SADJ, 1999 Oct, 54(10), 464 - 9 The effect of elastomeric impression materials on the growth of micro-organisms; Tuit CM et al.; The influence of elastomeric impression materials on the growth of micro-organisms was examined in vitro . Bacillus subtilis was inoculated into broth containing impression materials and incubated at 37 degrees C for 72 hours . Express STD Putty, President Putty and Jet-Light Body, Low and Very High Viscosity Permagum and Provil L stimulated growth whereas Impregum-F and Express Light Body inhibited growth . The influence of Impregum-F and Express Light Body on oral micro-organisms was investigated further . Broth extracts were prepared by soaking these materials in Todd Hewitt broth for either 5 or 10 minutes . Thereafter, the extracts were inoculated with oral strains of Staphylococcus aureus, Streptococcus mutans and Candida albicans, incubated at 37 degrees C for 72 hours and plated on blood and Sabourauds agar to test for the presence of viable micro-organisms . The 10-minute broth extracts killed all the test isolates which suggests that impressions taken with Impregum-F and Express Light Body may not require disinfecting. Heart, 2000 Jul, 84(1), 25 - 30 Infective endocarditis: clinical spectrum, presentation and outcome . An analysis of 212 cases 1980-1995; Netzer RO et al.; OBJECTIVE: To evaluate recent changes in the spectrum and clinical presentation of infective endocarditis and to determine predictors of outcome . DESIGN: A retrospective case study . METHODS: Demographic, clinical, and echocardiographic characteristics were examined in 212 patients who fulfilled the Duke criteria for infective endocarditis between January 1980 and December 1995 to assess changes in clinical presentation and survival . RESULTS: Clinical presentation and course did not change significantly during the study period despite the concurrent introduction of new diagnostic tools (for example, transoesophageal echocardiography) . In-hospital mortality was 15% and remained unchanged . Neurological symptoms on admission, arthralgia, and weight loss were all independent risk factors for adverse outcome (odds ratios 26.1, 6.2, and 4.2, respectively) . Age, prosthetic valve disease, previous antibiotic treatment, renal insufficiency, surgical treatment, and the type of valve involved were not predictive of mortality . In contrast to all other major reports, Streptococcus viridans was the most common causative organism in intravenous drug users (52%) . CONCLUSIONS: Despite the introduction of new diagnostic tools, the course of infective endocarditis has remained unchanged over a period of 16 years . Evidence of early dissemination of the disease to other sites was associated with adverse outcome . Even in elderly patients, early aggressive treatment seems to be effective. Arch Mal Coeur Vaiss, 2000 May, 93(5), 631 - 4 {Osler endocarditis of a ventricular septal defect in a 21-month old child}; Legendre A et al.; The authors report a case of streptococcus mitis endocarditis of a ventricular septal defect in a 21 months old girl admitted for necrotic purpura of the lower limbs and a history of general ill health and pyrexia for two months . The severity of this case of endocarditis was illustrated by the importance of the vasculitis, the biological signs of infection (disseminated intravascular coagulation), and the size of the vegetation . The vegetation extended from the tricuspid valve as far as the pulmonary orifice which was partially obstructed, causing signs of right ventricular failure . The portal of entry was not found . Surgical ablation of the vegetation with tricuspid valvuloplasty was necessary after 48 hours of antibiotherapy . The outcome after one year's follow-up is good . The diagnosis of bacterial endocarditis must be considered even in very young children, especially those with congenital heart disease, and, in particular, ventricular septal defect. Antimicrob Agents Chemother, 2000 Jul, 44(7), 1803 - 8 IB-367, a protegrin peptide with in vitro and in vivo activities against the microflora associated with oral mucositis; Mosca DA et al.; Although the microflora associated with oral mucositis initiated by cytotoxic therapy is not well characterized, several studies suggest that reduction of the microbial load in the oral cavity has some clinical benefit . The MICs of IB-367, a synthetic protegrin analog, ranged from 0.13 to 64 microgram/ml for gram-positive bacteria (Streptococcus mitis, Streptococcus sanguis, Streptococcus salivarius, and Staphylococcus aureus) and from 0.06 to 8 microgram/ml for gram-negative species (Klebsiella, Escherichia, and Pseudomonas) . IB-367 exhibited rapid, microbicidal activity against both log- and stationary-phase cultures of methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa . At concentrations near the MICs for these two organisms (4 and 2 microgram/ml, respectively), IB-367 reduced viability by more than 3 logs in less than 16 min . Similarly, IB-367 effected a 4-log reduction of the endogenous microflora in pooled human saliva within 2 min at 250 microgram/ml, a concentration readily attained by local delivery . After nine serial transfers at 0.5x the MIC, the MIC of IB-367 for MRSA and P . aeruginosa increased only two to four times . In a phase I clinical study with healthy volunteers, IB-367 was well tolerated, with no detectable systemic absorption . One hour after treatment with 9 mg of IB-367, the prevalence of gram-negative bacteria and yeast was reduced, and the density of the predominant gram-positive oral flora was decreased 1,000 times . IB-367's properties (speed of killing, breadth of spectrum, and lack of resistance) make the compound a strong candidate for the prophylaxis of oral mucositis . Phase II clinical trials with IB-367 are under way for this indication in immunocompromised subjects. Infect Immun, 2000 Jul, 68(7), 4180 - 8 The putative proteinase maturation protein A of Streptococcus pneumoniae is a conserved surface protein with potential to elicit protective immune responses; Overweg K et al.; Surface-exposed proteins often play an important role in the interaction between pathogenic bacteria and their host . We isolated a pool of hydrophobic, surface-associated proteins of Streptococcus pneumoniae . The opsonophagocytic activity of hyperimmune serum raised against this protein fraction was high and species specific . Moreover, the opsonophagocytic activity was independent of the capsular type and chromosomal genotype of the pneumococcus . Since the opsonophagocytic activity is presumed to correlate with in vivo protection, these data indicate that the protein fraction has the potential to elicit species-specific immune protection with cross-protection against various pneumococcal strains . Individual proteins in the extract were purified by two-dimensional gel electrophoresis . Antibodies raised against three distinct proteins contributed to the opsonophagocytic activity of the serum . The proteins were identified by mass spectrometry and N-terminal amino acid sequencing . Two proteins were the previously characterized pneumococcal surface protein A and oligopeptide-binding lipoprotein AmiA . The third protein was the recently identified putative proteinase maturation protein A (PpmA), which showed homology to members of the family of peptidyl-prolyl cis/trans isomerases . Immunoelectron microscopy demonstrated that PpmA was associated with the pneumococcal surface . In addition, PpmA was shown to elicit species-specific opsonophagocytic antibodies that were cross-reactive with various pneumococcal strains . This antibody cross-reactivity was in line with the limited sequence variation of ppmA . The importance of PpmA in pneumococcal pathogenesis was demonstrated in a mouse pneumonia model . Pneumococcal ppmA-deficient mutants showed reduced virulence . The properties of PpmA reported here indicate its potential for inclusion in multicomponent protein vaccines. Infect Immun, 2000 Jul, 68(7), 3949 - 55 Selection of recombinant antibodies specific for pathogenic Streptococcus suis by subtractive phage display; de Greeff A et al.; A semisynthetic antibody phage display library was used to select recombinant antibodies directed against surface components of a pathogenic strain of Streptococcus suis serotype 2 and against extracellular factor (EF), a protein known to be exclusively associated with pathogenic S . suis serotype 2 strains . Three distinct monoclonal phage antibodies directed against conformational epitopes of surface protein components of S . suis were selected . In addition, three different monoclonal phage antibodies were isolated that recognized EF . To isolate antibody fragments that recognize epitopes specific for a pathogenic S . suis serotype 2 strain, compared to a nonpathogenic serotype 2 strain, we applied a subtractive selection procedure . With this procedure, only one distinct phage antibody was found, and it was shown to be directed against EF . This demonstrates the selectivity of the applied procedure and confirms that EF is indeed differentially expressed by pathogenic and nonpathogenic strains . It also shows that EF is a very dominant antigen in phage antibody selections. Curr Microbiol, 2000 Aug, 41(2), 106 - 8 Variation in sic gene encoding complement-inhibiting protein of Streptococcus pyogenes serotype M1 isolates in Japan; Murase T et al.; DNA sequencing of the gene encoding a complement-inhibiting protein of Streptococcus pyogenes (streptococcal inhibitor of complement, Sic) was carried out on 49 strains of S . pyogenes serotype M1 . Those strains were obtained from patients and asymptomatic carriers in Japan from 1969 to 1997 and had various pulsed-field gel electrophoresis (PFGE) patterns . Four identical polymorphic sites were found in the strains with the same PFGE pattern (Ia), but not in those giving the pattern IIa . The other identical sites were found in the strains with the PFGE pattern IIa, but not in those with the pattern Ia . These observations suggest that each of PFGE patterns was restricted to a set of variation in the sic gene. J S Afr Vet Assoc, 1999 Dec, 70(4), 156 - 7 Teat lesions and their relationship to intramammary infections on small-scale dairy farms in Kiambu district in Kenya; Mulei CM; Mammary gland quarters of 139 lactating dairy cows from small-scale dairy herds were examined visually and by palpation for teat lesions and by California mastitis test (CMT) and bacterial culture for subclinical mastitis . Teat lesions were observed in 97 teats . These included teat chaps (39.2%), teat papillomas (23.7%), teat erosions (22.7%), teat fistulae (5.1%), inverted teats (5.1%) and blocked teats (4.2%) . According to the CMT, the prevalence of subclinical mastitis was 33.4% in all the mammary gland quarters, 71.0% in quarters with teat lesions and 24.5% in quarters without teat lesions . There was a significant (P < 0.01) association between teat lesions and the prevalence of subclinical mastitis . The mammary gland quarters with teat lesions were 7.2 times more likely to have a positive CMT (P < 0.01) and 5.6 times more likely to have bacterial organisms (P < 0.01) isolated from them than those without any teat lesions . The bacterial organisms most frequently isolated from the CMT-positive milk samples from both the mammary gland quarters with teat lesions and those without teat lesions were Staphylococcus aureus (50.0%), Streptococcus spp . (34.8%) and Arcanobacterium pyogenes (6.2%). J S Afr Vet Assoc, 1999 Jun, 70(2), 98 - 9 Streptococcus phocae infections associated with starvation in Cape fur seals; Henton MM et al.; Mortalities and abortions associated with starvation occurred at Cape Cross, Namibia, in Cape fur seals (Arctocephalus pusillus pusillus) . Affected seals showed lethargy and emaciation, and the most common pathological signs were those of a respiratory infection, both in adults and offspring . Streptococcus phocae was isolated from adult seals, a cub and aborted foetuses. J Biol Chem, 2000 Aug 25, 275(34), 25972 - 8 Biosynthesis of type 3 capsular polysaccharide in Streptococcus pneumoniae . Enzymatic chain release by an abortive translocation process; Forsee WT et al.; The type 3 polysaccharide synthase from Streptococcus pneumoniae catalyzes sugar transfer from UDP-Glc and UDP-glucuronic acid (GlcUA) to a polymer with the repeating disaccharide unit of {3)-beta-d-GlcUA-(1-->4)-beta-d-Glc-(1-->} . Evidence is presented that release of the polysaccharide chains from S . pneumoniae membranes is time-, temperature-, and pH-dependent and saturable with respect to specific catalytic metabolites . In these studies, the membrane-bound synthase was shown to catalyze a rapid release of enzyme-bound polysaccharide when either UDP-Glc or UDP-GlcUA alone was present in the reaction . Only a slow release of polysaccharide occurred when both UDP sugars were present or when both UDP sugars were absent . Chain size was not a specific determinant in polymer release . The release reaction was saturable with increasing concentrations of UDP-Glc or UDP-GlcUA, with respective apparent K(m) values of 880 and 0.004 micrometer . The apparent V(max) was 48-fold greater with UDP-Glc compared with UDP-GlcUA . The UDP-Glc-actuated reaction was inhibited by UDP-GlcUA with an approximate K(i) of 2 micrometer, and UDP-GlcUA-actuated release was inhibited by UDP-Glc with an approximate K(i) of 5 micrometer . In conjunction with kinetic data regarding the polymerization reaction, these data indicate that UDP-Glc and UDP-GlcUA bind to the same synthase sites in both the biosynthetic reaction and the chain release reaction and that polymer release is catalyzed when one binding site is filled and the concentration of the conjugate UDP-precursor is insufficient to fill the other binding site . The approximate energy of activation values of the biosynthetic and release reactions indicate that release of the polysaccharide occurs by an abortive translocation process . These results are the first to demonstrate a specific enzymatic mechanism for the termination and release of a polysaccharide. Arerugi, 2000 May, 49(5), 412 - 9 {Chlamydia pneumoniae infection in patients with acute bronchitis and bronchial asthma}; Oshima M et al.; In this study, a total of 60 patients with acute bronchitis, 71 patients with bronchial asthma and 20 healthy volunteers were serologically and bacteriologically analyzed to investigate whether Chlamydia pneumoniae infection is associated with the onset and the exacerbation with acute bronchitis and bronchial asthma . Antibody titers to Chlamydia pneumoniae were also measured and compared by ELISA method . The antibody-positive rate in the patients with acute bronchitis (88.4%) was significantly higher than that in the patients with bronchial asthma (73.3%) or that in the healthy volunteers (60%) . And the levels of the IgA antibody in the patients with acute bronchitis were significantly higher than those in the patients with bronchial asthma or those in the healthy volunteers . The rate of acute C . pneumoniae infection in the patients with acute bronchitis (20%) did not show significantly differences compared with that in the patients with bronchial asthma (15.5%) or that in the healthy volunteers (10%) . The cases of acute C . pneumoniae infection had both as a single etiologic agent and as a mixed infection, most often with Streptococcus pneumoniae . Therefore, we demonstrated that the acute C . pneumoniae infection may be associated with the onset and the exacerbation in acute bronchitis and bronchial asthma. J Bacteriol, 2000 Jun, 182(12), 3353 - 60 Hyperrecombination in Streptococcus pneumoniae depends on an atypical mutY homologue; Samrakandi MM et al.; The unusual behavior of the mutation ami36, which generates hyperrecombination in two point crosses, was previously attributed to a localized conversion process changing A/G mispairs into CG pairs . Although the mechanism was found to be dependent on the DNA polymerase I, the specific function responsible for this correction was still unknown . Analysis of the pneumococcal genome sequence has revealed the presence of an open reading frame homologous to the gene mutY of Escherichia coli . The gene mutY encodes an adenine glycosylase active on A/G and A/7,8-dihydro-8-oxoguanine (8-OxoG) mismatches, inducing their repair to CG and C/8-OxoG, respectively . Here we report that disrupting the pneumococcal mutY homologue abolishes the hyperrecombination induced by ami36 and leads to a mutator phenotype specifically enhancing AT-to-CG transversions . The deduced amino acid sequence of the pneumococcal MutY protein reveals the absence of four cysteines, highly conserved in the endonuclease III/MutY glycosylase family, which ligate a {4Fe-4S}(2+) cluster . The actual function of this cluster is still intriguing, inasmuch as we show that the pneumococcal gene complements a mutY strain of E . coli. Am J Respir Crit Care Med, 2000 Jun, 161(6), 2043 - 50 Differential patterns of apoptosis in resolving and nonresolving bacterial pneumonia; Kazzaz JA et al.; Infection with either Streptococcus sanguis or Streptococcus pneumoniae type 25 causes acute pneumonitis in rats . Pneumonia caused by S . sanguis resolves over the course of 8 d, whereas pneumonia caused by S . pneumoniae type 25 progresses to fibrosis . To examine the role of apoptosis in these models, we performed assays with the terminal deoxynucleotidyltransferase-uridine nucleotide end-labeling technique on tissue sections from rat lungs at various times, and quantified the results with image analysis . Apoptosis was a feature of both the acute and resolving stages of pneumonia . The pattern and extent of apoptosis were similar in both models during the acute stage, and the number of apoptotic nuclei increased in both models through 4 d after infection . Although there were differences in the cellular pattern of apoptosis after 2 d and 4 d of infection, the extent of apoptosis was the same in both models . After 8 d, major differences were observed . In the resolving model, apoptosis was limited primarily to an abscess in the base of the lung . In the nonresolving model, apoptosis was persistent . We also found that cyclin-dependent kinase-5 expression is upregulated during apoptosis induced by bacterial infection . These data indicate that the location and timing of apoptosis may determine whether pneumonia resolves or progresses to fibrosis. Laryngoscope, 2000 Jun, 110(6), 1050 - 5 Sinus tissue pharmacokinetics after oral administration of amoxicillin/clavulanic acid; Dinis PB et al.; OBJECTIVES: The in vitro synergy of the amoxicillin/clavulanic acid combination has not always translated in vivo into clinical superiority compared with amoxicillin alone . Specifically, conflicting reports have disputed the superiority of the combination in the treatment of both acute otitis media and acute sinusitis . One possible reason for this may have to do with inadequate target tissue pharmacokinetics . To explore this possibility in the sinuses, we undertook the present investigation . STUDY DESIGN: A randomized, open, single-dose, sinus tissue pharmacokinetic study with oral amoxicillin/clavulanic acid . METHODS: Twenty-three adult patients with chronic rhinosinusitis who had been selected for surgery were randomly allocated to receive a tablet of 875/125 mg amoxicillin/clavulanate 2 to 4 hours before surgery began . During the operation tissue samples were collected at specific sinonasal sites for determination of both amoxicillin and clavulanic acid concentration levels . RESULTS: Amoxicillin displayed adequate tissue levels throughout the sinuses, high enough to cover common susceptible pathogens . However, the presence of clavulanate was detected in only half of the sinonasal tissue samples . CONCLUSIONS: The kinetics of oral clavulanic acid apparently fails to provide a widespread anti-beta-lactamase activity capable of enhancing the activity of amoxicillin in all parts of the sinuses . Despite this, amoxicillin/clavulanic acid maintains a central role in the treatment of acute rhinosinusitis, because amoxicillin is still the most effective oral beta-lactam against Streptococcus pneumoniae, a particularly virulent and increasingly resistant upper respiratory tract pathogen . Also, as our data show, a concomitant anti-beta-lactamase activity can be expected to occur, although in an unpredictable fashion. Laryngoscope, 2000 Jun, 110(6), 969 - 71 Bacteriology of nontraumatic maxillary sinus mucoceles versus chronic sinusitis; Busaba NY et al.; OBJECTIVE: To compare the bacteriology of maxillary sinus mucoceles to chronic sinusitis and understand the pathogenesis of nontraumatic maxillary sinus mucoceles (NTMSM) . STUDY DESIGN: Retrospective review . METHODS: Review of intraoperative bacteriology culture results obtained in patients with NTMSM . Patients with history of facial trauma or previous paranasal sinus surgery were not included in the study . The results were compared to intraoperative cultures obtained from patients with chronic sinusitis (CS) . RESULTS: The study groups consisted of 16 patients with NTMSM (9 male and 7 female patients) and 211 patients with CS (86 male and 125 female patients) . Cultures in the NTMSM group were positive in 7 of 16 patients (44%) (four cultures had more than one isolate) . There was no growth in cultures of 9 patients (56%) . On the other hand, cultures in 176 patients with CS (83%) grew organisms (42 cultures had more than one isolate); there was no growth in 35 of 211 patients (17%) (P = .0007) . The cultures grew aerobic bacteria in 7 of 16 (44%) and 160 of 211 (76%) patients of the NTMSM and CS groups, respectively . Anaerobic bacteria were detected in cultures of 2 of 16 patients (12.5%) with NTMSM compared with 13 of 211 patients (6.2%) in the CS group (P = .286) . The most common pathogenic aerobe in the NTMSM group was alpha-hemolytic Streptococcus, while Staphylococcus aureus was the most common in the CS group . CONCLUSION: The bacteriology of maxillary sinus mucoceles is different from that of CS . The majority of patients with mucoceles have sterile intraoperative cultures . The data do not support infection as the main origin of NTMSM. J Rheumatol, 2000 Jun, 27(6), 1518 - 20 Association of HLA-DR7 with rheumatic fever in the Brazilian population; Visentainer JE et al.; OBJECTIVE: Rheumatic fever (RF) is a multisystem inflammatory disease that develops as a sequel of untreated throat infection by the group A beta-hemolytic streptococcus . As HLA antigens are known to be important in controlling immunological responsiveness, studies have investigated HLA antigen association with RF . Studies with Caucasians, Black Americans, and Indians showed associations with HLA-DR4, DR2, and DR3, respectively . One study on a Brazilian population suggested an association with HLA-DR7 and HLA-DR53 . We investigated the association between RF and antigens HLA-DR7 and DR53 in the white Brazilian population . METHODS: Thirty-five patients and 209 healthy individuals living in the northern region of the state of Parana, Brazil, were used as test and control groups, respectively . Classical statistical methods were used to compare HLA frequencies between these groups . Results . Data confirmed positive association with HLA-DR7 (46.7 vs . 25.7%; p = 0.015), but not with HLA-DR53 (54.3 vs . 44.5%; p = 0.28) . The relative risk and etiologic fractions were 2.4 and 0.27%, respectively . CONCLUSION: Positive association between HLA-DR7 specificity and RF was observed in the white Brazilian population by 2 independent studies, supporting the hypothesis of the involvement of genetic factors in susceptibility of rheumatic fever. Antibiot Khimioter, 2000, 45(4), 18 - 21 {A comparative evaluation of the pharmacokinetics of different forms of benzathine benzylpenicillin}; Belov BS et al.; Comparative randomized opened pharmacokinetic evaluation of benzathine benzylpenicillin in three dosage forms was performed . Benzathine benzylpenicillin was used as extencilline (2.4 million U or 1.2 million U, "Rhone-Poulenc Rorer", France) and as bicillin-5 (1.5 million U, "Synthesis" Russia) . 33 patients were included in investigation (23 women and 10 men aged 16-60 years) . 25 persons had verified rheumatism without blood circulation failure signs, 4--had chronic tonsillitis and 4 were healthy volunteers . Benzylpenicillin concentration was estimated by microbiology test in blood samples taken at 1, 3, 24 hours and 7, 14 and 21 days after intramuscular drug injection . After 2.4 million U extencilline injection (12 patients) its concentration, was at the inhibition level for beta-hemolytic streptococcus group A (25 ng/ml) for 3 weeks-period in 83.3 per cent of patients . After 1.2 million U extencilline injection (10 patients) or 1.5 million U bicillin-5 injection (12 patients) the above mentioned concentration was achieved on the 21st day in 30 and 0 per cent of patients respectively . Thus the treatment with benzathine benzylpenicillin at the 1.2 million U dose in the form of extencilline or bicillin-5 doesn't provide adequate antistreptococcal concentration in blood in prolonged period and is not suitable for correct rheumatism prophylaxis in adult patients. Blood, 2000 Jun 15, 95(12), 3683 - 6 Chronic graft versus host disease is associated with long-term risk for pneumococcal infections in recipients of bone marrow transplants; Kulkarni S et al.; Incidences of and risk factors for Streptococcus pneumoniae sepsis (SPS) after hematopoietic stem cell transplantation were analyzed in 1329 patients treated at a single center between 1973 and 1997 . SPS developed in 31 patients a median of 10 months after transplantation (range, 3 to 187 months) . The infection was fatal in 7 patients . The probability of SPS developing at 5 and 10 years was 4% and 6%, respectively . Age, sex, diagnosis, and graft versus host disease (GVHD) prophylaxis did not influence the development of SPS . Allogeneic transplantation (10-year probability, 7% vs 3% for nonallogeneic transplants; P =.03) and chronic GVHD (10-year probability, 14% vs 4%; P =.002) were associated with significantly higher risk for SPS . All the episodes of SPS were seen in patients who had undergone allograft or total body irradiation (TBI) (31 of 1202 vs 0 of 127; P =.07) . Eight patients were taking regular penicillin prophylaxis at the time of SPS, whereas 23 were not taking any prophylaxis . None of the 7 patients with fatal infections was taking prophylaxis for Pneumococcus . Pneumococcal bacteremia was associated with higher incidences of mortality (6 of 15 vs 1 of 16; P =.04) . We conclude that there is a significant long-term risk for pneumococcal infection in patients who have undergone allograft transplantation, especially those with chronic GVHD . Patients who have undergone autograft transplantation after TBI-containing regimens also appear to be at increased risk . These patients should receive lifelong pneumococcus prophylaxis . Consistent with increasing resistance to penicillin, penicillin prophylaxis does not universally prevent SPS, though it may protect against fatal infections . Further studies are required to determine the optimum prophylactic strategy in patients at risk . (Blood . 2000;95:3683-3686) J Bacteriol, 2000 Jul, 182(13), 3740 - 7 Role of the dpr product in oxygen tolerance in Streptococcus mutans; Yamamoto Y et al.; We have previously identified and characterized the alkyl hydroperoxide reductase of Streptococcus mutans, which consists of two components, Nox-1 and AhpC . Deletion of both nox-1 and ahpC had no effect on the sensitivity of S . mutans to cumene hydroperoxide or H(2)O(2), implying that the existence of another antioxidant system(s) independent of the Nox-1-AhpC system compensates for the deficiency . Here, a new antioxidant gene (dpr for Dps-like peroxide resistance gene) was isolated from the S . mutans chromosome by its ability to complement an ahpCF deletion mutant of Escherichia coli with a tert-butyl hydroperoxide-hypersensitive phenotype . The dpr gene complemented the defect in peroxidase activity caused by the deletion of nox-1 and ahpC in S . mutans . Under aerobic conditions, the dpr disruption mutant carrying a spectinomycin resistance gene (dpr::Spc(r) mutant) grew as well as wild-type S . mutans in liquid medium . However, the dpr::Spc(r) mutant could not form colonies on an agar plate under air . In addition, neither the dpr::Spc(r) ahpC::Em(r)::nox-1 triple mutant nor the dpr::Spc(r) sod::Em(r) double mutant was able to grow aerobically in liquid medium . The 20-kDa dpr gene product Dpr is an iron-binding protein . Synthesis of Dpr was induced by exposure of S . mutans cells to air . We propose a mechanism by which Dpr confers aerotolerance on S . mutans. J Biol Chem, 2000 Sep 1, 275(35), 26842 - 55 Do sequence repeats play an equivalent role in the choline-binding module of pneumococcal LytA amidase? Varea J, Saiz JL, Lopez-Zumel C, Monterroso B, Medrano FJ, Arrondo JL, Iloro I, Laynez J, Garcia JL, Menendez M. LytA amidase breaks down the N-acetylmuramoyl-l-alanine bonds in the peptidoglycan backbone of Streptococcus pneumoniae . Its polypeptide chain has two modules: the NH(2)-terminal module, responsible for the catalytic activity, and the COOH-terminal module, constructed by six tandem repeats of 20 or 21 amino acids (p1-p6) and a short COOH-terminal tail . The polypeptide chain must contain at least four repeats to efficiently anchor the autolysin to the choline residues of the cell wall . Nevertheless, the catalytic efficiency decreases by 90% upon deletion of the final tail . The structural implications of deleting step by step the two last (p5 and p6) repeats and the final COOH-tail and their effects on choline-amidase interactions have been examined by comparing four truncated mutants with LytA amidase by means of different techniques . Removal of this region has minor effects on secondary structure content but significantly affects the stability of native conformations . The last 11 amino acids and the p5 repeat stabilize the COOH-terminal module; each increases the module transition temperature by about 6 degrees C . Moreover, the p5 motif also seems to participate, in a choline-dependent way, in the stabilization of the NH(2)-terminal module . The effects of choline binding on the thermal stability profile of the mutant lacking the p5 repeat might reflect a cooperative pathway providing molecular communication between the choline-binding module and the NH(2)-terminal region . The three sequence motives favor the choline-amidase interaction, but the tail is an essential factor in the monomer <--> dimer self-association equilibrium of LytA and its regulation by choline . The final tail is required for preferential interaction of choline with LytA dimers and for the existence of different sets of choline-binding sites . The p6 repeat scarcely affects the amidase stability but could provide the proper three-dimensional orientation of the final tail. Lett Appl Microbiol, 2000 Jun, 30(6), 473 - 8 Anti-adhesive activity of sulphated exopolysaccharides of microalgae on attachment of red sore disease-associated bacteria and helicobacter pylori to tissue culture cells; Guzman-Murillo MA et al.; Because of the affinity of certain bacterial species for sulphated glycoconjugates exposed on the epithelial cells of susceptible hosts, we hypothesized that sulphated exopolysaccharides of microalgae can be used in anti-adhesive therapies against bacterial infections, both in cold- and warm-blooded animals . In this study we found that adhesion of the human pathogen Helicobacter pylori to the HeLa S3 cell line, and adhesion of the fish pathogens Vibrio campbellii, V . ordalii, Streptococcus saprophyticus, and Aeromonas veronii to spotted sand bass primary tissue culture cells, can be effectively blocked with the various sulphated exopolysaccharides used. J Clin Periodontol, 2000 May, 27(5), 370 - 3 Effect of an essential oil-containing antiseptic mouthrinse on induction of platelet aggregation by oral bacteria in vitro; Whitaker EJ et al.; BACKGROUND: With an increasing body of data suggesting an association between periodontitis and cardiovascular disease, studies have been conducted to elucidate potential mechanisms by which oral bacteria might exert systemic effects . 2 oral bacteria, Streptococcus sanguis and Porphyromonas gingivalis, have been shown to induce platelet aggregation in vitro . This study was conducted to determine the effect of treatment with an essential oil mouthrinse (Listerine Antiseptic) on the platelet-aggregating activity of these organisms . METHOD: Bacteria were grown under standard culture conditions . S . sanguis ATCC strain 10556 was exposed for 3 min to the essential oil mouthrinse at either full strength or a 1:1 dilution, while P . gingivalis FDC strain 381 was exposed to the essential oil mouthrinse at a 1:10 dilution . Positive control cells were treated with Hanks balanced salt solution (HBSS) . Aggregation was measured using a recording platelet aggregometer . The assay of each organism in its respective mouthrinse dilution(s) or HBSS was repeated 5 times . RESULTS: In all cases, the HBSS-treated organisms induced platelet aggregation, with mean(+/-S.E.) lag times of 12.30 (+/-1.36) min and 11.36 (+/-0.58) min for P . gingivalis and S . sanguis, respectively . In contrast, treatment with the essential oil mouthrinse completely inhibited the platelet aggregating activity of P . gingivalis and of S . sanguis exposed to the 1:1 mouthrinse dilution in all assays; the aggregating activity of S . sanguis treated with full-strength mouthrinse was completely inhibited in 4 of 5 assays, and inhibited by 75% in the 5th, for a mean inhibition of 95 +/- 1.5% . CONCLUSION: This study provides additional evidence that the essential oil mouthrinse can interfere with bacterial cell surface-associated activities which may have clinical relevance. Microbiology, 2000 Jun, 146 ( Pt 6), 1361 - 9 Streptococcus equi with truncated M-proteins isolated from outwardly healthy horses; Chanter N et al.; The M-protein genes of Streptococcus equi isolated from 17 outwardly healthy horses after 4 strangles outbreaks had ended, including a quarantined animal, were compared with those of S . equi isolates from 167 active cases of strangles across 4 countries . The healthy horses included 16 persistent S . equi carriers, at least one from each of the four outbreaks . These carriers, despite being outwardly healthy, had empyema of the guttural pouch(es), an enlargement of the equine Eustachian tube . A persistent carrier from two of these outbreaks, the quarantined animal and a healthy animal with normal guttural pouches, from which S . equi was isolated only once, were colonized by variant S . equi with truncated M-protein genes (24% of outwardly healthy animals with S . equi) . The truncated M-protein genes had in-frame deletions in slightly different positions between the signal sequence and the central repeat region, equivalent to approximately 20% of the mature expressed protein . Immunoblotting with antibody to recombinant M-protein confirmed that the variants expressed a truncated form of the M-protein . In contrast to the outwardly healthy S . equi carriers, only 1/167 of S . equi isolates from strangles cases possessed a truncated M-protein gene (<1%; Fisher's exact test, P=0.0002) . Compared with isolates from healthy horses with a truncated M-protein, much more of the N terminus of the truncated M-protein was retained in the variant S . equi from a strangles case . Variant S . equi from outwardly healthy animals were more susceptible to phagocytosis by neutrophils in vitro than typical isolates . This is the first report of detection of S . equi with a truncated M-protein . The distribution of the variants between strangles cases and carriers suggests that the 80% of the M-protein retained in the variants may contribute to colonization whilst the deleted portion of the gene may be needed for full virulence. Microbiology, 2000 Jun, 146 ( Pt 6), 1267 - 73 Quantitative detection of Streptococcus pneumoniae cells harbouring single or multiple copies of the gene encoding the green fluorescent protein; Acebo P et al.; A modified gfp gene from Aequorea victoria, encoding a variant of the green fluorescent protein (GFP), was subcloned into the mobilizable plasmid pMV158 . gfp was placed under the control of the inducible P(M) promoter of the Streptococcus pneumoniae gene malM, cloned in plasmid pLS70 . The P(M) promoter is regulated by the product of the pneumococcal malR gene, which is inactivated by growing the cells in maltose-containing media . By homologous recombination, the P(M)-gfp construction was integrated into the host chromosome in a single copy . In both conditions (single and multiple copies), the pneumococcal cells were able to express GFP in an inducible or constitutive form, depending on whether the S . pneumoniae strain harboured a wild-type or a mutant malR gene . Quantification of the levels of GFP expressed by cultures supplemented with sucrose or maltose as carbon sources was feasible by fluorescence spectroscopy . Phase-contrast and fluorescence microscopy allowed pneumococcal cells expressing GFP in mixed cultures to be distinguished from those not carrying the gfp gene. Mol Microbiol, 2000 May, 36(3), 726 - 36 Species-specific binding of human secretory component to SpsA protein of Streptococcus pneumoniae via a hexapeptide motif; Hammerschmidt S et al.; SpsA, a pneumococcal surface protein belonging to the family of choline-binding proteins, interacts specifically with secretory immunglobulin A (SIgA) via the secretory component (SC) . SIgA and free SC from mouse, rat, rabbit and guinea-pig failed to interact with SpsA indicating species-specific binding to human SIgA and SC . SpsA is the only pneumococcal receptor molecule for SIgA and SC as confirmed by complete loss of SIgA and SC binding to a spsA mutant . Analysis of recombinant SpsA fusion proteins showed that the binding domain is located in the N-terminal region of SpsA . By the use of different truncated N-terminal SpsA fusion proteins, the minimum binding domain was shown to be composed of 112 amino acids (residues 172-283) . The sequence of this 112-amino-acids domain was used to spot synthesize 34 overlapping peptides, consisting of 15 amino acids each, with an offset of three amino acids on a cellulose membrane . One of the peptides reacted specifically with both SIgA and SC . By using a second membrane with immobilized synthetic peptides of decreasing length containing parts of the identified 15-amino-acid motif a hexapeptide, YRNYPT was identified as the binding motif for SC and SIgA . SpsA proteins with a size smaller than the assay-positive domain of 112 amino acids were able to inhibit the interaction of SIgA and pneumococci provided they contained the binding motif . The results indicated that the hexapeptide YRNYPT located in SpsA of pneumococcal strain type 1 (ATCC 33400) between amino acids 198 and 203 is involved in SIgA and SC binding . Because synthetic peptides containing only parts of the hexapeptide also assayed positive, these results further suggest that at least the amino acids YPT of the identified hexapeptide are critical for binding to SC and SIgA . Amino acid substitutions in the identified putative binding motif abolished SC-/SIgA-binding activity of the mutated SpsA protein, confirming the functional activity of this hexapeptide and the critical role of the amino acids YPT in SC and SIgA binding . Identification of this motif, which is highly conserved in SpsA protein among different serotypes, might contribute towards a new peptide based vaccine strategy. Mol Microbiol, 2000 May, 36(3), 688 - 96 Competence regulation by oxygen in Streptococcus pneumoniae: involvement of ciaRH and comCDE; Echenique JR et al.; Anaerobic aerotolerant Streptococcus pneumoniae modulates its genetic transformability and its virulence in response to the oxygen concentration . The activity of a single protein encoded by nox and showing NADH oxidase activity is involved in these adaptive responses to O2 . Northern blot analysis of wild-type cultures grown under aerobic and microaerobic conditions indicated transcriptional control of comCDE by O2 . An O2-independent mutant strain carrying the gain-of-function mutation comE38KE was isolated and its analysis showed that ComE is a key point in competence stimulation by O2 . Plasmid insertion mutations in ciaRH revealed that this two component signal-transducing system negatively regulates comCDE transcription . The level of comCDE transcripts appears as a major control point in competence regulation by O2 and also by growth phase and cell density. J Clin Neurosci, 1999 Sep, 6(5), 415 - 418 Polymicrobial brain stem abscess due to Streptococcus anginosus and Actinomyces species; Kalarostaghi AH et al.; This report describes a rare case of a pyogenic brain stem abscess . The lesion was readily identified by computed tomographic (CT) scan and magnetic resonance imaging (MRI) . Streptococcus anginosus was grown from the pus and Actinomyces colonies were found on histopathology . The lesion was successfully treated with stereotactic surgery and antibiotic therapy . A review of the relevant literature including the role of stereotaxy in the treatment of the brain stem abscess is discussed . Int J Syst Evol Microbiol, 2000 May, 50 Pt 3, 1073 - 9 The Streptococcus anginosus species comprises five 16S rRNA ribogroups with different phenotypic characteristics and clinical relevance; Jacobs JA et al.; A collection of 267 consecutively isolated Streptococcus anginosus strains was screened for the prevalence of previously described 'motile' strains by hybridization with oligonucleotide probes in a reverse line blot assay . The motile strains represented 101 (37.8%) of the S . anginosus strains . The vast majority of these strains fermented mannitol and raffinose, whereas most other S . anginosus strains did not (P<0.001) . Most (83/101) of the motile strains were recovered from the urogenital tract (including five strains from neonatal surveillance cultures) and only a minority (36) of them were associated with infection-related samples (P<0.001) . Strains that hybridized with the same oligonucleotide probes as the type strain S . anginosus ATCC 33397T (= NCTC 10713T) were designated ATCC-like strains . They accounted for 74 (27.7%) of the strains examined, were commonly distributed among the different body parts and were significantly more associated with infection-related samples . Three other hybridization patterns were recognized in the reverse line blot assay, ribogroup I (n = 51), ribogroup II (n = 21) and ribogroup III (n = 19) . Ribogroup II strains were significantly more frequently recovered from the abdominal cavity and were associated with infection-related samples . Ribogroup I included the majority of the S . anginosus strains that carried Lancefield group C . Comparison of the nearly complete 16S rRNA sequence of two representative strains of each ribogroup revealed that all five ribogroups were closely related (>97% sequence similarities), and that most sequence divergences between the ribogroups occurred in the 1024-1064 bp region of the 16S rRNA gene . The present data confirm the heterogeneity within the S . anginosus species. Biochemistry, 2000 Jun 13, 39(23), 7012 - 23 The first structure of UDP-glucose dehydrogenase reveals the catalytic residues necessary for the two-fold oxidation; Campbell RE et al.; Bacterial UDP-glucose dehydrogenase (UDPGlcDH) is essential for formation of the antiphagocytic capsule that protects many virulent bacteria such as Streptococcus pyogenes andStreptococcus pneumoniae type 3 from the host's immune system . We have determined the X-ray structures of both native and Cys260Ser UDPGlcDH from S . pyogenes (74% similarity to S . pneumoniae) in ternary complexes with UDP-xylose/NAD(+) and UDP-glucuronic acid/NAD(H), respectively . The 402 residue homodimeric UDPGlcDH is composed of an N-terminal NAD(+) dinucleotide binding domain and a C-terminal UDP-sugar binding domain connected by a long (48 A) central alpha-helix . The first 290 residues of UDPGlcDH share structural homology with 6-phosphogluconate dehydrogenase, including conservation of an active site lysine and asparagine that are implicated in the enzyme mechanism . Also proposed to participate in the catalytic mechanism are a threonine and a glutamate that hydrogen bond to a conserved active site water molecule suitably positioned for general acid/base catalysis. J Infect, 2000 Mar, 40(2), 141 - 4 Carriage of penicillin-susceptible and non-susceptible pneumococci in healthy young children in Göteborg, Sweden; Borres MP et al.; OBJECTIVES: To study carriage of Streptococcus pneumoniae among healthy young children, determine the proportion of strains with decreased susceptibility to penicillin, and study possible risk factors for the carriage of penicillin-resistant strains . METHODS: Between February 1996 and February 1997, 620 healthy, 18-month-old children in Goteborg, Sweden were screened for carriage of S . pneumoniae with decreased susceptibility to penicillin . Nasopharyngeal samples were obtained from children visiting child health centres for routine health control . RESULTS: Streptococus pneumoniae was found in 322 samples and 18 strains (5.6%, CI95 3.4; 8.8) of all pneumococci showed decreased susceptibility to penicillin G with minimum inhibitory concentrations (MICs) ranging from 0.125 to 1.0 mg/l . The proportion of strains with decreased susceptibility was similar to that found in a laboratory-based material (6%), from the same geographical area and time period . A majority of the children with strains with decreased susceptibility to penicillin (n = 11) were not attending day-care centres . CONCLUSIONS: The prevalence of S . pneumoniae with reduced susceptibility to penicillin is still low in unselected healthy Swedish children. Am J Infect Control, 2000 Jun, 28(3), 239 - 43 Streptococcus pneumoniae: bacteremia in an era of penicillin resistance; Castillo EM et al.; BACKGROUND: The proportion of penicillin-resistant Streptococcus pneumoniae isolates and associated risk factors varies by geographic area in the United States . We conducted a retrospective study to determine the extent of penicillin-nonsusceptible S pneumoniae bacteremia and associated risk factors in a tertiary care medical center in San Diego . METHODS: Patients with S pneumoniae bacteremia at the University of California, San Diego Medical Center from September 15, 1991, through July 31, 1998, were identified by hospital-based computerized microbiology records . Hospital records included demographic information, patient data, and antibiotic prescription records for patients with bacteremia as a result of S pneumoniae . Univariate and multivariate analyses were used to determine risk factors for penicillin-nonsusceptible S pneumoniae bacteremia . RESULTS: Of 281 isolates of S pneumoniae identified, 192 (68%) were from hospitalized patients . After controlling for other factors, patients from 1 to 5 years of age (P = .01; odds ratio {OR} = 3.96; 95% CI, 1.50 to 10.44), 6 to 18 years of age (P =.04; OR = 6.42; 95% CI, 1.13 to 36.51), and HIV seropositive patients (P =.002; OR = 5.12; 95% CI, 1.83 to 14.32) were more likely to have penicillin-nonsusceptible S pneumoniae bacteremia . There was a significant increasing trend of penicillin-nonsusceptible S pneumoniae bacteremia from 14% in 1991 to 42% in 1998 (P = .001; OR = 1.42; 95% CI, 1.16 to 1.73); this included only 2 isolates that were highly resistant to penicillin . There was no increase in mortality in patients who had penicillin-nonsusceptible S pneumoniae bacteremia . CONCLUSION: With the increase in S pneumoniae resistance to penicillin, it is important to continue surveillance of infections caused by S pneumoniae . Hospital-based studies are useful for tracking epidemiologically important pathogens. Prim, Care Update Ob Gyns . 1998 Jul 1, 5(4), 148 - 149 Strategies to decrease costs associated with GBS prophylaxis in preterm gestations; Nguyen T et al.; Objective: 1) To evaluate the costs associated with a practice of routinely culturing women for Group B beta-Streptococcus (GBS) who are at risk for preterm delivery . 2) To evaluate the charges associated with a policy of empiric antibiotic therapy in women suspected of imminent delivery prior to 37 weeks gestation.Methods: In our hospital, women who present with preterm contractions (PTC), preterm labor (defined as uterine contractions resulting in cervical change, PTL), and preterm rupture of the membranes (PROM) were cultured for GBS . Women with PTL and PROM received parenteral antibiotic therapy pending availability of culture results (48 hours) . We reviewed the records of women who participated in a study to determine the sensitivity and specificity of a rapid test for GBS (Am J Obstet Gynecol 1997;176:S35) . Results of the Lim broth culture, our gold standard, were used for this analysis . The charges for performing cultures ($32/culture) and administering intravenous ampicillin ($54/dose) were calculated.Results: There were 118 women with PTC, 52 women with PTL, and 64 with PROM . Thirty-four (14.5%) of the cultures were positive . The results are presented below.In women with PTC, the incidence of GBS was 12.7% . The culture results were available and guided care in only the 6 women who delivered between 2 and 7 days . In women with PTL the incidence of positive cultures was 11.5% . All of the women received antibiotics pending results of cultures . The majority of the women had delivery delayed 48 hours until results were available . Care was modified in the 7 women who delivered between 2 and 7 days . In women with PROM the incidence of GBS was 20.3% . The culture results were available and guided therapy in 11 women.Conclusions: Our findings suggest that GBS cultures have limited clinical value in women with PTC . Only 6 women, 5.5%, had their care modified as a result of the cultures, at a cost of $3776 . In women with PTL, we over-treated the majority of women with antibiotics, most of whom delivered after culture results were available . Cultures had minimal impact on management . Antibiotics should be reserved for women whose labor is progressing on tocolysis . In women with PROM, most delivered prior to availability of culture results . We would have saved $2048 had no cultures been obtained . These results are probably irrelevant, if routine antibiotic administration is utilized in PROM to prolong latency intervals regardless of GBS status. Br J Ophthalmol, 2000 Jun, 84(6), 614 - 7 Management of orbital lymphangioma using intralesional injection of OK-432; Suzuki Y et al.; AIM: To treat orbital lymphangioma with an intralesional injection of OK-432 (group A Streptococcus pyogenes of human origin) . METHOD: A 14 year old boy had a right orbital cystic lymphangioma . The visual acuity in the eye was 20/28 . In an initial treatment, 0.02 mg of OK-432, was injected into the tumour after aspiration of the fluid contents, but no effect was seen . The second treatment was performed with 0.04 mg of OK-432 . RESULT: 4 months later, the lesion had totally shrunk to fibrous tissue . The side effects were fever, a local inflammatory reaction lasting 3 days, and increased intraocular pressure, which was managed by draining the fluid contents . Visual acuity improved to 20/15, and the visual field defect and restriction of eye movement seen before treatment disappeared . No recurrence was noted 1 year after treatment . CONCLUSION: An intralesional injection of OK-432 shrunk the lymphangioma without functional disturbance and scar in the facial skin . OK-432 may be useful for orbital lymphangioma, but further studies are still warranted to determine efficacy, complications, and the optimal dose for safe treatment. J Infect Dis, 2000 Jun, 181(6), 2095 - 8 Epub 2000 May 26. Rifampin reduces production of reactive oxygen species of cerebrospinal fluid phagocytes and hippocampal neuronal apoptosis in experimental Streptococcus pneumoniae meningitis; Bottcher T et al.; Bacterial compounds induce the production of reactive oxygen species (ROS) in meningitis . Rifampin releases smaller quantities of proinflammatory compounds from Streptococcus pneumoniae than do beta-lactam antibiotics . Therefore, rabbits infected intracisternally with S . pneumoniae were treated intravenously either with rifampin 5 mg/kg/h or ceftriaxone 10 mg/kg/h (n=9 each) . Before initiation of antibiotic treatment, a strong positive correlation between ROS production of cerebrospinal fluid (CSF) phagocyte populations and bacterial CSF titers was observed (granulocytes: rs=.90, P<.0001; monocytes: rs=.81, P<.0001) . CSF leukocytes from rifampin-treated rabbits produced less ROS (monocytes at 2 h after initiation of treatment: P=.045; at 5 h: P=.014; granulocytes at 5 h: P=.036) than did leukocytes from animals receiving ceftriaxone . The CSF malondialdehyde concentrations and the density of apoptotic neurons in the dentate gyrus were lower in rifampin- than in ceftriaxone-treated animals (P=.002 and.005) . The use of rifampin to reduce the release of ROS and to decrease secondary brain injury appears promising. J Infect Dis, 2000 Jun, 181(6), 1983 - 8 Epub 2000 May 22. Sequential colonization by Streptococcus pneumoniae of healthy children living in an orphanage; Raymond J et al.; A prospective study of nasopharyngeal colonization by Streptococcus pneumoniae in the exceptional conditions of a closed community of abandoned children was done over a 1-year period; 71 children (age <24 months) were studied monthly . S . pneumoniae was isolated from 58 (81.7%), and 94.5% of the 111 isolates were resistant to penicillin . The mean rate of carriage was estimated at 57.4%, ranging from 42.8% to 70.4% . Children were sequentially colonized by a mean of 3 different isolates . The mean duration of carriage for a given isolate was approximately 2.2 months . Serotyping and molecular typing by pulsed-field gel electrophoresis showed that children were colonized by a limited number of clones belonging to only 4 serotypes and 4 pulsotypes . These clones rapidly spread in the community and colonized the children in waves, with a rapid turnover of S . pneumoniae isolates, facilitated by close contact between children. J Infect Dis, 2000 Jun, 181(6), 1979 - 82 Epub 2000 May 31. Low cord blood type 14 pneumococcal IgG1 but not IgG2 antibody predicts early infant otitis media; Lockhart NJ et al.; Type-specific IgG1 and IgG2 antibodies to Streptococcus pneumoniae capsular polysaccharides 14 and 19F were measured in cord blood samples from 425 neonates, to determine which antibody subclass was most strongly associated with otitis media (OM) during the first 6 months of life (early OM) . Early OM was significantly associated with type 14 IgG1 antibody in the lowest antibody quartile (P=.055) but not with type 19F IgG1 antibody or with either IgG2 antibody . IgG1 and IgG2 antibodies were significantly intercorrelated for type 14 (r=.52, P<.001) and type 19F (r=.38, P<.001) . Multivariate analysis revealed that having type 14 IgG1 antibody in the lowest quartile, child care attendance, and sibling and maternal OM history were independent risk factors for early OM . Although type-specific pneumococcal IgG2 antibody concentrations were significantly higher than IgG1 concentrations, IgG2 antibodies apparently are not protective against OM during early infancy. J Infect Dis, 2000 Jun, 181(6), 1971 - 8 Epub 2000 May 31. Molecular epidemiology survey of penicillin-susceptible and -resistant Streptococcus pneumoniae recovered from patients with meningitis in France; Doit C et al.; The genetic diversity of Streptococcus pneumoniae isolates (n=291) recovered from cerebrospinal fluid of patients with meningitis in France was investigated by restriction fragment length polymorphism analysis of the ribosomal RNA gene regions and of the pbp2b and 2x genes . Statistical analysis of the data by factorial analysis of correspondence established the following: penicillin-susceptible isolates had a high level of genetic diversity, especially those belonging to serogroups frequently associated with carriage; capsular serotype switches could occur among penicillin-susceptible and -resistant isolates; and the mechanisms of acquired penicillin resistance were clearly distinct in isolates with penicillin minimum inhibitory concentration (MIC) values <1 mg/L and isolates with penicillin MIC values >/=1 mg/L . Thus, an increase in the penicillin MIC for a given strain, from intermediate to high-level resistance would be a rare event. J Fam Pract, 2000 May, 49(5), 447 - 8 The necessity of both anorectal and vaginal cultures for group B streptococcus screening during pregnancy; Quinlan JD et al.; BACKGROUND: Group B streptococcus (GBS) sepsis affects approximately 2 of every 1000 newborns . In an effort to decrease the incidence of neonatal GBS infection, the Centers for Disease Control and Prevention have established guidelines for screening and treatment during pregnancy . One strategy includes obtaining both vaginal and anorectal GBS cultures, then treating patients whose cultures are positive . Many of our patients are reluctant to undergo anorectal cultures . We conducted a study to determine whether performing cultures of both the vagina and anorectum would change patient management . METHODS: We obtained vaginal and anorectal GBS cultures from 222 consecutive patients at 35 to 37 weeks' gestation . RESULTS: Fifty-four patients (24.3%) had positive GBS cultures . Of those women, 10 (18.5%) had negative vaginal but positive rectal cultures . Thus, nearly one fifth of the patients with GBS colonization would not have received intrapartum antibiotics if only vaginal cultures had been performed . CONCLUSIONS: Health care providers caring for pregnant patients should consider obtaining both vaginal and anorectal cultures when screening for Group B streptococcus. Eur Respir J, 1999 Jan, 13(1), 175 - 9 Search for agents causing atypical pneumonia in HIV-positive patients by inhibitor-controlled PCR assays; Tarp B et al.; Pneumonia is one of the most frequent complications in acquired immunodeficiency syndrome-patients with Pneumocystis carinii as the leading cause . The true prevalence of atypical agents such as Chlamydia pneumoniae, C . trachomatis, Legionella pneumophila and Mycoplasma pneumoniae in this population of patients is unknown as the currently used method for diagnosing these agents is measurement of antibody levels . However, this method is of limited value in human immunodeficiency virus (HIV)-positive patients who may have a compromised antibody response . To evaluate the prevalence of Chlamydia spp., Legionella spp . and M . pneumoniae in HIV-infected patients with pulmonary disease, this retrospective study has applied inhibitor-controlled polymerase chain reaction analyses on 103 bronchoalveolar lavage (BAL) fluids representing 103 episodes of pneumonia in 83 HIV-positive patients . L . pneumophila was detected in 1% of the BAL fluids and M . pneumoniae was found as a coexisting pathogen in 2% of the samples . Chlamydia spp . could not be detected in any of the BAL fluids . By culture and staining methods 106 other microorganisms were detected with P . carinii and Streptococcus pneumoniae as the most frequently occurring . Pneumonia due to Chlamydia pneumoniae, Legionella pneumophila or Mycoplasma pneumoniae seems to be rare in Danish human immunodeficiency virus-infected patients, but might be considered as a possible cause in cases of treatment failure. Nippon Ganka Gakkai Zasshi, 2000 May, 104(5), 328 - 33 {Molecular biological analysis of retinal and streptococcal heat-shock protein 60}; Tanaka T et al.; PURPOSE: The observation of recurrent oral aphtha preceding ocular inflammation in patients with Behcet's disease suggests a role of oral Streptococcus in the etiology of this disease . Heat-treated Streptococcus antigen can induce ocular inflammation or systemic symptoms in Behcet's disease patients . Furthermore, the presence of an autoantibody against retinal heat-shock protein 60 (HSP 60) has been detected in the sera of these patients . Injection of extracted retinal HSP 60 also induces experimental uveitis in treated rats . The characteristics of retinal HSP 60 and HSP 60 from S . pyogenes were evaluated using a molecular biological approach . METHODS: The gene encoding HSP 60 was isolated by polymerase chain reaction (PCR) from a bovine retinal cDNA library and from S . pyogenes DNA . The DNA sequence of the HSP 60 coding region was determined, and the amino acid sequences of the encoded proteins were predicted from the DNA sequence . The synthetic peptide (50 nmol) was emulsified with Freund's complete adjuvant and injected into rats . RESULTS: Comparison of the amino acid sequences of Streptococcal and bovine retinal HSP 60 revealed about 200 residue regions with 47% homology . Experimental uveitis was mainly induced in rats inoculated with retinal HSP 60-derived peptide or Streptococcus HSP 60-derived peptide that is equivalent to residues 245-259 of human HSP 65 . DISCUSSION: The retinal and Streptococcal HSP 60 amino acid composition is thought to be important and useful for investigating the mechanisms involved in the induction of Behcet's disease. Rev Med Chil, 1999 Dec, 127(12), 1462 - 8 {Dental fluorosis: quantification of Streptococcus mutans in school children from Mamiña, Chile . A longitudinal study}; Linossier A et al.; BACKGROUND: High fluorine concentrations in drinking water are associated with a decrease in the amount of salivary S mutants . Taking into account that clinical dental fluorosis can appear with 1.5 ppm of fluorine in the drinking water, fluorine concentrations in Mamina is 2.4 ppm . AIM: To quantify salivary S mutans in school age children from Mamina, a zone with a high fluorine content in the drinking water, during one year . MATERIAL AND METHODS: During 1997 and 1998, dental health was assessed and salivary samples were obtained from 51 children (27 male) aged 10 +/- 2 years to quantify S mutans . RESULTS: Most children studied had more than 10(5) salivary S mutans colony forming units . No changes in the rates of infection or dental health characteristics were observed during the observation year . CONCLUSIONS: High fluorine content in the drinking water did not have an effect on salivary S mutans infection in this population. Rev Med Chil, 1999 Dec, 127(12), 1447 - 52 {Emergence of resistance to macrolides in Streptococcus pyogenes}; Vinagre C et al.; BACKGROUND: Diseases produced by Streptoccocus pyogenes are still a problem in Chile, as in the rest of the world . It exhibits in vitro susceptibility to different antimicrobials, but penicillin continues to be the treatment of choice . Alternative drugs have been developed for allergic patients, such as erythromycin, new macrolides and cephalosporins . Nevertheless, resistant strains are appearing due to the indiscriminate use of macrolides . AIM: To assess present antimicrobial susceptibility of S Pyogenes strains isolated from chilean patients . MATERIAL AND METHODS: The susceptibility to penicillin, macrolides, clindamycin, cephalotin and vancomycin of 153 S Pyogenes strains, obtained from different health centers of the Metropolitan Region and isolated between 1996 and 1998, was assessed using the Kirby-Bauer method . Agar dilution minimal inhibitory concentration was then determined to macrolide resistant strains . RESULTS: All strains were susceptible to penicillin . There was a 7.2% cross-resistance to macrolides . CONCLUSIONS: These results confirm that S Pyogenes resistance to macrolides has increased considerably in the Metropolitan Region of Chile during the last years. J Clin Microbiol, 2000 Jun, 38(6), 2450 - 2 Recurrent bacteremic peritonitis caused by Enterococcus cecorum in a patient with liver cirrhosis; Hsueh PR et al.; Enterococcus cecorum (formerly Streptococcus cecorum), originally isolated from poultry intestines, has rarely been encountered in human diseases . A 60-year-old man with liver cirrhosis and hepatocellular carcinoma developed peritonitis on the seventh day of his hospitalization . Cultures of one blood sample and one ascites fluid sample obtained on that day both grew E . cecorum . The patient received intravenous cefoxitin therapy and initially responded well . Unfortunately, another episode of peritonitis associated with septic shock developed 24 days after the start of treatment, and culture of one blood specimen yielded the same organism . The isolates were identified by the conventional biochemical tests, the API Rapid ID 32 Strep system, and the API ZYM system (both systems from bioMerieux, Marcy L'Etoile, France) and were further confirmed by cellular fatty acid chromatography and 16S rRNA gene partial sequencing . The identical biotype, antibiotype, and random amplified polymorphic DNA pattern of the three isolates documented the long-term persistence of this organism in the patient . To the best of our knowledge, this is the first clinical description of recurrent bacteremic peritonitis caused by E . cecorum. J Clin Microbiol, 2000 Jun, 38(6), 2141 - 9 Macrorestriction fingerprinting of "Streptococcus milleri" group bacteria by pulsed-field gel electrophoresis; Bartie KL et al.; Although isolates of the "Streptococcus milleri" group (SMG) of bacteria are regarded as members of the commensal microflora of the body, they are frequently encountered in purulent infections from a range of body sites . The genetic diversity of 91 epidemiologically unrelated SMG isolates (including 37 commensal strains and 49 disease-associated strains) was analyzed by macrorestriction fingerprinting (MF) . The genomes were digested with SmaI and ApaI independently, and fragments were resolved by pulsed-field gel electrophoresis . Similarities between banding profiles were determined, and strains were clustered on this basis into dendrograms . In common with other commensal species that have been examined by MF, considerable genetic diversity was revealed . In addition, the clustering of strains tended to support the current taxonomic position of this heterogeneous group . The present study has shown that MF is a powerful tool for characterization of SMG strains and that its use is likely to be of great value in epidemiological and population genetic studies of this group of bacteria. J Clin Microbiol, 2000 Jun, 38(6), 2103 - 7 High rate of tetracycline resistance in Streptococcus pyogenes in Iran: an epidemiological study; Jasir A et al.; Streptococcus pyogenes, a major human pathogen, is still considered susceptible to beta-lactams, but for other relevant antibiotics, highly variable resistance rates have been reported . Since no data were available from Iran, we tested 1,335 throat isolates from two different regions of the country for their antibiotic susceptibilities and, for comparison, a collection of 80 strains isolated from 1989 to 1991 . Erythromycin resistance was uncommon (0.6%), whereas an overall high rate of tetracycline resistance was found, increasing between 1989-1991 and 1995-1997 from 23 to 42% . The tetracycline-resistant strains belonged to more than 10 different T types, the majority being types 4, 11, and B3264 . By conventional M typing of 406 tetracycline-resistant isolates, more than 20 different M types were found . Approximately 50% of the strains were nontypeable by T agglutination as well as serological M typing; however, by genotyping by a combined PCR-capture-enzyme-linked immunosorbent assay, many of these strains were successfully emm typed . We conclude that the high rate of tetracycline resistance among Iranian S . pyogenes isolates is due to multiclonal dissemination of resistance within the streptococcal population rather than epidemic spread of single clones. Eur J Clin Microbiol Infect Dis, 2000 Apr, 19(4), 288 - 93 Carriage of antibiotic-resistant Streptococcus pneumoniae in Greek infants and toddlers; Syrogiannopoulos GA et al.; The prevalence, resistance patterns and serotypes of antibiotic-resistant Streptococcus pneumoniae strains recovered from Greek carriers under 24 months of age were studied . From February 1997 to April 1998, nasopharyngeal cultures were performed in 1,269 children (ages 2-23 months, median 11 months) living in various areas of central and southern Greece . Resistance (including both intermediate and resistant isolates) to one or more antimicrobial agents was found in 132 of the 421 (31%) Streptococcus pneumoniae isolates, as follows: penicillin, 9% intermediate, 7.6% resistant; cefotaxime, 5.2% intermediate, 0.5% resistant; erythromycin, 0.7% intermediate, 18.1% resistant; clindamycin, 0.2% intermediate, 12.4% resistant; tetracycline, 0.7% intermediate, 16.4% resistant; chloramphenicol, 12.4% resistant; and trimethoprim-sulfamethoxazole, 3.8% intermediate, 14.3% resistant . The MICs of penicillin for 66% of the penicillin-nonsusceptible pneumococci were 1-4 microg/ml . Multidrug resistance was found in 64% of penicillin-nonsusceptible and 37% of penicillin-susceptible strains . Sixty-two percent of the penicillin-susceptible, multidrug-resistant strains belonged to serotype 6B and were resistant to all five non-beta-lactam agents tested . This notable serotype 6B resistance pattern was described for the first time in a previous study performed from December 1995 to February 1996 in the city of Patras, southwestern Greece . Seventy-two percent of antibiotic-resistant isolates belonged to serotypes 6B, 9V, 14, 18C, 19F and 23F . These results document the spread of resistant pneumococcal strains in central and southern Greece, many of which are multidrug resistant. Protein Expr Purif, 2000 Jun, 19(1), 158 - 72 Expression of active monomeric and dimeric nuclease A from the gram-positive Streptococcus gordonii surface protein expression system; Dutton EK et al.; We used the surface protein expression (SPEX) system to express an anchored and a secreted form of staphylococcal nuclease A (NucA) from gram-positive bacteria . NucA is a small ( approximately 18 kDa), extracellular, monomeric enzyme from Staphylococcus aureus . A deletion of amino acids 114-119 causes monomeric NucA to form homodimers . The DNA sequence encoding either wild-type or deletion mutant NucA was cloned via homologous recombination into Streptococcus gordonii . S . gordonii strains expressing either anchored or secreted, monomeric or dimeric NucA were isolated and tested for enzymatic activity using a novel fluorescence enzyme assay . We show that active monomeric and dimeric NucA enzyme can be expressed either anchored on the cell surface or secreted into the culture medium . The activity of the dimer NucA was approximately 100-fold less than the monomer . Secreted and anchored, monomeric NucA migrated on SDS-polyacrylamide gels at approximately 18 or approximately 30 kDa, respectively . In addition, similar to S . aureus NucA, the S . gordonii recombinant NucA enzyme was dependent on CaCl(2) and was heat stable . In contrast, however, the recombinant NucA activity was maximal at pH 7.0-7.5 whereas S . aureus NucA was maximal at pH 9.0 . These results show, for the first time, expression of active enzyme and polymeric protein in secreted and anchored forms using SPEX . This further demonstrates the utility of this gram-positive surface protein expression system as a potential commensal bacterial delivery system for active, therapeutic enzymes, biopharmaceuticals, or vaccines . Lancet, 2000 May 20, 355(9217), 1776 - 80 Epidemic nephritis in Nova Serrana, Brazil; Balter S et al.; BACKGROUND: Outbreaks of nephritis have been rare since the 1970s . From December, 1997, to July, 1998, 253 cases of acute nephritis were identified in Nova Serrana, Brazil . Seven patients required dialysis, and three patients died . We did a case-control study to investigate the cause of the outbreak . METHODS: Using a matched cluster design, we examined seven recent patients, their family members (n=23), and members of neighbourhood-matched control households (n=22) . We subsequently interviewed 50 patients and 50 matched controls about exposure to various dairy products . We also cultured dairy foods and took udder-swab and milk samples from cows . FINDINGS: Throat cultures indicated that nephritis was associated with group C Streptococcus equi subspecies zooepidemicus, a cause of bovine mastitis . S . zooepidemicus was detected in four of seven case households (six of 30 people) and no control households (p=0.09) . Patients were more likely than matched controls to have consumed a locally produced cheese called queijo fresco (matched odds ratio 2.1, p=0.05) . The nephritis attack rate was 4.5 per 1000 in Nova Serrana but 18 per 1000 in the village Quilombo do Gaia (p=0.003) . The largest supplier of unpasteurized queijo fresco was a farm in Quilombo do Gaia . S . zooepidemicus was not detected in food samples or in swabs collected from cows in August, 1998, although mastitis was evident among cows on the suspected farm . Throat cultures of the two women who prepared cheese on this farm yielded the outbreak strain of S . zooepidemicus . After the cheese was removed from the distribution system, no further cases were reported . INTERPRETATION: A large outbreak of glomerulonephritis was attributed to S . zooepidemicus in unpasteurised cheese . This outbreak highlights the dangers of consuming unpasteurized dairy products and need for global efforts to promote food safety. Cornea, 2000 May, 19(3), 297 - 300 A devastating ocular pathogen: beta-streptococcus Group G; Ritterband DC et al.; PURPOSE: To report the clinical findings, treatment, and outcomes of four cases of beta-streptococcus Group G (BHS-G) ocular infection . METHODS: The medical and microbiologic records of four cases of BHS-G ocular infection were retrospectively reviewed . RESULTS: Two cases of BHS-G endophthalmitis and two cases of BHS-G keratitis were recorded . Three patients developed fulminant infection within 12 hours of the onset of symptoms . One patient's history was incomplete . One patient developed endophthalmitis from a contaminated donor button; another following cataract surgery . One developed keratitis in a keratoplasty suture tract; and another patient developed a corneal abscess after being struck with a tree branch . The patient with the contaminated donor button developed overwhelming endophthalmitis resulting in no light perception vision, severe pain, and evisceration . The postoperative cataract patient developed a purulent endophthalmitis and is still hypotonus with light perception vision . The second keratitis patient developed a significant suture abscess with marked stromal loss but eventually healed . The traumatic keratitis patient developed a large ulcer with hypopyon and descemetocele but was lost to follow-up . CONCLUSIONS: This is the first report of a series of BHS-G ocular infections . The ocular infections were characterized by rapid onset, extreme inflammation, and--despite in vitro antibiotic sensitivity--a poor or sluggish response to antibiotic therapy. Microbiology, 2000 May, 146 ( Pt 5), 1187 - 94 Localization and characterization of the ligand-binding domain of the fibrinogen-binding protein (FgBP) of Streptococcus equi subsp . equi; Meehan M et al.; The group C streptococcus Streptococcus equi subsp . equi possesses a 498-residue major cell-wall-associated protein (FgBP) which binds horse fibrinogen (Fg), reacts with convalescent horse serum and protects against lethal S . equi challenge in a small animal model . In the present study, analysis of a panel of 17 purified N- and C-terminal FgBP truncates by ligand affinity blotting and SDS-PAGE revealed that the region required for maximum binding of Fg extended over the first half of the mature protein . The C-terminal two-thirds of this domain is predicted to be alpha-helical coiled-coil and the N-terminal one-third to possess non-coiled-coil single strands . Residues at the extreme N-terminus and within the coiled-coil region are both required for ligand binding . A high incidence of alpha-helical coiled-coil structure also seems to be responsible in part for the aberrant mobility of FgBP on SDS gels . The efficiency with which FgBP binds Fg from different animal species decreases in the order horse > mouse, pig > rat > sheep, dog, bovine, human . Binding to horse Fg is inversely related to temperature over the range 45-4 degrees C and is independent of Ca2+ ions . MS analysis provided corroborative evidence that FgBP is covalently linked to the cell wall peptidoglycan. Microbiology, 2000 May, 146 ( Pt 5), 1179 - 85 Inactivation of the ptsI gene encoding enzyme I of the sugar phosphotransferase system of Streptococcus salivarius: effects on growth and urease expression; Weaver CA et al.; The urease genes of Streptococcus salivarius 57.1 are tightly repressed in cells growing at neutral pH . When cells are cultivated at acidic pH values, the urease genes become derepressed and transcription is enhanced when cells are growing under carbohydrate-excess conditions . Previously, the authors proposed that the bacterial sugar:phosphotransferase system (PTS) modulated the DNA-binding activity by phosphorylation of the urease repressor when carbohydrate was limiting . The purpose of this study was to assess whether enzyme I (EI) of the PTS could be involved in modulating urease expression in response to carbohydrate availability . An EI-deficient strain (ptsI18-3) of S . salivarius 57.1 was constructed by insertional inactivation of the ptsI gene . The mutant had no measurable PTS activity and lacked EI, as assessed by Western analysis . The mutant grew as well as the wild-type strain on the non-PTS sugar lactose, and grew better than the parent when another non-PTS sugar, galactose, was the sole carbohydrate . The mutant was able to grow with glucose as the sole carbohydrate, but displayed a 24 h lag time and had a generation time some threefold longer than strain 57.1 . The mean OD600 attained after 48 h by ptsI18-3 supplied with fructose was 0.16, with no additional growth observed even after 3 d . Urease expression in the wild-type and mutant strains was assessed in continuous chemostat culture . Repression of urease at neutral pH was seen in both strains under all conditions tested . Growth of wild-type cells on limiting concentrations of lactose resulted in very low levels of urease expression compared with growth on PTS sugars . In contrast, under similar conditions, urease expression in ptsI18-3 was restored to levels seen in the parent growing on PTS sugars . Growth under conditions of lactose excess resulted in further derepression of urease, but ptsI18-3 expressed about threefold higher urease activity than 57.1 . The results support a role for EI in urease regulation, but also indicate that additional factors may be important in regulating urease gene expression. Neuropediatrics, 2000 Apr, 31(2), 97 - 9 Cerebellar involvement as a rare complication of pneumococcal meningitis; Drost G et al.; A 4-year old girl with meningitis, caused by streptococcus pneumoniae, developed a subcoma with respiratory insufficiency, followed by a severe cerebellar syndrome . Cerebellar involvement after regaining consciousness consisted of a symmetrical ataxia and mutism . This mutism changed into dysarthria and finally into normal speech . Magnetic resonance imaging revealed lesions in both cerebellar hemispheres, suggesting cerebellitis . She recovered with prompt antibiotic treatment. Indian J Pediatr, 1996 Jul-Aug, 63(4), 549 - 52 Sino-bronchial syndrome in children with asthma; Rajajee S et al.; Thirty children in the age group of 2 to 12 years were brought with a history of recurrent non-seasonal moderate to severe wheezy episodes associated with symptoms of nasal congestion, sneezing and occasional headache . All of them had maxillary or pan sinusitis with 26 having associated right, left or bilateral lower lobe pneumonitis or bronchiectasis . Serum immunoglobulins were normal in 22 and was not done in eight . There was positive (2 to 4+ above negative control) skin test response to dust and dust mite in 15 of the 22 children tested . Throat swabs/sputum or nasal secretions grew B-hemolytic streptococcus or streptococcus pneumoniae in twenty-seven . All the children were put on bactericidal drugs for 6 to 8 weeks and bronchodilators were used when needed . At the end of 6 to 8 weeks follow-up X-ray of sinuses and chest showed significant clearing of the lesions which coincided with marked clinical improvement . Sinus X-ray should be considered in bronchial asthma resistant to medical management since untreated bacterial sinusitis can be an underlying cause of chronic poorly controlled asthma. Acta Paediatr, 2000 Apr, 89(4), 431 - 5 Vulvar symptoms in paediatric and adolescent patients; Piippo S et al.; Vulvovaginal symptoms in children and young adolescents are not yet very well understood, nor is the actual incidence known . This study evaluates the character and possible infectious aetiology of vulvar symptoms of females aged up to 16 y . The signs, symptoms and bacteriological findings of 68 consecutive cases were studied . The study was conducted in the University Hospital of Tampere at a special gynaecological consultation clinic for children and adolescents . Sixty-eight patients were included in the study: 48 girls (71%) were prepubertal, at Tanner stage M1P1, 26 patients were 2-4-y-old and 15 were 5-7-y-old . The duration of symptoms was known for 46 patients: 41% had had symptoms for >1 mo and 20% for >6 mo . Forty-eight patients had abnormal clinical findings on examination and 16 (33%) of them had an infectious aetiology . Streptococcus pyogenes infection was identified in 11 (16%) patients, all of whom had symptoms . Candida was identified in 6 (9%) patients . No infectious aetiology was found among 26 patients who had symptoms and abnormal clinical findings . Vulvovaginal symptoms during childhood are more common among younger children (<7 y) . In 67% of patients no infectious aetiology could be found . Samples for microbiological culture should be taken from symptomatic patients and symptomatic areas . Cultures of Candida and bacteria are necessary but usually sufficient . If a microbiological aetiology is established, treatment can be assigned accordingly . Patients with vulvar symptoms and findings but with an unclear aetiology need support and advice on proper hygiene and can intermittently use mild corticosteroids locally. Acta Paediatr, 2000 Apr, 89(4), 427 - 30 Paediatric infective endocarditis: 19-year experience at a tertiary care hospital in a developing country; Bitar FF et al.; A retrospective study was undertaken to study children who presented with infective endocarditis (IE) to a university teaching hospital in Beirut, Lebanon, between January 1977 and May 1995 . Of 41 patients with IE (24F, 17M), 28 (68%) were diagnosed between 1977 and 1985 . Patients' ages ranged from 3 to 18 y (mean age 11.3+/-2.8 y), and 13 patients were <10 y of age . Clinical presentations included: fever (in 88%), heart failure (in 39%), neurologic findings (in 20%) and embolic phenomena (in 22%) . Nineteen patients (46%) had underlying congenital heart disease (CHD) with tetralogy of Fallot and pulmonary stenosis being the most common . Sixteen patients (39%) had underlying rheumatic heart disease (RHD) . A total of 5 children (12%) with normal cardiac anatomy had IE . One had underlying acquired viral myocarditis with mitral insufficiency . Echocardiography showed vegetations in 60% . Blood cultures were positive in 31 patients (76%) . IE occurred in three patients following cardiac surgery . In one patient it occurred within 2 mo of surgery and in the other two it occurred within 6 mo . Streptococcus viridans and Staphylococcus aureus were the two most commonly isolated bacteria . Overall mortality rate was 29% (not statistically significant between patients presenting between 1977-1985 and 1986-1995; p = 0.17) . There was no statistically significant difference in mortality among the groups (five in the group with CHD, six with RHD and one with structurally normal heart) . This study demonstrates that RHD is an important underlying cause of IE in children in our community . This finding is similar to those in other developing countries and different from those in developed countries . Distribution of pathogens and CHD in our study is comparable to some reports in the literature, except for the higher proportion of patients with underlying pulmonary stenosis . Bacterial endocarditis prophylaxis should be emphasized in patients with RHD or pulmonary stenosis. Indian J Pediatr, 1996 Mar-Apr, 63(2), 204 - 9 Infective endocarditis in infants and children; Bhat AW et al.; Due to changing characteristics of infective endocarditis in the past two decades, we, retrospectively analysed 28 cases of infective endocarditis in children of age less than 15 years at Sher-i-Kashmir Institute of Medical Sciences, Soura, Srinagar from December, 1983 to November, 1993 . The incidence of disease was observed as 1.5 cases/1000 children admitted with a M:F ratio of 2:1 . Three patients were of age less than 2 years (group I) as 25 were above 2 years of age (group II) . The two groups had significant difference in portal of entry of infection, infective microorganisms, echocardiography and prognosis . Congenital heart disease was the commonest underlying cardiac lesion in 24 (85.71%) patients . Portal of entry of infection was apparent in 35.71% only; dental route being more frequent in group II . Streptococcus viridans (in 9 cases) followed by staphylococcus aureus (in 4 cases) were the two common organisms isolated . Patients were treated, for a period of 4-6 weeks with a over all mortality rate of 25% . Factors associated with poor prognosis were age < 2 years, staphylococcal infection ad negative blood cultures . Heart failure resistant to medical therapy was a leading cause of death. Biochemistry, 2000 May 30, 39(21), 6440 - 8 Kinetic and structural characterization of a two-domain streptokinase: dissection of domain functionality; Johnsen LB et al.; The mammalian protease plasminogen can be activated by bacterial activators, the three-domain (alpha, beta, gamma) streptokinases and the one-domain (alpha) staphylokinases . These activators act as plasmin(ogen) cofactors, and the resulting complexes initiate proteolytic activity of host plasminogen which facilitates bacterial colonization of the host organism . We have investigated the kinetic mechanism of the plasminogen activation mediated by a novel two-domain (alpha, beta) streptokinase isolated from Streptococcus uberis (Sk(U)) with specificity toward bovine plasminogen . The interaction between Sk(U) and plasminogen occurred in two steps: (1) rapid association of the proteins and (2) slow transition to the active complex Sk(U)-PgA . The complex Sk(U)-PgA converted plasminogen to plasmin with the following parameters: K(m) < or = 1.5 microM and k(cat) = 0.55 s(-)(1) . The ability of proteolytic fragments of Sk(U) to activate plasminogen was investigated . Only two C-terminal segments (97-261 and 123-261), which both contain the beta-domain (126-261), were shown to be active . They initiated plasminogen activation in complex with plasmin, but not with plasminogen, and thereby exhibited functional similarity to the staphylokinase . The fusion protein His(6)-Sk(U) (i.e., Sk(U) with a small N-terminal tag) acted exclusively in complex with plasmin as well . These observations demonstrate that (1) the N-terminal alpha-domain, including a native N-terminus, was necessary for "virgin" activation of the associated plasminogen in the Sk(U)-PgA complex and (2) the C-terminal beta-domain of Sk(U) is important for recognition of the substrate in the Sk(U)-PgA complex. Curr Microbiol, 2000 Jun, 40(6), 380 - 6 Effects of ammonia and amino acids on the growth and proteolytic activity of three species of rumen bacteria: Prevotella albensis, Butyrivibrio fibrisolvens, and Streptococcus bovis; Sales M et al.; The addition of increasing physiological concentrations of ammonia or amino acids had distinct effects on the growth and proteolytic activity of Streptococcus bovis JB1, Prevotella albensis, and Butyrivibrio fibrisolvens DSM3071 . The growth of S . bovis and B . fibrisolvens was enhanced by NH(3) and AA, and that of P . albensis was reduced compared with a control with protein as the sole source of nitrogen . The proteolytic activity of S . bovis and P . albensis was reduced, but that of B . fibrisolvens was improved . NH(3) seemed to act mainly on the cell-associated fraction of the proteolytic activity, while the action of AA was not specific . In the rumen the proteolytic activity of S . bovis and P . albensis would be optimal at low concentrations of NH(3) or AA (<0.05 and <0.27 g/L respectively) . In contrast, B . fibrisolvens would need higher concentrations (0.5 g/L of NH(3) or 2.7 g/L of AA) . It can be assumed that these bacteria will grow in different ecological niches. Emerg Infect Dis, 2000 May-Jun, 6(3), 283 - 9 High prevalence of penicillin-nonsusceptible Streptococcus pneumoniae at a community hospital in Oklahoma; Moolenaar RL et al.; During 1997, Oklahoma City's Hospital A reported penicillin-nonsusceptible Streptococcus pneumoniae in almost 67% of isolates . To confirm this finding, all Hospital A S . pneumoniae isolates from October 23, 1997, through February 19, 1998, were tested for antibiotic susceptibility and repeat-tested at two other hospital laboratories . Medical records of Hospital A patients with invasive S . pneumoniae infections during 1994 through 1997 were also reviewed . These data were compared with 1998 statewide sentinel hospital surveillance data for invasive S . pneumoniae . Of 48 S . pneumoniae isolates from Hospital A during October 23, 1997, through February 19, 1998, 31 (65%) were penicillin-nonsusceptible S . pneumoniae, and 23 (48%) were highly penicillin resistant . Similar prevalences were confirmed at the other hospital laboratories; however, significant interlaboratory differences were noted in the determination of third-generation cephalosporin susceptibility . During 1994 through 1997, a trend toward increasing penicillin nonsusceptibility (p <0.05) was noted among S . pneumoniae isolates from nursing home patients . During 1998, 85 (30%) of 282 invasive isolates reported to the state surveillance system were penicillin-nonsusceptible S . pneumoniae; 33 (12%) were highly resistant . The increase in resistance observed is notable; the interlaboratory discrepancies are unexplained . To respond, a vaccination program was implemented at Hospital A, and vaccination efforts were initiated at nursing homes. Scand J Infect Dis, 2000, 32(2), 133 - 6 Clinical syndromes associated with adult pneumococcal cellulitis; Parada JP et al.; Streptococcus pneumoniae is an uncommonly recognized etiology of cellulitis in adults . A review of the literature uncovered 30 cases of pneumococcal skin infection in adults . Typically, all patients with pneumococcal cellulitis had an underlying chronic illness, or were immunocompromised by drug or alcohol abuse . Pneumococcal cellulitis presents as two distinctive clinical syndromes: one with extremity involvement in individuals with diabetes and substance abuse; and a second involving the head, neck and upper torso in individuals with systemic lupus erythematosis, nephrotic syndrome and hematologic disorders . For each there are statistically significant associations between the location of pneumococcal cellulitis and underlying clinical disorders . In contrast to other common bacterial etiologies, pneumococcal cellulitis is frequently associated with blood stream invasion, tissue necrosis and suppurative complications . Patients often require surgical interventions and prolonged hospitalizations . A high degree of suspicion and early aggressive management is needed for those presenting with cellulitis characterized by bullae and violaceous color. Int J Syst Evol Microbiol, 2000 Jan, 50 Pt 1, 247 - 9 DNA-DNA reassociation studies of Streptococcus constellatus with unusual 16S rRNA sequences; Jacobs JA et al.; DNA-DNA reassociation studies were performed on previously described 'CI strains', which form an unusual 16S rRNA population within the 'anginosus' group of Streptococcus . The CI strains displayed reassociation values of >70% with the Streptococcus constellatus NCDO 2226T strain, with Tm values <1 degrees C, indicating phylogenetic species identity. J Cereb Blood Flow Metab, 2000 May, 20(5), 834 - 8 Induced hypothermia in experimental pneumococcal meningitis; Angstwurm K et al.; Pneumococcal meningitis resulting from Streptococcus pneumoniae has a death rate of 28% in adults . In severe head injury and stroke, inflammatory changes and intracranial hypertension are improved by induced hypothermia, which also is neuroprotective . We hypothesized that moderate hypothermia ameliorates inflammatory changes in experimental pneumococcal meningitis . Wistar rats were cooled systemically, and meningitis was induced by pneumococcal cell wall components . The increase of regional cerebral blood flow in the meningitis animals was blocked by hypothermia at 6 hours . The reduction of intracranial pressure correlated with temperature . The influx of leukocytes into the cerebrospinal fluid and levels of tumor necrosis factor alpha in the cerebrospinal fluid were decreased . Cooling the animals 2 hours after meningitis induction to 30.5 degrees C was also protective . We conclude that hypothermia is a new adjuvant approach to reduce meningitis-induced changes, in particular intracranial pressure, in the early phase of the disease. Arch Intern Med, 2000 May 22, 160(10), 1399 - 408 Management of community-acquired pneumonia in the era of pneumococcal resistance: a report from the Drug-Resistant Streptococcus pneumoniae Therapeutic Working Group; Heffelfinger JD et al.; OBJECTIVE: To provide recommendations for the management of community-acquired pneumonia and the surveillance of drug-resistant Streptococcus pneumoniae (DRSP) . METHODS: We addressed the following questions: (1) Should pneumococcal resistance to beta-lactam antimicrobial agents influence pneumonia treatment? (2) What are suitable empirical antimicrobial regimens for outpatient treatment of community-acquired pneumonia in the DRSP era? (3) What are suitable empirical antimicrobial regimens for treatment of hospitalized patients with community-acquired pneumonia in the DRSP era? and (4) How should clinical laboratories report antibiotic susceptibility patterns for S pneumoniae, and what drugs should be included in surveillance if community-acquired pneumonia is the syndrome of interest? Experts in the management of pneumonia and the DRSP Therapeutic Working Group, which includes clinicians, academicians, and public health practitioners, met at the Centers for Disease Control and Prevention in March 1998 to discuss the management of pneumonia in the era of DRSP . Published and unpublished data were summarized from the scientific literature and experience of participants . After group presentations and review of background materials, subgroup chairs prepared draft responses, which were discussed as a group . CONCLUSIONS: When implicated in cases of pneumonia, S pneumoniae should be considered susceptible if penicillin minimum inhibitory concentration (MIC) is no greater than 1 microg/mL, of intermediate susceptibility if MIC is 2 microg/ mL, and resistant if MIC is no less than 4 microg/mL . For outpatient treatment of community-acquired pneumonia, suitable empirical oral antimicrobial agents include a macrolide (eg, erythromycin, clarithromycin, azithromycin), doxycycline (or tetracycline) for children aged 8 years or older, or an oral beta-lactam with good activity against pneumococci (eg, cefuroxime axetil, amoxicillin, or a combination of amoxicillin and clavulanate potassium) . Suitable empirical antimicrobial regimens for inpatient pneumonia include an intravenous beta-lactam, such as cefuroxime, ceftriaxone sodium, cefotaxime sodium, or a combination of ampicillin sodium and sulbactam sodium plus a macrolide . New fluoroquinolones with improved activity against S pneumoniae can also be used to treat adults with community-acquired pneumonia . To limit the emergence of fluoroquinolone-resistant strains, the new fluoroquinolones should be limited to adults (1) for whom one of the above regimens has already failed, (2) who are allergic to alternative agents, or (3) who have a documented infection with highly drug-resistant pneumococci (eg, penicillin MIC > or =4 microg/mL) . Vancomycin hydrochloride is not routinely indicated for the treatment of community-acquired pneumonia or pneumonia caused by DRSP. Cutis, 2000 May, 65(5), 318 - 20 Transverse leukonychia with systemic infection; Mautner GH et al.; Transverse white nail bands (leukonychia) have been described in association with systemic illnesses and exposure to toxins, and medications . We describe the occurrence of transverse nail bands in two patients following acute systemic illnesses . In the first case, transverse white nail bands developed in a 30-year-old human immunodeficiency virus-positive man following acute pulmonary tuberculosis . In the second case, transverse white nail bands were noted in an 80-year-old patient following Streptococcus intermedius empyema. Clin Infect Dis, 1999 Apr, 28(4), 873 - 81 Streptococcus pneumoniae spinal infection in Nottingham, United Kingdom: not a rare event; Turner DP et al.; Pneumonia and meningitis are the most frequent manifestations of Streptococcus pneumoniae infection . Spinal infection is considered to be a rarity . Between 1985 and 1997, 8 patients with spinal infection (vertebral osteomyelitis, 3; spinal epidural abscess, 1; both, 4) due to S . pneumoniae were seen at University Hospital (Nottingham, U.K.) . Predisposing factors for pneumococcal infection were documented for five patients and included diabetes mellitus, alcoholism, and corticosteroid therapy . One patient presented with concomitant meningitis and endocarditis . Clinical features of note were prolonged symptoms and a lack of febrile response . S . pneumoniae was isolated from the blood of five patients . Magnetic resonance imaging was used to localize the spinal infection in five patients . Two cases were managed medically . Three patients died after a protracted illness . A literature search revealed 20 other cases of spinal infections due to S . pneumoniae . The salient features of the cases are summarized. Clin Infect Dis, 1999 Apr, 28(4), 730 - 5 Pneumococcal drug resistance: the new "special enemy of old age"; Butler JC et al.; Streptococcus pneumoniae is a leading cause of illness and death among the elderly . The recent emergence of drug-resistant strains has complicated selection of antimicrobial therapy for suspected pneumococcal infections . In some areas of North America, nearly 40% of pneumococcal isolates from the blood or cerebrospinal fluid of persons > or = 65 years old had reduced susceptibility to penicillin . Of all penicillin-resistant infections, >30% occur in persons > or = 65 years old . The increasing prevalence of drug-resistant pneumococci and recent outbreaks of pneumococcal disease in chronic-care facilities emphasize the importance of efforts to prevent these infections in the elderly . Limiting selection for drug-resistant strains through judicious use of antimicrobial drugs and preventing invasive pneumococcal infections through increased use of pneumococcal vaccine form the foundation of these efforts. J Antimicrob Chemother, 2000 Apr, 45 Suppl 1, 107 - 10 Bactericidal activity of gemifloxacin and other quinolones against Streptococcus pneumoniae; Morrissey I et al.; This study compared the bactericidal activity of gemifloxacin (SB-265805) and a panel of test quinolones against two ciprofloxacin-resistant pneumococcal strains (Streptococcus pneumoniae 502226 and 503244) and one ciprofloxacin-sensitive strain (S . pneumoniae C3LN4) . Activities were compared by calculating the bactericidal index of these agents . Gemifloxacin was found to be the most bactericidal quinolone tested against these strains . This finding confirms previous data indicating the superior in vitro activity of gemifloxacin against pneumococci, including ciprofloxacin-resistant strains . Although both ciprofloxacin-resistant strains tested had similar quinolone MICs, they differed considerably in their susceptibility to the bactericidal action of these agents . S . pneumoniae 502226 was more readily killed by quinolones than S . pneumoniae 503244 but, as would be expected, both were less susceptible than the ciprofloxacin-sensitive strain . Of the quinolones tested, trovafloxacin showed disproportionally poor activity against the ciprofloxacin-resistant strains even though potent activity was present against the ciprofloxacin-sensitive strain . These data highlight the importance of assessing quinolone bactericidal activity in addition to the MIC when evaluating new members of this antimicrobial class. J Antimicrob Chemother, 2000 Apr, 45 Suppl 1, 101 - 6 Purification of pneumococcal type II topoisomerases and inhibition by gemifloxacin and other quinolones; Morrissey I et al.; Topoisomerase IV and DNA gyrase were purified from a ciprofloxacin-sensitive Streptococcus pneumoniae strain and from two clinical isolates of S . pneumoniae with high-level resistance to ciprofloxacin by means of a gene cloning method in Escherichia coli . All the quinolones tested (gemifloxacin, trovafloxacin, levofloxacin, ciprofloxacin and grepafloxacin) were able to inhibit topoisomerase IV at lower concentrations than those required for DNA gyrase, suggesting that topoisomerase IV is the primary target in the three pneumococci, in agreement with recently published enzyme data . Gemifloxacin (SB-265805) was found to be the most active agent against topoisomerase IV but, surprisingly, not against DNA gyrase . These findings indicate that the potent in vitro activity of gemifloxacin against S . pneumoniae, including ciprofloxacin-resistant strains, results from a strong affinity for pneumococcal topoisomerase IV. J Antimicrob Chemother, 2000 Apr, 45 Suppl 1, 95 - 9 Efflux and target mutations as quinolone resistance mechanisms in clinical isolates of Streptococcus pneumoniae; Broskey J et al.; The aim of this study was to characterize quinolone resistance mechanisms in strains of Streptococcus pneumoniae with increased MICs of ofloxacin . These strains were also tested for their susceptibility to a battery of quinolone antimicrobial agents, including gemifloxacin . Of the S . pneumoniae isolates used, 27 were susceptible to ofloxacin, 18 intermediate and 48 resistant (ofloxacin MIC <4, 4 and >4 mg/L, respectively) . In general, the ofloxacin-susceptible strains had no amino acid substitutions in GyrA, GyrB, ParC or ParE . Moderate increases in MIC were associated with substitutions in the quinolone resistance-determining region (QRDR) of ParC, while the highest MICs were found for strains that also had substitutions in the QRDR of GyrA . The most common substitutions were Ser79-->Phe in ParC and Ser81-->Phe in GyrA . Other substitutions were identified within the QRDR of ParC and outside the QRDR of ParC and ParE; these did not appear to affect susceptibility . The effects of antimicrobial efflux pumps were studied by determining MICs of a range of quinolones in the presence and absence of reserpine, an inhibitor of Gram-positive efflux pumps . Our results indicated that high-level resistance, caused entirely by efflux, was seen in a minority of ofloxacin-resistant S . pneumoniae strains . Testing the susceptibility of quinolone-resistant strains to gemifloxacin, ciprofloxacin, norfloxacin, ofloxacin and trovafloxacin revealed that gemifloxacin was least affected by this large variety of resistance mechanisms and was the only quinolone with MICs of < or =0.5 mg/L for all strains in this study . These results suggest that gemifloxacin is highly potent against S . pneumoniae and may also be effective against strains resistant to other quinolones. J Antimicrob Chemother, 2000 Apr, 45 Suppl 1, 35 - 9 Activity of gemifloxacin and other new quinolones against Chlamydia pneumoniae: a review; Hammerschlag MR; Quinolones are currently used as empirical therapy for treatment of community-acquired lower respiratory infections as they are effective against a broad range of conventional bacterial and 'atypical' pathogens, including Chlamydia pneumoniae . C . pneumoniae is estimated to be associated with 10-20% of community-acquired pneumonia in adults, and has recently been suggested to play a role in several non-respiratory conditions, including atherosclerosis . The newer, third-generation quinolones have enhanced activity against Gram-positive bacteria, including Streptococcus pneumoniae, and prolonged serum half-lives that permit once-daily dosing . Although gemifloxacin (SB-265805) and other new quinolones have good activity against C . pneumoniae in vitro, practically all published treatment studies have relied on serological diagnosis . Consequently, the microbiological efficacy of these agents in human infection has not been assessed . This paper reviews what is known to date of the in vivo microbiological efficacy of the quinolones against C . pneumoniae, and demonstrates the importance of assessing this parameter when evaluating the clinical utility of these agents in C . pneumoniae infection. J Infect Dis, 2000 May, 181(5), 1842 - 5 Epub 2000 May 15. Immune response to surface protein A of Streptococcus pneumoniae and to high-molecular-weight outer membrane protein A of Moraxella catarrhalis in children with acute otitis media; Samukawa T et al.; The immune response was evaluated in 11 children with Streptococcus pneumoniae and in 9 children with Moraxella catarrhalis otitis media . The age of the children had a range of 4-32 months . The mean IgG, IgM, and IgA antibody responses to surface protein A (PspA) of S . pneumoniae in sera from children at the acute and convalescent stages were 4864 versus 5831 ng/mL, P<.05, 1075 versus 3752 ng/mL, P<.05, and 67 versus 93 ng/mL, nonsignificant (NS), respectively . The mean IgG, IgM, and IgA antibody responses to the high-molecular-weight outer membrane protein (UspA) of M . catarrhalis in sera from children at acute and convalescent stages were 710 versus 935 mg/mL, NS; 1895 versus 2646 ng/mL, NS; and 121 versus 204 ng/mL, P<.05, respectively . These data show that PspA and UspA are immunogenic in children after otitis media. Oper Dent, 1999 Sep-Oct, 24(5), 279 - 85 Evaluation of antibacterial activity of three dentin primers using an in vitro tooth model; Ohmori K et al.; This study compared the antibacterial activities of three dentin primers and investigated a newly designed experimental system using a bovine tooth model method for evaluating antibacterial activity by comparing this method with a conventional disk diffusion method . The antibacterial activities of SA primer in Clearfil Liner Bond, LB primer in Clearfil Liner Bond II, and ED primer in Panavia 21 were evaluated using the conventional disk diffusion method . The 50 microliters aliquot of each primer was applied to three sterilized paper disks, then placed onto Tryptic Soy agar plates already inoculated with Streptococcus mutans . After anaerobic incubation for 48 hours, the diffusion of antibacterial components was determined using the inhibition zone produced around the paper disk . The diameter of the inhibition zones was measured and the average calculated . Standardized cavities (diameter 5.0 mm, depth 3.0 mm) were prepared on the labial surfaces of bovine teeth and inoculated with S mutans (10(6) CFU/microliter) following sterilization by 60Co gamma rays (50 KGy) . The teeth were divided into four groups: SA primer, LB primer, ED primer, and a control group . Except for the control teeth, the cavity preparations were treated with the respective dentin primers, and then firmly sealed with a temporary sealing material . The teeth were placed in bottles containing melted Tryptic Soy agar . Five ml of Tryptic Soy broth was then added to the surface of the hardened Tryptic Soy agar . After 1 week's incubation of the teeth in the bottles at 37 degrees C, the number of bacteria remaining in each cavity was counted, except for eight specimens, which were used for SEM observation . The ED primer showed the widest inhibition zone in the disk diffusion test, which was significantly different from the other primers . Using the bovine tooth model, all dentin primers showed antibacterial activity, with significant differences found among the four groups . The results indicated that ED primer had the strongest antibacterial effect among the three primers. Miss Dent Assoc J, 1999 4th Quarter, 55(4), 38 - 9 The effect of nicotine on growth of Streptococcus mutans; Keene K et al.; There is little information available concerning the effects of nicotine on oral bacteria; and in particular, Streptococcus mutans, an important microbe in the etiology of dental caries . To test the effects of nicotine, Streptococcus mutans were incubated in either 0 or 10(-1)-10(-7) M concentrations of nicotine and then plated onto mitis-salivarius-bacitracin agar . Colonies were counted and treatment groups compared . Both 10(-1) and 10(-2) M nicotine caused total inhibition of bacterial growth, while 10(-3) and 10(-4) M produced significantly more colonies than control . Also, 10(-6) and 10(-7) M nicotine produced a significant reduction in the mean number of colonies . These results suggest a biphasic, dosage-dependent effect of nicotine on the growth of Streptococcus mutans . Since 10(-3) M nicotine has been reported within the saliva of smokeless tobacco users, use of these products could stimulate growth of Streptococcus mutans and possibly place the user at increased risk for dental caries. Compr Ther, 2000 Summer, 26(2), 73 - 81 Group A streptococcus necrotizing fasciitis; File TM Jr et al.; Necrotizing fasciitis due to Group A streptococcus has been observed with increasing frequency over the past decade . Appropriate management requires rapid recognition of this life-threatening infection and expeditious antimicrobial therapy as well as surgical debridement or excision of tissue. J Biol Chem, 2000 May 26, 275(21), 15845 - 50 Biochemical structural analysis of the lantibiotic mutacin II; Krull RE et al.; Mutacin II is a post-translationally modified lantibiotic peptide secreted by Streptococcus mutans T8, which inhibits the energy metabolism of sensitive cells . The deduced amino acid sequence of promutacin II is NRWWQGVVPTVSYECRMNSWQHVFTCC, which is capable of forming three thioether bridges . It was not obvious, however, how the three thioether bridges are organized . To examine the bridging, the cyanogen bromide cleavage products of mutacin II and its variants generated by protein engineering, C15A, C26A, and C15A/C26A, were analyzed by mass spectrometry . Analysis of the wild type molecule and the C15A variant excluded several possibilities and also indicated a high fidelity of formation of the thioether bridges . This allowed us to further resolve the structure by analysis (mass spectrometry and tandem mass spectrometry) of the cyanogen bromide cleavage fragments of the C26A and C15A/C26A mutants . Nuclear magnetic resonance analysis established the presence of one and two dehydrobutyrine residues in mutacin II and the C15A variant, respectively, thus