Susceptibility of Moxalactam to β-Lactamase

Abstract

Moxalactam is not significantly susceptible to the majority of β-lactamases produced by bacteria of clinical relevance. However, two types of enzyme-PSE2 and PSE3-from Pseudomonas aeruginosa can hydrolyze this antibiotic at a significant rate. In this respect moxalactam is similar to 7-α-methoxy cephem compounds, such as cefoxitin, which are also susceptible to these enzymes. Moxalactam, like other β-lactam antibiotics having an acid function in the side chain, is a potent inhibitor of the cephalosporinase from Enterobacter cloacae (type Ia β-lactamase).