Evolution of extended-spectrum beta-lactamase-producing Escherichia coli

Escherichia coli belonging to sequence type ST131 constitute a globally-distributed pandemic lineage that causes multidrug-resistant extra-intestinal infections. ST131 E. coli frequently produce extended-spectrum beta-lactamases (ESBLs), which confer resistance to many beta-lactam antibiotics and make infections difficult to treat. We sequenced the genomes of clinical ESBL-producing E. coli isolates belonging to the ST131 lineage from patients at the University of Pittsburgh Medical Center (UPMC).