An inventory of peptide hydrolases and arylamidases in Flavobacterium II b

The determination of the number and the specificity of peptide hydrolases and arylamidases present in a cell‐free sonicate from Flavobacterium II b, a species phenotypically similar to Flavobacterium balustinum , involved polyacrylamide gel electrophoresis and coloration of end products or staining procedures using diazotation reactions. Only substrates with L‐configuration amino acids and dipeptides with an unsubstituted R N ‐group were cleaved. One protein band, that was able to hydrolyse skimmed milk agar, was observed but carboxypeptidase and endopep‐tidase (chymotrypsin and trypsin activities) were absent. Zymograms exhibited ary‐lamidase, dipeptidase and tripeptidase activities. Results underline the distinction between the L‐leucine aminopeptidase and the L‐leucylarylamidase.