Alterations in MurM, a cell wall muropeptide branching enzyme, increase high-level penicillin and cephalosporin resistance in Streptococcus pneumoniae.
نویسندگان
چکیده
We report that alteration in MurM, an enzyme involved in the biosynthesis of branched-stem cell wall muropeptides, is required for maximal expression of penicillin and cefotaxime resistance in the pneumococcus. Hungarian isolate 3191 (penicillin MIC, 16 microg/ml; cefotaxime MIC, 4 microg/ml) was a source of donor DNA in transformation experiments. Penicillin-binding protein DNA was insufficient to transform recipient strain R6 to full resistance. Further transformation with altered murM DNA was required for full expression of donor penicillin and cefotaxime resistance.
منابع مشابه
New Aspects of the Interplay between Penicillin Binding Proteins, murM, and the Two-Component System CiaRH of Penicillin-Resistant Streptococcus pneumoniae Serotype 19A Isolates from Hungary
The Streptococcus pneumoniae clone Hungary19A-6 expresses unusually high levels of β-lactam resistance, which is in part due to mutations in the MurM gene, encoding a transferase involved in the synthesis of branched peptidoglycan. Moreover, it contains the allele ciaH232, encoding the histidine kinase CiaH (M. Müller, P. Marx, R. Hakenbeck, and R. Brückner, Microbiology 157:3104-3112, 2011, ht...
متن کاملIdentical Penicillin-Binding Domains in Penicillin-Binding Proteins of Streptococcus pneumoniae Clinical Isolates with Different Levels of -Lactam Resistance
We have sequenced the penicillin-binding domains of the complete repertoire of penicillin-binding proteins and MurM from 22 clinical isolates of Streptococcus pneumoniae that span a wide range of -lactam resistance levels. Evidence of mosaicism was found in the genes encoding PBP 1a, PBP 2b, PBP 2x, MurM, and, possibly, PBP 2a. Five isolates were found to have identical PBP and MurM sequences, ...
متن کاملIdentical penicillin-binding domains in penicillin-binding proteins of Streptococcus pneumoniae clinical isolates with different levels of beta-lactam resistance.
We have sequenced the penicillin-binding domains of the complete repertoire of penicillin-binding proteins and MurM from 22 clinical isolates of Streptococcus pneumoniae that span a wide range of beta-lactam resistance levels. Evidence of mosaicism was found in the genes encoding PBP 1a, PBP 2b, PBP 2x, MurM, and, possibly, PBP 2a. Five isolates were found to have identical PBP and MurM sequenc...
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ورودعنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 45 8 شماره
صفحات -
تاریخ انتشار 2001