A mechanism by which a bacterial outer membrane lipoprotein transmits cell surface stress information to an inner membrane component of a two-component regulatory system

2016 Fiscal Year Final Research Report

• Project/Area Number: 25440176
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Genetics/Chromosome dynamics
• Research Institution: Saitama University
• Principal Investigator: HARA Hiroshi 埼玉大学, 理工学研究科, 准教授 (00173071)
• Research Collaborator: MATSUMOTO Kouji 埼玉大学, 理工学研究科, 名誉教授
• Project Period (FY): 2013-04-01 – 2017-03-31
• Keywords: 大腸菌 / 外膜リポタンパク質 / 二成分制御系 / 細胞表層ストレス / タンパク質間相互作用 / BiFC / ヒスチジンキナーゼ / 負の制御因子

Outline of Final Research Achievements

An outer membrane lipoprotein RcsF is an essential component of the Rcs phosphorelay signal transduction system of Escherichia coli. Mislocalization of RcsF to the periplasm or to the cytoplasmic membrane leads to high activation of the Rcs system, suggesting that RcsF functions by interacting with the cytoplasmic membrane component(s) of the system. This is consistent with the report that RcsF interacts with the periplasmic domain of the inner membrane protein YrfF (YrfFperi), a negative regulator of the system. We show that RcsF also interacts with the periplasmic domain of the inner membrane histidine kinase RcsC (RcsCperi). When RcsCperi was secreted to the periplasm, it titrated RcsF’s activating effect. A bimolecular fluorescence complementation (BiFC) experiment showed interaction of RcsF with RcsCperi as well as with YrfFperi. We conclude that RcsF interacts with the periplasmically exposed region of RcsC as well as with that of YrfF in activating the system.

Free Research Field

分子生物学