The detection of class A serine-carbapenemases among species of Enterobacteriaceae remains a challenging issue. Methods of identification for routine use in clinical microbiology laboratories have not been standardized to date. We developed a novel screening methodology suitable for countries with high basal levels of carbapenem resistance due to non-carbapenemase-mediated mechanisms and standa...

The mononuclear zinc thiolate complexes [(Tp(PhMe))Zn(S-R)], where Tp(PhMe) is hydrotris((3-methyl-5-phenyl)pyrazolyl)borate and (S-R) is benzyl thiolate, 4-nitrophenylthiolate, 4-trifluoromethylphenylthiolate, 4-chlorophenylthiolate, phenylthiolate, 2-methylphenylthiolate, 4-methylphenylthiolate, 4-methoxyphenylthiolate, or 4-hydroxyphenylthiolate, were synthesized. Representative members of t...

A clinical isolate of Serratia marcescens (FHSM4055) was highly resistant to carbapenem (MIC of imipenem, 100 mg/L) and was atypical in that it was negative in the aesculin-hydrolysis test. This parent strain was compared with the revertants S1 and S5, which had lost resistance to imipenem alone and to imipenem and piperacillin respectively. The MICs of imipenem for the revertants were 16- to 3...

d- and l-captopril are competitive inhibitors of metallo-beta-lactamases. For the enzymes from Bacillus cereus (BcII) and Aeromonas hydrophila (CphA), we found that the mononuclear enzymes are the favored targets for inhibition. By combining results from extended x-ray absorption fine structure, perturbed angular correlation of gamma-rays spectroscopy, and a study of metal ion binding, we deriv...

background and objective : carbapenems are therapeutic choice against infections caused by gram-negative bacilli including strains of acinetobacter baumannii. resistance to these antibiotics is mediated by efflux pumps, porins, pbps and ß-lactamases. the aim of this study was to determine the possibility of existence of mbls, oxas and ges-1 betalactamase genes among clinical isolates of acineto...

Antibiotic resistance among Gram-negative bacilli (GNB) is a rapidly expanding problem due to the organisms’ ability to mutate, and to acquire and transmit plasmids and other mobile genetic elements encoding resistance gene. Beta-lactamase antibiotics are among the most widely prescribed antibiotics worldwide and the emergence of resistance to these agents has resulted in a major clinical crisi...

Two models, a purely nonbonded model and a cationic dummy atom approach, were examined for the modeling of the binuclear zinc-containing IMP-1 metallo-beta-lactamase in complex with a mercaptocarboxylate inhibitor. The cationic dummy atom approach had substantial advantages as it maintained the initial, experimentally determined geometry of the metal-containing active site during molecular dyna...