Format

Send to

Choose Destination
Mol Microbiol. 2016 Dec;102(5):909-924. doi: 10.1111/mmi.13497. Epub 2016 Oct 4.

Redox pathway sensing bile salts activates virulence gene expression in Vibrio cholerae.

Author information

1
College of Animal Science & Technology, China-Australia Joint-Laboratory for Animal Health Big Data Analytics, Zhejiang Provincial Engineering Laboratory for Animal Health Inspection & Internet Technology, Zhejiang A&F University, Lin'an 311300, Zhejiang Province, China.
2
Department of Animal Science, Wenzhou Vocational College of Science and Technology, Wenzhou, Zhejiang, China.
3
New England Biolabs Inc, Ipswich, Massachusetts, USA.
4
Institute of Preventive Veterinary Medicine, Zhejiang University, Hangzhou, Zhejiang, China.

Abstract

Vibrio cholerae, the causative agent of the severe diarrheal disease cholera, has evolved signal transduction systems to control co-ordinately the expression of virulence determinants. It was previously shown that the presence of the bile salts glycocholate and taurocholate in the small intestine causes dimerization of the transmembrane transcription factor TcpP by inducing intermolecular disulphide bonds in the TcpP periplasmic domain. In this study, they further investigated the mechanism of how taurocholate affects V. cholerae virulence determinants. In vitro assay of TcpP oxidation by VcDsbA showed that VcDsbA induced TcpP dimerization in the presence of taurocholate. Taurocholate bound to VcDsbA with a KD of 40 ± 2.5 μM, and also bound other Dsb proteins, including EcDsbA, EcDsbC and VcDsbC. Taurocholate inhibited VcDsbA reductase activity without affecting VcDsbA secondary structure or thermostability. VcDsbA and its substrates were more extensively reduced in the presence of taurocholate, as compared with their redox state in the absence of taurocholate. The data presented here not only provide new insights into the mechanism by which bile salts induce V. cholerae virulence but also suggest a means by which to develop inhibitors against DsbA.

PMID:
27610607
DOI:
10.1111/mmi.13497
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center