Genetic evidence for the relationship of Porphyromonas gingivalis cysteine protease and hemagglutinin activities.

Cysteine protease and hemagglutinin activities of Porphyromonas gingivalis have been implicated as virulence factors in periodontitis. In addition, a close structural relationship between these factors has been suggested. In order to examine the molecular basis for such a relationship, we constructed an isogenic mutant, G-102, of P. gingivalis 381 deficient in Arg-gingipain cysteine protease activity. The mutant displayed not only reduced protease activity but also significantly reduced hemagglutination activity compared with the wild-type strain. Therefore, this investigation provided genetic evidence for the recently proposed structural relationship between Arg-gingipain and the hemagglutinin activity of P. gingivalis strains.