Regulation of proteolytic enzyme production by Aeromonas proteolytica. I. Extracellular endopeptidase.

Abstract

The production of extracellular endopeptidase by Aeromonas proteolytica Merkel et al. was found to be influenced by a number of nutritional factors. An inverse relationship existed between endopeptidase synthesis and growth in media containing increasing quantities of asparagine. This effect was accentuated by the individual addition of glycerol, glucose, sucrose, or acetate as supplemental carbon sources. The addition of small quantities of complex mixtures of peptides to growth media containing either acid-hydrolyzed casein or asparagine as the organic component greatly stimulated endopeptidase synthesis. The data suggest that endopeptidase synthesis is repressed when A. proteolytica is grown in the presence of certain individual amino acids, that glycerol and some other easily metabolized compounds cause catabolite repression of endopeptidase synthesis, and that endopeptidase production is stimulated by peptides of unknown identity.