We constructed a phylogenetic analysis of class A beta-lactamases and found that the blaCTX-Ms have been mobilized to plasmids approximately 10 times more frequently than other class A beta-lactamases. We also found that the blaCTX-Ms are descended from a common ancestor that was incorporated in ancient times into the chromosome of the ancestor of Kluyvera species through horizontal transfer. C...

Two ampicillin-resistant (Amp(r)) isolates of Vibrio harveyi, W3B and HB3, were obtained from the coastal waters of the Indonesian island of Java. Strain W3B was isolated from marine water near a shrimp farm in North Java while HB3 was from pristine seawater in South Java. In this study, novel beta-lactamase genes from W3B (bla(VHW-1)) and HB3 (bla(VHH-1)) were cloned and their nucleotide seque...

New antibiotic regimens are needed for the treatment of multidrug-resistant tuberculosis. Mycobacterium tuberculosis has a thick peptidoglycan layer, and the penicillin-binding proteins involved in its biosynthesis are inhibited by clinically relevant concentrations of beta-lactam antibiotics. beta-Lactamase production appears to be the major mechanism by which M. tuberculosis expresses beta-la...

A new cephalosporin with a highly reactive beta-lactam ring was found to give an immediate color change in the presence of beta-lactamases from many bacteria, including staphylococci, Bacillus species, Enterobacteriaceae, and Pseudomonas. The reaction is confined to organisms producing beta-lactamases, but it is sufficiently sensitive to indicate the presence of this enzyme is small amounts in ...

In this review, we summarize the current “state of art” carbapenem antibiotics and their role in our antimicrobial armamentarium. Among beta-lactams currently available, carbapenems are unique because they relatively resistant to hydrolysis by most beta-lactamases. Herein, described cost effectiveness, safety, advantages as compared other antibiotics. We also highlight important features that p...

Enterobacteriaceae clinical strains that produce the class A carbapenem-hydrolysing enzyme KPC (Klebsiella pneumoniae carbapenemase) are increasingly reported worldwide, and are already endemic in North and South America, China, Israel and Greece. The accurate detection of KPC enzymes is of utmost importance for containing the global spread of KPC producers. Currently, the detection of putative...

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