Elucidation of the directional switching mechanism of the bacterial flagellar motor

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K06155
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 43040:Biophysics-related
• Research Institution: Osaka University
• Principal Investigator: Miyata Tomoko 大阪大学, 生命機能研究科, 特任准教授(常勤) (30423156)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 単粒子解析 / 電子顕微鏡 / 分子モーター

Outline of Final Research Achievements

Bacterial flagellar has a reversible rotary motor that can rotate in both counterclockwise (CCW) and clockwise (CW) direction. The switching of the motor rotation direction is controlled by the complex located at the bottom of the basal body called the C ring, constructed from switch proteins. To understand the switching mechanisms of motor rotation in detail, we analyzed the C ring structure of the wild type (CCW) and the CW- baias mutant by clectron cryomicroscopy. We obtained high-resolution density map of the C ring in the two states and built pseudo-atomic models of the C ring.

Free Research Field

構造生物学

Academic Significance and Societal Importance of the Research Achievements

本研究クライオ電子顕微鏡は近年目覚ましく発展し構造解析手法であり、生命活動を原子レベルで解明するための強力な手法である。また現在では創薬分野でも広く活用され新規薬剤の開発とうにも応用されている。我々はこの手法に着目し、複雑で巨大な生体超分子であるべん毛モーターの構造解析に成功し、この分野の進展に貢献した。