Structural basis of FliG-FliM interaction in Helicobacter pylori
Publication in refereed journal


摘要FliG and FliM are switch proteins that regulate the rotation and switching of the flagellar motor. Several assembly models for FliG and FliM have recently been proposed; however, it remains unclear whether the assembly of the switch proteins is conserved among different bacterial species. We applied a combination of pull-down, thermodynamic and structural analyses to characterize the FliMFliG association from the mesophilic bacterium Helicobacter pylori.FliM binds to FliG with micromolar binding affinity, and their interaction is mediated through the middle domain of FliG (FliGM), which contains the EHPQR motif. Crystal structures of the middle domain of H.pyloriFliM (FliMM) and FliGMFliMM complex revealed that FliG binding triggered a conformational change of the FliM 3-1 loop, especially Asp130 and Arg144. We furthermore showed that various highly conserved residues in this region are required for FliMFliG complex formation. Although the FliMFliG complex structure displayed a conserved binding mode when compared with Thermotogamaritima, variable residues were identified that may contribute to differential binding affinities across bacterial species. Comparison of the thermodynamic parameters of FliGFliM interactions between H.pylori and Escherichia coli suggests that molecular basis and binding properties of FliM to FliG is likely different between these two species.
著者Lam KH, Lam WWL, Wong JYK, Chan LC, Kotaka M, Ling TKW, Jin DY, Ottemann KM, Au SWN
期刊名稱Molecular Microbiology
詳細描述To ORKTS: Author WONG Yan Kit is a former final year project student in Biochemistry Programme. However, his name cannot be found in the database.
出版社Wiley: 12 months
頁次798 - 812
Web of Science 學科類別Biochemistry & Molecular Biology; BIOCHEMISTRY & MOLECULAR BIOLOGY; Microbiology; MICROBIOLOGY

上次更新時間 2020-27-10 於 00:32