A conserved domain in type III secretion links the cytoplasmic domain of InvA to elements of the basal body
The cytoplasmic domain of Salmonella InvA shares homology to a recurring scaffold in the membrane-spanning components of the type II and type III secretion systems. Protein type III secretion systems (T3SSs) are organic nanosyringes that achieve an energy-dependent translocation of bacterial proteins through the two membranes of Gram-negative organisms. Examples include the pathogenic systems of animals, plants and symbiotic bacteria that inject factors into eukaryotic cells, and the flagellar export system that secretes flagellin. T3SSs possess a core of several membrane-associated proteins that are conserved across all known bacterial species that use this system. The Salmonella protein InvA is one of the most highly conserved proteins of this core of critical T3SS components. The crystal structure of a C-terminal domain of InvA reveals an unexpected homology to domains that have been repeatedly found as building blocks of other elements of the T3SS apparatus. This suggests the surprising hypothesis that evolution has produced a significant component of the apparatus structure through a series of gene-duplication and gene-rearrangement events.
- OSTI ID:
- 22347913
- Journal Information:
- Acta Crystallographica. Section D: Biological Crystallography, Vol. 66, Issue Pt 6; Other Information: PMCID: PMC2879356; PMID: 20516623; PUBLISHER-ID: ea5120; OAI: oai:pubmedcentral.nih.gov:2879356; Copyright (c) Lilic et al. 2010; This is an open-access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0907-4449
- Country of Publication:
- Denmark
- Language:
- English
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