Geographical evolution of the CTX-M ß-lactamase – an update

Abstract

The CTX-M- type extended spectrum -lactamases (ESBLs) that preferentially hydrolyze cefotaxime are emerging globally and comprise of more than 50 enzymes. The emergence of novel CTX-M - lactamases in several countries is noted as opposed to the transfer of established CTX-M genes from one country to another, suggestive of a de novo dissemination of CTX-M genes.