Study of a novel enzymatic group of dipeptidyl peptidases and their cellular localization

2015 Fiscal Year Final Research Report

• Project/Area Number: 25462894
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Functional basic dentistry
• Research Institution: Nagasaki University
• Principal Investigator: OHARA-NEMOTO Yuko 長崎大学, 医歯薬学総合研究科(歯学系), 准教授 (10164667)
• Co-Investigator(Kenkyū-buntansha): NEMOTO Takayuki K. 長崎大学, 医歯薬学総合研究科(歯学系), 教授 (90164665) ; KIMURA Shigenobu 岩手医科大学, 歯学部, 教授 (10177917)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: Porphyromonas gingivalis / ジペプチジルペプチダーゼ / アミノ酸代謝 / ペリプラズム / 歯周病

Outline of Final Research Achievements

We examined enzymatic activity and cellular localization of a group of dipeptidyl peptidases (DPP) in a periodontopathic bacterium, Porphyromonas gingivalis. This study revealed that DPP5, which had been discovered in fungi, was expressed in the bacterium, and that a novel peptidase, acylpeptidyl oligopeptidase (AOP), was identified. Ortholog search demonstrated wide spreading of the two exopeptidases from bacteria, archea to eukaryote. DPP5 cleaves X-Ala dipeptides from the N-terminus of oligopeptides and AOP liberates di- and tri-peptides from N-terminally blocked ones. Both peptidases were expressed in the periplasmic space of the bacterium. Consequently, we proposed that dipeptide-producing exopeptidases including DPP4, DPP5, DPP7, DPP11 and AOP are crucial for the growth and pathogenicity of P. gingivalis.

Free Research Field

口腔生化学