Comparative study of the activities of beta lactamase inhibitors by nuclear magnetic resonance spectrometry
O'hara, K.; Shiomi, Y.; Kono, M.
Japanese Journal of Antibiotics 36(10): 2763-2768
1983
ISSN/ISBN: 0368-2781 PMID: 6371290 Document Number: 200695
Nuclear magnetic resonance (NMR) spectrometry were applied for the measurement of inhibitory activity of some drugs towards beta-lactamase in living cells. From the integrated values of the signals based on 5-H and 6-H of beta-lactam ring or methyl proton of C-2 position of ABPC as substrate, the inhibition dose of 50% (ID50 value) to beta-lactamase activity under the condition containing 10 mg of ABPC was calculated. The ID50 values (mg) of clavulanic acid (CVA), N-formimidoylthienamycin (MK 0787) and dicloxacillin (MDIPC) known as beta-lactamase inhibitor were less than 0.0001, 0.4 and 0.6, respectively, when each inhibitor was preincubated for 10 minutes. The ID50 values of cefoxitin (CFX), cefmetazole (CMZ), latamoxef (LMOX) and cefotaxime (CTX) known as beta-lactamase resistant drugs were 1.4, 1.3, 0.4 and more than 20.0, respectively, under same condition. From these results, it was clearly shown that CVA is excellent inhibitor to the beta-lactamase of Richmond's class III in living cells. And the inhibitory effect of CFX, CMZ and LMOX was also clearly shown.