Structural study by electron cryomicroscopy of the MotA/MotB flagellar stator of Leptospira interrogans

• Grant number: 24/10763-6
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: January 01, 2025
• End date: December 31, 2029
• Field of knowledge: Biological Sciences - Biochemistry - Chemistry of Macromolecules
• Principal Investigator: Cristiane Rodrigues Guzzo Carvalho
• Grantee: Cauê Augusto Boneto Gonçalves
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 21/10577-0 - Biology of Bacteria and Bacteriophages Research Center, AP.CEPID
• Associated scholarship(s): 25/05589-0 - Optimization of Purification and Cryo-EM Structural Determination of the Flagellar Stator MotAB-FliL Complex in Leptospira interrogans, BE.EP.DD

Abstract

The bacterial flagellum is a macromolecular complex essential for the motility and virulence of several bacteria. In spirochetes, such as Leptospira interrogans, the flagellum has a unique structure and location, being periplasmic and presenting a specific component called "P-collar" (FlbD). The FliL protein also plays an important role in generating torque in the flagellar motor, interacting with MotA and MotB proteins. This project aims to investigate the structure and function of the flagellar stator protein complex of L. interrogans, formed by FlbD, MotA, MotB, and FliL proteins, using cryo-electron microscopy (cryo-EM) techniques. Furthermore, it is intended to study the interaction of the stator with FliG and YcgR proteins, which are important for torque generation and bacterial motility. The elucidation of the structure and function of the flagellar stator of L. interrogans will contribute to the understanding of the molecular mechanisms involved in the motility and pathogenicity of spirochetes, paving the way for understanding bacterial motility and the mechanism of flagellar stators, as well as the function of some proteins that remain an enigma to knowledge.