Characterization of a New Extended-Spectrum β-Lactamase (TEM-87) Isolated in Proteus mirabilis during an Italian Survey

ABSTRACT

A new natural TEM derivative, named TEM-87, was identified in a Proteus mirabilis isolate from an Italian hospital. Compared to TEM-1, TEM-87 contains the following mutations: E104K, R164C, and M182T. Kinetic analysis of TEM-87 revealed extended-spectrum activity against oxyimino cephalosporins (preferentially ceftazidime) and aztreonam. Expression of bla_TEM-87 in Escherichia coli decreased the host susceptibility to these drugs.