Supermolecule structure and mechanism of a novel bacterial protein secretion system, type IX secretion system

2015 Fiscal Year Final Research Report

• Project/Area Number: 25293375
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Morphological basic dentistry
• Research Institution: Nagasaki University
• Principal Investigator: NAKAYAMA Koji 長崎大学, 医歯薬学総合研究科(歯学系), 教授 (80150473)
• Co-Investigator(Kenkyū-buntansha): IMADA Katsumi 大阪大学, 理学研究科, 教授 (40346143)
• Co-Investigator(Renkei-kenkyūsha): NAITO Mariko 長崎大学, 医歯薬学総合研究科(歯学系), 准教授 (20244072) ; SHOJI Mikio 長崎大学, 医歯薬学総合研究科(歯学系), 助教 (10336175) ; SATO Keiko 長崎大学, 医歯薬学総合研究科(歯学系), 助教 (70410579) ; YUKITAKE Hideharu 長崎大学, 医歯薬学総合研究科(歯学系), 技術職員 (30380984)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 歯周病 / タンパク分泌 / 細菌

Outline of Final Research Achievements

We found a novel secretion system, Por secretion system in the periodontal pathogen Porphyromonas gingivalis, which is now called the type IX secretion system (T9SS). We found a ring-shaped structure consisting of PorK and PorN in the membrane fraction of P. gingivalis. We found with mutant study that Tannerella forsythia, Prvotella intermedia and Capnocytophaga ochracea have functional T9SSs. T9SSs are not limited to the oral bacteria but extend to other bacteria belonging to the phylum Bacteroidetes such as Flavobacterium johnsoniae and Cytophaga hutchinsonii known as gliding bacteria. Gliding motility of the bacteria is tightly associated with T9SS. We propose a helical loop track model for gliding motility of Bacteroidetes phylum bacteria.

Free Research Field

口腔病原微生物学