암피실린/설박탐에 내성을 갖는 대장균과 포도상구균에 대한 베타-락타메이즈 억제제 CH2150과 설박탐의 항균효과 비교

Comparative Activities of CH2150 and Sulbactam as beta-Lactamase Inhibitors Against Escherichia coli and Staphylococcus Aureus Resistant to Ampicillin/Sulbactam

To overcome the problems of the resistance to clavulanic acid, many researchers are developing novel inhibitors that are not sensitive to new mutant beta-lactamases. In order to evaluate newly synthesized compound CH2150 (Sodium (3S.5R)-6(Z)-[1-{1-(2-{2-benzoxazoly}thioethyl)-l.2,3-txiazol-4-yl}methylene] penicillanate-1,1-dioxide) as a beta-lactamase inhibitor, we examined inhibitory activity of CH2150 against beta-lactamases of clinical isolates resistant to ampicillin/sulbactam(12 strains of Escherichia coli and 13 strains of Staphylococcus aureus), and compared with that of sulbactam. Nitrocefin was used as substrate for beta-lactamases, and the increase of absorbance was measured spectrophotometerically at 482 nm. beta-Lactarnase inhibition of CH2150 against beta-lactamases was 73 ~ 96% in E. coli and 76 ~ 79% in S. aureus. Comparatively, that of sulbactam was 96 ~ 100% and 96 ~ 100%, respectively. The inhibitory activity of CH2150 was slightly lower than that of sulbactam. The MIC values of ampicillin combined with CH2150 (2:1) for the clinical isolates were 4~512mcg/ml for E. coli and 1.0 ~ 64mcg/ml for S. aureus, whereas 0.5~16 mcg/ml for E. coli and 0.25~8mcg/ml for S. aureus when combined with sulbactam (2:1).