Porphyromonas gingivalis is recognized as major periodontal pathogens, and can produce gingipain R as one of the main virulence factors. Protease activated receptor is a kind of trans-membrane protein which can recognize many pathogen associated molecular patterns, which can be activated by gingipain R, that is very important in the occurrence and development of periodontitis． This article will review the lasted researches on the composition and biological activities of gingipain R and protease activated receptor, and the role of gingipain R and protease activated receptors in periodontitis.
