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4nkh

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Revision as of 18:37, 24 December 2014

Crystal structure of SspH1 LRR domain

Structural highlights

4nkh is a 6 chain structure with sequence from Salt1. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Related:	4nkg
Gene:	sspH1, STM14_1483 (SALT1)
Resources:	FirstGlance, OCA, RCSB, PDBsum

Function

[SSPH1_SALT1] Effector proteins function to alter host cell physiology and promote bacterial survival in host tissues. This protein is an E3 ubiquitin ligase that interferes with host's ubiquitination pathway. Can ubiquitinate both ubiquitin and host PKN1. Down-modulates production of host proinflammatory cytokines by inhibiting NF-kappa-B-dependent gene expression, probably via interaction with PKN1.^[1] ^[2] ^[3] ^[4]

Publication Abstract from PubMed

IpaH proteins are bacterial-specific E3 enzymes that function as T3SS effectors in Salmonella, Shigella, and other gram-negative bacteria. IpaH enzymes recruit host substrates for ubiquitination via an LRR domain, which can inhibit the catalytic domain in the absence of substrate. The basis for substrate recognition and the alleviation of autoinhibition upon substrate binding is unknown. Here we report the X-ray structure of Salmonella SspH1 in complex with human PKN1. The LRR domain of SspH1 interacts specifically with the HR1b coiled-coil sub-domain of PKN1 in manner that sterically displaces the catalytic domain from the LRR domain, and thereby activates catalytic function. SspH1 catalyzes the ubiquitination and proteasome-dependent degradation of PKN1 in cells, which attenuates androgen receptor responsiveness but not NF-kappaB activity. These regulatory features are conserved in other IpaH-substrate interactions. Our results explain the mechanism whereby substrate recognition and enzyme autoregulation are coupled in this class of bacterial effector proteins.

Structure of an SspH1-PKN1 complex reveals the basis for host substrate recognition and mechanism of activation for a bacterial E3 ubiquitin ligase.,Keszei AF, Tang X, McCormick C, Zeqiraj E, Rohde JR, Tyers M, Sicheri F Mol Cell Biol. 2013 Nov 18. PMID:24248594^[5]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Miao EA, Scherer CA, Tsolis RM, Kingsley RA, Adams LG, Baumler AJ, Miller SI. Salmonella typhimurium leucine-rich repeat proteins are targeted to the SPI1 and SPI2 type III secretion systems. Mol Microbiol. 1999 Nov;34(4):850-64. PMID:10564523
↑ Haraga A, Miller SI. A Salmonella enterica serovar typhimurium translocated leucine-rich repeat effector protein inhibits NF-kappa B-dependent gene expression. Infect Immun. 2003 Jul;71(7):4052-8. PMID:12819095
↑ Haraga A, Miller SI. A Salmonella type III secretion effector interacts with the mammalian serine/threonine protein kinase PKN1. Cell Microbiol. 2006 May;8(5):837-46. PMID:16611232 doi:http://dx.doi.org/10.1111/j.1462-5822.2005.00670.x
↑ Rohde JR, Breitkreutz A, Chenal A, Sansonetti PJ, Parsot C. Type III secretion effectors of the IpaH family are E3 ubiquitin ligases. Cell Host Microbe. 2007 Mar 15;1(1):77-83. PMID:18005683 doi:10.1016/j.chom.2007.02.002
↑ Keszei AF, Tang X, McCormick C, Zeqiraj E, Rohde JR, Tyers M, Sicheri F. Structure of an SspH1-PKN1 complex reveals the basis for host substrate recognition and mechanism of activation for a bacterial E3 ubiquitin ligase. Mol Cell Biol. 2013 Nov 18. PMID:24248594 doi:http://dx.doi.org/10.1128/MCB.01360-13

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 See Also
5 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/4nkh"

@@ Line 7: / Line 7: @@
 <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4nkh FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4nkh OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4nkh RCSB], [http://www.ebi.ac.uk/pdbsum/4nkh PDBsum]</span></td></tr>
 </table>
+== Function ==
+[[http://www.uniprot.org/uniprot/SSPH1_SALT1 SSPH1_SALT1]] Effector proteins function to alter host cell physiology and promote bacterial survival in host tissues. This protein is an E3 ubiquitin ligase that interferes with host's ubiquitination pathway. Can ubiquitinate both ubiquitin and host PKN1. Down-modulates production of host proinflammatory cytokines by inhibiting NF-kappa-B-dependent gene expression, probably via interaction with PKN1.<ref>PMID:10564523</ref> <ref>PMID:12819095</ref> <ref>PMID:16611232</ref> <ref>PMID:18005683</ref>
 <div style="background-color:#fffaf0;">
 == Publication Abstract from PubMed ==

4nkh

From Proteopedia

Revision as of 18:37, 24 December 2014

Crystal structure of SspH1 LRR domain

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

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