Structural analyses of bacterial effectors and their mechanisms of infection

2014 Fiscal Year Final Research Report

• Project/Area Number: 24370049
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Structural biochemistry
• Research Institution: University of Hyogo
• Principal Investigator: MIZUSHIMA TSUNEHIRO 兵庫県立大学, 生命理学研究科, 教授 (90362269)
• Co-Investigator(Renkei-kenkyūsha): KIM Minsoo 東京大学, 医科学研究所, 特任准教授 (50466835)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: エフェクター / 赤痢菌 / X線結晶構造解析 / ユビキチン経路

Outline of Final Research Achievements

Pathogenic bacteria such as Shigella, EPEC, and Salmonella deliver a variety of virulence factors, called effectors, into host cells via the type III secretion system. These effectors mimic or hijack host proteins and modulate host signaling pathways to promote bacterial infection. OspI, a Shigella flexneri effector, is a glutamine deamidase that selectively deamidates the glutamine residue at position 100 in Ubc13 to a glutamic acid residue. This modification inhibits the E2 ubiquitin conjugating activity, which is required for TRAF6 activation. To elucidate the molecular mechanisms of OspI, we determined the crystal structures of OspI mutant and its complex with Ubc13. These structures provide the substrate recognition and catalytic mechanism.

Free Research Field

構造生物学