Beta‐lactamases and bacterial resistance to antibiotics

Abstract

Summary: The efficiency of β‐lactam antibiotics, which are among our most useful chemotherapeutic weapons, is continuously challenged by the emergence of resistant bacterial strains. This is most often due to the production of β‐lactamases by the resistant cells. These enzymes inactivate the antibiotics by hydrolysing the β‐lactam amide bond. The elucidation of the structures of some β‐lactamases by X‐ray crystallography has provided precious insights into their catalytic mechanisms and revealed unsuspected similarities with the DD‐transpeptidases, the bacterial enzymes which constitute the lethal targets of β‐lactams. Despite numerous kinetic, structural and site‐directed mutagenesis studies, we have not completely succeeded in explaining the diversity of the specificity profiles of β‐lactamases and their surprising catalytic power. The solutions to these problems represent the cornerstones on which better antibiotics can be designed, hopefully on a rational basis.