Structural highlights
Function
QSEE_ECO57 Member of the two-component regulatory system QseF/QseE involved in the regulation of virulence and metabolism in EHEC. Required for pedestal formation in host epithelial cells during infection. Autophosphorylates in response to epinephrine, sulfate or phosphate and then probably transfers its phosphate group to QseF.[1] [2] [3]
Publication Abstract from PubMed
Bacteria regulate virulence by using two-component systems (TCSs) composed of a histidine kinase (HK) and a response regulator (RR). TCSs respond to environmental signals and change gene-expression levels. The HK QseE and the RR QseF regulate the virulence of Enterobacteriaceae bacteria such as enterohemorrhagic Escherichia coli. The operon encoding QseE/QseF also contains a gene encoding an outer membrane lipoprotein, qseG. The protein product QseG interacts with QseE in the periplasmic space to control the activity of QseE and constitutes a unique QseE/F/G three-component system. However, the structural bases of their functions are unknown. Here, crystal structures of the periplasmic regions of QseE and QseG were determined with the help of AlphaFold models. The periplasmic region of QseE has a helix-bundle structure as found in some HKs. The QseG structure is composed of an N-terminal globular domain and a long C-terminal helix forming a coiled-coil-like structure that contributes to dimerization. Comparison of QseG structures obtained from several crystallization conditions shows that QseG has structural polymorphisms at the C-terminus of the coiled-coil structure, indicating that the C-terminus is flexible. The C-terminal flexibility is derived from conserved hydrophilic residues that reduce the hydrophobic interaction at the coiled-coil interface. Electrostatic surface analysis suggests that the C-terminal coiled-coil region can interact with QseE. The observed structural fluctuation of the C-terminus of QseG is probably important for interaction with QseE.
Crystal structures of QseE and QseG: elements of a three-component system from Escherichia coli.,Matsumoto K, Fukuda Y, Inoue T Acta Crystallogr F Struct Biol Commun. 2023 Nov 1;79(Pt 11):285-293. doi: , 10.1107/S2053230X23009123. Epub 2023 Oct 25. PMID:37877621[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Reading NC, Torres AG, Kendall MM, Hughes DT, Yamamoto K, Sperandio V. A novel two-component signaling system that activates transcription of an enterohemorrhagic Escherichia coli effector involved in remodeling of host actin. J Bacteriol. 2007 Mar;189(6):2468-76. PMID:17220220 doi:10.1128/JB.01848-06
- ↑ Reading NC, Rasko DA, Torres AG, Sperandio V. The two-component system QseEF and the membrane protein QseG link adrenergic and stress sensing to bacterial pathogenesis. Proc Natl Acad Sci U S A. 2009 Apr 7;106(14):5889-94. PMID:19289831 doi:10.1073/pnas.0811409106
- ↑ Reading NC, Rasko D, Torres AG, Sperandio V. A transcriptome study of the QseEF two-component system and the QseG membrane protein in enterohaemorrhagic Escherichia coli O157 : H7. Microbiology (Reading). 2010 Apr;156(Pt 4):1167-1175. PMID:20056703 doi:10.1099/mic.0.033027-0
- ↑ Matsumoto K, Fukuda Y, Inoue T. Crystal structures of QseE and QseG: elements of a three-component system from Escherichia coli. Acta Crystallogr F Struct Biol Commun. 2023 Nov 1;79(Pt 11):285-293. PMID:37877621 doi:10.1107/S2053230X23009123
