Regulation of virulence by butyrate sensing in enterohaemorrhagic Escherichia coli

Nakanishi, N; Tashiro, K; Kuhara, S; Hayashi, T; Sugimoto, N; Tobe, T

HERO ID

1457441

Reference Type

Journal Article

Year

2009

Language

English

PMID

19202100

HERO ID 1457441
In Press No
Year 2009
Title Regulation of virulence by butyrate sensing in enterohaemorrhagic Escherichia coli
Authors Nakanishi, N; Tashiro, K; Kuhara, S; Hayashi, T; Sugimoto, N; Tobe, T
Journal Microbiology (Reading, England)
Volume 155
Issue Pt 2
Page Numbers 521-530
Abstract Enterohaemorrhagic Escherichia coli (EHEC) colonizes and proliferates at the mucosal surface, inducing severe diarrhoea. Short-chain fatty acids (SCFAs) are abundant in the intestine owing to the metabolic activity of microflora, and are important for colonic health. We found that, although a high concentration of SCFAs inhibited the growth of EHEC, at low concentrations, the SCFAs markedly enhanced the expression of the virulence genes required for cell adherence and the induction of attaching and effacing (A/E) lesions. Of the SCFAs tested, butyrate markedly enhanced the expression of these virulence-associated genes, even at the low concentration of 1.25 mM, but acetate and propionate showed only a small effect at concentrations higher than 40 mM. Butyrate enhanced the promoter activity of the LEE1 operon, which encodes a global regulator of the LEE genes, Ler. This enhancement was dependent on a regulator, PchA. Butyrate sensing was completely abrogated by the deletion of lrp, the gene for the leucine-responsive regulatory protein, Lrp. Expression of a constitutively active mutant of Lrp enhanced the expression of the LEE genes in the absence of butyrate, and a response-defective Lrp derivative reduced the response to butyrate. Thus, upon entering the distal ileum, EHEC may respond to the higher butyrate level via Lrp by increasing its virulence expression, leading to efficient colonization of the target niche.
Doi 10.1099/mic.0.023499-0
Pmid 19202100
Wosid WOS:000263428900020
Is Certified Translation No
Dupe Override No
Comments Source: Web of Science WOS:000263428900020
Is Public Yes
Language Text English