This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.

Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.

4uey

From Proteopedia

(Difference between revisions)

Jump to: navigation, search

Revision as of 11:12, 26 February 2020

Structure of the periplasmic domain PhoQ double mutant (W104C-A128C)

Structural highlights

4uey is a 3 chain structure with sequence from "bacillus_cholerae-suis"_smith_1894 "bacillus cholerae-suis" smith 1894. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

[PHOQ_SALTY] Member of the two-component regulatory system PhoP/PhoQ which regulates the expression of genes involved in virulence, adaptation to acidic and low Mg(2+) environments and resistance to host defense antimicrobial peptides. Essential for intramacrophage survival of S.typhimurium. In low periplasmic Mg(2+), PhoQ functions as a membrane-associated protein kinase that undergoes autophosphorylation and subsequently transfers the phosphate to PhoP, resulting in the expression of PhoP-activated genes (PAG) and repression of PhoP-repressed genes (PRG). In high periplasmic Mg(2+), acts as a protein phosphatase that dephosphorylates phospho-PhoP, resulting in the repression of PAG and may lead to expression of some PRG. Essential for transcription of spiC inside macrophages by controlling the expression of the two-component regulatory system SsrB/SpiR (SsrA) and Pir at transcriptional and post-transcriptional levels respectively. Promotes expression of the two-component regulatory system PmrA/PmrB via activation of pmrD gene. Is required to attenuate bacterial growth within fibroblast cells and to enhance bacterial resistance to bile in intestinal cells. Negatively regulates prgH, which is required for invasion of epithelial cells. Involved in acid tolerance.^[1] ^[2] ^[3]

Publication Abstract from PubMed

Salmonella PhoQ is a histidine kinase with a periplasmic sensor domain (PD) that promotes virulence by detecting the macrophage phagosome. PhoQ activity is repressed by divalent cations and induced in environments of acidic pH, limited divalent cations, and cationic antimicrobial peptides (CAMP). Previously, it was unclear which signals are sensed by salmonellae to promote PhoQ-mediated virulence. We defined conformational changes produced in the PhoQ PD on exposure to acidic pH that indicate structural flexibility is induced in alpha-helices 4 and 5, suggesting this region contributes to pH sensing. Therefore, we engineered a disulfide bond between W104C and A128C in the PhoQ PD that restrains conformational flexibility in alpha-helices 4 and 5. PhoQ(W104C-A128C) is responsive to CAMP, but is inhibited for activation by acidic pH and divalent cation limitation. phoQ(W104C-A128C) Salmonella enterica Typhimurium is virulent in mice, indicating that acidic pH and divalent cation sensing by PhoQ are dispensable for virulence.

Acidic pH and divalent cation sensing by PhoQ are dispensable for systemic salmonellae virulence.,Hicks KG, Delbecq SP, Sancho-Vaello E, Blanc MP, Dove KK, Prost LR, Daley ME, Zeth K, Klevit RE, Miller SI Elife. 2015 May 23;4:e06792. doi: 10.7554/eLife.06792. PMID:26002083^[4]

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

References

↑ Miller SI, Kukral AM, Mekalanos JJ. A two-component regulatory system (phoP phoQ) controls Salmonella typhimurium virulence. Proc Natl Acad Sci U S A. 1989 Jul;86(13):5054-8. PMID:2544889
↑ Bearson BL, Wilson L, Foster JW. A low pH-inducible, PhoPQ-dependent acid tolerance response protects Salmonella typhimurium against inorganic acid stress. J Bacteriol. 1998 May;180(9):2409-17. PMID:9573193
↑ Sanowar S, Le Moual H. Functional reconstitution of the Salmonella typhimurium PhoQ histidine kinase sensor in proteoliposomes. Biochem J. 2005 Sep 15;390(Pt 3):769-76. PMID:15910283 doi:http://dx.doi.org/BJ20050060
↑ Hicks KG, Delbecq SP, Sancho-Vaello E, Blanc MP, Dove KK, Prost LR, Daley ME, Zeth K, Klevit RE, Miller SI. Acidic pH and divalent cation sensing by PhoQ are dispensable for systemic salmonellae virulence. Elife. 2015 May 23;4:e06792. doi: 10.7554/eLife.06792. PMID:26002083 doi:http://dx.doi.org/10.7554/eLife.06792

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/4uey"

@@ Line 1: / Line 1: @@
 ==Structure of the periplasmic domain PhoQ double mutant (W104C-A128C)==
-<StructureSection load='4uey' size='340' side='right' caption='[[4uey]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
+<StructureSection load='4uey' size='340' side='right'caption='[[4uey]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
 == Structural highlights ==
 <table><tr><td colspan='2'>[[4uey]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/"bacillus_cholerae-suis"_smith_1894 "bacillus cholerae-suis" smith 1894]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4UEY OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4UEY FirstGlance]. <br>
@@ Line 25: / Line 25: @@
 </StructureSection>
 [[Category: Bacillus cholerae-suis smith 1894]]
+[[Category: Large Structures]]
 [[Category: Hicks, K G]]
 [[Category: Miller, S I]]

4uey

From Proteopedia

Revision as of 11:12, 26 February 2020

Structure of the periplasmic domain PhoQ double mutant (W104C-A128C)

Structural highlights

Function

Publication Abstract from PubMed

See Also

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

Personal tools

Navigation

Search

Toolbox