Production of beta-lactamase by non-streptomyces Actinomycetales

Supernatants and whole cells from fermentation broths of Micromonospora, Nocardia, Oerskovia, and other genera of the Actinomycetales were examined for the presence of beta-lactamase activity by using the chromogenic cephalosporin 87/312. Nearly 60% of the 250 isolates examined produced detectable levels of beta-lactamase. All enzyme preparations were active over a range of pH values from 6.5 to 8.2, with maximum activity occurring between 7.0 and 7.8. The preparations varied in their stability at 60 degrees C. An examination of selected enzyme preparations revealed a similarity between substrate specificities of the non-Streptomyces Actinomycetales and gram-negative-bacterial beta-lactamases.