Vaccine, 2000 Dec 8, 19(9-10), 1159 - 66 Serotype of Streptococcus pneumoniae capsular polysaccharide can modify the Th1/Th2 cytokine profile and IgG subclass response to pneumococal-CRM(197) conjugate vaccines in a murine model; Mawas F et al.; The cellular and antibody responses to type 14 and type 19F Streptococcus pneumoniae capsular polysaccharides (PS) conjugated to CRM(197) were investigated in a mouse model developed for pre-clinical evaluation and quality control of pneumococcal conjugate vaccines . Total IgG antibody and IgG subclasses against PS and the carrier protein for both conjugates were measured in addition to the T cell proliferation and cytokine profiles induced by these conjugates . While unconjugated PS 14 and 19F were at best only weakly immunogenic, both types of conjugate induced strong primary and secondary IgG responses to PS . The responses induced by the two conjugates to the carrier protein were very different; a high level of anti-CRM(197) IgG was induced only by the PS19F conjugate whereas a very weak response was induced by the PS14 conjugate . Interestingly, the IgG subclass distribution was different for the two conjugates; for PS19F conjugate, the IgG response was almost completely of IgG1 subclass with low levels of IgG3 and IgG2a while the response to PS14 conjugate was mainly of the IgG1 and IgG2a subclasses with a low level of IgG3 . The anti-CRM(197) IgG subclass distribution was identical with that to the corresponding conjugated PS . Both types of conjugate induced strong T cell proliferation to recall antigens but induced different patterns of cytokine response in immune spleen cells which were indicative of a Th0 response or a mixture of Th1 and Th2 responses with a bias towards Th2 response in PS19F-CRM(197) immunised mice . In conclusion, PS14- and PS19F-CRM(197) conjugates induced different IgG subclass patterns as a result of inducing different patterns of cytokine response to the carrier protein . This indicates that the serotype of PS can modify the Th1/Th2 response to the carrier protein, which has a direct effect and can predict the IgG subclass of the PS response . Finally, we conclude that this model appears suitable for studying the immunogenicity and immune interaction of different components of multivalent pneumococcal conjugate vaccines and may be applicable to their pre-clinical evaluation and quality control. Microbes Infect, 2000 Nov, 2(14), 1733 - 42 Pathogenesis of neonatal Streptococcus agalactiae infections; Spellerberg B; Streptococcus agalactiae is an important human pathogen causing severe neonatal infections . During the course of infection, S . agalactiae colonizes and invades a number of different host compartments . Bacterial molecules including the polysaccharide capsule, the hemolysin, the C5a peptidase, the C-proteins, the hyaluronate lyase and a number of unknown bacterial components determine the interaction with host tissues . This review summarizes our current knowledge about these interactions. J Clin Microbiol, 2001 Jan, 39(1), 367 - 9 Use of penicillin MICs to predict in vitro activity of other beta-lactam antimicrobial agents against Streptococcus pneumoniae; Brueggemann AB et al.; Linear regression analysis was used to compare penicillin MICs determined with 3,129 recent clinical isolates of Streptococcus pneumoniae to MICs obtained with nine other beta-lactam antimicrobial agents . A strong correlation between penicillin MICs and those obtained with other beta-lactams was demonstrated . It may be possible to test penicillin and use MICs obtained with penicillin to predict MICs of other beta-lactam antimicrobials for Streptococcus pneumoniae. Mol Microbiol, 2001 Jan, 39(2), 512 - 9 The SpeB virulence factor of Streptococcus pyogenes, a multifunctional secreted and cell surface molecule with strepadhesin, laminin-binding and cysteine protease activity; Hytonen J et al.; The interactions between pathogenic bacteria and the host need to be resolved at the molecular level in order to develop novel vaccines and drugs . We have previously identified strepadhesin, a novel glycoprotein-binding activity in Streptococcus pyogenes, which is regulated by Mga, a regulator of streptococcal virulence factors . We have now identified the protein responsible for the strepadhesin activity and find that (i) strepadhesin activity is carried by SpeB, streptococcal pyrogenic exotoxin with cysteine protease activity; (ii) SpeB carries laminin-binding activity of the bacteria; and (iii) SpeB is not only a secreted molecule but also occurs unexpectedly tightly bound to the bacterial cell surface . Thus, in contrast to the previous view of SpeB as mainly an extracellular protease, it is also present as a streptococcal surface molecule with binding activity to laminin and other glycoproteins. Mol Microbiol, 2001 Jan, 39(2), 392 - 406 Group A streptococcal growth phase-associated virulence factor regulation by a novel operon (Fas) with homologies to two-component-type regulators requires a small RNA molecule; Kreikemeyer B et al.; A novel growth phase-associated two-component-type regulator, Fas (fibronectin/fibrinogen binding/haemolytic activity/streptokinase regulator), of Streptococcus pyogenes was identified in the M1 genome sequence, based on homologies to the histidine protein kinase (HPK) and response regulator (RR) part of the Staphylococcus aureus Agr and Streptococcus pneumoniae Com quorum-sensing systems . The fas operon, present in all 12 tested M serotypes, was transcribed as polycystronic message (fasBCA) and contained genes encoding two potential HPKs (FasB and FasC) and one RR (FasA) . Downstream of fasBCA, we identified a small 300 nucleotide monocistronic transcript, designated fasX, that did not appear to encode true peptide sequences . Measurements of luciferase promoter fusions revealed a growth phase-associated transcription of fasBCA and fasX, with peak activities during the late exponential phase . Insertional mutagenesis disrupting fasBCA and fasA led to a phenotype similar to agr-null mutations in S . aureus, with prolonged expression of extracellular matrix protein-binding adhesins and reduced expression of secreted virulence factors such as streptokinase and streptolysin S . In addition, fasX transcription was dependent on the RR FasA; however, deletion mutagenesis of fasX resulted in a similar phenotype to that of the fasBCA or fasA mutants . Complementation of the fasX deletion mutant, with the fasX gene expressed in trans from a plasmid, restored the wild-type fasBCA regulation pattern . This strongly suggested that fasX, a putative non-translated RNA, is the main effector molecule of the fas regulon . However, using spent culture supernatants from wild-type and fas mutant strains, we were not able to show an influence on the logarithmic growth phase expression of fas and dependent genes . Thus, despite structural and functional similarities between fas and agr, to date the fas operon appears not to be involved in group A streptococcal (GAS) quorum-sensing regulation. N Engl J Med, 2000 Dec 28, 343(26), 1917 - 24 Increasing prevalence of multidrug-resistant Streptococcus pneumoniae in the United States; Whitney CG et al.; BACKGROUND: The emergence of drug-resistant strains of bacteria has complicated treatment decisions and may lead to treatment failures . METHODS: We examined data on invasive pneumococcal disease in patients identified from 1995 to 1998 in the Active Bacterial Core Surveillance program of the Centers for Disease Control and Prevention . Pneumococci that had a high level of resistance or had intermediate resistance according to the definitions of the National Committee for Clinical Laboratory Standards were defined as "resistant" for this analysis . RESULTS: During 1998, 4013 cases of invasive Streptococcus pneumoniae disease were reported (23 cases per 100,000 population); isolates were available for 3475 (87 percent) . Overall, 24 percent of isolates from 1998 were resistant to penicillin . The proportion of isolates that were resistant to penicillin was highest in Georgia (33 percent) and Tennessee (35 percent), in children under five years of age (32 percent, vs . 21 percent for persons five or more years of age), and in whites (26 percent, vs . 22 percent for blacks) . Penicillin-resistant isolates were more likely than susceptible isolates to have a high level of resistance to other antimicrobial agents . Serotypes included in the 7-valent conjugate and 23-valent pneumococcal polysaccharide vaccines accounted for 78 percent and 88 percent of penicillin-resistant strains, respectively . Between 1995 and 1998 (during which period 12,045 isolates were collected), the proportion of isolates that were resistant to three or more classes of drugs increased from 9 percent to 14 percent; there also were increases in the proportions of isolates that were resistant to penicillin (from 21 percent to 25 percent), cefotaxime (from 10 percent to 15 percent), meropenem (from 10 percent to 16 percent), erythromycin (from 11 percent to 16 percent), and trimethoprim-sulfamethoxazole (from 25 percent to 29 percent) . The increases in the frequency of resistance to other antimicrobial agents occurred exclusively among penicillin-resistant isolates . CONCLUSIONS: Multidrug-resistant pneumococci are common and are increasing . Because a limited number of serotypes account for most infections with drug-resistant strains, the new conjugate vaccines offer protection against most drug-resistant strains of S . pneumoniae. Curr Microbiol, 2001 Feb, 42(2), 106 - 10 Regulation of H(+)-ATPase synthesis in response to reduced pH in ruminal bacteria; Miwa T et al.; The capacity of ruminal bacteria to regulate H(+)-ATPase synthesis in response to reduced pH was investigated to explain acid tolerance . The activity of H(+)-ATPase in Streptococcus bovis, an acid-tolerant bacterium, was 2.2-fold higher at pH 4.5 than at pH 5.5 . The increase in the amount of H(+)-ATPase protein was similar, suggesting that the increase in H(+)-ATPase activity is owing to the increase in H(+)-ATPase synthesis . The level of atp-mRNA at pH 4.5 was 2.5-fold higher than at pH 5.5, indicating that H(+)-ATPase synthesis is regulated at the transcriptional level, responding to low pH . In Ruminococcus albus, an acid-sensitive bacterium, H(+)-ATPase activity, the amount of H(+)-ATPase protein, and the level of atp-mRNA at pH 7.0 were similar to the values at pH 6.0, the lowest pH permitting growth . This result suggests that R . albus is incapable of enhancing H(+)-ATPase synthesis at low pH . Thus, acid tolerance appeared to be related to the capacity to augment the synthesis of H(+)-ATPase responding to low pH. Eur J Obstet Gynecol Reprod Biol, 2001 Jan, 94(1), 79 - 85 Neonatal group B streptococcal infection . Results of 33 months of universal maternal screening and antibioprophylaxis; Volumenie JL et al.; OBJECTIVE: To assess the efficacy and pitfalls of a protocol of generalized screening for group B Streptococcus (GBS) and intra-partum treatment of all carriers in a clinical setting . DESIGN: A descriptive study and comparison with an historical group . Setting: A tertiary perinatal center . POPULATION: All women attending prenatal care in our center and delivered after 37 weeks were eligible . Study period ranged from January 1994 to September 1996 . Comparison group consisted in deliveries of years 1992 and 1993 . METHODS: Vaginal cultures were performed at 36 weeks on non-selective medium followed by intra-partum treatment of all carrier mothers . Rate of carriage, incidence of neonatal GBS sepsis, influence of risk factors and the reasons for failures were analysed . Comparison was made with an historical group . Statistical analysis was performed using a Chi-square test . RESULTS: There were 5374 term deliveries during the study . 3906 were screened (72.7%) and 559 of them found positive for GBS (14.3%) . We observed 46 early-onset GBS diseases (0.86% of term-births) . 43.5% of infections occurred in babies born from mothers without risks factors at delivery . Negative GBS cultures at sampling accounted for 43.5% of protocol failures . Comparison of the incidence of early-onset GBS disease with the previous two years showed a significant drop (1.45-0.86%, P<0.05) . CONCLUSIONS: Our protocol revealed feasible and effective in reducing the incidence of early-onset GBS disease . Improvements must be studied particularly as to the predictive value of screening cultures. J Bacteriol, 2001 Jan, 183(2), 768 - 72 Competence modulation by the NADH oxidase of Streptococcus pneumoniae involves signal transduction; Echenique JR et al.; Oxygen controls competence development in Streptococcus pneumoniae . Oxygen signaling involves the two-component signal transduction systems CiaRH and ComDE and the competence-stimulating peptide encoded by comC and processed by ComAB . We found that NADH oxidase (Nox) was required for optimal competence . Transcriptional analysis and genetic dissection showed that Nox was involved in post-transcriptional activation of the response regulator ComE and in the transcriptional control of ciaRH and comCDE . Thus, in S . pneumoniae, Nox, with O(2) as its secondary substrate, is part of the O(2)-signaling pathway. Appl Environ Microbiol, 2001 Jan, 67(1), 473 - 4 Pigment production by Streptococcus agalactiae in quasi-defined media; Rosa-Fraile M et al.; A quasi-defined medium that supports the growth of Streptococcus agalactiae as pigmented colonies has been developed . The medium contains starch, a peptic digest of albumin, amino acids, nucleosides, vitamins, and salts . The presence of free cysteine, which could be replaced with other sulphur-containing compounds and to a lesser degree by reducing agents, was required for pigment formation. Appl Environ Microbiol, 2001 Jan, 67(1), 15 - 21 The group I strain of Streptococcus mutans, UA140, produces both the lantibiotic mutacin I and a nonlantibiotic bacteriocin, mutacin IV; Qi F et al.; Strains of Streptococcus mutans produce at least three mutacins, I, II, and III . Mutacin II is a member of subgroup AII in the lantibiotic family of bacteriocins, and mutacins I and III belong to subgroup AI in the lantibiotic family . In this report, we characterize two mutacins produced by UA140, a group I strain of S . mutans . One is identical to the lantibiotic mutacin I produced by strain CH43 (F . Qi et al., Appl . Environ . Microbiol . 66:3221-3229, 2000); the other is a nonlantibiotic bacteriocin, which we named mutacin IV . Mutacin IV belongs to the two-peptide, nonlantibiotic family of bacteriocins produced by gram-positive bacteria . Peptide A, encoded by gene nlmA, is 44 amino acids (aa) in size and has a molecular mass of 4,169 Da; peptide B, encoded by nlmB, is 49 aa in size and has a molecular mass of 4,826 Da . Both peptides derive from prepeptides with glycines at positions -2 and -1 relative to the processing site . Production of mutacins I and IV by UA140 appears to be regulated by different mechanisms under different physiological conditions . The significance of producing two mutacins by one strain under different conditions and the implication of this property in terms of the ecology of S . mutans in the oral cavity are discussed. J Dairy Sci, 2000 Dec, 83(12), 2975 - 9 Efficacies of chlorine dioxide and lodophor teat dips during experimental challenge with Staphylococcus aureus and Streptococcus agalactiae; Boddie RL et al.; We tested two postmilking teat dips for efficacy against Staphylococcus aureus and Streptococcus agalactiae using experimental challenge procedures recommended by the National Mastitis Council . The chlorine dioxide teat dip that contained 0.7% sodium chlorite reduced the number of new intramammary infections (IMI) caused by Staph . aureus by 86.6% and reduced new IMI caused by Strep . agalactiae by 88.4% . The 0.5% iodophor teat dip reduced the number of new IMI caused by Staph . aureus by 92.9% and reduced the number of new IMI caused by Strep . agalactiae by 43.4% . Teat skin and teat end conditions were evaluated before and after the study, and no deleterious effects were noted among dipped quarters compared with undipped control quarters for either teat dip. J Biol Chem, 2001 Apr 13, 276(15), 11844 - 51 Epub 2000 Dec 15. Crystal structure of Streptococcus pneumoniae N-acetylglucosamine-1-phosphate uridyltransferase bound to acetyl-coenzyme A reveals a novel active site architecture; Sulzenbacher G et al.; The bifunctional bacterial enzyme N-acetyl-glucosamine-1-phosphate uridyltransferase (GlmU) catalyzes the two-step formation of UDP-GlcNAc, a fundamental precursor in bacterial cell wall biosynthesis . With the emergence of new resistance mechanisms against beta-lactam and glycopeptide antibiotics, the biosynthetic pathway of UDP-GlcNAc represents an attractive target for drug design of new antibacterial agents . The crystal structures of Streptococcus pneumoniae GlmU in unbound form, in complex with acetyl-coenzyme A (AcCoA) and in complex with both AcCoA and the end product UDP-GlcNAc, have been determined and refined to 2.3, 2.5, and 1.75 A, respectively . The S . pneumoniae GlmU molecule is organized in two separate domains connected via a long alpha-helical linker and associates as a trimer, with the 50-A-long left-handed beta-helix (LbetaH) C-terminal domains packed against each other in a parallel fashion and the C-terminal region extended far away from the LbetaH core and exchanged with the beta-helix from a neighboring subunit in the trimer . AcCoA binding induces the formation of a long and narrow tunnel, enclosed between two adjacent LbetaH domains and the interchanged C-terminal region of the third subunit, giving rise to an original active site architecture at the junction of three subunits. J Comput Aided Mol Des, 2000 Nov, 14(8), 719 - 30 Construction of a full three-dimensional model of the transpeptidase domain of Streptococcus pneumoniae PBP2x starting from its Calpha-atom coordinates; van Hooft PA et al.; A new method is described for generating all-atom protein structures from Calpha-atom information . The method, which combines both local structural trace alignments and comparative side chain modeling with ab initio side chain modeling, makes use of both the virtual-bond and the dipole-path methods . Provided that 3D structures of structurally and functionally related proteins exist, the method presented here is highly suitable for generating all-atom coordinates of partly solved, low-resolution crystal structures . Particularly the active site region can be modeled accurately with this procedure, which enables investigation of the binding modes of different classes of ligands with molecular dynamics simulations . The method is applied to the trace of Streptococcus pneumoniae, in order to construct an all-atom structure of the transpeptidase domain . Since after generation of full coordinates of the transpeptidase domain the structure had been solved to 2.4 A resolution, new X-ray coordinates for the worst modeled loop (residues T370 to M386; 17 out of a total number of 351 residues constituting the transpeptidase domain) were incorporated, as kindly provided by Dr . Dideberg . The structure was relaxed with molecular dynamics simulations and simulated annealing methods . The RMS deviation between the 144 aligned Calpha-atoms and the corresponding ones in the originally solved 3.5 A resolution crystal structure was 0.98 . The 351 Calpha-atoms of the whole transpeptidase domain of the final model showed an RMS deviation of 1.58 . The Ramachandran plot showed that 79.3% of the residues are in the most favored regions, with only 1.0% occurring in disallowed regions . The model presented here can be used to investigate the three-dimensional influences of mutations around the active site of PBP2x. J Chemother, 2000 Nov, 12 Suppl 5, 5 - 14 Teicoplanin Chemistry and Microbiology; Parenti F et al.; The chemistry, microbiology and mode of action of teicoplanin, as well as the mechanism, control and epidemiology of glycopeptide resistance, are discussed in detail . The antibacterial activity of teicoplanin against Gram-positive bacteria, including those expressing resistance to unrelated compounds, is similar to that of vancomycin but with increased potency, particularly against Streptococcus spp and Enterococcus spp . Some strains of coagulase-negative Staphylococcus spp, particularly S . haemolytieus, are less susceptible to teicoplanin than to vancomycin . Teicoplanin is active against vancomycin resistance caused by VanB and VanC, but is not active against VanA resistant strains . The epidemiology of GISA and VISA strains of S . aureus is, as yet, poorly understood with more work necessary to elucidate the sequence of events leading to their evolution . Despite the increasing importance of glycopeptide resistance, teicoplanin has proved its clinical worth and continues to have important potential in the treatment of life-threatening Gram-positive sepsis. J Chemother, 2000 Oct, 12 Suppl 4, 7 - 15 Fluoroquinolones: is there a different mechanism of action and resistance against Streptococcus pneumoniae? Harding I, Simpson I. Starting in the 1950s, study and elucidation of the biochemical mechanisms of resistance to antibiotics led to the understanding of both the biology of bacteria and the mode of action of antibiotics . This holds true for the relationship between Streptococcus pneumoniae and the fluoroquinolones . A new feature in this approach is the availability of the nearly complete chromosome sequence of this major human pathogen . In S . pneumoniae, resistance appears to be mainly due to mutational alterations in the intracellular targets of the fluoroquinolones, the type II DNA topoisomerase gyrase and topoisomerase IV . Both enzymes appear to be the primary targets of the drugs in this species . Mutations in the quinolone resistance-determining region (QRDR) of the gyrA gene or the parC gene, which encode the A subunits of DNA gyrase and topoisomerase IV respectively, confer resistance to single-step mutants . Mutations in gyrB and parE, which encode the B subunits of DNA gyrase and topo IV, respectively, have also been implicated in the fluoroquinolone resistance of certain mutants obtained in vitro . The antibiotics most affected by a single mutation are those for which the mutation occurs in their preferred target e.g . gyrase for sparfloxacin and gatifloxacin and topo IV for ciprofloxacin and levofloxacin . The activity of all fluoroquinolones is decreased further when two or more mutations are present . Because they possess similar targets of action, there is cross resistance, albeit at various degrees depending on the intrinsic activity of the molecule, among fluoroquinolones . This stresses, once more, the misleading concept of breakpoints for clinical categorization . A second mechanism of resistance, enhanced active efflux of hydrophilic quinolones such as norfioxacin and ciprofloxacin, is mediated by the membrane-associated protein, PmrA (pneumococcal multidrug resistance) . This protein is a 12-transmembrane segment proton-dependent multidrug efflux pump of the major facilitator family . The combinatorial approach of bacteria to fluoroquinolone resistance implies that the molecule actually used, as well as a less active member of the class that is more apt to detect resistance mechanisms (e.g . ciprofloxacin), should be tested in vitro. J Chemother, 2000 Oct, 12 Suppl 4, 27 - 31 The use of levofloxacin in the treatment of respiratory tract infection; Shah PM; Increasing resistance among the common respiratory pathogens has encouraged assessment of alternative agents, for example, levofloxacin . Unlike earlier quinolones, levofloxacin has excellent activity against Streptococcus pneumoniae, including strains resistant to penicillin . Clinical trials show levofloxacin to be as effective as cephalosporins in acute exacerbation of chronic bronchitis and as effective as co-amoxiclav, cephalosporins or amoxycillin in community-acquired pneumonia . Levofloxacin is rarely associated with serious adverse events . Nausea, diarrhea, headache and rash are the most common adverse events but are observed less frequently than with some other new quinolones. Am J Vet Res, 2000 Dec, 61(12), 1525 - 9 Pathogenesis of Streptococcus zooepidemicus infection after intratracheal inoculation in llamas; Cebra CK et al.; OBJECTIVES: To test whether generalized Streptococcus zooepidemicus infection could be induced by intratracheal inoculation in llamas and to characterize this infection . ANIMALS: 6 test and 3 control llamas . PROCEDURE: Test llamas received 1 of 3 dosages of S . zooepidemicus by intratracheal injection, whereas control llamas received sterile culture medium . Physical examination variables and results of clinicopathologic analyses of blood, peritoneal fluid, and tracheal wash fluid were compared in test llamas between, before, and during the development of bacteremia and with control llamas . Bacteriologic culture was performed on all collected body fluids and tissue specimens that were collected at necropsy . Tissue specimens that were collected at necropsy were examined histologically . RESULTS: Infection induced fever, anorexia, and signs of depression . Five of 6 infected llamas developed specific signs of inflammation in the thorax or abdomen, bacteremia, neutrophilic leukocytosis with toxic changes and high band neutrophil cell counts, hyperfibrinogenemia, and high peritoneal fluid WBC counts and protein concentrations . On development of bacteremia, llamas had significant decreases in serum iron (from 118+/-25 to 6+/-4 microg/ml) and increases in serum glucose (from 131+/-5 to 253+/-48 mg/dl) concentrations . CONCLUSIONS AND CLINICAL RELEVANCE: Streptococcus zooepidemicus spreads rapidly to other body compartments after intratracheal inoculation in llamas . Fever, anorexia, and signs of depression are the most consistent clinical signs, although other signs are possible . Clinicopathologic analysis of body fluids yields evidence of inflammation . Infection by S . zooepidemicus can be proven by bacteriologic culture of body fluids before death or of tissue specimens after death. Scott Med J, 2000 Oct, 45(5), 153 - 4 Empyema of lung associated with Streptococcus milleri infection; Palaniappan S et al.; Empyema of the lung is a very serious illness which must be detected quickly and treated aggressively . We report an unusual case of empyema of the lung associated with a boating accident while the patient was fishing in a sea loch off the west coast of Scotland. J Am Coll Surg, 2000 Dec, 191(6), 668 - 71 Evaluation of phagocytic function of macrophages in rats after partial splenectomy; Muftuoglu TM et al.; BACKGROUND: Understanding the immunologic properties of the spleen has enabled surgeons to practice splenic conservation surgery . If the upper pole of the spleen can be preserved solely on the upper short gastric vessels, will phagocytic function of macrophages in remnant splenic tissue be affected? The aim of this experimental study was to evaluate the phagocytic function of macrophages in partially resected spleens, with hilar excision preserving the short gastric vessels . STUDY DESIGN: Forty-eight female Wistar albino rats were divided into four groups . Groups 1 and 2 underwent sham operations and groups 3 and 4 underwent partial splenectomy . One milliliter of sodium chloride 0.9% was injected into the abdomen of the rats in groups 1 and 3 and 1 mL of Streptococcus pneumoniae type III as an antigenic stimulus was injected into the abdomen of the rats in groups 2 and 4, 6 weeks after the first operation . Forty-eight hours later, relaparotomy was performed in all animals . India ink was used to determine the capacity of uptake in the splenic phagocytes . To evaluate the phagocytic function of the splenic tissues, histologic examinations were performed according to a macrophage grading system . RESULTS: All spleens in all four groups were stained black after injection of India ink . Phagocytic activity of macrophages was reduced in the partially splenectomized groups, compared with intact spleen groups (group 3 versus group 1; p < 0.0001, group 4 versus group 2; p < 0.0001) . There was a significant difference between groups 1 and 2 according to phagocytic function of macrophages (p = 0.0121) . Also, after Streptococcus pneumoniae type III injection as an antigenic stimulus in group 4, we found that the phagocytic functions of macrophages increased compared with those of the sodium chloride 0.9%-injected group 3 after partial splenectomy (p < 0.0001) . CONCLUSIONS: Phagocytic function of macrophages in rats decreased after partial splenectomy . Nevertheless, the remnant spleens in rats could be stimulated when challenged with an antigenic stimulus. J Chemother, 2000 Oct, 12(5), 406 - 11 Moraxella catarrhalis pneumonia during HIV disease; Manfredi R et al.; To assess the role of Moraxella catarrhalis complications in the setting of HIV disease, and to evaluate their occurrence and outcome according to several epidemiological, clinical, and laboratory parameters, the clinical records of 2123 consecutive HIV-infected patients hospitalized in a 9-year period were retrospectively reviewed, and 4 cases of community-acquired M . catarrhalis pneumonia were identified . Three adult patients had a diagnosis of AIDS and severe concurrent immunodeficiency (with a CD4+ lymphocyte count below 60 cells/microL), while the fourth case involved a child with vertical HIV disease . Leukopenia and neutropenia were never present, but no patient received a potent antiretroviral regimen at the time of disease onset . A concurrent respiratory infection by Streptococcus pneumoniae and Mycobacterium tuberculosis was recognized in 2 of 4 patients . Isolated M . catarrhalis strains were susceptible to all tested antimicrobial compounds (save ampicillin in 2 cases), and appropriate antimicrobial treatment led to clinical and microbiological cure in all described episodes . Only 8 cases of HIV-associated Moraxella spp . disease have been reported to date in seven different literature reports (6 cases of pneumonia, and 1 of septicemia) . According to our experience, M . catarrhalis may be responsible for appreciable morbidity among patients with advanced HIV infection, especially when a low CD4+ cell count or coexisting respiratory disease are present . Clinicians and microbiologists who care for HIV-infected patients should carefully consider the potential pathogenic role of Moraxella spp . organisms. Microbiol Immunol, 2000, 44(10), 863 - 5 Erythromycin resistance genes in Streptococcus pyogenes isolates in Kanagawa, Japan; Murase T et al.; The susceptibility of 224 Streptococcus pyogenes isolates obtained from children in Japan from 1981 to 1997 to treatment with erythromycin was determined by the agar dilution method . A total of 17 isolates belonging to serotype M12T12 were resistant (MICs>1 microg/ml) . Fourteen of the 17 resistant strains obtained from 1982 to 1985 harbored ermB and showed an identical pulsed-field gel electrophoresis pattern, indicating the spread of a single clone . Two ermTR-containing isolates were obtained in 1983 . mefA gene was found in a strain obtained in 1994 in the present study, although this gene is predominantly associated with recent erythromycin resistance among S . pyogenes strains in many countries. Clin Orthop, 2000 Dec, (381), 101 - 5 Limited role of direct exchange arthroplasty in the treatment of infected total hip replacements; Jackson WO et al.; A literature review was performed to determine when direct exchange was most likely to be successful . Twelve reports provided outcome data on infected hip replacements treated with direct exchange . The average duration of followup was 4.8 years, but the range was broad (0.1-17.1 years) . Of the 1,299 infected hip replacements treated with direct exchange, 1,077 (83%) were thought to be free of infection at the last followup . Antibiotic-impregnated bone cement was used in 1,282 of the cases (99%) . There was wide variability in the duration of parenteral antibiotic therapy, ranging from just 24 hours to as many as 8 weeks . In some cases, no oral antibiotics ever were given, whereas in others, oral antibiotics were given for as many as 8 months after parenteral therapy . Factors associated with a successful direct exchange included: (1) absence of wound complications after the initial total hip replacement; (2) good general health of the patient; (3) methicillin-sensitive Staphylococcus epidermidis, Staphylococcus aureus, and Streptococcus species; and (4) an organism that was sensitive to the antibiotic mixed into the bone cement . Factors associated with failure included: (1) polymicrobial infection; (2) gram-negative organisms, especially Pseudomonas species; and (3) certain gram-positive organisms such as methicillin-resistant Staphylococcus epidermidis and Group D Streptococcus . Methicillin-resistant organisms have become more common . Many current revision surgical techniques use cementless implants . Fixation without any cement (no depot antibiotics) may be a contraindication to direct exchange . Additionally, there essentially are no data on the use of bone graft in association with direct exchange . For these reasons, the indications for direct exchange are limited. Salud Publica Mex, 2000 Sep-Oct, 42(5), 413 - 21 {Factors associated with Streptococcus group B colonization in pregnant women in Los Altos, Chiapas}; Ocampo-Torres M et al.; OBJECTIVE: To estimate the prevalence and analyze the factors associated with group B Streptococcus (GBS) colonization in pregnant women of Los Altos, Chiapas, Mexico . MATERIAL AND METHODS: Between February and September 1999, a cross-sectional study was conducted among 910 women who sought delivery care at three public hospitals of San Cristobal de Las Casas, Chiapas . Vaginal and perianal samples were taken for GBS detection by bacteriological culture . Identification of groups and serotypes was performed using latex agglutination . The analysis of factors associated with colonization was done using chi-squared tests and log-linear modeling . RESULTS: GBS colonization was found in 8.6% (95% CI 6.8-10.5) of study subjects . Women with the greatest likelihood of colonization were those with > or = 5 pregnancies, residents of counties with high levels of poverty, working outside the home, and living in homes in which the head of household worked in agriculture (26.8%, OR = 7.25, 95% CI 1.83-28.67) . CONCLUSIONS: In the study area, it is necessary that actions aiming to prevent and control infections by GBS be directed principally at those groups of women with the highest probability of colonization, in order to diminish the perinatal transmission of GBS. Chemotherapy, 2001 Jan-Feb, 47(1), 39 - 42 In vitro development of resistance to three quinolones in Streptococcus pneumoniae; Rodriguez JC et al.; We studied the in vitro development of resistance to ciprofloxacin, trovafloxacin and moxifloxacin in 5 strains of Streptococcus pneumoniae resistant to penicillin . We detected the great ease of in vitro development of resistance in the case of ciprofloxacin and the much reduced capacity of moxifloxacin to generate resistance (only 1 strain) . Trovafloxacin generated resistance, but more slowly than ciprofloxacin . We consider that study of the capacity to generate resistance should be one of the points to consider when deciding on their large-scale use in respiratory infections, but comparative studies between in vitro and in vivo models should be carried out so as to determine the clinical repercussion of these phenomena . Caries Res, 2001 Jan-Feb, 35(1), 67 - 74 Properties of Streptococcus sanguinis glucans formed under various conditions; Kopec LK et al.; The aim of our study was to determine whether the structure of glucans formed by glucosyltransferase from Streptococcus sanguinis (GtfSs) on a surface differ from those formed in solution and to explore the effects of antiserum to Gtfs, control normal rabbit serum, starch hydrolysates (STH) and dextran on S . sanguinis (GtfSs) glucan . Linkage analyses showed that solution-formed glucans are predominantly alpha-1,6-linked and have a small amount of alpha-1,3-linked glucose . Surface-formed glucans have enhanced susceptibility to mutanase . Solution- and surface-formed glucans made in the presence or absence of sera, STH, and dextran contain linkages which differ in both amount and type from control glucans . The GtfSs enzyme in solution exposed to antiserum behaves as if it is adsorbed to a surface . Binding of Streptococcus mutans GS-5 and Actinomyces viscosus OMZ105E (Ny1) to S . sanguinis glucan differs if the glucan is formed in the presence of antiserum . The information could help to define the role of glucans in the formation of pellicle, colonization of tooth surfaces and the accumulation of dental plaque. J Mol Biol, 2001 Jan 12, 305(2), 279 - 89 Crystal structures of Streptococcus pneumoniae N-acetylglucosamine-1-phosphate uridyltransferase, GlmU, in apo form at 2.33 A resolution and in complex with UDP-N-acetylglucosamine and Mg(2+) at 1.96 A resolution; Kostrewa D et al.; N-Acetylglucosamine-1-phosphate uridyltransferase (GlmU) is an essential bacterial enzyme with both an acetyltransferase and a uridyltransferase activity which have been mapped to the C-terminal and N-terminal domains, respectively . GlmU performs the last two steps in the synthesis of UDP-N-acetylglucosamine (UDP-GlcNAc), which is an essential precursor in both the peptidoglycan and the lipopolysaccharide metabolic pathways . GlmU is therefore an attractive target for potential antibiotics . Knowledge of its three-dimensional structure would provide a basis for rational drug design . We have determined the crystal structures of Streptococcus pneumoniae GlmU (SpGlmU) in apo form at 2.33 A resolution, and in complex with UDP-N-acetyl glucosamine and the essential co-factor Mg(2+) at 1.96 A resolution . The protein structure consists of an N-terminal domain with an alpha/beta-fold, containing the uridyltransferase active site, and a C-terminal domain with a long left-handed beta-sheet helix (LbetaH) domain . An insertion loop containing the highly conserved sequence motif Asn-Tyr-Asp-Gly protrudes from the left-handed beta-sheet helix domain . In the crystal, S . pneumoniae GlmU forms exact trimers, mainly through contacts between left-handed beta-sheet helix domains . UDP-N-acetylglucosamine and Mg(2+) are bound at the uridyltransferase active site, which is in a closed form . We propose a uridyltransferase mechanism in which the activation energy of the double negatively charged phosphorane transition state is lowered by charge compensation of Mg(2+) and the side-chain of Lys22 . Mol Microbiol, 2001 Jan, 39(1), 126 - 35 Differential fluorescence induction reveals Streptococcus pneumoniae loci regulated by competence stimulatory peptide; Bartilson M et al.; Differential fluorescence induction (DFI) in Streptococcus pneumoniae was used as a method for the discovery of genes activated in specific growth environments . Competence stimulatory peptide (CSP) was used as the model inducing system to identify differentially expressed genes . To identify CSP-induced promoters, a plasmid library was constructed by inserting random pieces of S . pneumoniae chromosomal DNA upstream of the promoterless gfpmut2 gene in an Escherichia coli/S . pneumoniae shuttle vector . S . pneumoniae carrying the library were induced with CSP and enriched for green fluorescent protein (GFP)-expressing bacteria using fluorescence-activated cell sorting . A total of 886 fluorescent clones was screened, and 12 differentially activated promoter elements were identified . Sequence analysis of these clones revealed that three were associated with novel competence loci, one of which we show is essential for DNA uptake, and six are known CSP-inducible promoters . We also explored whether competence proteins have a role in virulence and found that mutations in three CSP-inducible genes resulted in attenuated virulence phenotypes in either of two murine infection models . These results demonstrate the utility of DFI as a method for identifying differentially expressed genes in S . pneumoniae and the potential utility of applying DFI to other Gram-positive bacteria. J Struct Biol, 2000 Oct, 132(1), 72 - 81 Structure and molecular mechanism of a functional form of pneumolysin: a cholesterol-dependent cytolysin from Streptococcus pneumoniae; Kelly SJ et al.; One of the key steps in understanding human disease arising from gram-positive bacteria lies in the mechanisms of the cholesterol-dependent cytolysins (CDCs) . Pneumolysin (PLY), a CDC from Streptococcus pneumoniae, is of special importance due to the severe impacts of pneumococcal infections on mortality and morbidity worldwide . We have overexpressed, purified, and characterized PLY in its fully functional complex form with the enzyme bound to its receptor activator on target cells, cholesterol . The circular dichroism studies of PLY in solution with an excess of cholesterol show a change in the far UV spectrum consistent with a decrease in the beta-sheet and an increase in the random coil structures of the enzyme . Pore formation in membranes leading to cell lysis is the functional target for this cytolysin . The sedimentation velocity and equilibrium analyses of the cholesterol-bound enzyme show hydrodynamic properties different from those of the cholesterol-free form . The soluble form of the cholesterol-free enzyme exists in solution as a mixture of monomers and dimers, whereas the cholesterol-bound form exists only as a monomer . A mechanism of formation of PLY pores in the lipid bilayer of the target cells is discussed . Antimicrob Agents Chemother, 2001 Jan, 45(1), 342 - 4 Identification of an erm(A) erythromycin resistance methylase gene in Streptococcus pneumoniae isolated in Greece; Syrogiannopoulos GA et al.; In a serotype 11A clone of erythromycin-resistant pneumococci isolated from young Greek carriers, we identified the nucleotide sequence of erm(A), a methylase gene previously described as erm(TR) in Streptococcus pyogenes . The erm(A) pneumococci were resistant to 14- and 15-member macrolides, inducibly resistant to clindamycin, and susceptible to streptogramin B . To our knowledge, this is the first identification of resistance to erythromycin in S . pneumoniae attributed solely to the carriage of the erm(A) gene. Antimicrob Agents Chemother, 2001 Jan, 45(1), 339 - 41 Prevalence and mechanisms of macrolide resistance in Streptococcus pyogenes in Santiago, Chile; Palavecino EL et al.; Thirty-two macrolide-resistant Streptococcus pyogenes isolates were found among 594 clinical isolates collected from 1990 to 1998 in Santiago, Chile, for an overall prevalence of 7.2% . Among the 32 resistant isolates, 28 (87.5%) presented the M phenotype and 4 (12 . 5%) presented the MLS(B) phenotype . Serotyping and pulsed-field gel electrophoresis analysis showed genetic diversity among the resistant isolates. Antimicrob Agents Chemother, 2001 Jan, 45(1), 319 - 23 Mutation in 23S rRNA responsible for resistance to 16-membered macrolides and streptogramins in Streptococcus pneumoniae; Depardieu F et al.; Streptococcus pneumoniae clinical isolate BM4455 was resistant to 16-membered macrolides and to streptogramins . This unusual resistance phenotype was due to an A(2062)C (Escherichia coli numbering) mutation in domain V of the four copies of 23S rRNA. Antimicrob Agents Chemother, 2001 Jan, 45(1), 316 - 8 Effective combination therapy for invasive pneumococcal pneumonia with ampicillin and intravenous immunoglobulins in a mouse model; De Hennezel L et al.; Intranasal immunotherapy for Streptococcus pneumoniae invasive pneumonia with polyvalent immunoglobulins (IVIG) was effective in mice against pneumonia but failed to prevent bacteremia . The combination of subcurative doses of IVIG and of ampicillin was fully protective . Such an approach, successfully applied in the preantibiotic era, offers new perspectives for modern therapies. Antimicrob Agents Chemother, 2001 Jan, 45(1), 252 - 62 Kinetic study of the inflammatory response in Streptococcus pneumoniae experimental pneumonia treated with the ketolide HMR 3004; Duong M et al.; Patients still die from Streptococcus pneumoniae pneumonia after initiation of antibiotic therapy, when tissues are sterile and the pneumonia is clearing . There is growing evidence that overwhelming inflammation resulting from toxin release contributes to tissue injury, shock, and death . Monitoring host response may help us understand the consequences of antibiotic therapy for the inflammatory processes that occur in bacterial pneumonia . HMR 3004 is a ketolide that displays excellent in vitro activity against S . pneumoniae . In the present experiment, we investigated the chronology of inflammatory events that occur during pneumococcal pneumonia in mice treated with HMR 3004 . Infection of mice with 10(7) CFU of living S . pneumoniae resulted in 100% mortality within 5 days . HMR 3004 given at 12.5 mg/kg of body weight/dose twice daily from 48 h postinfection achieved complete bacterial clearance from lungs and blood within 36 h and ensured survival of mice . Recruitment of neutrophils and monocytes from blood to lungs was significantly reduced, and nitric oxide release was totally prevented . Interleukin-6 secretion in lungs and blood became rapidly undetectable after initiation of therapy . Histological examination of lung tissue showed protection of interstitium against edema . By controlling bacterial invasion, HMR 3004 led to rapid and profound modifications of the host response in lungs, which may protect mice from deleterious inflammatory reactions. Antimicrob Agents Chemother, 2001 Jan, 45(1), 166 - 9 Effect of xylitol on growth of Streptococcus pneumoniae in the presence of fructose and sorbitol; Tapiainen T et al.; Xylitol is effective in preventing acute otitis media by inhibiting the growth of Streptococcus pneumoniae . To clarify this inhibition we used fructose, which is known to block similar growth inhibition observed in Streptococcus mutans . In addition, we evaluated the efficacy of sorbitol in inhibiting the growth of pneumococci, as sorbitol is widely used for indications similar to those for which xylitol is used . The addition of 5% xylitol to the growth medium resulted in marked growth inhibition, an effect which was totally eliminated in the presence of 1, 2.5, or 5% fructose but not in the presence of 1 or 5% glucose, 1% galactose, or 1% sucrose . This finding implies that xylitol-induced inhibition of pneumococcal growth is mediated via the fructose phosphotransferase system in a way similar to that in which mutans group streptococcal growth is inhibited . The addition of sorbitol at concentrations of 1, 2.5, or 5% to the growth medium did not affect the growth of pneumococci and neither inhibited nor enhanced the xylitol-induced growth impairment . Thus, it seems that xylitol is the only commercially used sugar substitute proven to have an antimicrobial effect on pneumococci. J Immunol, 2000 Dec 15, 165(12), 6840 - 8 B7 requirements for primary and secondary protein- and polysaccharide-specific Ig isotype responses to Streptococcus pneumoniae; Wu ZQ et al.; The requirements for B7 costimulation during an in vivo humoral response to an intact extracellular bacteria have not been reported . In this study we immunized mice with Streptococcus pneumoniae (R36A) to determine the B7 requirements for induction of Ig, specific for two determinants on R36A, the phosphorylcholine (PC) determinant of C-polysaccharide and pneumococcal surface protein A (PspA) . We show that the primary anti-PspA response, the development of PspA-specific memory, and the induction of the secondary anti-PspA response in primed mice were completely dependent upon B7 costimulation . Of note, costimulation was required only briefly after the secondary immunization compared with after the primary immunization for optimal induction of Ig . Blockade of B7 costimulation at the time of secondary immunization also completely abrogated the established state of memory, but did not induce tolerance . In contrast to the anti-PspA response, the primary anti-PC response involved only a very short period of B7 costimulation . Whereas B7-2 alone was required for induction of the primary anti-PspA and anti-PC responses, a redundant role for B7-1 and B7-2 was noted for the PspA-specific secondary response . CTLA4Ig blocked both the anti-PC and anti-PspA responses equally well over a wide range of bacterial doses . These studies demonstrate a critical, but variable, role for B7-dependent costimulation during an Ig response to an extracellular bacteria. Infect Immun, 2001 Jan, 69(1), 622 - 5 Characterization of the domain of fibronectin-binding protein I of Streptococcus pyogenes responsible for elicitation of a protective immune response; Schulze K et al.; Fibronectin-binding protein I (SfbI) represents a major adhesin of Streptococcus pyogenes . Mice were intranasally immunized with recombinant proteins spanning different portions of SfbI to identify the minimal fragment able to elicit a protective response against a lethal challenge with S . pyogenes . The strongest cellular responses and the highest levels of antigen-specific secretory immunoglobulin A (IgA) were detected in mice immunized with the fibronectin-binding region of SfbI . In contrast, animals vaccinated with a polypeptide spanning the aromatic and proline-rich regions showed the highest titers and fastest IgG response in serum . Vaccination with either SfbI without a membrane anchor and signal peptide or a polypeptide encompassing its fibronectin-binding regions resulted in efficient protection against heterologous challenge (60% and 80%, respectively), whereas the use of a polypeptide lacking this region conferred marginal protection (10%) with respect to the control group (0%) . These results demonstrate that the fibronectin-binding region of SfbI is a promising candidate antigen for developing anti-S . pyogenes vaccines. Infect Immun, 2001 Jan, 69(1), 602 - 6 Effect of influenza A virus infection on nasopharyngeal colonization and otitis media induced by transparent or opaque phenotype variants of Streptococcus pneumoniae in the chinchilla model; Tong HH et al.; Phase variation in the colonial opacity of Streptococcus pneumoniae has been implicated as a factor in bacterial adherence, colonization, and invasion in the pathogenesis of pneumococcal disease . Additionally, the synergistic effects of influenza A virus and S . pneumoniae in the development of otitis media (OM) have been reported . This study examined the ability of opaque or transparent S . pneumoniae from the same strain in combination with an antecedent influenza A virus infection to colonize the nasopharynx and invade the middle ear in the chinchilla model . Our data indicated that there was no significant difference in the level of nasopharyngeal colonization and induction of OM between the opaque and transparent variants unless there was a prior challenge with influenza A virus . Subsequent to influenza A virus infection, there was a significant difference between the variants in the ability to colonize and persist in the nasopharynx and middle ear . The concentrations of the opaque variant in nasopharyngeal-lavage samples and middle-ear fluid remained consistently higher than those of the transparent variant for 10 days postinoculation . Data from this study indicate that the effects of influenza A virus on the pathogenesis of experimental S . pneumoniae-induced OM differ depending on the opacity phenotype involved. Infect Immun, 2001 Jan, 69(1), 426 - 34 Role of genetic resistance in invasive pneumococcal infection: identification and study of susceptibility and resistance in inbred mouse strains; Gingles NA et al.; From a panel of nine inbred mice strains intranasally infected with Streptococcus pneumoniae type 2 strain, BALB/c mice were resistant and CBA/Ca and SJL mice were susceptible to infection . Further investigation revealed that BALB/c mice were able to prevent proliferation of pneumococci in the lungs and blood, whereas CBA/Ca mice showed no bacterial clearance . Rapidly increasing numbers of bacteria in the blood was a feature of CBA/Ca but not BALB/c mice . In the lungs, BALB/c mice recruited significantly more neutrophils than CBA/Ca mice at 12 and 24 h postinfection . Inflammatory lesions in BALB/c mice were visible much earlier than in CBA/Ca mice, and there was a greater cellular infiltration into the lung tissue of BALB/c mice at the earlier time points . Our data suggest that resistance or susceptibility to intranasal pneumococci may have an association with recruitment and/or function of neutrophils. Infect Immun, 2001 Jan, 69(1), 392 - 9 Identification and disruption of two discrete loci encoding hyaluronic acid capsule biosynthesis genes hasA, hasB, and hasC in Streptococcus uberis; Ward PN et al.; The hyaluronic acid capsule of Streptococcus uberis has been implicated in conferring resistance to phagocytosis by bovine neutrophils . Construction of a bank of random insertion mutants of S . uberis (strain 0140J) was achieved using the pGh9::ISS1 mutagenesis system (22) . Phenotypic screening of approximately 5,000 clones enabled the isolation of 11 acapsular mutants . Southern hybridization indicated that two mutants carried a lesion within a group of genes similar to those involved in the assembly of the hyaluronic acid capsule found in the group A Streptococcus (GAS) has operon . The DNA sequence flanking the points of insertion confirmed the presence of homologues of GAS hasA and hasB in S . uberis . The DNA sequence flanking the ISS1 insertion in another mutant identified a homologue of hasC in S . uberis . The GAS hasABC operon structure was not conserved in S . uberis, and two discrete loci comprising homologues of either hasAB or hasC were identified . Disruption of S . uberis hasA or hasC resulted in the complete cessation of hyaluronic acid capsule production . Correspondingly, these mutants were found to have lost their resistance to phagocytosis by bovine neutrophils . The bactericidal action of bovine neutrophils on S . uberis 0140J was shown unequivocally to depend upon the capsule status of the bacterium. Infect Immun, 2001 Jan, 69(1), 336 - 44 Avidity, potency, and cross-reactivity of monoclonal antibodies to pneumococcal capsular polysaccharide serotype 6B; Sun Y et al.; Many pneumococcal capsular polysaccharides (PSs) are similar in structure, and a pneumococcal antibody often binds to all of the PSs with a similar structure . Yet, these cross-reactive antibodies may bind to the structurally related pneumococcal capsular PSs with an avidity too low to be effective . If memory B cells producing such weakly cross-reactive antibodies are elicited with pneumococcal conjugate vaccines, the memory cells for low-avidity antibodies could compromise the subsequent immune responses to the cross-reactive PS (original antigenic sin) . To investigate these issues, we produced 14 hybridomas secreting monoclonal antibodies (MAbs) to the capsular PS of Streptococcus pneumoniae serotype 6B by immunizing BALB/c mice with antigens containing 6B PS and studied their epitope, avidity, in vitro opsonizing capacity, in vivo protective capacity, and "antigen binding titer" by enzyme-linked immunosorbent assay (ELISA) of 6A and 6B capsular PSs . Six MAbs bound to the non-cross-reactive 6B-specific epitope, and seven MAbs bound to the cross-reactive epitope present in both 6A and 6B PSs One MAb (Hyp6BM6) revealed a novel epitope . This epitope was found on 6A PS in solution, but not on 6A PS adsorbed onto the plastic surface of the ELISA plates . The avidity of the MAb for 6A or 6B PS ranged from 7.8 x 10(6) M(-1) to 4.1 x 10(11) M(-1) . No MAbs were weakly cross-reactive, since none of the cross-reactive MAbs showed any tendency toward having less avidity to 6A PS (the cross-reactive PS) than to 6B PS . Avidity influenced the results of several antibody assays . When all of the hybridomas were examined, avidity strongly correlated with the titer of a unit amount of MAb to bind antigen-coated ELISA plates (r = 0.91) or to opsonize pneumococci in vitro (r = -0.85) . Because both assay results are avidity dependent, the ELISA and the opsonization assay results were strongly correlated (r = 0.91), regardless of avidity . Avidity also correlated with the potency of a MAb to passively protect mice against pneumococcal infections . When only the immunoglobulin G hybridomas were examined, little increase in opsonizing capacity and in vivo protective potency was observed above 10(9) M(-1) . Taken together, an ELISA measuring antigen binding titer may be an adequate measure of the protective immunity induced with pneumococcal vaccines, and the absence of a partially cross-reactive MAb suggests that antigenic sin may not be significant in responses to vaccines against the S . pneumoniae 6B serotype. Infect Immun, 2001 Jan, 69(1), 297 - 306 Group B Streptococcus capsular polysaccharide-cholera toxin B subunit conjugate vaccines prepared by different methods for intranasal immunization; Shen X et al.; Group B Streptococcus (GBS) type III capsular polysaccharide (CPS III) was conjugated to recombinant cholera toxin B subunit (rCTB) using three different methods which employed (i) cystamine and N-succinimidyl-3-(2-pyridyldithio)propionate (SPDP), (ii) carbodiimide with adipic acid dihydrazide (ADH) as a spacer, or (iii) reductive amination (RA) . The CPS III-rCTB conjugates were divided into large- and small-molecular-weight (M(r)) fractions, and the immunogenicities of the different preparations after intranasal (i.n.) immunization were studied in mice . Both large- and small-M(r) conjugates of CPS III-rCTB(RA) or CPS III-rCTB(ADH) induced high, almost comparable levels of CPS-specific immunoglobulin G (IgG) in serum, lungs, and vagina that were generally superior to those obtained with CPS III-rCTB(SPDP) conjugates or a CPS III and rCTB mixture . However, the smaller-M(r) conjugates of CPS III-rCTB(RA) or CPS III-rCTB(ADH) in most cases elicited a lower anti-CPS IgA immune response than the large-M(r) conjugates, and the highest anti-CPS IgA titers in both tissues and serum were obtained with the large-M(r) CPS III-rCTB(RA) conjugate . Serum IgG anti-CPS titers induced by the CPS III-rCTB(RA) conjugate had high levels of specific IgG1, IgG2a, IgG2b, and IgG3 antibodies . Based on the effectiveness of RA for coupling CPS III to rCTB, RA was also tested for conjugating GBS CPS Ia with rCTB . As for the CPS III-rCTB conjugates, the immunogenicity of CPS Ia was greatly increased by conjugation to rCTB . Intranasal immunization with a combination of CPS Ia-rCTB and CPS III-rCTB conjugates was shown to induce anti-CPS Ia and III immune responses in serum and lungs that were fully comparable with the responses to immunization with the monovalent CPS Ia-rCTB or CPS III-rCTB conjugates . These results suggest that the GBS CPS III-rCTB and CPS Ia-rCTB conjugates prepared by the RA method may be used in bivalent and possibly also in multivalent mucosal GBS conjugate vaccines. Infect Immun, 2001 Jan, 69(1), 75 - 80 Inactivation of the srtA gene in Streptococcus gordonii inhibits cell wall anchoring of surface proteins and decreases in vitro and in vivo adhesion; Bolken TC et al.; The srtA gene product, SrtA, has been shown to be required for cell wall anchoring of protein A as well as virulence in the pathogenic bacterium Staphylococcus aureus . There are five major mechanisms for displaying proteins at the surface of gram-positive bacteria (P . Cossart and R . Jonquieres, Proc . Natl . Acad . Sci . USA 97:5013-5015, 2000) . However, since many of the known surface proteins of gram-positive bacteria are believed to be exported and anchored via the sortase pathway, it was of interest to determine if srtA plays a similar role in other gram-positive bacteria . To that end, the srtA gene in the human oral commensal organism Streptococcus gordonii was insertionally inactivated . The srtA mutant S . gordonii exhibited a marked reduction in quantity of a specific anchored surface protein . Furthermore, the srtA mutant had reduced binding to immobilized human fibronectin and had a decreased ability to colonize the oral mucosa of mice . Taken together, these results suggest that the activity of SrtA plays an important role in the biology of nonpathogenic as well as pathogenic gram-positive cocci. Vet Microbiol, 2001 Jan 5, 78(1), 29 - 37 Influence of ampicillin, ceftiofur, attenuated live PRRSV vaccine, and reduced dose Streptococcus suis exposure on disease associated with PRRSV and S . suis coinfection; Schmitt CS et al.; The objective of this research was to evaluate the efficacy of two antimicrobials (ampicillin and ceftiofur), a modified-live porcine reproductive and respiratory syndrome virus (PRRSV) vaccine, and low dose exposure to Streptococcus suis on disease associated with PRRSV/S . suis coinfection . Fifty-six, crossbred, PRRSV-free pigs were weaned at 10-12 days of age and randomly assigned to five treatment groups . All pigs were inoculated with 2ml of 10(6.4) TCID50/ml of high virulence PRRSV isolate VR-2385 intranasally at 29-31 days of age (day 0 of the study) followed 7 days later by intranasal inoculation with 2ml of 10(8.9)colony forming units(CFU)/ml S . suis type 2 isolate ISU VDL #40634/94 . Pigs in group 1 (n=10) served as untreated infected positive controls . Pigs in group 2 (n=12) were treated with 5.0 mg/kg ceftiofur hydrochloride intramuscularly (IM) on days 8, 11, and 14 . Pigs in group 3 (n=11) were treated with 11 mg/kg ampicillin IM on days 8-10 . Pigs in group 4 (n=12) were vaccinated 14 days prior to PRRSV challenge with a commercial modified-live PRRSV vaccine . Pigs in group 5 (n=11) were exposed to a 1:100 dilution of the S . suis challenge inoculum 19 days prior to S . suis challenge . Mortality was 80, 25, 82, 83, and 36% in groups 1-5, respectively . The reduced dose S . suis exposure had some residual virulence, evidenced by S . suis induced meningitis in two pigs after exposure . Treatment with ceftiofur hydrochloride and reduced dose exposure to S . suis were the only treatments which significantly (P<0.05) reduced mortality associated with PRRSV/S . suis coinfection, significantly (P<0.05) reduced recovery of S . suis from tissues at necropsy, and significantly (P<0.05) reduced the severity of gross lung lesions. Toxicology, 2000 Nov 23, 154(1-3), 85 - 101 Carbon tetrachloride is immunosuppressive and decreases host resistance to Listeria monocytogenes and Streptococcus pneumoniae in female B6C3F1 mice; Guo TL et al.; Carbon tetrachloride (CCl(4)) is an environmental contaminant that has been detected in ambient air, seawater, surface-water and snow . The immunotoxic potential of CCl(4) was evaluated in female B6C3F1 mice . The animals were administered with CCl(4) daily for 14 days at doses of 50, 100, 500 or 1000 mg/kg body weight by gavage with corn oil as a vehicle . Exposure to CCl(4) resulted in an increase of liver weight but not the body weight and the weights of brain, spleen, lungs, thymus and kidneys . Exposure to CCl(4) produced minimal effect on differential hematological parameters; however, it produced a significant increase in serum glutamic-pyruvic transaminase (SGPT) levels in all dose groups while other serum chemistries showed sporadic increases, primarily at the dose level of 1000 mg/kg . Exposure to CCl(4) produced a decreased humoral immune response; the IgM antibody forming cell (AFC) response to sheep red blood cells (sRBC) was suppressed with the maximal decrease (45%) observed at the dose level of 1000 mg/kg . The IgM serum titer to sRBC was also reduced with a maximal decrease (54%) observed at the dose level of 500 mg/kg . Although exposure to CCl(4) had no effects on the mixed leukocyte response (MLR), cytotoxic T lymphocyte activity and natural killer (NK) cell activity, a decrease in both the absolute number and the percentage of CD4(+)CD8(-) at the dose level of 500 mg/kg was observed . The functional activity of the mononuclear phagocyte system was compromised as reflected by a decrease in the vascular clearance of (51)Cr-sRBC and a decrease in the uptake of (51)Cr-sRBC by the liver . Finally, in the two host resistance models evaluated, exposure to CCl(4) decreased host resistance to both Streptococcus pneumoniae and Listeria monocytogenes with greater susceptibility to the latter . Overall, these studies demonstrate that CCl(4) was immunosuppressive in female B6C3F1 mice. Enzyme Microb Technol, 2000 Dec, 27(10), 784 - 788 Data and knowledge based experimental design for fermentation process optimization; Berkholz R et al.; A novel method for the sequential experimental design in order to optimize fed-batch fermentations was applied to a hyaluronidase fermentation by Streptococcus agalactiae . A Lambda-optimal design was introduced to minimize the model parameter estimation error and to maximize the performance of the fermentation process . The method employs hybrid models that contain mechanistic, fuzzy and neural network components. J Oral Maxillofac Surg, 2000 Dec, 58(12), 1347 - 52; discussion 1353 Cervical necrotizing fasciitis of odontogenic origin: a report of 11 cases; Tung-Yiu W et al.; PURPOSE: Although most cases of cervical necrotizing fasciitis (CNF) are odontogenic in origin, reports of this disease in the dental literature are sparse . The purpose of this study was to review the cases treated on our service, and to analyze the features of this disease and the responses to management, to supplement the understanding of this relatively rare and life-threatening disease . PATIENTS AND METHODS: All cases of infection admitted to the OMS service in a period of 10.5 years were studied retrospectively . The diagnosis of CNF was established by the findings on surgical exploration and histologic examination . The patients' age, sex, medical status, causes of the infection, bacteriology, computed tomography scan findings, surgical interventions, complications, survival, and other clinical parameters were reviewed . RESULTS: A total of 422 cases of infection were admitted, and 11 cases of cervical necrotizing fasciitis were found . The incidence of CNF was 2.6% among the infections hospitalized on the OMS service . There were 7 male and 4 female patients . Eight patients were older than 60 years of age . Seven patients had immunocompromising conditions, including diabetes mellitus in 4, concurrent administration of steroid in 2, uremia in 1, and a thymus carcinoma in 1 . All patients showed parapharyngeal space involvement; four also showed retropharyngeal space involvement . Gas was found in the computed tomography scan in 6 patients, extending to cranial base in 3 of them . Anaerobes were isolated in 73% of the infections, whereas Streptococcus species were uniformly present . All patients received 1 or more debridements . Major complications occurred in 4 patients, including mediastinitis in 4, septic shock in 2, lung empyema in 1, pleural effusion in 2, and pericardial effusion in 1 . All major complications developed in the immunocompromised patients, leading to 2 deaths . CONCLUSION: The mortality rate in this study was 18% . Early surgical debridement, intensive medical care, and a multidisciplinary approach are advocated in the management of CNF. Eur J Clin Microbiol Infect Dis, 2000 Oct, 19(10), 755 - 8 Macrolide resistance phenotypes and genotypes in French clinical isolates of Streptococcus pneumoniae . Observatoire de Normandie du Pneumocoque; Angot P et al.; The aim of this study was to analyze the mechanisms of macrolide resistance in French clinical isolates of Streptococcus pneumoniae . A total of 838 strains of pneumococci were isolated in 1997 in Normandy, a region of western France, by 19 microbiology laboratories . Fifty-three percent had displayed diminished susceptibility to penicillin G and 50% were resistant to erythromycin . From this collection, 92 penicillin-intermediate or -resistant and 18 penicillin-susceptible strains resistant to erythromycin were studied . The presence of erm genes coding for ribosomal methylases and of mefE-like genes responsible for macrolide efflux was screened by a multiplex polymerase chain reaction and confirmed by DNA/DNA hybridization . Of the 110 strains studied, 108 were cross-resistant to erythromycin, spiramycin and clindamycin, including 105 strains containing ermB-related genes and three strains that contained a combination of ermB- and mefE-related genes . Two strains apparently susceptible to clindamycin but resistant to spiramycin also contained ermB-related genes . No strain was resistant to erythromycin alone or contained only a mef-like gene . Therefore, resistance to erythromycin is mostly related to ribosomal methylation in this region of France. Indian J Ophthalmol, 2000 Jun, 48(2), 123 - 8 Spectrum of aetiological agents of postoperative endophthalmitis and antibiotic susceptibility of bacterial isolates; Anand AR et al.; PURPOSE: To determine the spectrum of infectious agents of postoperative endophthalmitis, the relationship with the time of onset of symptoms after surgery and the antibiotic susceptibilities of the aerobic bacterial isolates . METHODS: A retrospective review of microbiological records from January 1995 to December 1998 yielded 173 isolates from intraocular specimen of 170 patients with culture-proven postoperative endophthalmitis . Antibiotic susceptibility of these isolates was determined for various ocular antibiotics using the Kirby-Bauer disk-diffusion test . Based on the time of onset of illness, clinical presentation was classified into acute, delayed and chronic . RESULTS: Among 170 cases, 71 (41.7%) were attributable to gram-negative, 64 (37.6%) to gram-positive bacteria, and 37 (21.8%) to fungi . Gram-negative bacteria included P . aeruginosa (29;17.1%), other Pseudomonas spp (15;8.8%), non-fermenters (18;10.6%) and others (10;5.8%) . Among these, 40 of 72 (55.5%) were sensitive to gentamicin, 47 of 72 (65.2%) to cefotaxime, 47 of 69 (68.1%) to amikacin, 52 of 71 (73.2%) to ciprofloxacin, and 25 of 40 (62.5%) to ceftazidime . The gram-positive bacteria included S . epidermidis (22;12.9%), S . aureus (13;7.6%), P . acnes (10;5.9%), Enterococcus spp (4;2.3%), Streptococcus spp (7;4.1%) and others (8;4.8%) . Among these, 41 of 53 (77.3%) were sensitive to gentamicin, 47 of 53 (88.6%) to cefotaxime, 46 of 52 (88.4%) to ciprofloxacin, 38 of 41 (92.6%) to cefazolin and 27 of 37 (72.9%) to ceftazidime . All gram-positive bacteria were sensitive to vancomycin . CONCLUSION: In this large series of postoperative endophthalmitis, gram-negative bacilli followed by fungi accounted for the largest number of cases . A high degree of resistance of gram-negative bacilli to gentamicin, cefotaxime, amikacin and ceftazidime was recorded. J Mol Evol, 2000 Dec, 51(6), 520 - 31 Structural evidence for the evolution of pyrogenic toxin superantigens; Mitchell DT et al.; Pathogenic bacteria have evolved a wide variety of toxins to invade and attack host organisms . In particular, strains of the bacteria Staphylococcus aureus and Streptococcus pyogenes produce a family of pyrogenic toxin superantigens (PTSAgs) that can cause illness, e.g., toxic shock syndrome, or synergize with a number of other immune system disorders . The PTSAgs are all similar in size and have a conserved two-domain tertiary fold despite minimal amino acid sequence identity . The tertiary structure of PTSAg domain 1 is similar to the immunoglobulin binding motif of streptococcal proteins G and L . PTSAg domain 2 resembles members of the oligosaccharide/oligonucleotide binding fold family that includes the B subunits of the AB(5) heat-labile enterotoxins, cholera toxin, pertussis toxin, and verotoxin . The strong structural homology between the pyrogenic toxins and other bacterial proteins suggests that the PTSAgs evolved through the recombination of two smaller beta-strand motifs. Vaccine, 2000 Nov 22, 19(7-8), 850 - 61 Preparation and preclinical evaluation of experimental group B streptococcus type III polysaccharide-cholera toxin B subunit conjugate vaccine for intranasal immunization; Shen X et al.; Streptococcus group B (GBS) is usually carried asymptomatically in the vaginal tract of women and can be transferred to the newborn during parturition . Serum antibodies to the capsular polysaccharide (CPS) can prevent invasive diseases, whereas immunity acting at the mucosal surface may be more important to inhibit the mucosal colonization of GBS and thus the risk of infection for the newborn . We prepared different GBS type III CPS-protein conjugate vaccines and evaluated their systemic and mucosal immunogenicity in mice . GBS type III CPS was conjugated to tetanus toxoid (TT) or recombinant cholera toxin B subunit (rCTB) either directly or to rCTB indirectly via TT . The conjugation was performed by different methods: (1) CPS was coupled to TT with 1-ethyl-3 (3-dimethylaminopropyl)-carbodiimide (EDAC), using adipic acid dihydrazide (ADH) as a spacer; (2) CPS was conjugated with rCTB using reductive amination; or, (3) N-succinimidyl 3-(2-pyridyldithio) propionate (SPDP) was used to bind rCTB to the TT of the CPS-TT conjugate . Mice were immunized with these conjugates or purified CPS by subcutaneous (s.c.) and intranasal (i . n.) routes . Antibodies to GBS III in serum, lungs and vagina were measured with ELISA . All of the CPS-protein conjugates were superior to unconjugated CPS in eliciting CPS-specific immune responses in serum and mucosal tissue extracts . The conjugates, when administrated s.c., induced only IgG responses in serum, lung and vagina, while i.n . vaccination also elicited IgA responses in the lungs and vagina . The CPS-TT conjugate administrated i.n . induced a strong serum IgG, but only a weak mucosal IgA response, while the CPS-rCTB conjugate elicited high IgG as well as IgA antibodies in the lungs after i.n . immunization . GBS III CPS-TT conjugated with rCTB produced a strong systemic and local anti-CPSIII response after i.n . administration . Co-administration of CT as adjuvant enhanced the anti-CPS systemic and mucosal immune responses further after i.n . administration with the CPS conjugates . These findings indicate that: (i) i.n . immunization with GBS CPS-protein conjugates was more effective than s.c immunization for stimulating serum as well as mucosal immune responses; (ii) rCTB as a carrier protein for GBS III CPS could markedly improve the mucosal immune response; and (iii) the experimental GBS type III CPS conjugates containing rCTB should be investigated as mucosal vaccine to prevent GBS infection in humans. Int J Pediatr Otorhinolaryngol, 2000 Dec 1, 56(2), 129 - 34 Prevention of acute mastoiditis: fact or fiction? Linder TE, Briner HR, Bischoff T. Acute mastoiditis is the most common complication of acute otitis media (AOM) . In recent years routine antibiotic treatment for acute middle ear infections was questioned and even abandoned in some countries . The goal of our study was to investigate the influence of antibiotic treatment on the occurrence and clinical outcome of acute mastoiditis and to analyze the bacteriological findings . A retrospective case record study of 48 patients with 50 episodes of acute mastoiditis hospitalized at our tertiary-care center between 1992 and 1999 was performed . Twenty-three patients (48%) received antibiotic treatment before admission whereas 25 (52%) did not . The group of patients without antibiotic pretreatment were younger (mean, 6 years) than patients with antibiotics (mean, 18 years) and their referral was delayed . The most common isolated single pathogen was Streptococcus pneumoniae . All pneumococci were sensitive to penicillin . Acute mastoiditis may be the first clinical sign of a middle ear infection, especially in very young children . Adequate antibiotic pretreatment cannot invariably prevent the development of acute mastoiditis even in the absence of penicillin resistant pathogens. Mol Microbiol, 2000 Nov, 38(4), 867 - 78 Cross-regulation of competence pheromone production and export in the early control of transformation in Streptococcus pneumoniae; Martin B et al.; Two operons, comAB and comCDE, play a key role in the co-ordination of spontaneous competence development in cultures of Streptococcus pneumoniae . ComAB is required for export of the comC-encoded competence-stimulating peptide (CSP) . Upon CSP binding, the histidine kinase ComD activates ComE, its cognate response regulator, required for autoinduction of comCDE and for induction of the late competence genes . To understand better the early control of competence development, mutants upregulating comCDE (ComCDEUP) were isolated using a comC-lacZ transcriptional fusion . Mutants were generated by polymerase chain reaction mutagenesis of the comCDE region and by in vitro transposon mutagenesis of the chromosome . Both types of ComCDEUP mutants exhibited similar phenotypes . They differed from wild type in displaying trypsin-resistant transformation, competence under acid growth conditions and expression of comCDE under microaerobiosis; increased production of CSP in the mutants could account for the various phenotypes . The ComCDEUP transposon mutations included four independent insertions in the ciaR gene, which encodes the response regulator of a two-component system previously found to affect competence, and two immediately upstream of the comAB operon . The latter two resulted in comAB overexpression, indicating that CSP export is rate limiting . Among comDE point mutations, a single amino acid change in ComD (T233I) conferred constitutive, CSP-independent competence and resulted in comAB overexpression, providing support for the hypothesis that ComE regulates comAB; a ComE mutant (R120S) exhibited altered kinetics of competence shut-off . Collectively, these data indicate that pheromone autoinduction, cross-regulation of the comAB and comCDE operons and, possibly, competence shut-off contribute to the early control of competence development in S . pneumoniae . They argue for a metabolic control of competence, mediated directly or indirectly by CiaR, and they suggest that both comAB and comCDE are potential targets for regulation. Clin Infect Dis, 2001 Jan, 32(1), 9 - 16 Epub 2000 Dec 08. Spinal epidural abscesses in children: a 15-year experience and review of the literature; Auletta JJ et al.; We reviewed medical records and laboratory and diagnostic evaluations for 8 pediatric patients with spinal epidural abscesses who were treated during the last 15 years at our institution . Staphylococcus aureus was isolated from 5 of 8 epidural abscesses, including 2 abscesses with methicillin-resistant S . aureus . Unusual isolates were group B Streptococcus in a patient with chronic vesicouretral reflux associated with the posterior urethral valves and Aspergillus flavus in a patient with acute myelogenous leukemia . An analysis incorporating our results and a review of the English-language literature about abscesses in children and adults revealed differences related to age . Abscesses in children were more posterior in epidural location, had greater spinal column extension, and were associated with more favorable clinical outcomes than were abscesses in adults . Magnetic resonance imaging is the diagnostic procedure of choice; however, radionuclide bone scans should be considered for associated distant osteomyelitis in children . Prompt diagnosis and combined medical and surgical treatment remain the cornerstones for the prevention of adverse outcomes. Org Lett, 2000 Dec 14, 2(25), 4013 - 5 Asymmetric synthesis of quaternary centers . Total synthesis of (-)-malyngolide; Trost BM et al.; {structure} The deracemization of 3-nonyl-3,4-epoxybut-1-ene with Pd(0) in the presence of chiral ligands using p-methoxybenzyl alcohol as a nucleophile proceeds regio- and enantioselectively to form the monoprotected vinylglycidol in 99% ee . This chiral building block was converted in seven steps to (-)-malyngolide, an antibiotic showing significant activity against Mycobacterium smegmatis and Streptococcus pyogenes . An interesting aspect involves controlling the diastereoselectivity of protonation of an enolate via a distal hydroxyl group. J Pediatr Health Care, 2000 Nov-Dec, 14(6), 264 - 9 Early-onset neonatal group B streptococcal infection: implications for practice; Parks DK et al.; Group B streptococcus (GBS) is the leading bacterial infection associated with morbidity and mortality of newborns in the United States . Most neonatal infections can be prevented through the use of intrapartum antimicrobial prophylaxis in women who are at increased risk for transmitting infection to their newborns . However, prevention strategies have not been implemented widely or consistently, and the incidence of neonatal GBS disease has not declined . An understanding of GBS epidemiology, clinical presentation, and prevention strategies enhances the PNP's decision-making skills in the nursery and strengthens the PNP's ability to evaluate and compare new approaches to GBS prevention. J Invertebr Pathol, 2000 Nov, 76(4), 233 - 41 Apolipophorin-III and the interactions of lipoteichoic acids with the immediate immune responses of Galleria mellonella; Halwani AE et al.; We investigated the effects of lipoteichoic acids, surface components of Gram-positive bacteria, on the hemocytes and phenoloxidase activity in last instar Galleria mellonella larvae, as well as the binding of apolipophorin-III, an insect lipid-binding protein, to lipoteichoic acids . Binding of apolipophorin-III to lipoteichoic acid was studied using an assay based on 1,9-dimethylmethylene blue . Apolipophorin-III bound the lipoteichoic acids from Bacillus subtilis, Enterococcus hirae, and Streptococcus pyogenes and to intact cells of E . hirae . E . hirae lipoteichoic acid promoted the binding of apolipophorin-III to the cells of this species . All lipoteichoic acids tested caused a dose- and time-dependent drop in the total counts of hemocytes and, depending on the species of lipoteichoic acid, partial or complete depletion of plasmatocytes . Granulocyte counts were not affected . Apolipophorin-III prevented partially the loss of plasmatocytes due to B . subtilis lipoteichoic acid . All three lipoteichoic acids studied activated phenoloxidase in vitro; injections of B . subtilis lipoteichoic acid into the larvae elevated the phenoloxidase activity, whereas injections of E . hirae or S . pyogenes lipoteichoic acid, or apolipophorin-III alone, suppressed it . Apolipophorin-III decreased the activation of phenoloxidase by B . subtilis lipoteichoic acid. J Infect Dis, 2001 Jan 15, 183(2), 253 - 260 Epub 2000 Dec 08. Serum samples from infants vaccinated with a pneumococcal conjugate vaccine, PncT, protect mice against invasive infection caused by Streptococcus pneumoniae serotypes 6A and 6B; Saeland E et al.; Streptococcus pneumoniae serogroup 6 is an important cause of respiratory tract disease worldwide . Vaccination with 6B polysaccharide induces antibody response to the cross-reacting serotype 6A, but the protective capacity of 6A antibodies induced in infants remains unknown . In this study, passive immunization with serum samples obtained from infants vaccinated with an octavalent polysaccharide protein conjugate vaccine, PncT, protected mice against bacteremia and/or lung infection caused by intranasal challenge with serotypes 6B and 6A . Protective infant serum samples had significantly higher serotype-specific IgG levels and opsonic activity than did nonprotective serum samples . The protective level to either serotype was approximately 1 microg of specific IgG antibodies injected per mouse (corresponding to approximately 0.3 microg/mL) . The protection was strongly related to opsonophagocytic antibody levels measured in vitro . These results demonstrate that PncT induces antibodies in infants that protect mice against invasive disease caused by the homologous serotype and by the cross-reacting serotype 6A. Enferm Infecc Microbiol Clin, 2000 Aug-Sep, 18(7), 314 - 8 {Resistance to penicillin and other antimicrobials in 301 clinical isolates of Streptococcus pneumoniae}; Navarro C et al.; BACKGROUND: The aim of this study was to assess the susceptibility to penicillin of Streptococcus pneumoniae clinical strains and to analyze the association between penicillin resistance and cefotaxime and cefixime activity in S . pneumoniae isolates with decreased sensitivity to penicillin . METHODS: 301 S . pneumoniae clinical strains were isolated from patients during 1995-1996 . Susceptibility to penicillin, cefotaxime, cefepime, erythromycin, chloramphenicol, tetracycline, cotrimoxazole and ciprofloxacin were studied . RESULTS: 38.2% isolates were penicillin-susceptible and 61.8% were penicillin-resistant; 20.6% showed high-level resistance . Resistance rates to erythromycin, chloramphenicol, tetracycline, cotrimoxazole and ciprofloxacin were, respectively, 30.9, 30.2, 40.9, 66.4, and 13.3% overall, and 54.8, 54.8, 61.3, and 93.5% in the 62 strains with high-level resistance to penicillin . Strains resistant to cefotaxime and cefepime were 13.9 and 14.9%, respectively . MIC50 and MIC90 for cefotaxime and cefepime in penicillin-resistant strains were 0.5 and 1 mg/ml . CONCLUSIONS: A high proportion of S . pneumoniae isolates showed resistance to penicillin, in agreement with other Spanish reports . Moreover, resistance to penicillin was significantly associated (p < 0.001) with resistance to erythromycin, chloramphenicol, tetracycline and cotrimoxazole, but not with ciprofloxacin . MIC50 and MIC90 for cefotaxime and cefepime were similar, and lower than those for penicillin in penicillin-resistant pneumococci strains. Rozhl Chir, 2000 Sep, 79(9), 414 - 7 {Streptococcus pneumoniae--an infectious agent in coxitis}; Pospisil M et al.; Based on their own observation the authors describe pneumococcal coxitis in a young man . With regard to the atypical clinical picture of the disease the authors draw attention to the necessity to consider in the differential diagnosis of pain in the inguinal and coxal area also infectious arthritis . This concerns in the first place physicians in the first line of contact. Diagn Microbiol Infect Dis, 2000 Nov, 38(3), 177 - 9 In vitro activity of GAR-936 against vancomycin-resistant enterococci, methicillin-resistant Staphylococcus aureus and penicillin-resistant Streptococcus pneumoniae; Patel R et al.; We report the activity of the new glycylcycline antimicrobial agent GAR-936 against 37 clinical isolates of vancomycin-resistant enterococci (including organisms carrying the vanA, vanB, vanC-1, and vanC-2/3 genes), 26 clinical isolates of methicillin-resistant S . aureus and 30 clinical isolates of high-level penicillin-resistant S . pneumoniae . All isolates of vancomycin-resistant enterococci, methicillin-resistant S . aureus, and penicillin-resistant S . pneumoniae were inhibited by < or = 1, < or = 2, or < or = 0.25 microg/ml of GAR-936, respectively . Time kill experiments using vancomycin-resistant enterococci did not demonstrate synergy or antagonism between 2 microg/ml of GAR-936 and 0.25 microg/ml of quinupristin/dalfopristin. Diagn Microbiol Infect Dis, 2000 Nov, 38(3), 171 - 2 Group A streptococcal appendicitis in a patient with AIDS; Tufariello JM et al.; A man with AIDS developed appendicitis and bacteremia caused by Group A streptococcus, neither of which is considered an opportunistic infection . Group A streptococcus is rarely implicated in appendicitis in children and has not previously been reported in an adult . Immunodeficiency might have predisposed the patient to this unusual infection. Diagn Microbiol Infect Dis, 2000 Nov, 38(3), 151 - 7 The use of Monte Carlo simulation to examine pharmacodynamic variance of drugs: fluoroquinolone pharmacodynamics against Streptococcus pneumoniae; Ambrose PG et al.; BACKGROUND: For fluoroquinolones, AUC:MIC ratios correlate with maximal bacterial eradication in in vitro models of infection and favorable cure rates in humans with respiratory tract infection . Inter-subject pharmacokinetic and MIC variability may impact the probability of attaining optimal AUC:MIC ratios and hence favorable clinical outcome . METHODS: Monte Carlo simulation was utilized to estimate the probability of attaining AUC:MIC ratios of 30, 40, 50, 60, 70, 80, 90, 100, 110 and 120 using AUC values from patients treated with either gatifloxacin or levofloxacin and microbiologic activity against S . pneumoniae observed in 1997 SENTRY Antimicrobial Surveillance Program . RESULTS: The probability curves for 5000 patient simulations were plotted . The median AUC:MIC ratios were 120 for gatifloxacin and 50.5 for levofloxacin . The probability of attaining AUC:MIC ratios of 30, 50, 70 and 100 for gatifloxacin were 94%, 86%, 78% and 62%, and for levofloxacin were 80%, 51%, 31% and 17%, respectively . CONCLUSION: Gatifloxacin has a higher probability of achieving target AUC:MIC ratios than levofloxacin . Monte Carlo simulation, using patient-based AUC and MIC distributions, may have implications for selection of optimal antibiotics for the empiric treatment of infections . Moreover, Monte Carlo simulation may have utility in the determination of MIC breakpoints. Neurosci Lett, 2000 Dec 22, 296(2-3), 137 - 40 Spatial memory and learning deficits after experimental pneumococcal meningitis in mice; Wellmer A et al.; Survivors of bacterial meningitis frequently suffer from long-term sequelae, particularly from learning and memory deficits . For this reason, spatial memory and learning was studied in a mouse model of ceftriaxone-treated Streptococcus pneumoniae meningitis . Persistent deficits of spatial learning despite normal motor function were observed in mice infected with 10(4) colony-forming units (CFU) in 25 microl of saline into the right forebrain in comparison to mice treated with an equal amount of saline . Survivors of meningitis performed significantly worse in memorizing a hidden platform in a Morris water maze . After 2 weeks, the difference between post-meningitis and control mice diminished . Yet, when the platform was moved after 180 days, learning of the new location was still strongly impaired in mice surviving meningitis. Int Microbiol, 1999 Sep, 2(3), 169 - 76 Functional organization of the gene cluster involved in the synthesis of the pneumococcal capsule; Garcia E et al.; Streptococcus pneumoniae is a major human pathogen and its capsular polysaccharide has been shown to be the main virulence factor . The molecular organization of the genes governing the formation of this capsule was not studied until the 1990s . The capsular clusters (cap) of eight of the 90 known pneumococcal types have now been studied . The cap operon, located between the dexB and aliA genes, is arranged as a central region comprising the genes coding for the specific-type polysaccharide, flanked by open reading frames that are mostly common to all of the serotypes . The biochemical functions of 24 genes required for capsular polysaccharide biosynthesis have been elucidated but the precise role of the flanking regions in capsular formation is unknown . The natural genetic transformation characteristic of pneumococci, the arrangement of the cap locus and the abundance of transposable elements at this locus favor the genetic variability of the capsule in this microorganism . These well-documented observations together with the finding that some genes located outside the cap cluster may also participate in capsule formation increase the complexity of pneumococcal infection control. Int Microbiol, 1999 Mar, 2(1), 23 - 8 Construction of a new Streptococcus pneumoniae-Escherichia coli shuttle vector based on the replicon of an indigenous pneumococcal cryptic plasmid; Munoz R et al.; The nucleotide sequence of a cryptic plasmid (pRMG1) isolated from a type 1 Streptococcus pneumoniae has been determined and two recombinant plasmids, pRMGE1 and pRMGE2, bearing the pRMG1 replicon have been constructed . pRMGE2 is a shuttle vector for Escherichia coli and S . pneumoniae . The important characteristics of this cloning vector are: a size of 5.5 kb including a 1.4 kb fragment of pRMG1 (containing a double-stranded replication origin and an open reading frame encoding a putative replication initiation protein), a multicloning site, two antibiotic resistance markers for selection of plasmid containing cells, and blue-white colony screening in E . coli for identification of insert-containing plasmids. Syst Appl Microbiol, 2000 Oct, 23(3), 330 - 2 Identification of methionine-processed HPr in the equine pathogen Streptococcus equi; Sutcliffe IC et al.; Using preparative electrophoresis, a low molecular weight protein has been partially purified from a cell extract of the equine pathogen Streptococcus equi susp . equi . N-terminal sequence analysis and Western blotting revealed the protein to be HPr, a central component of the phosphoenolpyruvate:sugar phosphotransferase system (PTS) . Interestingly, the only form of the HPr protein detected in S . equi was one with the amino-terminal methionine removed, a modification that has previously been associated with surface localization of streptococcal HPr proteins. Syst Appl Microbiol, 2000 Oct, 23(3), 325 - 9 Characterization of acid phosphatase activities in the equine pathogen Streptococcus equi; Hamilton A et al.; Acid phosphatases hydrolyse phosphomonoesters at acidic pH in a variety of physiological contexts . The recently defined class C family of acid phosphatases includes the 32 kDa LppC lipoprotein of Streptococcus equisimilis . To define further the distribution of acid phosphatases in the genus Streptococcus we have examined the equine pathogens Streptococcus equi subsp . equi and Streptococcus equi subsp . zooepidemicus . Whole cell assays indicated that these organisms possess two acid phosphatases with activity optima at pH 5.0 and pH 6.0-6.5 and that only the former of these was, like LppC, resistant to EDTA . Western blotting with a polyclonal anti-LppC antiserum revealed the presence of a cross-reactive 32 kDa protein in both organisms . The cross-reactive protein in S . equi was shown to be a surface accessible lipoprotein as its processing was inhibited by the antibiotic globomycin and it was released from whole cells by treatment with trypsin . The presence of DNA sequences homologous to the S . equisimilis lppC gene were confirmed by PCR . These data strongly suggest that Streptococcus equi subsp . equi and Streptococcus equi subsp . zooepidemicus produce a lipoprotein acid phosphatase homologous to LppC of S . equisimilis. Biochemistry, 2000 Dec 12, 39(49), 14993 - 5001 The structure of UDP-N-acetylglucosamine 2-epimerase reveals homology to phosphoglycosyl transferases; Campbell RE et al.; Bacterial UDP-N-acetylglucosamine 2-epimerase catalyzes the reversible epimerization at C-2 of UDP-N-acetylglucosamine (UDP-GlcNAc) and thereby provides bacteria with UDP-N-acetylmannosamine (UDP-ManNAc), the activated donor of ManNAc residues . ManNAc is critical for several processes in bacteria, including formation of the antiphagocytic capsular polysaccharide of pathogens such as Streptococcus pneumoniae types 19F and 19A . We have determined the X-ray structure (2.5 A) of UDP-GlcNAc 2-epimerase with bound UDP and identified a previously unsuspected structural homology with the enzymes glycogen phosphorylase and T4 phage beta-glucosyltransferase . The relationship to these phosphoglycosyl transferases is very intriguing in terms of possible similarities in the catalytic mechanisms . Specifically, this observation is consistent with the proposal that the UDP-GlcNAc 2-epimerase-catalyzed elimination and re-addition of UDP to the glycal intermediate may proceed through a transition state with significant oxocarbenium ion-like character . The homodimeric epimerase is composed of two similar alpha/beta/alpha sandwich domains with the active site located in the deep cleft at the domain interface . Comparison of the multiple copies in the asymmetric unit has revealed that the epimerase can undergo a 10 degrees interdomain rotation that is implicated in the regulatory mechanism . A structure-based sequence alignment has identified several basic residues in the active site that may be involved in the proton transfer at C-2 or stabilization of the proposed oxocarbenium ion-like transition state . This insight into the structure of the bacterial epimerase is applicable to the homologous N-terminal domain of the bifunctional mammalian UDP-GlcNAc "hydrolyzing" 2-epimerase/ManNAc kinase that catalyzes the rate-determining step in the sialic acid biosynthetic pathway. Eur J Biochem, 2000 Dec, 267(24), 7147 - 57 Structures of two cell wall-associated polysaccharides of a Streptococcus mitis biovar 1 strain . A unique teichoic acid-like polysaccharide and the group O antigen which is a C-polysaccharide in common with pneumococci; Bergstrom N et al.; The cell wall of Streptococcus mitis biovar 1 strain SK137 contains the C-polysaccharide known as the common antigen of a closely related species Streptococcus pneumoniae, and a teichoic acid-like polysaccharide with a unique structure . The two polysaccharides are different entities and could be partially separated by gel chromatography . The structures of the two polysaccharides were determined by chemical methods and by NMR spectroscopy . The teichoic acid-like polymer has a heptasaccharide phosphate repeating unit with the following structure: The structure neither contains ribitol nor glycerol phosphate as classical teichoic acids do, thus we have used the expression teichoic acid-like for this polysaccharide . The following structure of the C-polysaccharide repeating unit was established: where AAT is 2-acetamido-4-amino-2,4, 6-trideoxy-D-galactose . It has a carbohydrate backbone identical to that of one of the two structures of C-polysaccharide previously identified in S . pneumoniae . C-polysaccharide of S . mitis is characterized by the presence, in each repeating unit, of two residues of phosphocholine and both galactosamine residues in the N-acetylated form . Immunochemical analysis showed that C-polysaccharide constitutes the Lancefield group O antigen . Studies using mAbs directed against the backbone and against the phosphocholine moiety of the C-polysaccharide revealed several different patterns of these epitopes among 95 S . mitis and Streptococcus oralis strains tested and the exclusive presence of the group O antigen in the majority of S . mitis biovar 1 strains. Vet Rec, 2000 Nov 11, 147(20), 563 - 7 Investigations towards an efficacious and safe strangles vaccine: submucosal vaccination with a live attenuated Streptococcus equi; Jacobs AA et al.; As part of a search for a safe and efficacious strangles vaccine, several different vaccines and different vaccination routes were tested in foals . The degree of protection was evaluated after an intranasal challenge with virulent Streptococcus equi by clinical, postmortem and bacteriological examinations . Inactivated vaccines containing either native purified M-protein (500 microg per dose) or whole S equi cells (10(10) cells per dose) administered at least twice intramuscularly at intervals of four weeks, did not protect against challenge . Different live attenuated S equi mutants administered at least twice at intervals of four weeks by the intranasal route were either safe but not protective or caused strangles . In contrast, a live attenuated deletion mutant administered intramuscularly, induced complete protection but also induced unacceptable local reactions at the site of vaccination . Submucosal vaccination in the inner side of the upper lip with the live attenuated mutant at > or =10(8) colony-forming units per dose, appeared to be safe and efficacious in foals as young as four months of age . The submucosal vaccinations caused small transient swellings that resolved completely within two weeks, and postmortem no vaccine remnants or other abnormalities were found at the site of vaccination. Handchir Mikrochir Plast Chir, 2000 Sep, 32(5), 343 - 6 {Chronic paronychia and synovialitis of extensor tendons due to Mycobacterium marinum . Is diagnosis or treatment the problem?}; Witthaut J et al.; Most infections of the upper extremity are caused by staphylococcus or streptococcus and respond well to beta-lactam antibiotics . Hand surgeons should be aware of the possible diagnosis of Mycobacterium marinum infection: 90% of the lesions are found in the upper extremity . We present a case of a chronic, cutaneous lesion of the right middle finger with synovialitis of the extensor tendons observed in a 35-year-old woman . Routine cultures from tissue of the infected finger led to the diagnosis of paronychia due to staphylococcus aureus . Despite surgical and antibacterial treatment, the lesion persisted and the patient developed multiple raised, non-tender satellite lesions to the right hand and elbow . Based on the clinical aspect and a detailed history (she kept fish and had suffered a chicken bone stab to her middle finger 12 weeks earlier), we suspected a Mycobacterium marinum infection . Tissue was obtained mainly by synovialectomy . Culture of the biopsy tissue for Mycobacterium marinum confirmed the diagnosis . The patient responded to a triple therapy (rifabutin, ethambutol and clarithromycin) and had an uncomplicated recovery . The importance of a high index of suspicion, adequate examination and a complete patient's history for a correct diagnosis is stressed . Culture for Mycobacterium marinum is not routinely performed and ought to be initiated once an infection is suspected . We also discuss the best timing for the onset of medical treatment. J Neurol Sci, 2000 Dec 15, 182(1), 36 - 44 Adult bacterial meningitis in Southern Taiwan: epidemiologic trend and prognostic factors; Lu CH et al.; In two investigative phases over a 13.5-year study period (January 1986-June 1999), 202 adult patients with culture-proven bacterial meningitis were enrolled in this study . In order to determine the epidemiologic trend, prognostic factors and therapeutic results for this disease . Klebsiella pneumoniae (K . pneumoniae), Pseudomonas aeruginosa, and Streptococcus pneumoniae were the three most commonly revealed pathogens, accounting for about 48% of the episodes . Although there was a change in relative frequency for the pathogens, K . pneumoniae remained the most prevalent during the two periods studied (January 1986-December 1992 and January 1993-June 1999) . Multiantibiotic resistant strains have been in evidence since their appearance in 1994, with most of our patients acquiring their infection nosocomially . The overall mortality rates during the two periods were 40% and 34%, respectively . In stepwise logistic regression analysis, only initial conscious level, appropriate antibiotic therapy and septic shock were independently associated with mortality, after adjustment for other potentially confounding factors . Initial empirical antibiotics with both third-generation cephalosporin and penicillin G, should be considered for the majority of meningitis cases resulting from infection with Gram-negative bacilli and streptococcal species . Besides the evolution of newer pathogens, there has been increasing incidence for nosocomially acquired bacterial meningitis for patients postneurosurgery, with the emergence of resistant strains presenting a therapeutic challenge in recent years . Vancomycin and imipenem/cilastatin should be considered as the initial empirical antibiotics of choice for the treatment of this special group of patients. J Antimicrob Chemother, 2000 Dec, 46(6), 973 - 80 Antagonism between penicillin and erythromycin against Streptococcus pneumoniae in vitro and in vivo; Johansen HK et al.; The combination of beta-lactam antibiotics and macrolides is often recommended for the initial empirical treatment of acute pneumonia in order to obtain activity against the most important pathogens . Theoretically, this combination may be inexpedient, as the bacteriostatic agent may antagonize the effect of the bactericidal agent . In this study, the possible interaction between penicillin and erythromycin was investigated in vitro and in vivo against four clinical isolates of Streptococcus pneumoniae with MICs of penicillin ranging from 0.016 to 0.5 mg/L and of erythromycin from 0 . 25 to >128 mg/L . In vitro time-kill curves were generated with clinically relevant concentrations of penicillin (10 mg/L) and erythromycin (1 mg/L), either individually or in combination . Antagonism between penicillin and erythromycin was observed for the four isolates . In vivo interaction was investigated in the mouse peritonitis model . After intraperitoneal inoculation, penicillin and erythromycin were given either individually or in combination . For two of the four isolates, mortality was significantly higher in the groups treated with the combination of penicillin and erythromycin than in the groups treated with penicillin alone {32/36 (86%) vs . 3/12 (25%), P<0.05; and 24/36 (67%) vs . 3/12 (25%), P<0.05, respectively} . Using the mouse peritonitis model, in vivo time-kill curves showed that there was antagonism between erythromycin and penicillin for the examined isolate . The antagonism demonstrated in vitro and in vivo between penicillin and erythromycin suggests that ss-lactam antibiotics and macrolides should not be administered together unless pneumococcal infection is ruled out. J Antimicrob Chemother, 2000 Dec, 46(6), 959 - 64 Streptococcus pyogenes resistance to erythromycin in relation to macrolide consumption in Spain (1986-1997); Granizo JJ et al.; The relationship between Streptococcus pyogenes resistance to erythromycin and macrolide consumption in Spain was studied . Erythromycin resistance was highly correlated with the consumption of total macrolides (r = 0.88, P<0.01) . When macrolides were grouped into posological subgroups according to their pharmacokinetic and pharmacodynamic properties and analysed separately, erythromycin resistance appeared to be related mainly to those macrolides taken twice daily (bd) (r = 0.86, P<0.01) and those taken once daily (od) (r = 0.87, P<0.01), but not to those taken four (qds) or three times a day (tds) (r = -0.04, P: = 0.90) . A progressive increase in the erythromycin resistance curve was seen after the consecutive introduction of both bd and od macrolides, which contributed to the increase in the total macrolide consumption, replacing tds macrolide prescription . Although this ecological analysis cannot establish an unequivocal causal relationship between antibiotic consumption and S . pyogenes resistance, the data are consistent with the hypothesis that widespread use of macrolides, mainly of bd and od macrolides, resulted in an increased prevalence of S . pyogenes resistant to erythromycin in Spain. J Antimicrob Chemother, 2000 Dec, 46(6), 909 - 15 In vitro development of resistance to ceftriaxone, cefprozil and azithromycin in Streptococcus pneumoniae; Nagai K et al.; Approval of ceftriaxone for the treatment of otitis media has led to fear of selection of resistant mutants owing to widespread use . To test this, we examined the ability of sequential subcultures in sub-MICs of ceftriaxone, cefprozil and azithromycin to select resistant mutants in 12 pneumococci . Daily subculturing was performed 50 times or until mutants with raised ceftriaxone, cefprozil or azithromycin MICs were selected . Of eight ceftriaxone-susceptible parents, ceftriaxone did not select for any resistant mutants, while cefprozil selected for four mutants (MICs 2-4 mg/L after 21-50 subcultures) . Among four ceftriaxone-resistant parents, subculturing in ceftriaxone selected for one stable mutant with raised ceftriaxone MIC (>16 mg/L after 21 subcultures) and subculturing in cefprozil selected for one mutant with raised cefprozil MIC (64 mg/L after 44 subcultures) . Mutations were observed in pbp2x and pbp1a . Among six azithromycin-susceptible parents, subculturing in azithromycin selected for five resistant mutants (MIC 0.5-32 mg/L after 10-42 passages) and among six azithromycin-resistant strains, subculturing selected for mutants with raised azithromycin MICs in all six strains (MIC 16-32 mg/L after 4-18 passages) . All azithromycin-resistant mutants derived from azithromycinsusceptible parents had mutations in domain V of 23S rRNA while all azithromycin-resistant parents and derived mutants had mefE . Single-step mutation rates among the 12 strains at the MIC ranged from 1.5 x 10(-6) to <6.2 x 10(-10) for ceftriaxone, >1.3 x 10(-5) to 8.9 x 10(-8) for cefprozil and >1.1 x 10(-6) to 6.7 x 10(-10) for azithromycin . Multi-step and single-step testing showed that ceftriaxone selected for resistant mutants less often than cefprozil and azithromycin. J Antimicrob Chemother, 2000 Dec, 46(6), 905 - 8 In vitro activity of ketolides telithromycin and HMR 3004 against italian isolates of Streptococcus pyogenes and Streptococcus pneumoniae with different erythromycin susceptibility; Giovanetti E et al.; Two ketolides, telithromycin and HMR 3004, were evaluated for their in vitro activity against erythromycin-susceptible and -resistant strains of Streptococcus pyogenes and Streptococcus pneumoniae . On the basis of their resistance to macrolide, lincosamide and streptogramin (MLS) antibiotics, erythromycin-resistant test strains were assigned to the constitutive resistance (cMLS) phenotype, the inducible resistance (iMLS) phenotype or the M phenotype . iMLS S . pyogenes strains were further subdivided into the three recently described subtypes iMLS-A, -B and -C . Telithromycin and HMR 3004 were uniformly and highly active against pneumococci (regardless of their susceptibility or resistance to erythromycin and/or penicillin), erythromycin-susceptible S . pyogenes and erythromycin-resistant S . pyogenes strains of the M phenotype (in which resistance is mediated by an efflux system) or iMLS-B or -C phenotype (in which resistance is mediated by a methylase encoded by the ermTR gene) . Both ketolides were less active against erythromycin-resistant S . pyogenes strains with the cMLS phenotype or the iMLS-A subtype (where resistance is mediated by a methylase encoded by the ermAM gene), these strains ranging in phenotype from the upper limits of susceptibility to low-level resistant. J Clin Microbiol, 2000 Dec, 38(12), 4548 - 53 Genetic relatedne