7DM9

Crystal structure of FliM middle domain (51-229) from Vibro alginolyticus

7DM9 の概要

• エントリーDOI: 10.2210/pdb7dm9/pdb
• 分子名称: Flagellar motor switch protein FliM (2 entities in total)
• 機能のキーワード: flagellar motor protein, motor protein
• 由来する生物種: Vibrio alginolyticus
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 22273.84

構造登録者

Takekawa, N.,Homma, M.,Imada, K. (登録日: 2020-12-02, 公開日: 2021-07-07, 最終更新日: 2023-11-29)

主引用文献

Takekawa, N.,Nishikino, T.,Yamashita, T.,Hori, K.,Onoue, Y.,Ihara, K.,Kojima, S.,Homma, M.,Imada, K.
A slight bending of an alpha-helix in FliM creates a counterclockwise-locked structure of the flagellar motor in Vibrio.
J.Biochem., 170:531-538, 2021

PubMed Abstract: Many bacteria swim by rotating flagella. The chemotaxis system controls the direction of flagellar rotation. Vibrio alginolyticus, which has a single polar flagellum, swims smoothly by rotating the flagellar motor counterclockwise (CCW) in response to attractants. In response to repellents, the motor frequently switches its rotational direction between CCW and clockwise (CW). We isolated a mutant strain that swims with a CW-locked rotation of the flagellum, which pulls rather than pushes the cell. This CW phenotype arises from a R49P substitution in FliM, which is the component in the C-ring of the motor that binds the chemotaxis signalling protein, phosphorylated CheY. However, this phenotype is independent of CheY, indicating that the mutation produces a CW conformation of the C-ring in the absence of CheY. The crystal structure of FliM with the R49P substitution showed a conformational change in the N-terminal α-helix of the middle domain of FliM (FliMM). This helix should mediates FliM-FliM interaction. The structural models of wild type and mutant C-ring showed that the relatively small conformational change in FliMM induces a drastic rearrangement of the conformation of the FliMM domain that generates a CW conformation of the C-ring.

PubMed: 34143212
DOI: 10.1093/jb/mvab074

実験手法

X-RAY DIFFRACTION (1.71 Å)