Summary: V antigen (LcrV) protein
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the structure of yersinia pestis v-antigen, an essential virulence factor and mediator of immunity against plague
In molecular biology, LcrV is a protein found in Yersinia pestis and several other bacterial species. It forms part of the Yersinia pestis virulence protein factors that also includes all Yop's, this used to stand for Yersinia outer protein, but the name has been kept out of convention. LcrV's main function is not actually known, but it is essential for the production of other Yops.
The type III secretion system of Gram-negative bacteria is used to transport virulence factors from the pathogen directly into the host cell and is only triggered when the bacterium comes into close contact with the host. Effector proteins secreted by the type III system do not possess a secretion signal, and are considered unique because of this. Yersinia spp. secrete effector proteins called YopB and YopD that facilitate the spread of other translocated proteins through the type III needle and the host cell cytoplasm. In turn, the transcription of these moieties is thought to be regulated by another gene, lcrV, found on the Yops virulon that encodes the entire type III system. The product of this gene, LcrV protein, also regulates the secretion of YopD through the type III translocon, and itself acts as a protective "V" antigen for Yersinia pestis, the causative agent of plague.
A homologue of the Y. pestis LcrV protein, PcrV, has been found in Pseudomonas aeruginosa, an opportunistic pathogen. In vivo studies using mice found that immunisation with the protein protected burned animals from infection by P. aeruginosa, and enhanced survival. In addition, it is speculated that PcrV determines the size of the needle pore for type III secreted effectors.
LcrV is a multifunctional protein that has been shown to act at the level of secretion control by binding the Ysc inner-gate protein LcrG and to modulate the host immune response by altering cytokine production. LcrV is also necessary for full induction of low-calcium response (LCR) stimulon virulence gene transcription.
- Hueck CJ (June 1998). "Type III protein secretion systems in bacterial pathogens of animals and plants". Microbiol. Mol. Biol. Rev. 62 (2): 379–433. PMC . PMID 9618447.
- Williams AW, Straley SC (January 1998). "YopD of Yersinia pestis plays a role in negative regulation of the low-calcium response in addition to its role in translocation of Yops". J. Bacteriol. 180 (2): 350–8. PMC . PMID 9440524.
- Sarker MR, Neyt C, Stainier I, Cornelis GR (March 1998). "The Yersinia Yop virulon: LcrV is required for extrusion of the translocators YopB and YopD". J. Bacteriol. 180 (5): 1207–14. PMC . PMID 9495760.
- DeBord KL, Lee VT, Schneewind O (August 2001). "Roles of LcrG and LcrV during type III targeting of effector Yops by Yersinia enterocolitica". J. Bacteriol. 183 (15): 4588–98. doi:10.1128/JB.183.15.4588-4598.2001. PMC . PMID 11443094.
- Matson JS, Nilles ML (September 2001). "LcrG-LcrV interaction is required for control of Yops secretion in Yersinia pestis". J. Bacteriol. 183 (17): 5082–91. doi:10.1128/jb.183.17.5082-5091.2001. PMC . PMID 11489861.
- Holder IA, Neely AN, Frank DW (September 2001). "PcrV immunization enhances survival of burned Pseudomonas aeruginosa-infected mice". Infect. Immun. 69 (9): 5908–10. doi:10.1128/iai.69.9.5908-5910.2001. PMC . PMID 11500471.
- Nilles ML, Fields KA, Straley SC (1998). "The V antigen of Yersinia pestis regulates Yop vectorial targeting as well as Yop secretion through effects on YopB and LcrG.". J Bacteriol. 180 (13): 3410–20. PMC . PMID 9642196.
- Skrzypek E, Straley SC (1995). "Differential effects of deletions in lcrV on secretion of V antigen, regulation of the low-Ca2+ response, and virulence of Yersinia pestis.". J Bacteriol. 177 (9): 2530–42. PMC . PMID 7730287.
- Salyers, Abigail & Whitt, Dixie; Bacterial Pathogenesis: A Molecular Approach, AMS Press
- Biological Weapons Defense: Infectious Diseases and Counterbioterrorism, Humana Press
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V antigen (LcrV) protein Provide feedback
Yersinia pestis, the aetiologic agent of plague, secretes a set of environmentally regulated, plasmid pCD1-encoded virulence proteins termed Yops and V antigen (LcrV) by a type III secretion mechanism. LcrV is a multifunctional protein that has been shown to act at the level of secretion control by binding the Ysc inner-gate protein LcrG and to modulate the host immune response by altering cytokine production. LcrV is also necessary for full induction of low-calcium response (LCR) stimulon virulence gene transcription. Family members are not confined to Yersinia pestis [1,2].
Nilles ML, Fields KA, Straley SC; , J Bacteriol 1998;180:3410-3420.: The V antigen of Yersinia pestis regulates Yop vectorial targeting as well as Yop secretion through effects on YopB and LcrG. PUBMED:9642196 EPMC:9642196
Skrzypek E, Straley SC; , J Bacteriol 1995;177:2530-2542.: Differential effects of deletions in lcrV on secretion of V antigen, regulation of the low-Ca2+ response, and virulence of Yersinia pestis. PUBMED:7730287 EPMC:7730287
External database links
This tab holds annotation information from the InterPro database.
InterPro entry IPR005413
The type III secretion system of Gram-negative bacteria is used to transport virulence factors from the pathogen directly into the host cell [PUBMED:9618447] and is only triggered when the bacterium comes into close contact with the host. Effector proteins secreted by the type III system do not possess a secretion signal, and are considered unique because of this. Yersinia spp. secrete effector proteins called YopB and YopD that facilitate the spread of other translocated proteins through the type III needle and the host cell cytoplasm [PUBMED:9440524]. In turn, the transcription of these moieties is thought to be regulated by another gene, lcrV, found on the Yops virulon that encodes the entire type III system [PUBMED:9495760]. The product of this gene, LcrV protein, also regulates the secretion of YopD through the type III translocon [PUBMED:11443094], and itself acts as a protective "V" antigen for Yersinia pestis, the causative agent of plague [PUBMED:11489861].
Recently, a homologue of the Y. pestis LcrV protein (PcrV) was found in Pseudomonas aeruginosa, an opportunistic pathogen. In vivo studies using mice found that immunisation with the protein protected burned animals from infection by P. aeruginosa, and enhanced survival. In addition, it is speculated that PcrV determines the size of the needle pore for type III secreted effectors [PUBMED:11500471].
The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.
|Cellular component||extracellular region (GO:0005576)|
|Biological process||pathogenesis (GO:0009405)|
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1Cannot generate PP/Heatmap alignments for seeds; no PP data available
Key: available, not generated, — not available.
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|Seed source:||Pfam-B_6155 (release 7.5)|
|Author:||Waterfield DI, Finn RD|
|Number in seed:||2|
|Number in full:||11|
|Average length of the domain:||227.50 aa|
|Average identity of full alignment:||35 %|
|Average coverage of the sequence by the domain:||48.97 %|
|HMM build commands:||
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 26740544 -E 1000 --cpu 4 HMM pfamseq
|Family (HMM) version:||11|
|Download:||download the raw HMM for this family|
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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the LcrV domain has been found. There are 2 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein seqence.
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