Julien Bergeron

Structural Studies of Nanomachines 

Architecture and assembly of the T3SS injectisome

Gram-negative bacteria are a family of pathogens including E.coli, Salmonella, Shigella, Pseudomonas aeruginosa, and Yersinia pestis. These bacteria are responsible for a wide range of diseases, from gastro-intestinal infections to the plague. A common trait shared by these bacteria is their capacity to inject toxins directly inside the cells of infected individuals, thanks to a syringe-shaped "nano-machine" called the Type 3 Secretion System (T3SS) injectisome. These toxins leads to modifications of the host cell, allowing the bacteria to replicate efficiently and/or to evade the immune system, and are necessary to establish an infection. As a consequence, preventing the injectisome from performing its function, i.e. injecting the toxins, would effectively prevent the bacteria from causing a disease. As such, the injectisome is an important potential target for the development of novel therapeutics against bacterial infection.

Related publications:

Worrall LJ, Hong C, Vuckovic M, Bergeron JRC, Majewski DD, Huang RK, Spreter T, Finlay BB, Yu Z, Strynadka NCJ. Near-atomic-resolution cryo-EM analysis of the Salmonella T3S injectisome basal body. Nature 2016

Bergeron JR, Fernández L, Wasney GA, Vuckovic M, Reffuveille F, Hancock RE, Strynadka NC. The Structure of a T3SS Ruler Protein Suggests a Molecular Mechanism for Needle Length Sensing. Journal of Biological Chemistry 2015.

Bergeron JR, Worrall LJ, De S, Sgourakis NG, Cheung AH, Lameignere E, Okon M, Wasney GA, Baker D, McIntosh LP, Strynadka NC. The Modular Structure of the Inner-Membrane Ring Component PrgK Facilitates Assembly of the Type III Secretion System Basal Body. Structure 2014.

Worrall LJ, Bergeron JRC, Strynadka NCJ. Type III secretion systems. In: Escherichia coli: Pathotypes and Principles of Pathogenesis, 2nd Edition. Edited by Michael Donnenberg. Academic Press 2013.

Bergeron JR, Worrall LJ, Sgourakis NG, DiMaio F, Pfuetzner RA, Felise HB, Vuckovic M, Yu AC, Miller SI, Baker D, Strynadka NC. A refined model of the prototypical Salmonella SPI-1 T3SS basal body reveals the molecular basis for its assembly. PLoS Pathogens 2013.

Thanabalasuriar A, Bergeron J, Gillingham A, Mimee M, Thomassin JL, Strynadka N, Kim J, Gruenheid S. Sec24 interaction is essential for localization and virulence-associated function of the bacterial effector protein NleA. Cell Microbiology 2012.


Latest News

22/12/16 - Our cryo-EM structure of the T3SS basal body has been published in the journal Nature: goo.gl/9grdaT

02/12/16 - I am recruiting a PhD student to join my (forthcoming) lab in the Department of Molecular Biology and Biotechnology at the University of Sheffield, UK. Interested candidates should apply here.

30/10/16 - I will be giving a talk at the Sheffield Imagine: Imaging Life launch symposium, in January 2017: http://goo.gl/bc72LW