the regA and regB gene products on transcription from the regAB promoters . Transcriptional and translational fusions, under the control of the P . aeruginosa regA promoters, were used to analyze the regulation of these promoters in a variety of genetic backgrounds . When the regA P1 promoter was supplied in trans to strains lacking expression of regB (PAO1) or lacking transcription of the regAB operon (PA103-29), little activity from the P1 promoter was detected . In contrast, activity from the P2 promoter was not affected in either PAO1 or PA103-29 . Sequence analysis of the regAB operon of PA103-29 detected two mutations . One of the mutations is predicted to result in a premature stop codon in the regA open reading frame . We complemented PA103-29 with a construction containing regA and an inactive regB or a construction containing both regA and regB to directly analyze the effect of regB on transcription of the regAB operon . When PA103-29 was complemented with regA but not regB, we could not detect any transcription from the P1 promoter . Complementation of PA103-29 with both regA and regB resulted in a high level of transcription from the P1 promoter and a corresponding early transcriptional activation of toxA . Our results indicated that induction of transcription from the P1 promoter requires the regB open reading frame and thus the regAB operon is autogenously regulated in P . aeruginosa.

Crit Care Med, 1991 Oct, 19(10), 1285 - 93
Effects of hemorrhage and resuscitation on bacterial antigen-specific pulmonary plasma cell function; Robinson A et al.; BACKGROUND AND METHODS: Nosocomial pneumonia is frequent after hemorrhage and trauma, and often contributes to multiple organ system failure, morbidity, and mortality in this setting . Although the percentages and numbers of resting pulmonary B cells (clonal precursors) able to be stimulated to produce antibodies to bacterial antigens are markedly decreased after hemorrhage, the effects of hemorrhage on the pulmonary plasma cells actually producing antibody to bacterial antigens have not been examined . To investigate this question, mice were bled 30% blood volume, then resuscitated with the shed blood 1 hr later . At predetermined times after hemorrhage, the mice were intranasally immunized with liposomes containing the bacterial polysaccharide antigen levan (from Aerobacter levanicum) . One week later, lung lavages were performed to measure bacterial antigen-specific secretory immunoglobulin A (sIgA) titers and the numbers of intraparenchymal pulmonary plasma cells producing antibody against the bacterial antigen were determined . RESULTS: Reduced numbers of pulmonary plasma cells producing antibody against the immunizing bacterial polysaccharide antigen were found between 1 and 14 days after blood loss, and titers of bacterial antigen-specific secretory IgA were decreased for greater than 2 wks after hemorrhage . The importance of these abnormalities in pulmonary B-cell function was demonstrated by an increased susceptibility to Pseudomonas aeruginosa pneumonia in mice infected 4 days after hemorrhage, when bacterial antigen-specific pulmonary plasma cell numbers were at their lowest point . Resuscitated mice showed the same increased susceptibility to P . aeruginosa pneumonia as did hemorrhaged but unresuscitated animals . CONCLUSIONS: Hemorrhage, even if resuscitated, results in alterations in bacterial antigen-specific pulmonary B-cell function and secretory IgA production that are profound, long lasting, and associated with increased susceptibility to infection at this mucosal surface . Because these effects on pulmonary B-cell function do not occur immediately after hemorrhage, immunization techniques able to enhance bacterial antigen-specific secretory IgA titers at pulmonary surfaces may be able to increase resistance to nosocomial pneumonia if administered shortly after injury and blood loss.

J Infect Dis, 1991 Oct, 164(4), 803 - 6
Safety, pharmacokinetics, and functional activity of human anti-Pseudomonas aeruginosa monoclonal antibodies in septic and nonseptic patients; Saravolatz LD et al.; A mixture of five IgM human monoclonal antibodies (MAbs) against lipopolysaccharide antigens of Pseudomonas aeruginosa, plus a human IgG1 MAb against exotoxin A, were studied in 12 noninfected patients and 8 patients with P . aeruginosa bacteremia or pneumonia (or both) . The preparation was well tolerated over a dose range of 0.3-1.2 ml/kg (0.75-3.0 mg/kg IgM protein) . After a single infusion of 1.2 ml/kg (3.0 mg/kg IgM protein), serum antibody titers were boosted into therapeutic range, with serum half-lives ranging from 34 to 99 h . Also, opsonophagocytic activity in serum rose more than 1 log10 for all but one antibody . In no patient was an immunologic response against the MAb preparation detected.

Infect Immun, 1991 Oct, 59(10), 3680 - 4
Pyochelin-mediated iron transport in Pseudomonas aeruginosa: involvement of a high-molecular-mass outer membrane protein; Heinrichs DE et al.; An iron-regulated outer membrane protein of 75,000 daltons was strongly expressed following iron limitation of strains of Pseudomonas aeruginosa which fail to produce pyoverdine . A mutant nonderepressible for this protein (K372) was deficient in pyochelin-mediated iron transport at 150 nM FeCl3, consistent with a role for the 75-kDa protein in ferripyochelin transport . Moreover, ferripyochelin specifically protected the 75-kDa protein against trypsin digestion, supporting an interaction between ferripyochelin and the 75-kDa protein . Previous reports implicated a 14,000-dalton outer membrane protein as the receptor for ferripyochelin (P.A . Sokol and D.E . Woods, Infect . Immun . 40:665-669, 1983) and demonstrated that a mutant (FBP-28) expressing a defective 14-kDa outer membrane protein did not exhibit pyochelin-mediated iron transport (P.A . Sokol, J . Bacteriol . 169:3365-3368, 1987) . Nonetheless, we were able to demonstrate (i) that FBP-28 was inducible for the 75-kDa protein under iron-limiting conditions and (ii) that concomitant with the induction of this protein in FBP-28, pyochelin-mediated iron uptake at 150 nM FeCl3 was observed . Interestingly, strain K372 did transport ferripyochelin at higher (750 nM) FeCl3 concentrations, suggesting that a second pyochelin-mediated iron transport system, perhaps involving the 14-kDa outer membrane protein identified previously, operates in P . aeruginosa.

Infect Immun, 1991 Oct, 59(10), 3596 - 603
Physical mapping of virulence-associated genes in Pseudomonas aeruginosa by transverse alternating-field electrophoresis; Shortridge VD et al.; The relative chromosomal locations of 20 virulence-associated genes in four clinical isolates of Pseudomonas aeruginosa were investigated by using transverse alternating-field electrophoresis . Each strain had a characteristic restriction pattern when digested with either SpeI or DraI and electrophoresed with 15-s pulses . All four strains had restriction fragments that hybridized with each of the gene probes used, although there were variations in fragment size . An SpeI physical map constructed by Ratnaningsih et al . (E . Ratnaningsih, S . Dharmsthiti, V . Krishnapillai, A . Morgan, M . Sinclair, and B . W . Holloway, J . Gen . Microbiol . 136:2351-2357, 1990) for one of these strains, PAO1, was used to identify the location of 11 previously unmapped genes . The physical locations of the remaining genes were found to be consistent with their genetically mapped loci . Whereas phospholipase C and alginate structural and regulatory genes were associated in three separate clusters in the early, middle, and late regions of the chromosome, no virulence cluster was identified . Our data suggest that the pathogenicity of P . aeruginosa results from the gradual acquisition of genes encoding various virulence determinants.

Infect Immun, 1991 Oct, 59(10), 3492 - 7
Interaction of a salivary mucin-secretory immunoglobulin A complex with mucosal pathogens; Biesbrock AR et al.; This study examined the interaction of a human salivary low-molecular-weight mucin (MG2) with Staphylococcus aureus and Pseudomonas aeruginosa by using both solution-phase and solid-phase assays . In solution phase, MG2 in human submandibular-sublingual saliva (HSMSL) bound to the bacterial surface; however, the highly purified mucin isoforms (MG2a and MG2b) did not . Mucin binding appeared to be dependent on heterotypic complexing between MG2 and secretory immunoglobulin A (IgA), although other salivary molecules may also be involved . In contrast, in a solid-phase assay in which HSMSL, MG2-containing fractions with secretory IgA, and purified MG2 were immobilized onto a solid surface, there was minimal adherence of S . aureus . The collective results suggest that mucin binding to S . aureus and P . aeruginosa may be predicated on the formation of an MG2-secretory IgA complex . Such interactions may facilitate microbial clearance from the oral cavity and play an important role in preventing colonization of the oral cavity and the respiratory tract by potential pathogens.

Kansenshogaku Zasshi, 1991 Oct, 65(10), 1337 - 43
{Effect of macrolide antibiotics on human serum-bactericidal sensitivity of Pseudomonas aeruginosa S-6}; Tateda K et al.; It is well known that long-term administration of erythromycin (EM) at a small dose is effective for persistent infections with Pseudomonas aeruginosa in diffuse panbronchiolitis or chronic bronchitis patients . Since EM is less active against P . aeruginosa in vitro, we have been interested in the mechanisms of clinical efficacy of EM in these patients . This study examines the effect of macrolide antibiotics on human serum-bactericidal sensitivity of P . aeruginosa S-6, clinically isolated from the patient with respiratory tract infection . A significant increase in serum-bactericidal sensitivity of P . aeruginosa S-6 was observed on agar containing EM of 10 micrograms/ml after incubation for 36-60 hours (p less than 0.05) . The enhancement of serum sensitivity of P . aeruginosa S-6 was apparently observed even at a concentration of EM 1.5 micrograms/ml after the 48 hours incubation (p less than 0.01) . Of other macrolide antibiotics used, clarithromycin (CAM) also increased the serum-bactericidal sensitivity of P . aeruginosa S-6 as well as EM, however no change in the sensitivity was found with kitasamycin, josamycin, rokitamycin and oleandomycin . The results suggest that the change of serum-bactericidal sensitivity of P . aeruginosa induced by EM or CAM may, in part, contribute to the clinical efficacy of these antibiotics against persistent pulmonary P . aeruginosa infections.

Mol Microbiol, 1991 Oct, 5(10), 2315 - 21
Pseudomonas aeruginosa elastase and elastolysis revisited: recent developments; Galloway DR; With the determination of the three-dimensional structure of elastase and the probable identification of the active site and key residues involved in proteolytic activity, our knowledge of the molecular details of this interesting protease is rapidly increasing . Pseudomonas elastase appears to be remarkably similar to the Bacillus metalloproteinase thermolysin . A further significant development has been the discovery of the lasA gene and the fact that Pseudomonas elastase and alkaline proteinase appear to act in concert with the LasA protein to display the notable elastolytic activity exhibited by isolates of this organism . Biochemical and genetic studies indicate that LasA is a second elastase which may be an important virulence factor that has been overlooked in previous studies.

Nippon Seikeigeka Gakkai Zasshi, 1991 Oct, 65(10), 909 - 17
{Study on serum-sensitivity of Pseudomonas aeruginosa}; Shirahige A; Using a microtiter plate for cell culture one hundred strains of Pseudomonas aeruginosa isolated from various clinical materials were quantitatively investigated for sensitivity to the bactericidal activity of normal human serum . The sensitivity to the serum was widely distributed among these strains . In parallel, 100 strains of Pseudomonas aeruginosa were serotyped using a type-specific anti-Pseudomonas antiserum kit . All type M strains were proven to be serum-sensitive, while types G, B, and A were generally serum-resistant . Using an experimental model of osteomyelitis in mice, osteomyelitis could not be caused by serum-sensitive strains of Pseudomonas aeruginosa . These results would indicate that serum-resistance is an important factor in pathogenicity of Pseudomonas aeruginosa.

Vaccine, 1991 Oct, 9(10), 757 - 64
Oral immunization with bacterial polysaccharide and adjuvant enhances antigen-specific pulmonary secretory antibody response and resistance to pneumonia; Abraham E et al.; Nosocomial pneumonia, often due to Pseudomonas aeruginosa, occurs frequently after haemorrhage and trauma, and contributes to the increased incidence of morbidity and mortality in this clinical setting . In order to determine if enhancement of bacterial antigen-specific secretory IgA (sIgA) titres in the lungs can increase resistance to P . aeruginosa pneumonia following haemorrhage, we investigated oral immunization strategies, using bacterial polysaccharides (levan, from Aerobacter levanicum, and P . aeruginosa polysaccharide type I) and adjuvant (cholera toxin and the B-subunit of cholera toxin), capable of increasing bacterial polysaccharide-specific pulmonary secretory antibody titres . Oral co-administration of 1000 micrograms levan and 10 micrograms cholera toxin resulted in increased titres of levan-specific sIgA in lung lavages and increased numbers of levan-specific pulmonary plasma cells, but no changes in serum anti-levan titres . Similarly, oral co-administration of 1000 micrograms P . aeruginosa polysaccharide and 10 micrograms cholera toxin produced increased anti-P . aeruginosa polysaccharide titres in lung lavages . Significant decreases in anti-levan pulmonary sIgA titres and in numbers of levan-specific pulmonary plasma cells were found when oral immunization with levan and cholera toxin was performed 4 days following haemorrhage, but not if the mice were immunized 8 h after blood loss . Although haemorrhage markedly increased the susceptibility of mice to P . aeruginosa pneumonia, significant protection from mortality could be achieved through oral immunization with 1000 micrograms P . aeruginosa polysaccharide and 10 micrograms cholera toxin 8 h after haemorrhage . These results demonstrate that haemorrhage induces marked alterations in bacterial antigen-specific pulmonary B-cell responses, which contribute to the increased susceptibility to infection in this setting.(ABSTRACT TRUNCATED AT 250 WORDS)

Pneumologie, 1991 Oct, 45(10), 790 - 3
{Aspects of mucociliary clearance in mucoviscidosis}; Morr A et al.; Very often the respiratory tract of patients suffering from mucoviscidosis is infested with Pseudomonas aeruginosa which is accused of forming substances that inhibit ciliary motility . It is the aim of the present study to examine the influence of an acute and clinically relevant pseudomonas infestation on the ciliary beat frequency . The ciliary beat rate was determined in 25 mucoviscidosis patients, 13 of them were hospitalised because of acute bronchopulmonary infections . 12 of the patients did not show any clinical signs of an acute respiratory tract infection . In the group of the 13 hospitalised patients, 10 patients (77%) showed infestation of the respiratory tract with Pseudomonas aeruginosa, the mean ciliary beat frequency being markedly reduced at 8.2 +/- 1.7 Hz compared to that of a healthy group with 9.9 +/- 1.0 Hz . The 12 outpatients without clinical signs of acute respiratory tract infections did not show any reduction of the ciliary beat frequency (9.9 +/- 1.4 Hz) . Basing on these results, determination of the ciliary beat frequency may possibly develop into an auxiliary criterion to decide on starting a Pseudomonas-active antibiotic therapy.

Am Rev Respir Dis, 1991 Oct, 144(4), 959 - 61
Comparison of acridine orange stain with culture and gram stain of needle aspirate in experimental Pseudomonas pneumonia; Campbell GD et al.; The sensitivity and specificity of culture, acridine orange stain, and Gram stain were determined using needle aspiration (NA) material obtained from 82 rats with acute Pseudomonas aeruginosa pneumonia and 18 control rats . Lungs were then processed for either bacterial quantitation or histopathologic examination . NA culture proved to be the most sensitive and specific (55 and 100%, respectively) . Sensitivity of acridine orange stain was 40%, whereas Gram stain was only 29% . The specificity of each stain was at least 94% . Lung bacterial concentrations influenced the sensitivities of all three techniques, with better sensitivity found in NA samples obtained from lung with bacterial concentration of at least 10(4) colony-forming units (cfu) of P . aeruginosa . Acridine orange and Gram stain results were similar except in NA samples from lung with bacterial concentration of less than 10(4) cfu in which acridine orange stain was more sensitive . The presence of stains identifying bacteria collected from animals with sterile NA culture was found in a small but significant number of samples, suggesting the presence of nonviable though stainable organisms . Use of all three techniques (culture, acridine orange stain, and Gram stain) increased sensitivity to approximately 70% with minimal decrease of specificity.

J Hosp Infect, 1991 Oct, 19(2), 137 - 40
Strain differentiation of nosocomial isolates of Pseudomonas aeruginosa by pyrolysis mass spectrometry; Sisson PR et al.; Pyrolysis mass spectrometry (PyMS) was used for rapid interstrain comparison of Pseudomonas aeruginosa isolates from a small outbreak of sternal wound infections in a cardiothoracic surgical ward . The PyMS results were compared with those obtained by conventional O-serotyping . All the isolates were phage non-typable . Evidence obtained from PyMS of identity/non-identity between isolates correlated completely with that obtained by O-typing and correctly identified those isolates comprising the epidemic strain, in one instance in advance of O-serotyping . The speed and versatility of PyMS make it an attractive technique for the initial screening of isolates from nosocomial outbreaks of infection with P . aeruginosa and other organisms.

Antimicrob Agents Chemother, 1991 Oct, 35(10), 2091 - 7
Role of protein D2 and lipopolysaccharide in diffusion of quinolones through the outer membrane of Pseudomonas aeruginosa; Michea-Hamzehpour M et al.; Routes of quinolone permeation in Pseudomonas aeruginosa were investigated by using sparfloxacin as a prototype compound . {14C}sparfloxacin cell labeling was 13 to 28% lower in three protein D2-deficient mutants resistant to imipenem than in their imipenem-susceptible counterparts . In four impermeability-type quinolone-resistant strains isolated from pefloxacin-treated animals, we observed two- to fourfold-greater resistance to imipenem, reduced protein D2 expression in the outer membrane according to Western blotting (immunoblotting), and 25 to 29% decreased cell labeling with imipenem . In a protein D2-producing strain but not in its protein D2-deficient isogenic mutant, uptake of {14C}sparfloxacin was strongly inhibited by L-lysine and imipenem, which act as substrates for protein D2 . Conversely, binding of {14C}imipenem in a porin D2-positive strain was reduced by sparfloxacin but not by the nonamphoteric quinolone nalidixic acid . Sparfloxacin, imipenem, and lysine possess a carboxyl group and a potentially protonated nitrogen separated from each other by 0.64 to 1.07 nm as calculated by computer . Hence, protein D2 may catalyze facilitated diffusion for sparfloxacin, as it does for imipenem . In addition, pefloxacin-selected isolates contained 41 to 113% more 3-deoxy-D-mannooctulosonic acid than their quinolone-susceptible counterparts, with MIC increases of 2- to 4-fold for WIN-57273 (n-octanol-phosphate buffer partition coefficient, 13.139), 4- to 8-fold for difloxacin (partition coefficient, 3.093) and sparfloxacin (partition coefficient, 0.431), and 8- to 16-fold for norfloxacin (partition coefficient, 0.059) and ciprofloxacin (partition coefficient, 0.056) . Thus, we hypothetize that in quinolone-selected strains, increased amounts of lipopolysaccharide form a permeability barrier that acts preferentially against hydrophilic quinolones.

J Clin Invest, 1991 Oct, 88(4), 1092 - 102
Pseudomonas and neutrophil products modify transferrin and lactoferrin to create conditions that favor hydroxyl radical formation; Britigan BE et al.; In vivo most extracellular iron is bound to transferrin or lactoferrin in such a way as to be unable to catalyze the formation of hydroxyl radical from superoxide (.O2-) and hydrogen peroxide (H2O2) . At sites of Pseudomonas aeruginosa infection bacterial and neutrophil products could possibly modify transferrin and/or lactoferrin forming catalytic iron complexes . To examine this possibility, diferrictransferrin and diferriclactoferrin which had been incubated with pseudomonas elastase, pseudomonas alkaline protease, human neutrophil elastase, trypsin, or the myeloperoxidase product HOCl were added to a hypoxanthine/xanthine oxidase .O2-/H2O2 generating system . Hydroxyl radical formation was only detected with pseudomonas elastase treated diferrictransferrin and, to a much lesser extent, diferriclactoferrin . This effect was enhanced by the combination of pseudomonas elastase with other proteases, most prominently neutrophil elastase . Addition of pseudomonas elastase-treated diferrictransferrin to stimulated neutrophils also resulted in hydroxyl radical generation . Incubation of pseudomonas elastase with transferrin which had been selectively iron loaded at either the NH2- or COOH-terminal binding site yielded iron chelates with similar efficacy for hydroxyl radical catalysis . Pseudomonas elastase and HOCl treatment also decreased the ability of apotransferrin to inhibit hydroxyl radical formation by a Fe-NTA supplemented hypoxanthine/xanthine oxidase system . However, apotransferrin could be protected from the effects of HOCl if bicarbonate anion was present during the incubation . Apolactoferrin inhibition of hydroxyl radical generation was unaffected by any of the four proteases or HOCl . Alteration of transferrin by enzymes and oxidants present at sites of pseudomonas and other bacterial infections may increase the potential for local hydroxyl radical generation thereby contributing to tissue injury.

Appl Microbiol Biotechnol, 1991 Oct, 36(1), 65 - 9
Use of high density cultures of Escherichia coli for high level production of recombinant Pseudomonas aeruginosa exotoxin A; Fass R et al.; An efficient fermentation method for the production of two modified recombinant Pseudomonas aeruginosa exotoxin As cloned in Escherichia coli BL21(lambda DE3) was developed . Cell densities of 16-30 g dry weight/1 were found to be most suitable for the induction of protein synthesis, which was under the isopropyl beta-D-thiogalactopyranoside (IPTG)-inducible T7 expression system . A concentration of 0.6 mM IPTG and induction time of 90 min were found to give the best results for production of the modified toxins . Using this procedure, gram amounts of the proteins were obtained in a 3-1 bench-top fermentor . The high density growth of the bacteria did not impair the integrity of the proteins and did not interfere with the purification procedure.

Lancet, 1991 Sep 21, 338(8769), 725 - 6
Prevention of chronic Pseudomonas aeruginosa colonisation in cystic fibrosis by early treatment; Valerius NH et al.; To assess whether chronic pulmonary colonisation with Pseudomonas aeruginosa in cystic fibrosis is preventable, 26 patients who had never received anti-pseudomonas chemotherapy were randomly allocated to groups receiving either no anti-pseudomonas chemotherapy or oral ciprofloxacin and aerosol inhalations of colistin twice daily for 3 weeks, whenever Ps aeruginosa was isolated from routine sputum cultures . During the 27 months of the trial, infection with Ps aeruginosa became chronic in significantly fewer treated than untreated subjects (2 {14%} vs 7 {58%}; p less than 0.05) and there were significantly fewer Ps aeruginosa isolates in routine sputum cultures in the treated group (49/214 {23%} vs 64/158 {41%}; p = 0.0006) . Thus, chronic colonisation with Ps aeruginosa can be prevented in cystic fibrosis by early institution of anti-pseudomonas chemotherapy.

J Immunol Methods, 1991 Sep 20, 143(1), 69 - 72
C-reactive protein measured in dried blood spots from patients with cystic fibrosis; Cordon SM et al.; There was no significant difference in C-reactive protein concentration determined in paired serum and eluates from dried blood spots collected on Guthrie cards; mean difference 0.6 microgram/ml (95% CI -3.3-2.2 micrograms/ml; n = 101) . Dried blood spot samples were stable for up to 21 days and were unaffected by posting to the laboratory . In eight patients with cystic fibrosis undergoing specific antibiotic treatment for Pseudomonas aeruginosa pulmonary infection the fall in C-reactive protein concentration was not significantly different between serum and dried whole blood spot specimens . This method could be used to monitor infection and the response to antibiotic treatment.

Biochemistry, 1991 Sep 17, 30(37), 9040 - 6
Solution structure of Fe(II) cytochrome c551 from Pseudomonas aeruginosa as determined by two-dimensional 1H NMR; Detlefsen DJ et al.; The solution structure of Fe(II) cytochrome c551 from Pseudomonas aeruginosa based on 2D 1H NMR data is reported . Two sets of structure calculations were completed with a combination of simulated annealing and distance geometry calculations: one set of 20 structures included the heme-peptide covalent linkages, and one set of 10 structures excluded them . The main-chain atoms were well constrained within the two structural ensembles (1.30 and 1.35 A average RMSD, respectively) except for two regions spanning residues 30-40 and 60-70 . The results were essentially the same when global fold comparisons were made between the ensembles with an average RMSD of 1.33 A . In total, 556 constraints were used, including 479 NOEs, 53 volume constraints, and 24 other distances . This report represents the first solution structure determination of a heme protein by 2D 1H NMR and should provide a basis for the application of these techniques to other proteins containing large prosthetic groups or cofactors.

J Biol Chem, 1991 Sep 15, 266(26), 17376 - 81
Increased cytotoxic activity of Pseudomonas exotoxin and two chimeric toxins ending in KDEL; Seetharam S et al.; Pseudomonas exotoxin (PE) is a 66,000 molecular weight protein secreted by Pseudomonas aeruginosa . PE is made up of three domains, and PE40 is a form of PE which lacks domain Ia (amino acids 1-252) and has very low cytotoxicity because it cannot bind to target cells . The sequence Arg-Glu-Asp-Leu-Lys (REDLK) at the carboxyl terminus of Pseudomonas exotoxin has been shown to be important for its cytotoxic activity (Chaudhary, V . K., Jinno, Y., FitzGerald, D . J., and Pastan, I . (1990) Proc . Natl . Acad . Sci . U.S.A . 87, 308-312) . In this study, we tested the effect of altering the carboxyl sequence of PE from REDLK to the characteristic endoplasmic reticulum retention sequence, KDEL, or to KDEL repeated three times (KDEL)3 . We also made similar changes at the carboxyl terminus of two chimeric toxins in which domain I of PE (amino acids 1-252) was either replaced with transforming growth factor alpha (TGF alpha) to make TGF alpha-PE40 or with a single chain antibody (anti-Tac) reacting with the human interleukin 2 receptor to make anti-Tac(Fv)-PE40 . Statistical analyses of our results demonstrate that PE and its derivatives ending in KDEL or (KDEL)3 are significantly more active than PE or derivatives ending in REDLK . We have also found that brefeldin A, which is known to perturb the endoplasmic reticulum, inhibits the cytotoxic action of PE . Our results suggest that the altered carboxyl terminus may enable the toxin to interact more efficiently with a cellular component involved in translocation of the toxin to the cytosol.

J Immunol, 1991 Sep 15, 147(6), 1869 - 76
Complement deposition by antibodies to Pseudomonas aeruginosa mucoid exopolysaccharide (MEP) and by non-MEP specific opsonins; Pier GB et al.; The failure of cystic fibrosis patients to limit chronic infection due to mucoid Pseudomonas aeruginosa might be due to ineffective opsonins produced against this bacterium . Nonopsonizing antibody to the bacterial capsule, mucoid exopolysaccharide (MEP), appears at elevated titers during chronic colonization of cystic fibrosis patients, as do opsonins not specific for MEP . Nonopsonic antibodies to MEP occur naturally in most adults and can be induced in animals by immunization . A limited number of humans produce MEP-specific opsonic antibodies after immunization . The purpose of this study was to compare the activation and deposition of C components onto the bacterial surface in the presence of these different antibodies . Opsonic killing uses the classical C pathway . MEP-specific opsonic and nonopsonic antibodies bound to whole bacteria and activated C to a comparable degree, but opsonic antibody deposited 3 to 40 times more C3 onto bacteria, mostly as C3bi, compared to nonopsonic antibody . In addition, two to three times as much nonopsonic mAb as opsonic mAb (both IgG2b) bound to the bacteria at comparable input concentrations, indicating the difference in C deposition was not due to differences in antibody binding . Non-MEP-specific opsonins also bound C3 to the bacteria, but only a mean of 27 +/- 14% was ester linked, compared with 81 +/- 11% of C3 deposited by MEP-specific opsonins . Immunoprecipitation experiments indicated that two-thirds of the C3 bound in the presence of MEP-specific opsonins was linked to MEP, whereas non-MEP-specific opsonins obtained from infected patients deposited the C3 onto LPS and other unidentified Ag . These data show that MEP-specific opsonins function by depositing C3 onto the outer bacterial surface that differentiates them from non-MEP-specific opsonins produced in response to chronic infection.

Biochem J, 1991 Sep 15, 278 ( Pt 3), 817 - 20
Electron transfer between horse ferritin and ferrihaemoproteins; Kadir FH et al.; Reactions of reduced horse spleen ferritin with horse and Saccharomyces cerevisiae ferricytochromes c, cow ferricytochrome b5, sperm-whale metmyoglobin and Pseudomonas aeruginosa ferricytochrome c-551 were investigated by u.v.-visible spectrophotometry . In all cases the reduced ferritin reduced the ferrihaemoproteins . The rate of reduction varied from less than 0.2 M-1.s-1 for metmyoglobin to 1.1 x 10(3) M-1.s-1 for horse ferricytochrome c (0.1 M-phosphate buffer, pH 7.4, at 25 degrees C) . We conclude that the mechanism of ferrihaemoprotein reduction involves long-range electron transfer through the coat of ferritin and that such electron transfer is rapid enough to account for the rates of iron release observed by other workers in reductive release assays.

Antimicrob Agents Chemother, 1991 Sep, 35(9), 1905 - 10
Integration of pharmacokinetics and pharmacodynamics of imipenem in a human-adapted mouse model; Fluckiger U et al.; The relationship between the pharmacokinetics and bactericidal activity of imipenem against Pseudomonas aeruginosa and Escherichia coli was investigated in a neutropenic mouse thigh infection model . To circumvent the problem of short elimination time in small animals, imipenem was administered in fractionized, decreasing doses such that the pharmacokinetic profiles as observed in humans after intravenous and intramuscular injections were approximated in mice . The human-simulated kinetic profile corresponding to an intramuscular injection of 500 mg at 12-h intervals proved to be as effective as the human-simulated profile of the same dose injected intravenously every 6 h . In contrast, the human-simulated profile corresponding to only one intravenous injection every 12 h resulted in bacterial breakthrough growth between 8 and 12 h after the onset of treatment . The results of our investigations confirm the hypothesis that the bactericidal effect of imipenem against P . aeruginosa and E . coli in vivo depends mainly on the time during which drug levels remain above the MIC rather than on the plasma peak/MIC ratio.

Ann Plast Surg, 1991 Sep, 27(3), 265 - 8
Antiseptic effectiveness with fibroblast preservation; McKenna PJ et al.; The efficacy of topical antiseptic therapy for wounds and skin ulcers has been shown to be at the expense of fibroblast and leukocyte function and, in general, wound healing . Specifically, continued fibroblast function after exposure to antiseptics has been correlated to the concentration of the antiseptic . At concentrations that preserve fibroblast function, 0.005% sodium hypochlorite, 0.001% providone-iodine, 0.0025% acetic acid, and 0.003% hydrogen peroxide were tested for their effectiveness against various clinical isolates . Staphylococcus aureus, Escherichia coli, Group D enterococci, Pseudomonas aeruginosa, and Bacteroides fragilis were exposed to the antiseptics and plated in a standard microbiological fashion . The cultures showed that sodium hypochlorite inhibited the growth of all the bacteria (p less than 0.001), whereas povidone-iodine reduced the colonies of S . aureus and acetic acid inhibited P . aeruginosa . Our study suggests that 0.005% sodium hypochlorite can be used as a debriding and topical antibacterial agent for wounds and skin ulcers without inhibiting fibroblast activity essential to normal wound repair.

Thorax, 1991 Sep, 46(9), 683 - 4
Pancoast's syndrome due to Pseudomonas aeruginosa infection of the lung apex; Vandenplas O et al.; A case of Pancoast's syndrome was caused by Pseudomonas aeruginosa infection of the lung apex . The infection extended to extrapleural structures of the thoracic inlet.

J Antibiot (Tokyo), 1991 Sep, 44(9), 985 - 94
Acclimatization resistance of a Pseudomonas aeruginosa prototype strain to imipenem; Kapotas NM; A prototype sensitive strain of Pseudomonas aeruginosa (IRs) was acclimatized in vitro to imipenem by serial transfers in broth containing increasing concentrations of the antibiotic up to 32 micrograms/ml . Serial subculture of the resistant progeny (IR1r) in antibiotic-free solid media resulted in a "revertant" progeny (IR2r) that retained resistance to imipenem . Acclimatization resistance to imipenem and the attempted reversion procedure affected colony morphology, growth rate, pigment production, growth at 42 degrees C and glucose oxidation . SDS-PAGE analysis of the outer membrane proteins revealed in strain IR1r a complete loss of 6 proteins that were present in IRs (85 kdaltons, 46 kdaltons or porin D1, 45.5 kdaltons or porin D2, 43 kdaltons or porin E, 21 kdaltons or protein H1 and 20.5 kdaltons or lipoprotein H2) and in strain IR2r a complete loss of 3 proteins (46 kdaltons, 43 kdaltons, 20.5 kdaltons), while three others were found only in trace amounts (75 kdaltons, 45.5 kdaltons and 21 kdaltons) . In the outer membranes of strains IR1r and IR2r an acquisition of a 56-kdalton protein was noted . Lipopolysaccharide chemical analysis revealed a marked, partially reversible increase in 2-keto-3-deoxyoctonate, total hexose and heptose constituents; readily extractable lipid chemical analysis and TLC, revealed a marked, partially reversible, increase in the phospholipid content of the outer membrane . Acclimatization resistance to imipenem was accompanied by cross-resistance to gentamicin, by partially reversible cross-resistance to moxalactam, carbenicillin and ticarcillin and by fully reversible cross-resistance to aztreonam . Sensitivity to azlocillin and polymyxin B remained unaltered . To explain this type of resistance to imipenem, an irreversible, non-inducible "loss" mutation mechanism, working in concert with a partially reversible mechanism, is proposed.

Cornea, 1991 Sep, 10(5), 387 - 9
The effects of fibronectin on the adherence of bacteria to corneal epithelium; Matoba AY et al.; The aim of our experiments was to determine whether treatment with topical fibronectin led to increased adherence of Staphylococcus aureus or Pseudomonas aeruginosa to rabbit corneas with epithelial defects . No significant effect of fibronectin was demonstrated . For all strains of S . aureus tested, the number of recoverable organisms was decreased at 24 h compared to 1 h . None of the rabbits developed infectious keratitis.

Clin Chest Med, 1991 Sep, 12(3), 523 - 43
The impact of tracheal intubation on host defenses and risks for nosocomial pneumonia; Levine SA et al.; Nosocomial pneumonia remains a common complication in patients treated with endotracheal intubation and mechanical ventilation and continues to have a significant impact on the mortality rate of these patients . Epidemiologic studies have shown that the risk of pneumonia increases with the duration of intubation but that the period of highest risk is the first 2 weeks of therapy . Gram-negative bacteria account for most nosocomial pneumonias in intubated patients, but Staphylococcus aureus may also play a role in what may be a polymicrobial infection . In the most seriously ill individuals, and in those treated with long-term mechanical ventilation, Pseudomonas aeruginosa is a common pathogen . Endotracheal intubation and mechanical ventilation predispose to pneumonia for a variety of reasons (see Fig . 1) . The endotracheal tube can have direct effects on the airway that result in a reduction in local host defenses . Thus, mucosal injury can reduce mucociliary function, while upper airway defenses are bypassed and the effectiveness of cough is reduced . Indirectly, intubation can result in an enhanced capacity of tracheobronchial cells to bind gram-negative bacteria, an effect that favors airway colonization and pneumonia . The injury to the airway can create binding sites for bacteria in the basement membrane of the bronchial tree and the stimulation of the secretion of mucus, which then stagnates and can create potential sites for bacterial adherence . The endotracheal tube also enhances bacterial entry to the lung by serving as a reservoir for bacteria to remain sequestered, safe from host defenses . Respiratory therapy devices can allow bacteria to proliferate and can then introduce them into the patient if not handled properly . Finally, patients who are ill enough to require intubation also have disease-associated impairments in systemic host defense, which add to the impairments caused by the use of an artificial airway . The host defense impairments that occur in mechanically ventilated patients can lead to respiratory tract infection in the form of either febrile tracheobronchitis or pneumonia . The diagnosis of pneumonia in intubated patients is difficult and controversial . It can be made by either clinical criteria or microbiologic criteria, the latter by using a bronchoscopically directed protected specimen brush . Therapy of pneumonia in mechanically ventilated patients is not always successful, and systemic antibiotics may need to be supplemented by topical antimicrobials . No clearly effective prophylactic strategy currently exists, but our understanding of pneumonia pathogenesis has led to some promising directions . As more data are collected, inhaled antibiotics, selective digestive decontamination, and enhancement of host defenses by cytokines and pre-formed antibodies may emerge as useful approaches.

Arch Dis Child, 1991 Sep, 66(9), 1022 - 6; discussion 1016-7
Heart-lung transplantation for cystic fibrosis . 2: Outcome; Whitehead B et al.; From March 1988 to March 1990, 11 children with cystic fibrosis (age 5-15 years) underwent combined heart-lung transplantation at our institutes . Maintenance immunosuppression consisted of cyclosporin and azathioprine with corticosteroids and antithymocyte globulin used perioperatively and during rejection episodes . Six patients (55%) survive from 1.5-23 months all of whom have improved life quality . Actuarial survival to 1 year was 55% . At six months after transplant, mean forced expiratory volume at one second was 73.5% of predicted normal, compared with 25% before transplant . There was one perioperative death, three later deaths associated with obliterative bronchiolitis at two, eight, and nine months, and one from mediastinitis at four months . Of the 15 children accepted for transplantation but not receiving grafts, 10 have died (eight within four months of being placed onto the transplant list) . Early postoperative problems included acute reversible rejection (n = 10), meconium ileus equivalent (n = 3), and pancreatitis (n = 1) . There was a high incidence of later pulmonary rejection with a mean of 5.7 episodes per patient in the first six months . Pulmonary infection occurred relatively infrequently, with Pseudomonas aeruginosa being the most common pathogen . Persistent diabetes mellitus requiring insulin occurred in four and systemic hypertension developed in one.

Transfusion, 1991 Sep, 31(7), 620 - 6
White cells protect donor blood against bacterial contamination; Hogman CF et al.; The possible beneficial role of white cells (WBCs) in donor blood has been investigated with respect to their capacity to remove bacteria . Preparations of buffy coat and whole blood, containing as well as reduced of WBCs, were inoculated with Staphylococcus epidermidis, S . aureus, Escherichia coli, Pseudomonas aeruginosa, and Propionibacterium species . Upon storage at room temperature, the presence of WBCs resulted in a reduction of the bacterial content . Units inoculated with S . epidermidis and E . coli were completely cleared of bacteria within 5 to 24 hours . On the other hand, S . aureus, after an initial reduction in number, started to multiply . In WBC-reduced units, the initial bacterial content remained unchanged for 5 hours, but the bacteria then exhibited vigorous growth within 48 hours in buffy coat and slower growth in whole blood . Propionibacterium sp . did not grow with or without WBCs . P . aeruginosa did not grow in buffy coat but showed a growth pattern similar to that of S . aureus in whole blood . The presence of WBCs in the donor blood during the first hours after collection thus seems to rid the blood of at least some species of bacteria . These results indicate that it would be favorable not to perform WBC reduction during blood collection and that several hours of contact can be needed to obtain sterility.

J Bacteriol, 1991 Sep, 173(18), 5624 - 30
Molecular cloning of genes involved with expression of A-band lipopolysaccharide, an antigenically conserved form, in Pseudomonas aeruginosa; Lightfoot J et al.; Most strains of Pseudomonas aeruginosa can express two chemically and immunologically distinct types of lipopolysaccharide (LPS), an antigenically conserved form called A band and the serotype-specific form called B band . To study the molecular controls regulating expression of the A-band LPS antigen, we have cloned the genes involved with A-band LPS expression . Strain AK1401, a phage-resistant mutant of PAO1 which was shown previously to produce only A-band LPS and not the O-antigen-containing B-band LPS, was mutagenized by using ethyl methanesulfonate to generate an A-band-deficient mutant called rd7513 . A cosmid clone bank of P . aeruginosa PAO1 whole genomic DNA was constructed in Escherichia coli . The gene bank was mobilized en masse into strain rd7513, and detection of complementation of synthesis of A band was done by screening transconjugants in a colony immunoblot assay with the A-band-specific monoclonal antibody N1F10 . One recombinant cosmid, pFV3, complemented synthesis of A-band polysaccharide in rd7513 . Silver-stained polyacrylamide gel and Western immunoblot analyses of LPS extracted from the transconjugant rd7513(pFV3) showed that the A band produced had a higher molecular weight than the A band of AK1401 . Analysis of the plasmid pFV3 showed that it contained a chromosomal insert of 27 kb . Two subclones of pFV3, namely, pFV35 and pFV36, containing chromosomal inserts of 5.3 and 4.2 kb, respectively, also complemented A-band expression in rd7513 . The LPS banding profile of rd7513(pFV35) was similar to that of AK1401, while the LPS profile of rd7513(pFV36) more closely resembled that of rd7513(pFV3) . pFV3 complemented A-band expression in five of the six P . aeruginosa O serotypes which lack A band as well as in rough strain AK44 but failed to complement A-band expression in core mutants AK1012 and AK1282, suggesting that pFV3 contains genes for A-band expression and that synthesis of a complete core region in isogenic mutant strains is required for A-band synthesis.

J Infect Dis, 1991 Sep, 164(3), 499 - 506
Combination therapy with ciprofloxacin plus azlocillin against Pseudomonas aeruginosa: effect of simultaneous versus staggered administration in an in vitro model of infection; Dudley MN et al.; The effect of dose scheduling on the pharmacodynamics of simulated human doses of ciprofloxacin (200 mg intravenously {iv} every 12 h) and azlocillin (4 g iv every 12 h) alone or in combination against Pseudomonas aeruginosa was studied in a two-compartment in vitro kinetic model of infection . Studies with the two drugs in combination were compared using simultaneous or staggered (first doses of each drug were administered 6 h apart) dosing schedules . Bacterial regrowth and resistance were prevented by all combination dosing schedules; however, the simultaneous regimen consistently provided the greatest extent of killing for all strains, particularly in those initially resistant to ciprofloxacin . These enhanced effects of the combination were corroborated by an increase in the peak and duration of bactericidal activity in the analogous "serum" compartment of the model . These data show the potential usefulness of simultaneous dosing of an antipseudomonal beta-lactam with ciprofloxacin against P . aeruginosa.

Am Rev Respir Dis, 1991 Sep, 144(3 Pt 2), S19 - 24
The carbohydrate diversity of human respiratory mucins: a protection of the underlying mucosa?
Lamblin G, Lhermitte M, Klein A, Houdret N, Scharfman A, Ramphal R, Roussel P.
Human respiratory mucins consist of a family of glycoproteins with different peptides in which glycosylation, the major post-translational phenomenon, is responsible for about 70 to 80% of the weight of these molecules . This glycosylation generates a remarkable diversity of O-glycosidically linked carbohydrate chains, which are expressed as several hundreds of different chains in a single person . These chains, which can vary from one to about 20 sugars, may be neutral, sialylated, or sulfated . They bear multiple epitopes . Some antigenic determinants such as ABO, Leb antigens in secretor individuals, Lea, or X or Y antigens have been identified . There is increasing evidence that, among other functions, this diversity of chains allows many interactions with microorganisms and may be an important factor in maintaining the sterility of the respiratory tree . In certain pathologic situations such as cystic fibrosis, which is associated with colonization by Pseudomonas aeruginosa, the hypothesis of an alteration of this interaction is open.

J Clin Invest, 1991 Sep, 88(3), 885 - 90
Efficacy of antilipopolysaccharide and anti-tumor necrosis factor monoclonal antibodies in a neutropenic rat model of Pseudomonas sepsis; Opal SM et al.; Monoclonal antibodies (MAb) directed against bacterial lipopolysaccharide (LPS) and tumor necrosis factor-alpha (TNF) provide partial protection in experimental models of septic shock . To determine if additional benefit accrues from a combination of anti-TNF and anti-LPS MAb in the treatment of septic shock, a neutropenic rat model was developed to study active infection with Pseudomonas aeruginosa 12.4.4 . Animals were treated intravenously with an irrelevant MAb (group 1); anti-TNF MAb (group 2); MAb directed against P . aeruginosa 12.4.4 LPS (group 3); or a combination of anti-TNF and anti-LPS MAb (group 4) . None of the control animals in group 1 survived the 7-d period of neutropenia (0/16) . In contrast, the survival rate was 44% in group 2 (P less than 0.02); 37% in group 3 (P less than 0.05); and 75% in group 4 (P less than 0.0002) . The combination of monoclonal antibodies provided greater protection than either MAb given alone (P less than 0.05) . Serum TNF levels during infection were significantly greater in groups 1 and 3 (20.1 +/- 3.3 U, mean +/- SE) than in groups 2 and 4 (0.9 +/- 0.8 U, P less than 0.0001) . These results indicate that a combination of monoclonal antibodies to LPS and TNF have additive benefit in experimental Pseudomonas aeruginosa sepsis . This immunotherapeutic approach may be of potential utility in the management of serious, gram-negative bacterial infection in neutropenic patients.

Infect Immun, 1991 Sep, 59(9), 2880 - 4
Mouse liver contains a Pseudomonas aeruginosa exotoxin A-binding protein; Forristal JJ et al.; The opportunistic pathogen Pseudomonas aeruginosa produces several potential virulence factors, including the ADP-ribosylating toxin, exotoxin A (PE) . Studies using a burned mouse model have shown that PE consistently inhibits protein synthesis and depletes elongation factor 2 in mouse liver and variably in other organs . One reason for toxin sensitivity could be the presence of a PE receptor on the surface of cells . Therefore we examined detergent extracts of mouse tissues for the presence of toxin-binding proteins . Proteins which specifically bind PE were present in extracts from liver, kidney, lung, spleen, and heart . Because liver appears to be a prominent target for the toxin in a burned animal, we choose to isolate the PE-binding protein from mouse liver and compare this protein to the recently characterized toxin-binding protein from toxin-sensitive mouse LM fibroblasts . The toxin-binding proteins from both sources have a molecular mass of approximately 350 kDa, share similar protease digestion profiles, and are glycosylated . However the glycosylation patterns for the two species are quite different . Both glycoproteins bind toxin with high avidity . The toxin-binding moiety is located, at least in part, on the plasma membrane and thus could represent the receptor involved in internalization of toxin molecules responsible for cell death.

J Bacteriol, 1991 Sep, 173(17), 5290 - 7
Pseudomonas aeruginosa alkaline protease: evidence for secretion genes and study of secretion mechanism; Guzzo J et al.; A 6.5-kb DNA fragment carrying the functions required for specific secretion of the extracellular alkaline protease produced by Pseudomonas aeruginosa was cloned . The whole 6.5-kb DNA fragment was transcribed in one direction and probably carried three genes involved in secretion . The expression in trans of these genes, together with the apr gene, in Escherichia coli allowed synthesis and secretion of the alkaline protease, which was extensively investigated by performing pulse-chase experiments under various conditions . We demonstrated the absence of a precursor form, as well as the independence of alkaline protease translocation from SecA . The absence of secretion genes impaired alkaline protease secretion; the protein then remained intracellular and was partially degraded.

J Infect Dis, 1991 Sep, 164(3), 507 - 14
Induction of opsonic antibodies to Pseudomonas aeruginosa mucoid exopolysaccharide by an anti-idiotypic monoclonal antibody; Schreiber JR et al.; Mucoid strains of Pseudomonas aeruginosa are the major pulmonary pathogens for cystic fibrosis patients . Opsonizing antibodies to the mucoid exopolysaccharide (MEP) antigen may protect animals and some cystic fibrosis patients from infection . However, MEP does not readily elicit opsonic antibodies either during chronic infection or after vaccination . To evaluate alternative means to induce opsonic antibodies, a murine monoclonal anti-idiotypic antibody directed to an opsonic monoclonal antibody specific to MEP was produced . The anti-idiotypic antibody bound to F(ab')2 fragments of the opsonic antibody, blocked binding to MEP, bound to cross-reactive idiotopes on human opsonic antibodies to MEP, and elicited MEP-specific antibodies in syngeneic and allogeneic mice . These anti-idiotype-induced, MEP-specific antibodies fixed complement to mucoid P . aeruginosa cells and opsonized them for phagocytic killing by human leukocytes . These studies demonstrate the potential utility of anti-idiotypic monoclonal antibody for generating protective immunity against bacterial polysaccharides.

Eur Respir J, 1991 Sep, 4(8), 1004 - 9
Prevention of leucocyte elastase-induced emphysema in mice by heparin fragments; Lafuma C et al.; Heparin and its derivatives inhibit human leucocyte proteinases i.e . elastase and cathepsin G, but do not inhibit porcine pancreatic elastase and Pseudomonas aeruginosa elastase . In vitro experiments, reported here, also indicate that elastin, one of the physiological substrates of human leucocyte elastase (HLE), could decrease by 30-fold the inhibitory potential of an hexadecasaccharide heparin fragment (dp 16) isolated from CY 222 . Nevertheless, the inhibitory capacity of the heparin fragment still remains elevated with IC50 = 2.7 x 10(-7) M and still inhibits HLE in its free and adsorbed state to elastin . These overall data prompted us to evaluate the influence of CY 222 in HLE-induced emphysema . Emphysema was induced in mice eight weeks old, following a single instillation of 200 micrograms of HLE . CY 222 treated animals received 2.5 mg.kg-1 subcutaneously once daily, 6 days per week during 4 weeks prior to HLE instillation, and for eight weeks following HLE instillation . The heparin fragment treatment of the mice halved the mortality rate observed early following HLE instillation . After 8 weeks, surviving animals were examined for lung histological and morphometrical changes: mean linear intercept (MLI) and internal alveolar area (ISA) . The CY 222 heparin fragments exerted a protective effect against HLE-induced emphysema by decreasing by 70% the MLI; these heparin fragments exerted no effect on emphysema induced by pancreatic elastase in hamsters or mice . Heparin derivatives represent a new class of physiological HLE low molecular weight inhibitors capable of preventing HLE-induced emphysema.

Antibiot Khimioter, 1991 Sep, 36(9), 39 - 40
{Chemotherapy of Pseudomonas aeruginosa infections in children during the first three months of life}; Litiaeva LA et al.; The data on the efficacy of antibacterial drugs and their combinations in treatment of 150 three-month old infants with generalized infection due to Pseudomonas aeruginosa are presented . The clinical isolates of P . aeruginosa were found to be carriers of multiple drug resistance which markedly complicated the chemotherapy . Only combined antibacterial therapy of such infants proved to be rational . High activity of aminoglycosides, azlocillin and cefotaxime against P . aeruginosa and the synergistic action of their combinations observed in the patients permitted to recommend the use of combinations of the above drugs in the empirical chemotherapy.

Antibiot Khimioter, 1991 Sep, 36(9), 25 - 7
{Treatment of endophthalmitis with a single intravitreous administration of cefotaxime and gentamicin in an experiment}; Moroz AF et al.; Experimental endophthalmitis was treated with single intravitreous administrations of cefotaxime (claforan) and gentamicin . It was found that a single administration of cefotaxime to the vitreous body prevented development of endophthalmitis in rabbits previously infected with Staphylococcus aureus, E . coli and Pseudomonas aeruginosa . Vitrectomy in the treatment of endophthalmitis was shown to be promising and provide satisfactory anatomical and functional results.

J Inorg Biochem, 1991 Sep, 43(4), 753 - 8
Mössbauer spectroscopic studies of iron in Pseudomonas aeruginosa; Kadir FH et al.; The present Mossbauer spectroscopic studies of isolated bacterioferritin and whole cells of Pseudomonas aeruginosa have shown that the iron core of bacterioferritin is not altered on isolation . These studies have also shown that the bacterioferritin core is typically 85% oxidized within the cell and may contain a significant proportion of its iron as small clusters during the early stage of the stationary phase of cell growth.

J Biochem (Tokyo), 1991 Sep, 110(3), 345 - 9
Application of bimane-peptide substrates to spectrofluorometric assays of metalloendopeptidases; Kajiwara K et al.; A spectrofluorometric method for sensitive determination of metalloendopeptidase activity has been developed by using a bimane-peptide containing a tryptophan residue, i.e . 1,7-dioxo-2,5,6-trimethyl-1H,7H-pyrazolo{1,2-alpha}pyrazol-3-yl-methyl- thiomethylcarbonyl-phenylalanyl-tryptophanyl-leucine (Bim-SCH2CO-Phe-Trp-Leu-OH) . Such an "intramolecularly quenched" substrate was originally designed for a sensitive assay of angiotensin I converting enzyme (ACE) {Sato, E . et al . (1989) Chem . Pharm . Bull . 37, 145-147} . All the typical metalloendopeptidases tested, such as thermolysin, Pseudomonas aeruginosa (Ps.) elastase, Streptomyces griseus metalloendopeptidases I and II (SGMPI and SGMPII), and alkinonase A, a metalloendopeptidase from Streptomyces violaceorectus, cleaved this substrate strictly at a Phe-Trp bond, leading to a marked increase in fluorescence . Kinetic parameters of the enzymatic hydrolyses of five kinds of analogous bimane substrates were compared to examine how the nature of neighboring amino acid residues on either side of the cleavable bond affects the catalytic efficiency of each of the metalloendopeptidases . Bim-SCH2CO-Phe-Trp-Leu-OH was most efficiently hydrolyzed by all of these enzymes . The use of this substrate made it possible to determine minute amounts of metalloendopeptidases, especially those originating from Streptomycetes (for example, as little as 10 fmol of SGMPII).

Mol Microbiol, 1991 Sep, 5(9), 2125 - 31
Pseudomonas aeruginosa LasB mutant constructed by insertional mutagenesis reveals elastolytic activity due to alkaline proteinase and the LasA fragment; Wolz C et al.; The extracellularly secreted endopeptidase elastase (LasB) is regarded as an important virulence factor of Pseudomonas aeruginosa . It has also been implicated in the processing of LasA which enhances elastolytic activity of LasB . In order to investigate the role of LasB in virulence and LasA processing, a LasB-negative mutant, PAO1E, was constructed by insertional mutagenesis of the LasB structural gene, lasB, in P . aeruginosa PAO . An internal 636 bp lasB fragment of the plasmid pRB1803 was ligated into a derivative of the mobilization vector pSUP201-1 . The resulting plasmid, pBRMOB-LasB, was transformed into Escherichia coli and transferred by filter matings to the LasB-positive P . aeruginosa strain, PAO1 . Plasmid integration in the lasB site of the chromosome was confirmed by Southern blot analysis . Radioimmunoassay and immunoblotting of PAO1E supernatant fluids yielded no detectable LasB (less than 1 ng ml-1 LasB) . The absence of LasB in PAO1E was further proven by the inability of its culture supernatant fluid to cleave transferrin or rabbit immunoglobulin G (IgG) after a 72 h incubation . The residual proteolytic activity of PAO1E culture supernatant fluid was attributed to alkaline proteinase (Apr), since it was totally inhibited by specific antibodies against Apr . Residual elastolytic activity in culture supernatant fluid of PAO1E was due to the LasA fragment and to the combined action of the LasA fragment with Apr on elastin . The sizes of purified LasA from PAO1 and PAO1E were identical (22 kDa) . These results show that, besides LasB and the LasA fragment, Apr may also act on elastin in the presence of the LasA fragment and that the proteolytic processing of LasA in P . aeruginosa is independent of LasB.

Zh Mikrobiol Epidemiol Immunobiol, 1991 Sep, (9), 27 - 9
{Hospital strains of Pseudomonas aeruginosa in the surgical clinic}; Iskhakova KhI et al.; Circulation of different antigenic variants of P . aeruginosa in a surgical hospital was studied . In this study the process leading to the formation of pathogenic hospital strains, determined by time and location, from some serovars is demonstrated . The study also established that the department of the hospital where the selection of hospital strains mainly occurred was the resuscitation ward . Some pyoseptic infections of P . aeruginosa etiology with fetal outcome were found to be caused in most cases by hospital strains characteristic of the hospital in the period under study.

J Appl Physiol, 1991 Sep, 71(3), 915 - 23
Ibuprofen attenuates plasma tumor necrosis factor activity during sepsis-induced acute lung injury; Leeper-Woodford SK et al.; Plasma tumor necrosis factor (TNF) activity, cardiac index, extravascular lung water, systemic and pulmonary arterial pressures, pulmonary vascular resistance index, and arterial PO2 were monitored for 300 min in four groups of anesthetized pigs: saline-infused animals (n = 5), saline-infused animals given ibuprofen (12.5 mg/kg iv) at 0 and 120 min (n = 4), animals infused for 60 min with live Pseudomonas aeruginosa (Ps, 5 x 10(8) organisms/ml at 0.3 ml.20 kg-1.min-1, n = 6), and animals infused for 60 min with Ps plus ibuprofen administered at 0 and 120 min (n = 4) . Infusion of Ps induced significant elevations (greater than 4-fold increase in units/ml of TNF by 60 min, P less than 0.05) in plasma TNF activity (L929 cytolysis assay) and alterations (P less than 0.05) in all hemodynamic and pulmonary parameters within 30-60 min . Ibuprofen administration in sepsis significantly decreased peak TNF activity by 2 units/ml and attenuated many of the physiological alterations due to sepsis . These results show that ibuprofen attenuates sepsis-induced injury and that alterations of acute septic insult are correlated with reduced plasma TNF activity in septic animals given ibuprofen.

Mol Biol (Mosk), 1991 Sep-Oct, 25(5), 1188 - 96
{Cytotoxic properties of a recombinant hybrid of the A protein of Staphylococcus aureus with a fragment of exotoxin A of Pseudomonas aeruginosa}; Tonevitskii AG et al.; By gene-engineering technique a chimeric protein made up of fragments of Staphylococcus aureus protein A and .Pseudomonas aeruginosa exotoxin A has been constructed . The chimeric protein was shown to preserve features characteristic of its both constituents--it ADP-ribosylates elongation factor 2 and binds to Ig . Cytotoxic properties of the chimeric protein were studied in two model systems . Treatment of target cells in both systems was performed successively with antibodies against corresponding antigens and after washing--with recombinant chimeric toxin which bound to antibodies on the surface of target cells . In the first model system human B-lymphoma cells (Daudi line) carrying Ig molecules on their surface were treated with polyclonal antibodies against human Ig L-chains . In the other system, human T-lymphoma cells (Jurkat line) were treated successively with monoclonal antibodies against cell surface CD5 antigen and further on--with polyclonal antibodies against mouse Ig . In both systems, only a slight inhibition of the target cells' growth was registered . The probable reasons of low cytotoxic activity of the chimeric protein and prospects of increasing it are discussed.

J Gen Microbiol, 1991 Sep, 137 ( Pt 9), 2223 - 9
Purification and properties of extracellular lipase from Pseudomonas aeruginosa EF2; Gilbert EJ et al.; Extracellular lipase was purified from a Tween 80-limited continuous culture of Pseudomonas aeruginosa EF2 by ultrafiltration of the culture supernatant followed by anion-exchange and gel-filtration FPLC . The lipase was composed of a single subunit (Mr 29,000, pI 4.9), which was capable of a variable degree of aggregation, and which exhibited both lipase activity, measured with the insoluble substrate olive oil (predominantly triolein), and esterase activity, measured with the soluble substrates p-nitrophenyl acetate and Tween 80 . Lipase activity was approximately eight times higher than either type of esterase activity (kcat approximately 3000 s-1 for the hydrolysis of olive oil) . The enzyme showed a marked regiospecificity for the 1,3-oleyl residues of radiolabelled triolein, was relatively stable at moderate temperatures (exhibiting a biphasic loss of activity with an initial t1/2 of 17.5 min at 60 degrees C) and was very stable to freezing and thawing . Lipase activity was only weakly inhibited by the serine-active reagent 3,4-dichloroisocoumarin, and was not inhibited by the chelating agent EDTA (1 mM) . The N-terminal amino acid sequence of the Ps . aeruginosa EF2 lipase showed a marked similarity to those of several other bacterial lipases.

J Gen Microbiol, 1991 Sep, 137 ( Pt 9), 2215 - 21
Physiological regulation and optimization of lipase activity in Pseudomonas aeruginosa EF2; Gilbert EJ et al.; Physiological regulation of extracellular lipase activity by a newly-isolated, thermotolerant strain of Pseudomonas aeruginosa (strain EF2) was investigated by growing the organism under various conditions in batch, fed-batch and continuous culture . Lipase activity, measured as the rate of olive oil (predominantly triolein) hydrolysis, was weakly induced by general carbon and/or energy limitation, strongly induced by a wide range of fatty acyl esters including triglycerides, Spans and Tweens, and repressed by long-chain fatty acids including oleic acid . The highest lipase activities were observed during the stationary phase of batch cultures grown on Tween 80, and with Tween 80-limited fed-batch and continuous cultures grown at low specific growth rates . The lipase activity of Tween 80-limited continuous cultures was optimized with respect to pH and temperature using response surface analysis; maximum activity occurred during growth at pH 6.5, 35.5 degrees C, at a dilution rate of 0.04 h-1 . Under these conditions the culture exhibited a lipase activity of 39 LU (mg cells)-1 and a specific rate of lipase production (qLipase) of 1.56 LU (mg cells)-1 h-1 (1 LU equalled 1 mumol fatty acid released min-1) . Esterase activity, measured with p-nitrophenyl acetate as substrate, varied approximately in parallel with lipase activity under all growth conditions, suggesting that a single enzyme may catalyse both activities.

Am J Physiol, 1991 Sep, 261(3 Pt 2), R536 - 42
Skeletal muscle amino acid and myofibrillar protein mRNA response to thermal injury and infection; Fong YM et al.; Skeletal muscle changes associated with severe injury were investigated in male Wistar rats subjected to 30% full thickness scald injury (burn) and thermal injury followed by immediate colonization with 10(8) colony-forming units of Pseudomonas aeruginosa (BI) . Freely fed animals (FF) and animals pair fed to the BI animals (PF) served as controls . Thermal injury in conjunction with infection produced a rapid and sustained muscle cellular membrane depolarization (transmembrane potential difference at 12 h after injury: FF 92.1 +/- 0.3 and BI 85.2 +/- 2.3 mV; P less than 0.05) . This was followed by body weight loss and skeletal muscle protein wasting (gastrocnemius protein at 7 days: FF 0.35 +/- 0.01 and BI 0.16 +/- 0.03 g; P less than 0.05) and intracellular high-energy phosphate depletion (ATP at 10 days: FF 6.6 +/- 0.4 and BI 4.5 +/- 0.4 mumol/g tissue; P less than 0.05) . These body and cellular changes were not accounted for by the anorexia alone . Marked alterations in intracellular free amino acids were also noted in the BI group characterized by increases in levels of all amino acids (total intracellular free amino acids at 7 days: FF 51 +/- 7 and BI 91 +/- 12 mM; P less than 0.05) except intracellular glutamine (at 7 days: FF 6.0 +/- 0.2 and BI 2.4 +/- 0.6 mM; P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Infect Immun, 1991 Sep, 59(9), 3219 - 26
Cloning and sequencing of the genes coding for the 10- and 60-kDa heat shock proteins from Pseudomonas aeruginosa and mapping of a species-specific epitope; Sipos A et al.; A genomic library of Pseudomonas aeruginosa DNA was screened with a monoclonal antibody (MAb 2528) specific for the P . aeruginosa 60-kDa heat shock protein . A positive clone, pAS-1, was isolated . The gene coding for P . aeruginosa chaperonin (hsp60) was localized to a 2-kb EcoRI fragment subcloned in pAS-2 . A sequence analysis of pAS-2 and parts of pAS-1 identified two open reading frames that encoded proteins with calculated molecular masses of 10 and 57 kDa . In amino acid sequence comparison studies the sequences of these proteins, which were designated GroES and GroEL, exhibited up to 78% homology with known prokaryotic sequences of 10- and 60-kDa heat shock proteins (hsp10 and hsp60) . In order to map the epitope recognized by MAb 2528, a series of GroEL nested carboxy-terminal deletion clones were tested with MAb 2528 . We identified the clone with the shortest insertion that was still recognized by MAb 2528 and the clone with the largest insertion that was not recognized by MAb 2528 . The 3' ends of the insertions were determined by sequencing and were found to delimit a region that encoded 25 amino acid residues . Synthetic oligonucleotides that coded for peptides possibly resembling the epitope within this region were ligated into expression vector pGEX-3X, and fusion proteins expressed by these clones were tested for reactivity with MAb 2528 . By using this method we determined that the decapeptide QADIEARVLQ (positions 339 to 348 on GroEL) was responsible for the binding of P . aeruginosa-specific MAb 2528.

Infect Immun, 1991 Sep, 59(9), 2859 - 63
Pseudomonas aeruginosa exoenzyme S is an adhesion; Baker NR et al.; Exoenzyme S from Pseudomonas aeruginosa has been studied as an adhesion for glycosphingolipids and buccal cells . Binding of exoenzyme S to gangliotriosylceramide (GalNAc beta 1-4Gal beta 1-4Glc beta 1-1Cer), gangliotetraosylceramide (Gal beta 1-3 GalNAcT beta 1-4 Gal beta 1-4Glc beta 1-1Cer), and lactosylceramide (Gal beta 1-4Glc beta 1-1Cer) separated on thin-layer chromatograms was observed . Binding curves for exoenzyme S with dilutions of gangliotetraosylceramide immobilized on plastic plates were similar to previously reported results for the intact bacteria . Binding of exoenzyme S to sialylated counterparts of these glycosphingolipids was not seen, indicating that the addition of a sialic acid residue interferes with binding . Exoenzyme S and monoclonal antibody to exoenzyme S inhibit the binding of P . aeruginosa to buccal cells . The presence of exoenzyme S on the surface of P . aeruginosa was detected by immunogold labeling of bacteria with antibodies to exoenzyme S . Results of these studies led us to conclude that exoenzyme S is an important adhesion of P . aeruginosa.

Infect Immun, 1991 Sep, 59(9), 3316 - 8
Production of leukotriene B4 and 5-hydroxyeicosatetraenoic acid by human neutrophils is inhibited by Pseudomonas aeruginosa phenazine derivatives; Muller M et al.; Pyocyanin, a phenazine pigment produced by Pseudomonas aeruginosa, and its metabolite 1-hydroxyphenazine inhibited leukotriene B4 and 5-hydroxyeicosatetraenoic acid production by up to 70% in human neutrophils stimulated with the calcium ionophore A23187 (5 microM) . This potential anti-inflammatory effect was dose dependent and occurred at low concentrations (10 to 50 microM) that did not inhibit neutrophil viability.

Clin Chim Acta, 1991 Aug 30, 200(2-3), 119 - 27
Mechanized assay of plasma prekallikrein by activation with Pseudomonas aeruginosa elastase and amidolysis of chromogenic substrate; Shibuya Y et al.; An automated assay of plasma prekallikrein is described . Prekallikrein was converted to kallikrein with Pseudomonas aeruginosa elastase, and the hydrolytic activity of kallikrein to H-D-Pro-Phe-Arg-paranitroanilide subsequently measured . The conversion was complete within 8 minutes and the amidolytic activity remained stable at least another 10 min at 37 degrees C . This method worked in plasma deficient in Hageman factor (blood coagulation factor XII) . Using anti-prekallikrein antibody and plasma deficient in prekallikrein, the amidolytic activity generated in normal plasma was identified as due to kallikrein . With plasma samples, the coefficients of variation (CV) for multiple measurements within run (n = 10) and between run (n = 10) were as low as 5.0% and 6.6%, respectively, and the minimum measurable concentration of prekallikrein in plasma was 10% of the normal level.

Biochem Biophys Res Commun, 1991 Aug 15, 178(3), 1043 - 8
Ofloxacin-resistant Pseudomonas aeruginosa mutants with elevated drug extrusion across the inner membrane; Lei Y et al.; We selected the quinolone-resistant mutants from the protein F deficient Pseudomonas aeruginosa . The mutants showed cross-resistance to tetracycline, minocycline and chloramphenicol, but not to the beta-lactam antibiotics . The MIC of ofloxacin (OFLX) against the mutants, but not in the parent, became 2 to 4 times lower as the medium pH was raised from 6.5 to 8.5 . The mutants accumulated about half as much OFLX as the parent . The OFLX accumulation in the mutants increased 6.5- to 8-fold in the presence of 100 mM carbonyl cyanide m-chlorophenylhydrazone, while that in the parent was 4-fold . The OFLX sensitivity of the mutant DNA-gyrase was comparable with that of the parent's enzyme . These results suggest that the resistance of these mutants to OFLX is associated with the membrane potential dependent drug efflux.

J Bacteriol, 1991 Aug, 173(15), 4700 - 6
Isolation and characterization of catabolite repression control mutants of Pseudomonas aeruginosa PAO; Wolff JA et al.; Independently controlled, inducible, catabolic genes in Pseudomonas aeruginosa are subject to strong catabolite repression control by intermediates of the tricarboxylic acid cycle . Mutants which exhibited a pleiotropic loss of catabolite repression control of multiple pathways were isolated . The mutations mapped in the 11-min region of the P . aeruginosa chromosome near argB and pyrE and were designated crc . Crc- mutants no longer showed repression of mannitol and glucose transport, glucose-6-phosphate dehydrogenase, glucokinase, Entner-Doudoroff dehydratase and aldolase, and amidase when grown in the presence of succinate plus an inducer . These activities were not expressed constitutively in Crc- mutants but exhibited wild-type inducible expression.

Zh Mikrobiol Epidemiol Immunobiol, 1991 Aug, (8), 30 - 3
{A comparative analysis of the antibacterial activity of antiseptics and antibiotics on samples of Pseudomonas aeruginosa}; Krasil'nikov AP et al.; Antibiotic and antiseptic preparations, currently used in medical practice, have been tested on the same P . aeruginosa samples and compared by the amplitude of their minimal inhibiting concentration (MIC) values, determined as the average MIC values for the samples under test, by the proportion of variants resistant to the tested preparations, by the distribution of strains in the resistance spectrum, and by the pace of the increase of resistant variants under natural conditions in 5-10 years . On the basis of the results obtained in this study a conclusion has been made that in some cases of local application antiseptic preparations have advantages over antibiotics, especially in controlling hospital strains of microorganisms . The authors believe that the heterogeneity of microbial populations, as well as the frequency of the appearance of resistant variants and the activity of the mechanisms of their selection in hospitals, is of great importance in the development of new preparations, in the re-evaluation of currently used preparations and in the choice of the optimum preparation in concrete situations.

FEMS Microbiol Immunol, 1991 Aug, 3(4), 185 - 92
A Pseudomonas aeruginosa alginate-exotoxin A conjugate that elicits anti-alginate and exotoxin A-neutralizing antibodies; Coin D et al.; Pseudomonas aeruginosa alginate was covalently coupled to exotoxin A by reductive amination using adipic acid dihydrazide as spacer . The conjugate was composed of 25% alginate and 75% exotoxin A and possessed an average molecular mass higher than 700 kDa as determined by polyacrylamide gel electrophoresis . The conjugate had virtually no ADP-ribosyltransferase activity and a reduced cytotoxicity for TSA8 murine cells, derived from Friend erythroleukemia cells, as indicated by a greater than 50-fold increased LD50 . Anti-conjugate antibodies recognized exotoxin A and alginate . A booster injection resulted in markedly increased antibody ELISA titers to both exotoxin A and alginate . The antibodies neutralized the exotoxin A toxicity.

Am J Vet Res, 1991 Aug, 52(8), 1285 - 7
Kinetic study of serum gentamicin concentrations in baboons after single-dose administration; Watson JR et al.; This study establishes preliminary pharmacokinetic data on the use of gentamicin sulfate administered IM to baboons . Serum concentrations greater than or equal to 12 micrograms/ml are generally agreed to cause toxicosis in human beings . On the basis of preliminary test results suggesting that the manufacturer's recommended dosage for dogs of 4.4 mg/kg of body weight caused potentially toxic serum concentrations, a dosage of 3 mg/kg was chosen to conduct a single-dose kinetic study in 6 baboons . Using a single-compartment model, the gentamicin serum half-life for IM administration of 3 mg of gentamicin/kg was 1.58 hours, and serum concentrations remained below the potentially toxic concentrations reported for human beings . We suggest that a dosage of 3 mg/kg is safer than a dosage of 4.4 mg/kg administered IM to baboons . Minimal inhibitory concentrations for 2 Pseudomonas aeruginosa isolates were less than or equal to 1 micrograms/ml . On the basis of our measured elimination half-life of 1.58 hours, it is reasonable to suppose that dosing q24 h will be inadequate to maintain therapeutic serum concentrations . We calculate that serum concentrations will remain at or above our measured minimal inhibitory concentration for P aeruginosa (1 micrograms/ml) for 100% of the treatment time if the animal is dosed q 6h, 78% for dosing q 8h, and 52% for dosing q 12h . Therefore, we suggest 3 mg/kg, q 8h or q 6h as appropriate dosing schedules for the use of gentamicin sulfate administered IM to baboons.

Jpn J Antibiot, 1991 Aug, 44(8), 886 - 98
{Clinical evaluation of imipenem/cilastatin sodium as a second line regimen in severe infections associated with hematologic disorders}; Tsuda S et al.; Imipenem/cilastatin sodium (IPM/CS), which has a broad spectrum of activity against both Gram-positive and -negative bacteria including methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa, was used as the second choice for severe infections associated with hematological disorders . Sixty-five patients were treated with IPM/CS . Among them, 53 patients were evaluable for the clinical efficacy . Twelve patients were not evaluable due to the following reasons: 5 patients were treated with combinations of other regimens such as cefzonam, cefmenoxime, ciprofloxacin or gamma-globulin, 5 were patients to whom IPM/CS was administered as the first choice, and the remaining 2 patients were thought to be suffering not from febrile infections but from febrile tumor . Excellent responses were observed in 10 (18.9%) patients and good responses in 23 (43.4%) patients, with an overall rate of efficacy of 62.3% . The efficacy in septic patients was 75% (3/4), and that in patients whose peripheral granulocytes were continuously below 100/microliter was also 75% (6/8) . Two patients who suffered from tumor fever and 5 patients who had received no chemotherapy before IPM/CS administration were included in the final evaluation of side effects . Side effects were observed in 16 patients (16/60, 26.7%) . In a 61 years, female patient, a skin eruption was found 4 days after IPM/CS therapy was started . In 15 patients, mild gastrointestinal symptoms such as nausea and vomiting were identified within a few days after IPM/CS treatment was started . Abnormal laboratory data such as eosinophilia, liver dysfunction or renal dysfunction were also identified in 4 patients (4/60, 6.7%) . Degrees of these abnormalities were very slight, however, and the continuation of treatment was not disturbed . These results indicated that IPM/CS was an effective second line regimen of chemotherapy for the treatment of severe infections in patients with hematological disorders.

Ann Otol Rhinol Laryngol, 1991 Aug, 100(8), 632 - 7
Oral ofloxacin therapy for invasive external otitis; Zikk D et al.; The clinical efficacy and safety of orally administered ofloxacin (400 mg twice daily) were evaluated in 24 adult patients (17 men and 7 women; mean age, 65.8 years) with pseudomonal invasive external otitis (IEO) . The patients were divided into two groups: group A, (n = 9) suffering from a mild form of IEO, and group B (n = 15), suffering from a more severe form of the disease . Diabetes mellitus was the main underlying disease in these patients . Pseudomonas aeruginosa was the only pathogen in 18 infected ears and part of the polymicrobial flora in an additional 6 . Cure was observed in 83.3% of the patients . Two of the cured patients required more than one course of ofloxacin treatment . Development of P aeruginosa resistant to ofloxacin (n = 3) and severe allergic reaction (n = 1) required the discontinuation of ofloxacin therapy . Other side effects such as nausea, arthralgia, and vaginal itching were minimal . Oral administration of ofloxacin seems to be an effective, convenient, relatively safe, and economical therapy of IEO caused by the susceptible organism.

J Bacteriol, 1991 Aug, 173(16), 5136 - 43
AlgR, a response regulator controlling mucoidy in Pseudomonas aeruginosa, binds to the FUS sites of the algD promoter located unusually far upstream from the mRNA start site; Mohr CD et al.; Strong transcriptional activation of algD, a key event in the overproduction of alginate and establishment of mucoidy in Pseudomonas aeruginosa, depends on the functional algR gene . The predicted gene product of algR shows homologies to response regulators from bacterial signal transduction systems . The algR gene was overexpressed in Escherichia coli, its product (AlgR) was purified by utilizing its apparent affinity for heparin, and its sequence was verified by partial amino acid sequence analysis . AlgR was found to interact directly with the algD promoter . Deletion mapping analysis, in conjunction with mobility shift DNA-binding assays, indicated the presence of three regions within the algD promoter capable of specifically binding AlgR . A relatively weak interaction was observed with the algD promoter fragment containing the region immediately upstream of the algD mRNA start site (-144 to +11) . However, when fragments spanning regions located very far upstream from the algD mRNA initiation site (-533 and -332) were used, strong specific binding was observed . These regions were separated by a DNA segment not binding AlgR and spanning positions -332 to -144 . DNase I footprinting analysis further established the presence of discrete AlgR binding sites overlapping with FUS, the far-upstream sites required for full induction of algD transcription and its environmental modulation . There were two distinct binding sites: RB1, spanning nucleotides -479 to -457, and RB2, spanning nucleotides -400 to -380 . Both of these sequences shared a highly conserved core region, ACCGTTCGTC . These results established a direct interaction of AlgR with the algD promoter and revealed an arrangement of binding sites highly unusual for response regulators of the AlgR type.

J Bacteriol, 1991 Aug, 173(16), 4914 - 21
Cloning and DNA sequence of amiC, a new gene regulating expression of the Pseudomonas aeruginosa aliphatic amidase, and purification of the amiC product; Wilson S et al.; Using in vitro-constructed deletions and subcloned DNA fragments, we have identified a new gene, amiC, which regulates expression of the inducible Pseudomonas aeruginosa aliphatic amidase activity . The DNA sequence of the gene has been determined, and an open reading frame encoding a polypeptide of 385 amino acids (molecular mass, 42,834 Da) has been identified . A search of sequence libraries has failed to find homologies with other published sequences . The amiC translation termination codon (A)TGA overlaps the initiation codon for the downstream amiR transcription antitermination factor gene, implying that the amiCR operon is coordinately regulated . Disruption of the amiC open reading frame by insertion and deletion leads to constitutive amidase synthesis, suggesting that AmiC is a negative regulator . This is confirmed by the finding that a broad-host-range expression vector carrying amiC (pSW41) represses amidase expression in a series of previously characterized P . aeruginosa amidase-constitutive mutants . The AmiC polypeptide has been purified from PAC452(pSW41), and N-terminal amino acid sequencing has confirmed the gene identification.

J Bacteriol, 1991 Aug, 173(15), 4742 - 50
Anaerobic regulation of transcription initiation in the arcDABC operon of Pseudomonas aeruginosa; Gamper M et al.; The arcDABC operon of Pseudomonas aeruginosa encodes the enzymes of the arginine deiminase pathway, which is inducible under conditions of oxygen limitation and serves to generate ATP from arginine . The 5' end of arc mRNA extracted from anaerobically grown cells was determined by S1 and primer extension mapping . The transcription initiation site was located upstream of the arcD gene and 41.5 bp downstream of the center of the sequence TTGAC....ATCAG . This sequence, termed the ANR box, is similar to the consensus FNR recognition site of Escherichia coli . Transcription of the arc operon in P . aeruginosa was strongly decreased by a deletion of the TTGAC half site or by a mutation in the anr gene, which is known to code for the FNR-like regulatory protein ANR . During a transition from aerobic to anaerobic growth conditions, the concentrations of arc mRNAs and the levels of the ArcD and ArcA proteins rose in a parallel fashion . Mutational analysis of the arc promoter region led to the conclusion that the distance between the ANR box and the -10 promoter region is important for promoter strength, whereas the -35 region does not appear to be critical for arc promoter function . These findings and previous results indicate that anaerobic induction of the arc operon occurs at the level of transcription and requires the ANR box in cis and the ANR protein in trans.

Laryngoscope, 1991 Aug, 101(8), 821 - 4
Ciprofloxacin: drug of choice in the treatment of malignant external otitis (MEO); Levenson MJ et al.; Ciprofloxacin, a fluorinated quinolone with high efficacy against Pseudomonas aeruginosa, was used in the treatment of 10 consecutive patients with malignant external otitis . All patients had skull base osteomyelitis documented by nuclear and computed tomography (CT) scans . Dosages of 1.5 g of ciprofloxacin daily were used for a mean average of 10 weeks . All patients were considered cured with a minimum follow-up of 18 months after completion of therapy . A new classification of malignant external otitis (MEO) is presented.

Am Rev Respir Dis, 1991 Aug, 144(2), 331 - 7
Predictive value of oropharyngeal cultures for identifying lower airway bacteria in cystic fibrosis patients; Ramsey BW et al.; Identifying lower respiratory pathogens in young, non expectorating cystic fibrosis (CF) patients has been problematic . Bronchial secretions are difficult to obtain, and little is known about lower airway flora in these patients . We collected simultaneous bronchial and oropharyngeal specimens in 43 CF patients in optimal respiratory status, including both expectorating (17) and nonexpectorating (26) patients, to determine the predictive value of oropharyngeal cultures for identifying lower airway pathogens . An additional goal was to characterize the lower respiratory flora of these patients . Predictive values were defined as the proportion of oropharyngeal culture results that accurately reflected the results of bronchial cultures . Predictive values of positive oropharyngeal cultures in nonexpectorating patients were 83% (95% confidence interval 36 to 100%) for Pseudomonas aeruginosa and 91% (59 to 100%) for Staphylococcus aureus . Predictive values of negative oropharyngeal cultures were lower: 70% (48 to 86%) for R aeruginosa and 80% (52 to 96%) for S . aureus . A relatively high proportion of nonexpectorating CF patients less than 10 yr old had R aerusginosa (11 of 24, 46%) or Klebsiella species (5 of 24, 21%) in their lower airways . The isolation of Klebsiella was associated with younger age (p = 0.03) and recent administration of antistaphylococcal antibiotics (p = 0.05) . Our results suggest that oropharyngeal cultures yielding R aeruginosa or S . aureus are highly predictive, but such cultures lacking these organisms do not rule out the presence of these pathogens in the lower airways of CF patients.

Can J Microbiol, 1991 Aug, 37(8), 654 - 7
Siderophore synthesis by mucoid Pseudomonas aeruginosa strains isolated from cystic fibrosis patients; Haas B et al.; Nonmucoid Pseudomonas aeruginosa responds to iron deprivation by synthesizing the siderophores pyochelin and pyoverdine . When grown in iron-deficient medium, six mucoid P . aeruginosa strains isolated from cystic fibrosis patients synthesized copious amounts of the exopolysaccharide alginate . A procedure that eliminated the interference of alginate was developed so that siderophores could be extracted from the growth medium . All six isolates were then noted to produce both pyoverdine and pyochelin . This report thus confirms that mucoid P . aeruginosa, like its nonmucoid counterparts, elicits the siderophores commonly cited as those of the microbe.

Antonie Van Leeuwenhoek, 1991 Aug, 60(2), 83 - 6
R-bodies in Pseudomonas aeruginosa strain 44T1; Espuny MJ et al.; For the first time R-bodies are described in a new strain 44T1 of Pseudomonas aeruginosa . Its size was measured as being 0.22 to 0.37 microns of width per 0.27 to 0.41 microns of length and 5 to 9 spiral turns about 16 nm . These structures are similar to previously observed in bacteria and are related with physiological state of bacteria in minimal conditions of growth.

J Antimicrob Chemother, 1991 Aug, 28(2), 199 - 207
Role of OmpD2 and chromosomal beta-lactamase in carbapenem resistance in clinical isolates of Pseudomonas aeruginosa; Satake S et al.; Imipenem-resistant clinical isolates of Pseudomonas aeruginosa were divided into two categories: (i) isolates that were moderately resistant to imipenem (MIC 6.25 mg/L) that produced trace amounts of protein D2 detected with immunoblotting using anti-protein D2 antibody, but not when stained with Coomassie blue and had inducible class 1 beta-lactamase expression; (ii) isolates that were highly resistant to several beta-lactams, including meropenem, with no protein D2 by staining or immunoblotting and had stably derepressed beta-lactamase . Laboratory strains were isolated and analyzed: (i) mutants lacking protein D2, or (ii) lacking protein D2 and producing stably derepressed beta-lactamase with carbapenem resistance similar to the clinical isolates . (iii) mutants producing undetectable beta-lactamase which were four-fold more susceptible to imipenem than the mutant producing stably derepressed beta-lactamase or the strain with inducible beta-lactamase . These data suggests that beta-lactamase and outer membrane permeability govern meropenem-resistance in P . aeruginosa.

Singapore Med J, 1991 Aug, 32(4), 211 - 3
Serodiagnosis of melioidosis in Singapore by the indirect haemagglutination test; Yap EH et al.; Melioidosis is endemic in Singapore, with diagnosis dependent upon both bacteriological culture and serodiagnosis . Using the polysaccharide (melioidin)-sensitized turkey red cells in the indirect haemagglutination test (IHAT), 20 (100%) of the Pseudomonas pseudomallei culture-positive cases were detectable by the IHAT with titles ranging from 1:16 to 1:32, 768 . Eight of these patients who died within a few days after the IHAT was performed had titres ranging from 1:16 to 1:1028 . Five culture-negative patients, with clinical symptoms suggestive of melioidosis infection and who responded to treatment with ceftazidime, showed IHA titres between 1:64 and 1:8,192 . One hundred and twenty one sera from patients with pneumonia, abscesses, or diabetes mellitus were IHAT negative . The IHAT showed good specificity since negative titres were seen in tests using sera from 2 patients with culture-positive Pseudomonas aeruginosa and 4 patients positive for Legionella . IHAT negative results were obtained from tests of 50 normal blood donors and 50 sewerage workers . Of 683 national servicemen tested, 5 (0.73%) had IHAT titres ranging from 1:16 to 1:128 . Unlike hyperendemic areas such as Thailand where interpretation of IHAT is seriously hampered by IHA titres found in one-third to half of the population, serodiagnosis of melioidosis by the sensitive IHAT may be employed in Singapore as a routine procedure since background IHA titres are low.

Mol Microbiol, 1991 Aug, 5(8), 2003 - 10
Pseudomonas aeruginosa LasA: a second elastase under the transcriptional control of lasR; Toder DS et al.; The full elastolytic phenotype of Pseudomonas aeruginosa requires lasB, the structural gene for elastase, its transcriptional activator lasR, and lasA . The lasB gene was insertionally inactivated with the omega fragment and this mutated gene introduced into the P . aeruginosa chromosome . Replacement of the wild-type gene with the inactivated gene was verified by Southern analysis and confirmed by lack of elastase antigen on Western blots and lack of activity in liquid assays . The mutant did, however, retain elastolytic activity on elastin plates . This residual activity was abolished by inactivation of lasB in PAO-E64, a lasA-deficient mutant, demonstrating that it was due to the lasA gene product . Northern analysis demonstrated that, like lasB, lasA is transcriptionally controlled by the lasR gene product.

Antibiot Khimioter, 1991 Aug, 36(8), 39 - 42
{Antimicrobial activity of piperacillin in vitro}; Skala LZ et al.; There was an increase in the resistance of clinical isolates to piperacillin as compared to that in 1987-1988 . It was shown on the kinetic models that there was difference in the effect of the inhibitory and subinhibitory concentrations of the drug on microorganisms in various growth phases . No post-antibiotic action against Staphylococcus aureus and Pseudomonas aeruginosa and a slightly pronounced dose-dependent effect with respect to Escherichia coli were noted.

Appl Environ Microbiol, 1991 Aug, 57(8), 2345 - 50
Plasmids of Pseudomonas cepacia strains of diverse origins; Lennon E et al.; Thirty-seven strains of Pseudomonas cepacia from clinical, pharmaceutical-industrial, and environmental origins were analyzed for the presence of plasmid DNA by a modification of the rapid alkaline extraction method of Birnboim (H . C . Birnboim, Methods Enzymol . 100:243-255, 1983) . Plasmids were present in 31 strains (84%) from all sources, with no one source showing less than 75% plasmid carriage among its strains . The plasmid profiles indicated that the presence of large plasmids (146 to 222 kb) was the norm . Those strains with greater antibiotic resistance were mainly in the clinical and pharmaceutical groups and carried large plasmids (222 kb) that appeared essentially identical by restriction digest analysis . The ability for conjugative transfer was shown with the broad-host-range plasmid R751 carrying the gene for resistance to trimethoprim, one of the few antimicrobial agents effective against P . cepacia . The plasmid was transferred from Pseudomonas aeruginosa to P . cepacia strains as well as from P . cepacia transconjugants to other P . cepacia strains.

Zh Mikrobiol Epidemiol Immunobiol, 1991 Aug, (8), 59 - 61
{The serological characteristics of the O antigens of Pseudomonas aeruginosa isolated from patients with a Pseudomonas infection during immunotherapy}; Kholodkova EV et al.; Serologic characteristics of P . aeruginosa O-antigens isolated from patients with P . aeruginosa infection were studied over the course of treatment with anti-P . aeruginosa sheep immunoglobulin . The preparation was used in 54 patients with nongeneralized forms of P . aeruginosa infection (infected wounds, pleural empyema) externally or intraperitoneally . From the clinical material collected from the patients a total of 54 P . aeruginosa strains were isolated . Serologic typing of the isolated strains with factor or group diagnostic agglutinating sera has revealed the O-group composition of the isolated strains; 66% of them were classified with O-groups 2,3, and 6 . Serologic variants of the strains isolated from patients proved to be stable over the course of the disease immunotherapy . Analysis of the results of bacteriologic control of immunotherapy . efficacy and the clinical data has demonstrated the efficacy of immunotherapy in 61.1% of cases and its partial effect in 20.4% of cases of P . aeruginosa infection.

J Hosp Infect, 1991 Aug, 18(4), 301 - 6
Vegetables as a source of infection with Pseudomonas aeruginosa in a University and Oncology Hospital of Rio de Janeiro; Correa CM et al.; Samples of fresh vegetables fed to patients in an Oncology and a University Hospital were examined for frequency of recovery and counts of Pseudomonas aeruginosa . Thirty-eight isolates from vegetables as well as 98 clinical isolates recovered during the same period of vegetable collection were serotyped and assayed for pyocin production in order to evaluate the role of vegetables as a source of microorganisms . Pseudomonas aeruginosa was recovered from 19.0% of the vegetable samples . Although 1% hypochlorite solution was used as a sanitizer, 50% of the positive samples were found to harbour more than 100 colony-forming units (cfu) g-1 . Lettuce, chicory and watercress yielded the highest frequencies of isolation (P less than 0.05) . The pyocin typing and serotyping of clinical strains revealed some types identical to those recovered from vegetables . Among those found in the University Hospital, serotype O4 and pyocin type PT10/b were detected in vegetables and in clinical specimens whereas types O1-PT22/e, O2a-PT10/a, O2a-PT10/b, O4-PT10/a, O11-PT10/a and O11-PT10/b were common in both groups of strains isolated in the Oncology Hospital . Our results strongly suggest that vegetables represent a source of endemic infection with P . aeruginosa for hospitalized patients.

Surgery, 1991 Aug, 110(2), 205 - 11; discussion 211-2
Anti-CD18 antibody attenuates neutropenia and alveolar capillary-membrane injury during gram-negative sepsis; Walsh CJ et al.; Activated polymorphonuclear leukocytes (PMNs) are implicated in the pathogenesis of acute lung injury (ALI) associated with sepsis . Adhesion of activated PMNs to endothelial monolayers is mediated by the CD18 adhesion-receptor complex on the PMN cell surface . Monoclonal antibody 60.3 (MoAb 60.3) blocks CD18-dependent PMN-endothelial adhesion in vitro and in vivo . This study was designed to determine the role of CD18-dependent PMN adhesion in ALI associated with gram-negative sepsis . Anesthetized, ventilated (FiO2 0.5, positive end-expiratory pressure 5 cm H2O) pigs received sterile saline (control, n = 8) or live Pseudomonas aeruginosa, 5 x 10(8) colony-forming units/ml at 0.3 ml/20 kg/min (septic, n = 9) for 1 hour . A third group (n = 7) received MoAb 60.3, 2 mg/kg intravenously, 15 minutes before Pseudomonas infusion . Animals were studied for 300 minutes . MoAb 60.3 significantly (p less than 0.05) attenuated the neutropenia seen in sepsis (15 +/- 1 vs 6 +/- 1 x 10(3) PMNs/mm3 at 300 min) . Alveolar-capillary membrane injury was assessed by bronchoalveolar-lavage protein content and extravascular lung water determination . MoAb 60.3 significantly (p less than 0.05) reduced BAL protein at 300 minutes (388 +/- 75 vs 1059 +/- 216 micrograms/ml in septic animals) and attenuated the increase in extravascular lung water to 240 minutes (7.1 +/- 2 vs 14.2 +/- 1.2 ml/kg in septic animals) . Systemic hypotension, decreased cardiac index, pulmonary hypertension, and relative hypoxemia, all characteristic of this model, were not altered by MoAb 60.3 . These data suggest that, in this model of septic ALI, neutropenia is, in part, CD18 dependent and that blocking CD18-dependent PMN adhesion protects the alveolar-capillary membrane independently of altered hemodynamic status.

Genetika, 1991 Aug, 27(8), 1324 - 35
{Features of genome expression of phage transposon D3112 of Pseudomonas aeruginosa in Escherichia coli bacteria: dependence of bacterial phenotype on copy number of D3112 genome}; Trenina MA et al.; Escherichia coli (RP4 :: D3112) bacteria manifest Tcs phenotype (thirty centigrade sensitivity), i.e . the cells do not divide and form colonies under conditions of lowered temperature (30 degrees C and lower), while cells grow normally at 42 degrees C . In this work it is demonstrated that replication-transposition of D3112 and the Tcs phenotype depend on no recA system of E.coli . Following events lead to the loss of the Tcs phenotype (in E.coli (RP4 :: D3112) cells survived after growing at 30 degrees C): occurrence of mutations in bacterial, phage and plasmid genomes, elimination of DNA of hybrid plasmid or RP4 DNA (a portion of DNA) as well as integration of the hybrid plasmid into bacterial chromosome . In the latter case, the E.coli (D3112) cells acquired the properties shared by the initial bacteria and those with the Tcs phenotype . Such clones are designated tcl (thirty centigrade low sensitivity), they are able to form colonies at 30 degrees C but their growth is more slow, they maintain instability at lowered temperature and continue to produce D3112 phage . The tcl clones in which replication-transposition of D3112 DNA in less effective than in the tcs clones are a suitable object for the study of genetic rearrangements caused by D3112 phage transposon . It is shown that either complete RP4 genome or its portion are comprised between direct repeats of D3112 and are built into various chromosomal sites, i.e . cointegrates are being formed . Two types of deletions are revealed: eliminating sites of RP4 plasmid adjacent to the left end of D3112 genome as well as deletions of the D3112 genome . It is demonstrated that alteration in the growth nature of E.coli, carrying D3112 DNA, at 30 degrees C depends on the copy number of D3112 per bacterial cell.

FEMS Microbiol Lett, 1991 Aug 1, 66(2), 131 - 5
Pseudomonas aeruginosa cholinesterase and phosphorylcholine phosphatase: two enzymes contributing to corneal infection; Domenech CE et al.; Choline, acetylcholine and betaine used as the sole carbon, nitrogen or carbon and nitrogen source increase cholinesterase activity in addition to phosphorylcholine phosphatase and phospholipase C activities in Pseudomonas aeruginosa . The cholinesterase activity catalyses the hydrolysis of acetylthiocholine (Km approx . 0.13 mM) and propionylthiocholine (Km approx . 0.26 mM), but not butyrylthiocholine, which is a pure competitive inhibitor (Ki 0.05 mM) . Increasing choline concentrations in the assay mixture decreased the affinity of cholinesterase for acetylthiocholine, but in all cases prevented inhibition raised by high substrate concentrations . Considering the properties of these enzymes, and the fact that in the corneal epithelium there exists a high acetylcholine concentration and that Pseudomonas aeruginosa produces corneal infection, it is proposed that these enzymes acting coordinately might contribute to the breakdown of the corneal epithelial membrane.

Antimicrob Agents Chemother, 1991 Aug, 35(8), 1538 - 46
Persistence mechanisms in Pseudomonas aeruginosa from cystic fibrosis patients undergoing ciprofloxacin therapy; Diver JM et al.; The mechanisms of persistence to ciprofloxacin in nine sets of Pseudomonas aeruginosa strains isolated during ciprofloxacin therapy of chronic lung infections in cystic fibrosis patients were studied . Low to moderate levels of ciprofloxacin resistance developed in each case . Each set of pretherapy ciprofloxacin-susceptible, during-therapy ciprofloxacin-resistant, and posttherapy ciprofloxacin-susceptible isolates were shown to be genotypically related by using a radiolabeled epidemiological gene probe . All ciprofloxacin-resistant isolates were found to have altered susceptibilities to both nalidixic acid and various chemically unrelated antibiotics . Analysis of possible resistance mechanisms showed that the strains had altered outer membrane protein or lipopolysaccharide profiles . Complementation of possible DNA gyrase mutations with a plasmid-borne, wild-type Escherichia coli gyrA gene indicated that altered DNA gyrase was at least partly responsible for ciprofloxacin resistance in all strains tested . Attempts to generate ciprofloxacin-susceptible revertants in vitro showed that in some strains reversion was rapid in the absence of ciprofloxacin, while in other strains it was not possible to generate revertants . These data indicate that persistence of Pseudomonas aeruginosa to ciprofloxacin involves changes in DNA gyrase and is associated with pleiotropic changes in outer membrane proteins and lipopolysaccharide.

Biochim Biophys Acta, 1991 Jul 26, 1097(1), 23 - 7
Activation of human plasma prekallikrein by Pseudomonas aeruginosa elastase in vitro; Shibuya Y et al.; Human plasma prekallikrein, precursor of the bradykinin-generating enzyme, was activated in a purified system under a near physiological condition (pH 7.8, ionic strength I = 0.14, 37 degrees C) by Pseudomonas aeruginosa elastase which is a tissue-destructive metalloproteinase . Compared with that, Pseudomonas aeruginosa alkaline proteinase poorly activated it with a rate as low as less than one-twentieth of that of elastase . The activation by elastase was blocked with a specific inhibitor of elastase, HONHCOCH(CH2C6H5)CO-Ala-Gly-NH2 (10 microM) . Generation of kallikrein-like amidolytic activity was also observed in plasma deficient in Hageman factor by treatment with elastase, but was not in plasma deficient in prekallikrein . The kallikrein-like activity generated in Hageman factor deficient plasma as well as the generation process itself was indeed inhibited by anti-human prekallikrein goat antibody . These results suggest that the pathological activation of the kallikrein-kinin system might occur under certain clinical conditions in pseudomonal infections.

J Biol Chem, 1991 Jul 25, 266(21), 14088 - 94
Properties of the collagenous domain of the alpha 3(IV) chain, the Goodpasture antigen, of lens basement membrane collagen . Selective cleavage of alpha (IV) chains with retention of their triple helical structure and noncollagenous domain; Gunwar S et al.; A third chain, alpha 3(IV), of basement membrane collagen was recently discovered and was identified as the primary target for the autoantibodies of patients with Goodpasture syndrome (Saus, J., Wieslander, J., Langeveld, J . P . M., Quinones, S., and Hudson, B . G . (1988) J . Biol . Chem . 263, 13374-13380) . In the present study, this chain was excised in the form of a truncated promoter by cleavage of basement membrane with Pseudomonas aeruginosa elastase and characterized . The triple helical structure and NC1 domain were retained . Elastase selectively cleaved at a site within the triple helical domain of the alpha 3 chain that is distinct from the cleavage site of the alpha 1 and alpha 2 chains . The truncated alpha 3 chain was found to contain 1460 residues, of which 1225 comprise the collagenous domain, and is cross-linked within this domain by disulfide bonds, forming a high Mr complex (greater than 300,000) . Truncated protomers with a length of 340 nm corresponding to the theoretical length for the truncated alpha 3 chain were observed by electron microscopy as suprastructures in which the triple helical domains of three protomers were interwined . These protomers were also connected to each other and to the 140-nm protomers that appear to be comprised of the alpha 1 and alpha 2 chains . These results extended the known length of the alpha 3 chain by about 1000 residues and suggested that protomers of this chain self-associate through interactions between their triple helical domains and between their NC1 domains.

Gene, 1991 Jul 15, 103(1), 87 - 92
Improved broad-host-range lac-based plasmid vectors for the isolation and characterization of protein fusions in Pseudomonas aeruginosa; Schweizer HP; Several new broad-host-range vectors for the construction of protein fusions to the Escherichia coli lacZ gene have been developed . In all of the constructs, a multiple cloning site (MCS) containing unique restriction sites is located upstream of lac operon segments whose lacZ genes lack translational start signals . Some of the vectors (pPZ10, pPZ20 and pPZ30) also contain transcriptional terminators upstream of the MCS . The new vectors allow the fusion of genes to lacZ in all translational reading frames . Due to a higher copy number they allow direct screening in E . coli for weakly expressed foreign promoters . Their usefulness for gene analysis in Pseudomonas aeruginosa was demonstrated by construction and expression of a regA'::'lacZ-encoded protein fusion.

Biochem Biophys Res Commun, 1991 Jul 15, 178(1), 309 - 14
Proton resonance assignments for Pseudomonas aeruginosa ferrocytochrome c-551; Cai ML et al.; A comparison between two sets of resonance assignments for ferrocytochrome c-551 from Pseudomonas aeruginosa reveals that major differences can be explained by pH effects . In turn, these reveal side chain protonation events in c-551 that markedly influence spectra . The behavior of resonances in a homologous protein from Pseudomonas stutzeri help to clarify ambiguities in the P . aeruginosa case . A corrected and completed set of proline assignments is presented . Labile side chain protons in residue 47, which hydrogen bonds to the inner heme propionate, appear to be in fast exchange with the solvent.

Appl Environ Microbiol, 1991 Jul, 57(7), 2079 - 84
Quantitative assessment of the germicidal efficacy of ultrasonic energy; Scherba G et al.; Propagated (free-field) ultrasonic energy at a frequency of 26 kHz was used to expose aqueous suspensions of bacteria (Escherichia coli, Staphylococcus aureus, Bacillus subtilis, and Pseudomonas aeruginosa), fungus (Trichophyton mentagrophytes), and viruses (feline herpesvirus type 1 and feline calicivirus) to evaluate the germicidal efficacy of ultrasound . There was a significant effect of time for all four bacteria, with percent killed increasing with increased duration of exposure, and a significant effect of intensity for all bacteria except E . coli, with percent killed increasing with increased intensity level . There was a significant reduction in fungal growth compared with that in the controls, with decreased growth with increased ultrasound intensity . There was a significant reduction for feline herpesvirus with intensity, but there was no apparent effect of ultrasound on feline calicivirus . These results suggest that ultrasound in the low-kilohertz frequency range is capable to some degree of inactivating certain disease agents that may reside in water . The physical mechanism of inactivation appears to be transient cavitation.

J Mol Biol, 1991 Jul 5, 220(1), 9 - 12
Molecular size and symmetry of Pseudomonas aeruginosa catabolic ornithine carbamoyltransferase . An X-ray crystallography analysis; Marcq S et al.; The catabolic ornithine carbamoyltransferase (EC 2.1.3.3) from Pseudomonas aeruginosa, that shows allosteric behaviour, and a mutant version of this enzyme has been crystallized in several different crystal forms . All of these have been characterized by X-ray diffraction methods . A 4.5 A resolution data set has been collected on a triclinic crystal . Analysis of the data using the self-rotation function shows that 12 monomers associate to form a particle with cubic 23 point group symmetry.

Antibiot Khimioter, 1991 Jul, 36(7), 25 - 8
{Activity of fluoroquinolones studied on a model of suppurative meningoencephalitis caused by Pseudomonas aeruginosa in mice}; Padeiskaia EN et al.; Activity of four fluoroquinolones i.e . ofloxacin, enoxacin, pefloxacin and ciprofloxacin was studied on a model of purulent meningoencephalitis caused by intracerebral contamination of mice with P . aeruginosa . 900 mice were involved in the experiment . Ofloxacin and enoxacin were administered per os and pefloxacin and ciprofloxacin were injected subcutaneously . Ofloxacin, pefloxacin and ciprofloxacin were shown to be highly active . Enoxacin showed a low activity . ++Non-fluorinated quinolones were inactive in the model . The activity of the fluoroquinolones was compared with that of gentamicin and dioxidine.

Mol Microbiol, 1991 Jul, 5(7), 1577 - 83
Mucoid Pseudomonas aeruginosa in cystic fibrosis: signal transduction and histone-like elements in the regulation of bacterial virulence; Deretic V et al.; The profuse production of the exopolysaccharide alginate results in mucoidy, a critical virulence factor expressed by Pseudomonas aeruginosa during chronic respiratory tract infections in cystic fibrosis . Studies of the regulation of this pathogenic determinant have unravelled at least two levels of control, including bacterial signal transduction systems and histone-like elements . Although only in its initial phase, an understanding of the dual control of mucoidy may help to illuminate adaptive processes that depend on the combination of these regulatory factors . Integration of specific signals transduced by the two-component systems with inputs generated by the general state of bacterial nucleoids may govern the expression of certain virulence determinants and provide a framework facilitating selection of phenotypes successful under particular environmental conditions and selective pressures.

Antimicrob Agents Chemother, 1991 Jul, 35(7), 1284 - 90
Aminoglycoside resistance and aminoglycoside usage: ten years of experience in one hospital; Gerding DN et al.; For 10 years the 700-bed Minneapolis Veterans Affairs Medical Center has conducted a policy of carefully controlled aminoglycoside usage and monitoring of resistance of over 25,000 aerobic and facultative gram-negative bacillary isolates to the aminoglycosides . On two occasions during the 1980s, our experience of introducing amikacin at a high level of usage was associated with a significant reduction in resistance to gentamicin and tobramycin among gram-negative bacilli . Rapid reintroduction of gentamicin usage in 1982 after the first amikacin period was associated with a significant and rapid increase in gentamicin and tobramycin resistance . However, in 1986, gentamicin was again reintroduced to this institution at an initially modest level, and the percentage of usage of gentamicin was gradually increased over a 15-month period without a significant change in resistance to gentamicin, tobramycin, or amikacin while maintaining an overall 68% gentamicin usage and 30% amikacin usage . Aminoglycoside usage (measured as patient days) rose steadily from under 2,000 patient days per quarter in 1980 and 1981 to over 3,000 days per quarter in 1985 . Since 1985, usage has declined to under 2,500 patient days per quarter in 1990 . This usage rise and fall occurred during a steadily declining daily patient census that was 590 in 1980 and 465 in 1989 . A move to a new hospital building in June 1988 was associated with an additional significant decline in resistance to all aminoglycosides (P less than 0.05), continuing a trend that was evident for the year preceding the move . Resistance to aminoglycoside antibiotics is now at the lowest level in 10 years at this institution, with only one gram-negative organism, Pseudomonas aeruginosa, that exhibits more than 5% resistance to gentamicin and no gram-negative species that are more than 5% resistant to amikacin and tobramycin.

Nihon Kyobu Shikkan Gakkai Zasshi, 1991 Jul, 29(7), 893 - 9
{A case of diffuse panbronchiolitis, performed an open lung biopsy after improvement with 6 years medication}; Mimoto T et al.; A 51-year-old male was hospitalized in June 1983, complaining of productive cough and dyspnea . Diffuse panbronchiolitis (DPB) was diagnosed on the basis of the physical examination, chest roentgenogram, chest CT and transbronchial lung biopsy (TBLB) . The patient underwent surgery for chronic sinusitis and deviated nasal septum, and received Pseudomonas aeruginosa vaccine, ampicillin and erythromycin . He revealed a posterior mediastinal tumor in March 1989 . The clinical findings of DPB improved but open lung biopsy was performed on the occasion of surgery for the posterior mediastinal tumor . Pathologically, fibrosis and mild infiltration of mononuclear cells localized in the walls of respiratory bronchioli and in surrounding areas was recognized in addition to slight accumulation of foamy macrophages in interstitial spaces . These morphological findings, as well as the clinical findings, might suggest repair of DPB lesions.

FEMS Microbiol Lett, 1991 Jul 1, 65(3), 257 - 60
Protein and other compositional differences of the extracellular material from slimy and non-slimy colonies of non-mucoid Pseudomonas aeruginosa; Ross NW et al.; The composition of extracellular material produced by non-mucoid strains of Pseudomonas aeruginosa differed when grown on surfaces that either did or did not induce the formation of slime under conditions where the medium was identical . The nature of the changes in protein composition indicated that protein expression differed in the course of growth on the two surfaces, and hence that there were physiological consequences associated with growth under conditions which do or do not lead to slime formation . The compositional differences also included elevated levels in extracellular material from the slimy colonies of two virulence factors, protease and rhamnolipids.

Eur J Clin Microbiol Infect Dis, 1991 Jul, 10(7), 551 - 8
Comparison of two schedules of cefoperazone plus aztreonam in the treatment of neutropenic patients with fever; Bodey G et al.; Cancer patients were randomized to receive an every 4 hour or every 8 hour schedule of cefoperazone plus aztreonam during 617 febrile episodes . The overall response rate for the 478 evaluable episodes was 76% and there was no difference in response rate between the two schedules . The response rate was 79% for cases of pneumonia and 63% for cases of bacteremia . Only 50% of the microbiologically documented infections caused by gram-positive organisms responded whereas 95% of gram-negative infections, including all of those caused by Pseudomonas aeruginosa, responded . Response rates were lower among patients whose neutrophil counts decreased during therapy than among those whose neutrophil counts increased (64% vs . 85%, p = 0.008) . Side-effects that were possibly or probably related to antibiotic therapy were observed during 11% of the episodes . The most common side-effects were diarrhea and rashes including one case of Stevens-Johnson syndrome . Three patients developed a coagulopathy during therapy . Cefoperazone plus aztreonam proved to be an effective combination for treatment of gram-negative infections and fever of unknown origin in cancer patients and an every 8-hour schedule of administration was as effective as an every 4-hour schedule . Approximately half of the patients with gram-positive infections required additional antibiotics for successful therapy.

Vaccine, 1991 Jul, 9(7), 491 - 4
Clinico-immunological trials of Pseudomonas aeruginosa vaccine; Stanislavsky ES et al.; Pseudomonas aeruginosa vaccine (PV) containing predominantly cell-wall protein protective antigens was tested for safety and immunogenicity by immunization of 119 volunteers . The criteria for safety and immunogenicity were the absence of serious post-vaccinal reactions or complications either during immunization or 12 months later . There were mild (19 donors or 15.9%) and moderate (three donors or 2.5%) febrile reactions after immunization and in two volunteers the body temperature increased up to 38 degrees C, however it decreased to normal values within 24 h . We observed in 43 (36.1%) of volunteers mild and in five (4.2%) moderate local reactions which disappeared within 24 h . Using the ELISA and passive mouse protection test it was shown that PV induces the formation of specific antibodies . A high level of specific antibodies persisted for the 5-month period of observation . The antibody titres increased in 94-97% of volunteers and moreover in 45.6% the antibody titres (the number of ELISA units) increased 2.5-3-fold and more . Anti-P . aeruginosa plasma was used for the treatment of 46 patients with severe forms of P . aeruginosa infection (40 adults and six infants aged up to 2 years) and 87% of the patients recovered.

Jpn J Antibiot, 1991 Jul, 44(7), 736 - 47
{Cefepime in the treatment of patients with surgical infections}; Morimoto K et al.; Between March 1988 and June 1990, we gave cefepime to 5 subjects after surgery and studied the pharmacokinetics of the drug . In the same period, we treated 23 patients with surgical infections with the same drug and evaluated its clinical efficacy . In the pharmacokinetic study, 1 g was given intravenously to each individual over a 30 minutes period . The peak levels in the plasma, 59.9-118 micrograms/ml, were obtained at around the end of this time . The peak levels in the bile, 7.1-28.2 micrograms/ml, were reached at 1-5 hours after administration, depending on the patient . At hours 5 and 6, the range of plasma concentration was 3.7-12.3 micrograms/ml . In the 22 patients with surgical infections, clinical efficacy of the drug was excellent in 12, good in 5, fair in 1, and poor in 4, with an overall efficacy rate of 77% . The bacteriological response was evaluated in the 16 patients for whom the species of the probable causative organisms were identified . Those bacteria were eradicated in 10 patients, decreased in 3, and were persisted in 3, with an eradication rate of 63% . Against 5 strains of Escherichia coli isolated, the highest MIC was 0.05 micrograms/ml, and against 2 strains of Pseudomonas aeruginosa isolated, the MIC was 1.56 micrograms/ml, so this drug should be highly effective toward these species . Three strains of Staphylococcus aureus were isolated, one of which was resistant to methicillin . It was not eradicated.

Pediatr Infect Dis J, 1991 Jul, 10(7), 496 - 500
Pseudomonas aeruginosa cellulitis and ecthyma gangrenosum in immunocompromised children; Fergie JE et al.; Pseudomonas aeruginosa skin infections are generally considered to be secondary manifestations of disseminated disease . A retrospective analysis of all cases of P . aeruginosa skin infections seen at St . Jude Children's Research Hospital since 1962 revealed 16 episodes of the infection (ecthyma gangrenosum, 8 episodes, 7 patients; cellulitis, 8 episodes, 7 patients) in which blood cultures were uniformly negative for P . aeruginosa . All cases were identified while the patients were receiving ambulatory care . Five episodes developed while the patients' neutrophil counts were greater than 1 x 10(9) cells/liter . Eight patients had acute lymphoblastic leukemia, 2 had acute myeloid leukemia, 2 had aplastic anemia, 1 had transient agranulocytosis and 1 had cyclic neutropenia . There were no solid tumor patients . Although patients received different antibiotic combinations, all had resolutions of their lesions without fatal complications . Patients diagnosed as having cellulitis required a mean of 9.2 days of treatment with intravenous antibiotics, as compared with 17.8 days for those with ecthyma gangrenosum (P less than 0.05 by the Wilcoxon test) . These observations show that P . aeruginosa skin infections can develop in the absence of bacteremia in immunocompromised children.

Rev Soc Bras Med Trop, 1991 Jul-Sep, 24(3), 163 - 8
Bacteriological evaluation of wounds in seriously burned hospitalized patients; Silva SL et al.; During the period between May and December 1988, 21 patients were studied bacteriologically at Hospital Joao XXIII's burn's unit which belongs to "Fundacao Hospitalar do Estado de Minas Gerais" in Belo Horizonte, Brazil . A qualitative and quantitative evaluation of aerobic and facultative bacteria from burn wounds was carried out by the standard filter paper disc technique, including antibiotic susceptibility . At the same time an evaluation of those bacteria isolated from the environmental unit was performed . The most common organisms recovered from wounds of patients were: Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus epidermidis . P . pseudomallei was the most frequent strain recovered from environmental specimens . In nearly all patients specimens (16 in total) from whom P . aeruginosa was isolated, the rate of CFU/cm2 of skin was above 10(2) . In nine of these, it reached 10(5), which is equivalent to 10(7) CFU/g of burned tissue.

Pathology, 1991 Jul, 23(3), 229 - 32
Pyocin typing of Pseudomonas aeruginosa isolates from children with cystic fibrosis; Richardson CJ et al.; Pyocin typing and serotyping of 433 strains of Pseudomonas aeruginosa from children with cystic fibrosis (CF) showed that pyocin type 9 was predominant, particularly in association with polyagglutinating serotype . The common pyocin groups, 1, 5 and 10, made up only 20% of these isolates in contrast to reported rates of up to 89% in other studies using non-CF strains . No strains of pyocin type 3 were found . Polyagglutinating strains made up 72% of strains from patients colonized with P . aeruginosa for more than 12 mths . Pyocin type 9 was associated with 93% of polyagglutinating strains . The parallel between pyocin type 9 and polyagglutinating serotype suggests that these may both be characteristics acquired by P . aeruginosa colonizing patients with CF . Because of confounding between duration of colonization and exposure to cross-infection, this study does not allow definition of the role of cross-infection in determining the characteristics of these strains in most patients . In siblings, however, evidence supports a role for cross-infection either between siblings or from a common source . In 6 pairs of siblings studied, each pair had at least 1 pyocin group in common concurrently, either at entry to the study or after an interval of several months . Identical and unusual pyocin groups were recognized in samples obtained on the same day from pairs of siblings . More studies are needed to compare results of pyocin typing with methods such as genome fingerprinting to characterize these strains and determine whether the observed distribution of pyocin groups in CF isolates is related to cross-infection or whether the combination of pyocin type 9 with polyagglutinating serotype is a characteristic of CF strains.

Prikl Biokhim Mikrobiol, 1991 Jul-Aug, 27(4), 523 - 8
{Adsorption immobilization of alkaline lipase}; Sof'ina EIa et al.; A polyamide with the covalently coupled phosphatidyl ethanolamine was used for affinity adsorption of an alkaline lipase from Pseudomonas aeruginosa . The immobilization resulted in increase of the enzyme specific activity . Some properties of native and adsorbed enzyme were compared . The temperature optima, heat and pH stability, KM and Vmax values were determined for both native and immobilized enzymes.

Am J Respir Cell Mol Biol, 1991 Jul, 5(1), 51 - 5
Structure, secretion, and bacterial specificity of an endogenous lectin from cystic fibrosis lung; Ceri H et al.; Endogenous heparin-binding lectin purified from postmortem lung samples of two cystic fibrosis (CF) patients was compared to lectin derived from normal tissue with respect to structure, carbohydrate specificity, interaction with alginate derived from CF isolates of Pseudomonas aeruginosa, and secretion within the lung . Lectin was purified from extracts of lung tissue by gel filtration on Sepharose CL-2B followed by affinity chromatography on heparin-Sepharose . Lectin purified from either CF lung or control tissue ran as two peptides of approximately 16,000 and 13,000 molecular weight on electrophoresis in sodium dodecyl sulfate . The lectins displayed similar carbohydrate specificity and interacted in much the same way with bacterial alginate . An increase in lectin secretion was seen in CF lungs affecting the bronchial epithelial cells and the mucosal glands . The data suggest that the major changes seen in endogenous heparin-binding lectin in CF are related to the quantity and distribution of lectin secretion.

J Hosp Infect, 1991 Jul, 18(3), 191 - 200
The effect of disinfectants on perforated gloves; Mehtar S et al.; Three types of gloves, 'Biogel', 'Regent Dispo Surgical' gloves and Ansell gammex were perforated, and contaminated with Escherichia coli or Pseudomonas aeruginosa as test organisms applied either to the hand or the glove surface . The glove surface was decontaminated with alcoholic chlorhexidine ('Hibisol'), methylated spirit, or soap and water . The experiments were performed in triplicate on three separate days . The experiments were designed to study the ability of the three disinfection methods to reduce the bacterial count of 10(6) colony forming units (cfu) ml-1 (applied to perforated gloves or hands) sufficiently to permit the re-use of such gloves for non-sterile ward procedures . The best method of disinfection was using alcoholic chlorhexidine which not only reduced glove surface carriage but also reduced transfer of bacteria to the hands through the perforation in the gloves . Soap and water was the least effective . Escherichia coli was more easily removed than P . aeruginosa . We recommend that non-sterile ward procedures may be carried out even after gloves have been perforated provided alcoholic chlorhexidine is used between each procedure to reduce cross-infection between patients.

J Bacteriol, 1991 Jul, 173(13), 4212 - 9
Hydrocarbon assimilation and biosurfactant production in Pseudomonas aeruginosa mutants; Koch AK et al.; We isolated transposon Tn5-GM-induced mutants of Pseudomonas aeruginosa PG201 that were unable to grow in minimal media containing hexadecane as a carbon source . Some of these mutants lacked extracellular rhamnolipids, as shown by measuring the surface and interfacial tensions of the cell culture supernatants . Furthermore, the concentrated culture media of the mutant strains were tested for the presence of rhamnolipids by thin-layer chromatography and for rhamnolipid activities, including hemolysis and growth inhibition of Bacillus subtilis . Mutant 65E12 was unable to produce extracellular rhamnolipids under any of the conditions tested, lacked the capacity to take up 14C-labeled hexadecane, and did not grow in media containing individual alkanes with chain lengths ranging from C12 to C19 . However, growth on these alkanes and uptake of {14C}hexadecane were restored when small amounts of purified rhamnolipids were added to the cultures . Mutant 59C7 was unable to grow in media containing hexadecane, nor was it able to take up {14C}hexadecane . The addition of small amounts of rhamnolipids restored growth on alkanes and {14C}hexadecane uptake . In glucose-containing media, however, mutant 59C7 produced rhamnolipids at levels about twice as high as those of the wild-type strain . These results show that rhamnolipids play a major role in hexadecane uptake and utilization by P . aeruginosa.

Infect Immun, 1991 Jul, 59(7), 2351 - 8
Immunostimulatory, but not antiendotoxin, activity of lipid X is due to small amounts of contaminating N,O-acylated disaccharide-1-phosphate: in vitro and in vivo reevaluation of the biological activity of synthetic lipid X; Lam C et al.; Lipid X, a precursor in the biosynthesis of lipid A, has been claimed to possess most of the immunostimulatory activity but none of the toxicity of endotoxin . However, recent work shows that synthetic lipid X can be contaminated with small amounts of N,O-acylated disaccharide-1-phosphate (H . Aschauer, A . Grob, J . Hildebrandt, E . Schuetze, and P . Steutz, J . Biol . Chem . 265:9159-9164, 1990) . Because the impurities themselves exhibit immunostimulatory properties, it was necessary to establish whether chemically pure synthetic lipid X exhibits any of the endotoxinlike biological activities previously attributed to the native compound extracted from the Escherichia coli MN7 mutant . In the present study, two batches of synthetic lipid X were used: batch A contained the contaminating disaccharide, and batch B was pure lipid X . Batch A, previously believed to be pure on the basis of spectroscopic and microanalysis data, induced murine peritoneal macrophages to secrete tumor necrosis factor, interleukin-1, and prostaglandin E2 at a minimal dose of 10 micrograms/ml in vitro . Batch B, further purified by Sephadex LH 20 chromatography, was found virtually inactive in these in vitro assays . Furthermore, batch A was pyrogenic in rabbits at a dose of 0.05 mg/kg, whereas batch B was not pyrogenic at doses of up to greater than or equal to 2 mg/kg . However, both batches were equally tolerated by galactosamine-loaded mice at doses of up to 100 mg/kg . Surprisingly, while only batch A protected neutropenic mice against lethal infection with Pseudomonas aeruginosa (50% effective dose, 12.4 mg/kg), both batches were equally protective against infection with herpes simplex virus type 1 in mice and guinea pigs, even when lipid X was administered therapeutically . Interestingly, both batches of lipid X blocked endotoxin-induced expression of monocyte procoagulant activity and priming of human neutrophils for superoxide anion release . Similarly, both batches protected galactosamine-sensitized mice from otherwise lethal endotoxemia when administered prophylactically or simultaneously with the lipopolysaccharide challenge . Thus, our findings suggest that chemically pure lipid X (batch B) is devoid of the immunostimulatory properties of lipid A or endotoxin . Rather, it behaves as a competitive inhibitor of lipopolysaccharide . We conclude, therefore, that previous studies which attributed immunostimulatory activities to any batch of synthetic lipid X should be interpreted with caution.

Nucleic Acids Res, 1991 Jun 25, 19(12), 3199 - 206
The impact of two-dimensional pulsed-field gel electrophoresis techniques for the consistent and complete mapping of bacterial genomes: refined physical map of Pseudomonas aeruginosa PAO; Romling U et al.; The SpeI/DpnI map of the 5.9 Mb Pseudomonas aeruginosa PAO (DSM 1707) genome was refined by two-dimensional (2D) pulsed-field gel electrophoresis techniques (PFGE) which allow the complete and consistent physical mapping of any bacterial genome of interest . Single restriction digests were repetitively separated by PFGE employing different pulse times and ramps in order to detect all bands with optimum resolution . Fragment order was evaluated from the pattern of 2D PFGE gels: 1 . Partial-complete digestion . A partial restriction digest was separated in the first dimension, redigested to completion, and subsequently perpendicularly resolved in the second dimension . 2D-gel comparisons of the ethidium bromide stain of all fragments and of the autoradiogram of end-labeled partial digestion fragments was nearly sufficient for the construction of the macrorestriction map . 2 . Reciprocal gels . A complete restriction digest with enzyme A was run in the first dimension, redigested with enzyme B, and separated in the second orthogonal direction . The order of restriction digests was reverse on the second gel . In case of two rare-cutters, fragments were visualized by ethidium bromide staining or hybridization with genomic DNA . If a frequent and a rare cutter were employed, linking fragments were identified by end-labeling of the first digest . 3 . A few small fragments were isolated by preparative PFGE and used as a probe for Southern analysis.--38 SpeI and 15 DpnI fragments were positioned on the map . The zero point was relocated to the 'origin of replication' . The anonymous mapping techniques described herein are unbiased by repetitive DNA, unclonable genomic regions, unfavourable location of restriction sites, or cloning artifacts as frequently encountered in other top-down or bottom-up approaches.

Eur J Biochem, 1991 Jun 15, 198(3), 697 - 704
Structural characterization of the lipid A component of Pseudomonas aeruginosa wild-type and rough mutant lipopolysaccharides; Kulshin VA et al.; The structure of the lipid A component of lipopolysaccharides isolated from two wild-type strains (Fisher 2 and 7) and one rough mutant (PAC 605) of Pseudomonas aeruginosa was investigated using chemical analysis, methylation analysis, combined gas-liquid chromatography/mass spectrometry, laser-desorption mass spectrometry and NMR spectroscopy . The lipid A backbone was found to consist of a pyranosidic beta 1,6-linked D-glucosamine disaccharide {beta-D-GlcpN-(1----6)-D-GlcpN}, phosphorylated in positions 4' and 1 . Position 6' of the beta-D-GlcpN-(1----6)-D-GlcpN disaccharide was identified as the attachment site of the core oligosaccharide and the hydroxyl group at C-4 was not substituted . Lipid A of the three P . aeruginosa strains expressed heterogeneity with regard to the degree of acylation: a hexaacyl as well as a pentaacyl component were structurally characterized . The hexaacyl lipid A contains two amide-bound 3-O-acylated (R)-3-hydroxydodecanoic acid groups {12:0(3-OH)} at positions 2 and 2' of the GlcN dissacharide and two ester-bound (R)-3-hydroxydecanoic acid groups {10:0(3-OH)} at positions 3 and 3' . The pentaacyl species, which represents the major lipid A component, lacks one 10:0(3-OH) residue, the hydroxyl group in position 3 of the reducing GlcN residue being free . In both hexa- and pentaacyl lipid A the 3-hydroxyl group of the two amide-linked 12:0(3-OH) residues are acylated by either dodecanoic (12:0) or (S)-2-hydroxydodecanoic acid {12:0(2-OH)}, the lipid A species with two 12:0(2-OH) residues, however, being absent . The presence of only five acyl residues in the major lipid A fraction may account for the low endotoxic activity observed with P . aeruginosa lipopolysaccharide.

Gene, 1991 Jun 15, 102(1), 7 - 12
Characterization of the blaCARB-3 gene encoding the carbenicillinase-3 beta-lactamase of Pseudomonas aeruginosa; Lachapelle J et al.; We have isolated the blaCARB-3 structural gene encoding the CARB-3 carbenicillinase of Pseudomonas aeruginosa strain Cilote, tested the specificity of blaCARB-3 DNA probes and determined the nucleotide sequence of blaCARB-3 . Three restriction fragment probes internal or delimiting the blaCARB-3 structural gene were hybridized with purified plasmid DNA coding for 18 other beta-lactamases (Blas) . Under high-stringency conditions, only blaPSE-1, blaPSE-4, and blaCARB-4 sequences cross-hybridized with blaCARB-3 . Sequencing of blaCARB-3 identified the structural gene which encodes a polypeptide product of 268 amino acids with a calculated estimated Mr of 29,246 for the mature form of the protein . Homology studies and computer analysis of primary structures confirmed that CARB-3 is a class-A Bla . The CARB-3 carbenicillinase differs from PSE-4 at two positions: Phe (PSE-4) instead of Leu188 (CARB-3), and Glu (PSE-4) instead of Ala266 (CARB-3), which changes the isoelectric value from (PSE-4) 5.4 to 5.75 (CARB-3) . The possible effects of these two mutations were examined by comparisons on the 2 A crystal structure of the Staphylococcus aureus penicillinase, and they were shown to be silent substitutions causing no changes in the phenotype . The nucleic acid hybridization studies and sequence data confirmed that carbenicillinase-encoding bla genes are closely related and that blaCARB-3 is a variant of blaPSE-4.

Hybridoma, 1991 Jun, 10(3), 401 - 9
Optimization of growth and secretion of human monoclonal antibodies by hybridomas cultured in serum-free media; Lang AB et al.; To facilitate the production and purification of human monoclonal antibodies, we evaluated the ability of human hybridomas to adapt to chemically defined-serum free media . From a panel of human hybridomas secreting antibody against serotype specific lipopolysaccharide determinants of gram-negative bacteria, the growth and secretion properties of the two hybridomas producing antibodies against two strains of Pseudomonas aeruginosa, 4-8KH15 and 4-10KH139, were analysed . Both clones did not grow in protein-free medium . However, it was possible to adapt them to serum-free media consisting of a basal medium supplemented with insulin, transferrin, ethanolamine, and selenite . Antibody secretion rates were equal (4-8KH15: 26-31 micrograms IgM/10(6) cells/day) or higher (4-10KH139: 58-90 micrograms IgM/10(6) cells/day) in serum-free media as compared to conventional serum-supplemented medium . Our studies suggest that adaptation of the described hybridomas to selected serum-free media results in an antibody production which is very high as compared with reports in comparable systems . The establishment of these conditions will significantly facilitate the production of large amounts of human monoclonal antibodies which is a prerequisite for a therapeutical application.

FEBS Lett, 1991 Jun 3, 283(2), 177 - 9
Cloning of the protein D2 gene of Pseudomonas aeruginosa and its functional expression in the imipenem-resistant host; Yoneyama H et al.; Protein D2 forms the water-filled pore across the outer membrane of Pseudomonas aeruginosa and allows the penetration of imipenem . We cloned the protein D2 gene by the antibody screening technique . When the imipenem-resistant mutant lacking protein D2 harbored the plasmid with the cloned D2 gene, the mutant overproduced protein D2 in the outer membrane . These transformants exhibited fully-restored imipenem susceptibility . The results prove unequivocally that protein D2 forms the imipenem-permeable pore in the P . aeruginosa outer membrane.

Pediatrics, 1991 Jun, 87(6), 897 - 9
Role of flexible bronchoscopy and bronchoalveolar lavage in the diagnosis of pediatric acquired immunodeficiency syndrome-related pulmonary disease; Birriel JA Jr et al.; Flexible fiberoptic bronchoscopy with bronchoalveolar lavage was performed in 16 pediatric patients with the acquired immunodeficiency syndrome (AIDS) and deterioration in pulmonary function suggestive of opportunistic infection . In 62% of the patients Pneumocystis carinii was identified . Culture results showed a pure growth of Pseudomonas aeruginosa for one patient in addition to the Pneumocystis carinii . Bronchoscopy with lavage was well tolerated, with few complications even among patients with significant tachypnea and hypoxia . Because of its relative safety and effectiveness, this procedure should be considered the first invasive measurement used for evaluation of parenchymal lung disease in this population of patients.

J Antimicrob Chemother, 1991 Jun, 27(6), 801 - 8
Synergy with cefsulodin or piperacillin and three aminoglycosides or aztreonam against aminoglycoside resistant strains of Pseudomonas aeruginosa; Baltch AL et al.; Fifty-one strains of Pseudomonas aeruginosa, with resistance to one or more amino-glycosides, were tested for synergy with cefsulodin or piperacillin plus amikacin, tobramycin, gentamicin or aztreonam by the agar dilution technique . Cefsulodin plus any one of the three aminoglycosides regardless of the degree of resistance to the aminoglycoside was synergistic against P . aeruginosa for two thirds of the isolates . In contrast, synergy rates with piperacillin were much less uniform . The highest rate of synergy with piperacillin (90.0%) was observed with gentamicin for the gentamicin resistant strains . The lowest rate of synergy was observed with piperacillin plus amikacin (32.2%) for isolates with moderate resistance to amikacin . Synergy for strains with moderate resistance to amikacin was observed more commonly with cefsulodin than with piperacillin . Synergy for strains with a known mechanism of resistance to amikacin was more common with cefsulodin regardless of the mechanism of resistance . Cefsulodin or piperacillin in combination with aztreonam was rarely synergistic (less than 12%).

Antimicrob Agents Chemother, 1991 Jun, 35(6), 1258 - 60
Use of slime dispersants to promote antibiotic penetration through the extracellular polysaccharide of mucoid Pseudomonas aeruginosa; Gordon CA et al.; Agents with the potential to reduce Pseudomonas aeruginosa alginate viscosity (slime dispersants) were shown to promote the diffusion of antipseudomonal antibiotics through alginate but were more effective in facilitating the diffusion of gentamicin than that of ceftazidime . EDTA increased the diffusion rates of these antibiotics by factors of 4.0 and 1.5, respectively, although sodium chloride significantly reduced viscosity and enhanced gentamicin diffusion.

Antimicrob Agents Chemother, 1991 Jun, 35(6), 1245 - 6
In vitro and in vivo studies of ME1228, a new parenteral cephalosporin with potent activity against Pseudomonas aeruginosa; Miyazaki S et al.; The therapeutic effect of ME1228, a new parenteral cephalosporin, was compared with that of broad-spectrum cephems in normal and neutropenic mice infected with various species of bacteria . The results showed that ME1228 was more active than were the other cephems against infections with various pathogens.

J Chemother, 1991 Jun, 3(3), 147 - 51
Enoxacin therapy for experimental pseudomonas keratitis; Esposito S et al.; Pseudomonas keratitis is difficult to treat and aminoglycosides, the drugs now used for this purpose, are not always effective . New drugs are thus needed to cure gentamicin resistant pseudomonas ocular infections . Enoxacin, a new quinolone, active in vitro against Pseudomonas aeruginosa, was evaluated in experimental ulcerative keratitis produced by a gentamicin resistant isolate of Pseudomonas aeruginosa in rabbits . Our study shows that enoxacin eye drops eliminated pseudomonas infection of the cornea and achieved therapeutic levels in the aqueous humor . Supplementation with parenterally given enoxacin augmented this effect . Enoxacin did not penetrate the vitreous . Enoxacin eye drops may be evaluated for their clinical usefulness in case of keratitis caused by Gram-negative bacilli.

Can J Microbiol, 1991 Jun, 37(6), 445 - 9
The production of antibacterial tubing, sutures, and bandages by in situ precipitation of metallic salts; Farrah SR et al.; Two procedures were used to modify gauze bandages, polyester sutures, silicone tubing, and polyvinyl chloride tubing . In one procedure, the materials were first modified by in situ precipitation of metallic hydroxides and then used to adsorb silver ions . In the second procedure, the materials were soaked in sodium pyrophosphate or sodium chloride, dried, and then soaked in silver nitrate . These procedures produced materials with silver deposited on the surface of the tubing and sutures and both on the surface and within the gauze fibers . The modified materials inhibited the growth of Pseudomonas aeruginosa . Escherichia coli, and Staphylococcus aureus in vitro.

Can J Microbiol, 1991 Jun, 37(6), 411 - 8
Simultaneous degradation of acetonitrile and biphenyl by Pseudomonas aeruginosa; Nawaz MS et al.; A bacterium capable of utilizing either acetonitrile as the sole source of carbon and nitrogen or biphenyl as the sole source of carbon was isolated from soil and identified as Pseudomonas aeruginosa . The bacterium also utilized other nitriles, amides, and polychlorinated biphenyls (PCBs) as growth substrates . Acetonitrile- or biphenyl-grown cells oxidized these substrates without a lag . In studies with {14C}acetonitrile, nearly 74% of the carbon was recovered as 14CO2 and 8% was associated with the biomass . In studies with {14C}biphenyl, nearly 68% of the carbon was recovered as 14CO2 and nearly 6% was associated with the biomass . Although higher concentrations of acetonitrile as the sole sources of nitrogen inhibited the rates of {14C}biphenyl mineralization, lower concentrations (0.05%, w/v) gave a 77% stimulation in 14CO2 recovery . Pseudomonas aeruginosa metabolized acetonitrile to ammonia and acetic acid and biphenyl to benzoic acid . The bacterium also simultaneously utilized biphenyl as the sole carbon source and acetonitrile as the sole nitrogen source . However, biphenyl utilization increased only after the depletion of acetonitrile . Metabolites of the mixed substrate were ammonia and benzoic acid, which completely disappeared in the later stages of incubation . Nitrile hydratase and amidase were responsible for the transformation of acetonitrile to acetic acid and ammonia.

Nihon Kyobu Shikkan Gakkai Zasshi, 1991 Jun, 29(6), 703 - 9
{Serum sensitivity of Pseudomonas aeruginosa isolated from sputum as a virulence factor in the lower respiratory tract}; Sonoda F et al.; To elucidate the clinical significance of serum-sensitivity of respiratory pathogenic Pseudomonas aeruginosa (P . aeruginosa) strains, we examined serum-sensitivity of P . aeruginosa isolated from 16 patients with lower respiratory tract infections and clinical backgrounds of these patients . We also evaluated the virulence of four serum-resistant and four serum-sensitive P . aeruginosa strains in murine pneumonia model induced by intratracheal challenge, and the silver-stained profiles of purified lipopolysaccharide (LPS) from these strains . Serum-sensitive strains were isolated only from patients with chronic bronchitis, bronchiectasis, and diffuse panbronchiolitis colonized with P . aeruginosa, and rarely caused pneumonias, while serum-resistant strains caused pneumonias in some cases . Intratracheal challenge of mice with 5 x 10(7) cfu per mouse of a serum resistant strain caused fatal hemorrhagic pneumonia with bacteremia . In contrast, the same dose of a serum-sensitive strain provided non-fatal pneumonia without bacteremia . LD50 of serum-sensitive strains in a murine model of P . aeruginosa pneumonia were at least 2-10 times higher than those of serum-resistant strain . The LPS profiles of two serum-resistant strains and one serum-sensitive strain showed ladder-like patterns . The similar analysis demonstrated that one serum-sensitive strain was lack of ladder-like patterns . These data support that serum-sensitive P . aeruginosa strains are less virulent than serum-resistant P . aeruginosa strains in the lower respiratory tract, and serum sensitivity of P . aeruginosa strains is determined by the structure of the O-side chain of LPS; either lack of the O-side chain or the presence of sparse O-side chain.

Zh Mikrobiol Epidemiol Immunobiol, 1991 Jun, (6), 22 - 5
{The optimization of the batch cultivation process for Pseudomonas aeruginosa to produce exotoxin A}; Kuznetsova TN et al.; The experimental study of conditions for the optimization of the batch cultivation of P . aeruginosa has been made . As revealed in this study the aim of this cultivation can be achieved by using exponentially growing culture in a dose of 1.10(9) cells/ml as seed material and by ensuring the conditions of rational air supply during the main cultivation process.

Appl Environ Microbiol, 1991 Jun, 57(6), 1740 - 5
Isolation and characterization of a lipolytic bacterium capable of growing in a low-water-content oil-water emulsion; Shabtai Y; A unique lipolytic bacterium was isolated in a selective growth system consisting of 99% triglycerides and a 1% water phase . The bacterium, termed Pseudomonas aeruginosa YS-7, was able to grow in an environment of low water content and could also survive amphipathic, osmotic, and matrical water stress in a triglyceride-rich culture . The isolated strain was identified as P . aeruginosa on the basis of standard physiological, biochemical, and serological assays . The strain is a gram-negative motile rod, aerobic, pigment forming, and capable of growing at 42 degrees C . It is highly tolerant of high concentrations of the cationic detergent cetyltrimethylammonium bromide and of the fatty acid salts derived from bacterial hydrolysis of the oil . Growth of the bacterium in a pure culture in a 99% triglyceride medium lasted until most of the water was evaporated or consumed . Growth was accompanied by triglyceride hydrolysis, which continued to occur even after growth saturation until the water was totally depleted . No loss of viability was observed when the culture was maintained under water-depleted conditions for an additional 40 h . A second cycle of bacterial growth and triglyceride hydrolysis was immediately initiated upon the addition of 1% (vol/vol) water to the culture . Lipase activity was stable regardless of changes in culture conditions . The isolated strain is uniquely resistant to severe water stress in a triglyceride-rich medium or under cold acetone precipitation compared with 12 other microbial strains, including bacteria and yeasts . Among these 12, only the lipolytic strains grew in the 99% triglyceride medium, but they reached a cell mass fourfold smaller than that of P . aeruginosa YS-7.(ABSTRACT TRUNCATED AT 250 WORDS)

J Clin Microbiol, 1991 Jun, 29(6), 1265 - 7
Nosocomial acquisition of Pseudomonas aeruginosa by cystic fibrosis patients; Tummler B et al.; During a 4-year period, at least 12 of 40 patients with cystic fibrosis (CF) who were newly colonized with Pseudomonas aeruginosa had acquired it at CF recreation camps, clinics, or rehabilitation centers . After introduction of hygienic precautions at the CF clinic, only a single episode of nosocomial transmission of P . aeruginosa was detected at the CF ward during the subsequent 2 years.

J Med Microbiol, 1991 Jun, 34(6), 349 - 53
Effect of plastic catheter material on bacterial adherence and viability; Lopez-Lopez G et al.; The kinetics of adherence of single isolates of Staphylococcus aureus, S . epidermidis, Pseudomonas aeruginosa and Escherichia coli to catheters made of polyvinyl chloride (PVC), Teflon, siliconised latex, polyurethane and Vialon was evaluated by a radiometric assay . Radiolabelled bacteria (10(8) cfu/ml) were incubated in vials containing 1-cm lengths of catheter for up to 3 days . The peak of maximal adherence to each biomaterial was reached after 24 h for P . aeruginosa and after 72 h for the other strains . Bacterial adherence to PVC and siliconised latex was significantly higher (2-6 times; p less than 0.05) than to the other biomaterials for all the strains . The lowest values of adherence were observed with polyurethane and Vialon for the staphylococci but with Teflon for E . coli and P . aeruginosa . Bacterial viability and growth was evaluated in eluates obtained from incubation of segments of each catheter in buffer for 24 h . None of the eluates affected the viability of the staphylococci . However, all of them, significantly increased the growth of E . coli and P . aeruginosa with the exception of the eluate from siliconised latex, in which the inoculum count was reduced to an undetectable level for E . coli . We conclude that bacterial adherence to catheters may depend in part on the nature of the biomaterial and that certain substances eluted from the catheters may affect the viability and growth of different micro-organisms.

Invest Ophthalmol Vis Sci, 1991 Jun, 32(7), 2096 - 104
Characterization of pseudomonal adherence to unwounded cornea; Singh A et al.; This study examined binding of Pseudomonas aeruginosa to unwounded postnatal day (P) 5 immature mouse cornea . To determine whether the receptor molecule was protein or lipid in nature, the eyes were incubated in vitro with trypsin or lipase before bacteria were applied . Trypsin significantly increased bacterial binding, whereas lipase had no effect . To determine if enhanced binding after trypsin indicated exposure of a lipid or a protein receptor, the eyes were treated sequentially with trypsin, then lipase . Subsequent binding did not differ significantly from trypsin alone, indicating that the exposed receptor was not a lipid . Incubation of the P 5 eye with neuraminidase to remove sialylated residues also significantly enhanced binding at all times, and premixing of the inoculum with the enzyme before adherence testing increased binding at 15 and 30 min . The effects of a monosialoganglioside (GM1) and gangliotetraosylceramide (asialo GM1) were also examined . Incubation of eyes with GM1 or asialo GM1 produced no significant inhibition of bacterial binding, but premixing of the bacterial inoculum with GM1 or asialo GM1 before corneal application transiently decreased adherence . Fibronectin (FN) treatment of the P 5 eye, premixing FN with the bacterial inoculum before its ocular application, or similar treatment with N-acetylneuraminic acid (NANA) transiently inhibited binding . These data demonstrate that pseudomonal binding to the unwounded eye is not lipase sensitive and is enhanced by trypsin treatment which exposes a lipase insensitive receptor and by neuraminidase which removes sialylated residues . It is not inhibited by pretreatment of the eye with either GM1 or asialo GM1 and is transiently inhibited by pretreatment of the eye or the inoculum with NANA or FN.

APMIS, 1991 Jun, 99(6), 492 - 8
Genome fingerprinting as a typing method used on polyagglutinable Pseudomonas aeruginosa isolates from cystic fibrosis patients; Ojeniyi B et al.; Phenotypical changes occur in the surface of Pseudomonas aeruginosa during the chronic lung infection of cystic fibrosis patients . It is difficult with the classical typing methods, such as serotyping, phage typing and pyocin typing, to decide if a patient has been colonized with a new strain or whether it is the same strain which has reappeared, for instance after chemotherapy in the lungs . This investigation was carried out to evaluate genome fingerprinting as a typing method and to see how it correlated with classical methods and with DNA probe typing . Forty Pseudomonas aeruginosa isolates, 34 polyagglutinable and six monoagglutinable, from 14 cystic fibrosis patients were analysed using genome fingerprinting . The bacterial chromosomes were digested with the restriction endonucleases Dra 1 and Xbal, and separated by field inversion gel electrophoresis . The results were compared with those of a previous work (Ojeniyi et al . 1990) concerning typing with a DNA probe, serotyping using both polyclonal and monoclonal sera, phage typing, pyocin typing and reverse phage typing . The results of genome fingerprinting and DNA probe typing showed the best correlation, followed by pyocin typing . The correlation between the results of genome typing and the other typing methods was low . The discriminatory effect of genome fingerprinting was higher than that of DNA probe typing, and genome fingerprinting was found to be the best single method for epidemiological investigations of polyagglutinable isolates from cystic fibrosis patients.

J Bacteriol, 1991 Jun, 173(12), 3763 - 9
Activation of the trpBA promoter of Pseudomonas aeruginosa by TrpI protein in vitro; Gao JG et al.; We have developed an in vitro transcription system in which purified TrpI protein and indoleglycerol phosphate (InGP) activate transcription initiation at the trpBA promoter (trpPB) and repress initiation at the trpI promoter (trpPI) of Pseudomonas aeruginosa . The phenotypes resulting from mutations in the -10 region of both promoters indicate that the -10 region consensus sequence in P . aeruginosa is probably the same as that in Escherichia coli . Furthermore, in the absence of TrpI and InGP, the activities of the two promoters are inversely correlated: down mutations in trpPI lead to increased activity of trpPB, and up mutations in trpPB cause a decrease in trpPI activity . These results are a consequence of the fact that the two promoters overlap, so that RNA polymerase cannot form open complexes with both promoters simultaneously . Thus, in theory, by preventing RNA polymerase from binding at trpPI, TrpI protein could indirectly activate trpPB . However, oligonucleotide-induced mutations that completely inactivate trpPI do not relieve the requirement for TrpI and InGP to activate trpPB . Therefore, activation of trpPB is mediated by a direct effect of TrpI on transcription initiation at trpPB . In addition, the oligonucleotide-induced mutations in trpPI alter site II, the weaker of two TrpI binding sites identified in DNase I and hydroxyl radical footprinting studies (M . Chang and I . P . Crawford, Nucleic Acids Res . 18:979-988, 1990) . Since these mutations prevent full activation of trpPB, we conclude that specific base pairs in site II are required for activation.

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