Editor: William Margolin
Protein secretion and outer membrane assembly in Alphaproteobacteria
Article first published online: 28 AUG 2008
Journal compilation © 2008 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. No claim to original US government works
FEMS Microbiology Reviews
Volume 32, Issue 6, pages 995–1009, November 2008
How to Cite
Gatsos, X., Perry, A. J., Anwari, K., Dolezal, P., Wolynec, P. P., Likić, V. A., Purcell, A. W., Buchanan, S. K. and Lithgow, T. (2008), Protein secretion and outer membrane assembly in Alphaproteobacteria. FEMS Microbiology Reviews, 32: 995–1009. doi: 10.1111/j.1574-6976.2008.00130.x
- Issue published online: 10 OCT 2008
- Article first published online: 28 AUG 2008
- Received 18 April 2008; revised 23 June 2008; accepted 18 July 2008.First published online 28 August 2008.
- outer membrane assembly;
- membrane structure;
- β-barrel proteins;
The assembly of β-barrel proteins into membranes is a fundamental process that is essential in Gram-negative bacteria, mitochondria and plastids. Our understanding of the mechanism of β-barrel assembly is progressing from studies carried out in Escherichia coli and Neisseria meningitidis. Comparative sequence analysis suggests that while many components mediating β-barrel protein assembly are conserved in all groups of bacteria with outer membranes, some components are notably absent. The Alphaproteobacteria in particular seem prone to gene loss and show the presence or absence of specific components mediating the assembly of β-barrels: some components of the pathway appear to be missing from whole groups of bacteria (e.g. Skp, YfgL and NlpB), other proteins are conserved but are missing characteristic domains (e.g. SurA). This comparative analysis is also revealing important structural signatures that are vague unless multiple members from a protein family are considered as a group (e.g. tetratricopeptide repeat (TPR) motifs in YfiO, β-propeller signatures in YfgL). Given that the process of the β-barrel assembly is conserved, analysis of outer membrane biogenesis in Alphaproteobacteria, the bacterial group that gave rise to mitochondria, also promises insight into the assembly of β-barrel proteins in eukaryotes.