INDUCIBLE EXPRESSION OF A PORPHYROMONAS-GINGIVALIS W83 MEMBRANE-ASSOCIATED PROTEASE

The Tpr protease of Porphyromonas gingivalis W83 is a membrane-associa ted enzyme capable of hydrolyzing a chromogenic bacterial collagenase substrate. An isogenic mutant lacking a functional tpr gene had a grea tly reduced ability to hydrolyze the collagenase substrate. Activity w as restored to the tpr mutant by introducing a shuttle plasmid contain ing the tpr gene. Expression of the gene is induced by nutrient limita tion, as shown by enzymatic and Northern analyses.