Bacteria have evolved several secretion machineries to bring about transport of various virulence factors, nutrients, nucleic acids and cell-surface appendages that are essential for their pathogenesis. T4S (Type IV secretion) systems are versatile secretion systems found in various Gram-negative and Gram-positive bacteria and in few archaea. They are large multisubunit translocons secreting a diverse array of substrates varying in size and nature from monomeric proteins to nucleoprotein complexes. T4S systems have evolved from conjugation machineries and are implicated in antibiotic resistance gene transfer and transport of virulence factors in Legionella pneumophila causing Legionnaires’ disease, Brucella suis causing brucellosis and Helicobacter pylori causing gastroduodenal diseases. The best-studied are the Agrobacterium tumefaciens VirB/D4 and the Escherichia coli plasmid pKM101 T4S systems. Recent structural advances revealing the cryo-EM (electron microscopy) structure of the core translocation assembly and high-resolution structure of the outer-membrane pore of T4S systems have made paradigm shifts in the understanding of T4S systems. The present paper reviews the advances made in biochemical and structural studies and summarizes our current understanding of the molecular architecture of this mega-assembly.
Skip Nav Destination
Article navigation
February 2013
-
Cover Image
Cover Image
- PDF Icon PDF LinkFront Matter
- PDF Icon PDF LinkTable of Contents
Conference Article|
January 29 2013
Type IV secretion machinery: molecular architecture and function
Vidya Chandran
Vidya Chandran
1
1Division of Molecular Biosciences, Centre for Structural Biology, Imperial College London, South Kensington, London SW7 2AZ, U.K.
1email[email protected]
Search for other works by this author on:
Publisher: Portland Press Ltd
Received:
November 07 2012
Online ISSN: 1470-8752
Print ISSN: 0300-5127
© The Authors Journal compilation © 2013 Biochemical Society
2013
Biochem Soc Trans (2013) 41 (1): 17–28.
Article history
Received:
November 07 2012
Citation
Vidya Chandran; Type IV secretion machinery: molecular architecture and function. Biochem Soc Trans 1 February 2013; 41 (1): 17–28. doi: https://doi.org/10.1042/BST20120332
Download citation file:
Sign in
Don't already have an account? Register
Sign in to your personal account
You could not be signed in. Please check your email address / username and password and try again.
Could not validate captcha. Please try again.
Biochemical Society Member Sign in
Sign InSign in via your Institution
Sign in via your InstitutionGet Access To This Article
Get Email Alerts
Open Access for all
We offer compliant routes for all authors from 2025. With library support, there will be no author nor reader charges in 5 journals. Check here |
![]() |