Interaction of beta-lactam antibiotics with the penicillin-binding proteins of penicillin-resistant Streptococcus pneumoniae.
The binding of five structurally diverse beta-lactam antibiotics to penicillin-binding proteins (PBPs) of two clinical isolates of Streptococcus pneumoniae resistant to penicillin G was compared with that of a susceptible strain. A common feature of the PBP patterns of the resistant strains was the absence of PBP 1a detected in the susceptible strain. For each beta-lactam antibiotic tested, there appeared to be significant decreases in the affinity for BPB 1b, 2a and 2b of the resistant strains. We attempted to evaluate a quantitative correlation between the antibacterial activity of the drugs for three strains and their affinity for the various PBPs. A close correlation was found between the minimum inhibitory concentrations and the affinity for PBP 2a, but not for any of the other PBPs.
Ikeda
F
F
Department of Chemotherapy, Fujisawa Pharmaceutical Co., Osaka, Japan.
Yokota
Y
Y
Ikemoto
A
A
Teratani
N
N
Shimomura
K
K
Kanno
H
H
D000900:Anti-Bacterial Agents / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism*; D004347:Drug Interactions; D006602:Hexosyltransferases; D006801:Humans; D008826:Microbial Sensitivity Tests; D002267:Muramoylpentapeptide Carboxypeptidase / Q000378:metabolism*; D010403:Penicillin Resistance; D046915:Penicillin-Binding Proteins; D010458:Peptidyl Transferases; D011485:Protein Binding; D013296:Streptococcus pneumoniae / Q000187:drug effects / Q000378:metabolism*; D047090:beta-Lactams
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002352:Carrier Proteins; D046915:Penicillin-Binding Proteins; D047090:beta-Lactams; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D002267:Muramoylpentapeptide Carboxypeptidase