Induction of cell lysis in Escherichia coli: cooperative effect of nocardicin A and mecillinam.

Nocardicin A and mecillinam are two beta-lactam antibiotics with poor bacteriolytic activity against Escherichia coli. However, the combined use of these drugs resulted in the induction of a fast lytic response in E. coli cells. For this cooperative effect to take place, the formation of a complex between penicillin-binding protein 2 and mecillinam is apparently necessary. This suggests that penicillin-binding protein 2 might be actively involved in the response of E. coli to bacteriolytic beta-lactam antibiotics.