In vitro selection and characterization of ceftobiprole-resistant methicillin-resistant Staphylococcus aureus

被引:70
作者
Baneriee, Ritu [1 ]
Gretes, Michael [2 ,3 ]
Basuino, Li [1 ]
Strynadka, Natalie [2 ,3 ]
Charnbers, Henry F. [4 ]
机构
[1] Univ Calif San Francisco, Dept Pediat, Div Infect Dis, San Francisco, CA 94143 USA
[2] Univ British Columbia, Dept Biochem & Mol Biol, Vancouver, BC V5Z 1M9, Canada
[3] Univ British Columbia, Ctr Blood Res, Vancouver, BC V5Z 1M9, Canada
[4] Univ Calif San Francisco, San Francisco Gen Hosp, Dept Med, Div Infect Dis, San Francisco, CA USA
关键词
D O I
10.1128/AAC.01403-07
中图分类号
Q93 [微生物学];
学科分类号
071005 ; 100705 ;
摘要
Methicillin-resistant Staphylococcus aureus (MRSA) is resistant to beta-lactam antibiotics because it expresses penicillin-binding protein 2a (PBP2a), a low-affinity penicillin-binding protein. An investigational broad-spectrum cephalosporin, ceftobiprole (BPR), binds PBP2a with high affinity and is active against MRSA. We hypothesized that BPR resistance could be mediated by mutations in mecA, the gene encoding PBP2a. We selected BPR-resistant mutants by passage in high-volume broth cultures containing subinhibitory concentrations of BPR. We used strain COLnex (which lacks chromosomal mecA) transformed with pAW8 (a plasmid vector only), pYK20 (a plasmid carrying wild-type mecA), or pYK21 (a plasmid carrying a mutant mecA gene corresponding to five PBP2a mutations). All strains became resistant to BPR by day 9 of passaging, but MICs continued to increase until day 21. MICs increased 256-fold (from 1 to 256 mu g/ml) for pAW8, 32-fold (from 4 to 128 mu g/ml) for pYK20, and 8-fold (from 16 to 128 mu g/ml) for pYK21. Strains carrying wild-type or mutant mecA developed six (pYK20 transformants) or four (pYK21 transformants) new mutations in mecA. The transformation of COLnex with a mecA mutant plasmid conferred BPR resistance, and the loss of mecA converted resistant strains into susceptible ones. Modeling studies predicted that several of the mecA mutations altered BPR binding; other mutations may have mediated resistance by influencing interactions with other proteins. Multiple mecA mutations were associated with BPR resistance in MRSA. BPR resistance also developed in the strain lacking mecA, suggesting a role for chromosomal genes.
引用
收藏
页码:2089 / 2096
页数:8
相关论文
共 29 条
  • [1] MRSA - the tip of the iceberg
    Appelbaum, PC
    [J]. CLINICAL MICROBIOLOGY AND INFECTION, 2006, 12 : 3 - 10
  • [2] Antistaphylococcal activity of ceftobiprole, a new broad-spectrum cephalosporin
    Bogdanovich, T
    Ednie, LM
    Shapiro, S
    Appelbaum, PC
    [J]. ANTIMICROBIAL AGENTS AND CHEMOTHERAPY, 2005, 49 (10) : 4210 - 4219
  • [3] Skin and bones: the bacterial cytoskeleton, cell wall, and cell morphogenesis
    Cabeen, Matthew T.
    Jacobs-Wagner, Christine
    [J]. JOURNAL OF CELL BIOLOGY, 2007, 179 (03) : 381 - 387
  • [4] A 2ND GENERATION FORCE-FIELD FOR THE SIMULATION OF PROTEINS, NUCLEIC-ACIDS, AND ORGANIC-MOLECULES
    CORNELL, WD
    CIEPLAK, P
    BAYLY, CI
    GOULD, IR
    MERZ, KM
    FERGUSON, DM
    SPELLMEYER, DC
    FOX, T
    CALDWELL, JW
    KOLLMAN, PA
    [J]. JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1995, 117 (19) : 5179 - 5197
  • [5] Binding of ceftobiprole and comparators to the penicillin-binding proteins of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus pneumoniae
    Davies, Todd A.
    Page, Malcolm G. P.
    Shang, Wenchi
    Andrew, Ted
    Kania, Malgosia
    Bush, Karen
    [J]. ANTIMICROBIAL AGENTS AND CHEMOTHERAPY, 2007, 51 (07) : 2621 - 2624
  • [6] DeLano W.L, 2002, The Pymol Molecular Graphics System Version 1.0
  • [7] REASSESSMENT OF THE NUMBER OF AUXILIARY GENES ESSENTIAL FOR EXPRESSION OF HIGH-LEVEL METHICILLIN RESISTANCE IN STAPHYLOCOCCUS-AUREUS
    DELENCASTRE, H
    TOMASZ, A
    [J]. ANTIMICROBIAL AGENTS AND CHEMOTHERAPY, 1994, 38 (11) : 2590 - 2598
  • [8] SWISS-MODEL and the Swiss-PdbViewer: An environment for comparative protein modeling
    Guex, N
    Peitsch, MC
    [J]. ELECTROPHORESIS, 1997, 18 (15) : 2714 - 2723
  • [9] HELLER S, 2004, CLIN MICROBIOL INFEC, V10, P163
  • [10] Effect of disruption of Staphylococcus aureus PBP4 gene on resistance to β-lactam antibiotics
    Katayama, Y
    Zhang, HZ
    Chambers, HF
    [J]. MICROBIAL DRUG RESISTANCE, 2003, 9 (04) : 329 - 336