Demonstration of extracellular proteolytic enzymes from Legionella species strains by using synthetic chromogenic peptide substrates.

Crude concentrates of extracellular proteases from strains belonging to species within the genus Legionella were examined for their effect upon synthetic chromogenic tri- and tetrapeptides. For the species L. pneumophila, similar and reproducible substrate degradation patterns were found. Strains from the other Legionella species produced proteases with dissimilar proteolytic patterns, which were all distinct from those of the L. pneumophila proteases.