A spectrum of changes occurs in peptidoglycan composition of glycopeptide-intermediate clinical Staphylococcus aureus isolates

Citation
S. Boyle-vavra et al., A spectrum of changes occurs in peptidoglycan composition of glycopeptide-intermediate clinical Staphylococcus aureus isolates, ANTIM AG CH, 45(1), 2001, pp. 280-287
Citations number
22
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Microbiology
Journal title
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY
ISSN journal
0066-4804 → ACNP
Volume
45
Issue
1
Year of publication
2001
Pages
280 - 287
Database
ISI
SICI code
0066-4804(200101)45:1<280:ASOCOI>2.0.ZU;2-T
Abstract
The mechanism of glycopeptide resistance in Staphylococcus aureus is not kn own with certainty. Because the target of vancomycin is the D-Ala-D-Ala ter minus of the stem peptide of the peptidoglycan precursor, by subjecting mur opeptides to reversed-phase high-performance liquid chromatography,,ve inve stigated peptidoglycan obtained from glycopeptide-intermediate S. aureus (G ISA) isolates far changes in composition and evaluated whether any peptidog lycan structural change was a consistent feature of clinical GISA isolates. GISA isolates Mu50 and Mu3 from Japan had the large glutamate-containing m onomeric peak demonstrated previously, although strain H1, a vancomycin-sus ceptible MRSA isolate from Japan that was clonally related to Mu3 and Mu50, and a femC mutant that we studied, did also. For the U.S. GISA isolates, s train NJ had a large monomeric peak with a retention time identical to that described for the glutamate-containing monomer in strains H1, Mu3, and Mu5 0. However, a much smaller corresponding peak was seen in GISA MI, and this peak was absent from both GISA PC and a recent GISA isolate obtained from an adult patient in Illinois (strain IL). These data suggest that a uniform alteration in peptidoglycan composition cannot be discerned among the GISA isolates and indicate that a single genetic or biochemical change is unlik ely to account for the glycopeptide resistance phenotype in the clinical GI SA isolates observed to date. Furthermore, a large monomeric glutamate-cont aining peak is not sufficient to confer the resistance phenotype.