SQ 26,180, a novel monobactam. I. Taxonomy, fermentation and biological properties.

Abstract
Strains of Chromobacterium violaceum, isolated from various environments, produce a novel monocyclic .beta.-lactam antibiotic. The antibiotic, SQ 26,180 was weakly active against gram-positive and gram-negative bacteria with the exception of mutants hypersensitive to .beta.-lactam antibiotics. The compound was highly stable to .beta.-lactamases and acted as an inhibitor of the P99 enzyme from Enterobacter cloacae. SQ 26,180 showed affinity for penicillin-binding proteins 1a, 4 and 5/6 of Escherichia coli and inhibited R61 DD-carboxypeptidase.