Arac/XylS family of transcriptional regulators.

Gallegos, Marı́a-Trinidad; Schleif, Robert; Bairoch, A; Hofmann, K; Ramos, Juan L.

doi:10.1128/.61.4.393-410.1997

Cited by 671 publications

(491 citation statements)

References 134 publications

Supporting

Mentioning

476

Contrasting

Unclassified

Order By: Relevance

“…VirF and Rns make attractive subjects for study because, in addition to their common sensitivity to temperature, they share a high level of amino acid sequence identity. This identity occurs throughout the length of the proteins [6,7], in contrast to the general situation in the AraC family where relatedness is con¢ned to the carboxy-terminus of the molecules [1]. Both proteins act as activators of transcription at promoters that are subject to negative regulation by the nucleoid-associated protein H-NS [4,8].…”

Section: Introductionmentioning

confidence: 96%

See 1 more Smart Citation

Two highly related regulatory proteins, Shigella flexneri VirF and enterotoxigenic Escherichia coli Rns, have common and distinct regulatory properties

Porter¹

1998

FEMS Microbiology Letters

View full text Add to dashboard Cite

The Rns protein of enterotoxigenic Escherichia coli (ETEC) and the VirF protein of Shigella flexneri are members of the AraC family of transcription regulators. Rns is required for positive activation of the CS1 fimbrial genes, while VirF is a positive regulator of an invasion gene regulon. The amino acid sequences of the proteins are 36% identical, and both proteins activate transcription in response to increases in temperature. Here, we show that Rns is capable of complementing fully a null mutation in the S. flexneri virF gene. However, the VirF protein cannot replace Rns as an activator of CS1 gene expression in ETEC. This failure is not due to the absence from ETEC of a co-factor required by VirF since it also occurs when the CS1 system is moved into an S. flexneri genetic background. Nor is it a function of growth medium composition or a failure in virF gene expression. Instead, these findings point to important differences in the mechanisms by which these related transcription factors regulate gene expression in Gram-negative pathogens. z 1998 Federation of European Microbiological Societies. Published by Elsevier Science B.V.

show abstract

Section: Introductionmentioning

confidence: 96%

“…Members of the AraC-like family of bacterial transcription factors share a high degree of amino acid sequence similarity and identity in their carboxy-terminal domains [1]. The family may be divided into two groups, one in£uencing transcription in response to a chemical signal, and another group that responds to a physical signal.…”

Section: Introductionmentioning

confidence: 99%

Two highly related regulatory proteins, Shigella flexneri VirF and enterotoxigenic Escherichia coli Rns, have common and distinct regulatory properties

Porter¹

1998

FEMS Microbiology Letters

View full text Add to dashboard Cite

show abstract

“…Members of this family present a characteristic modular structure. The conserved C-terminal domain includes two potential tetra-helical HTH DNA-binding motifs while the N-terminal domain is not well conserved and is involved in effector recognition and dimerization (Gallegos et al, 1997). The pWW0-encoded XylS regulator mediates transcriptional activation of the Pm promoter driving the expression of the meta pathway in response to 3MBz and Bz as inducers.…”

Section: Introductionmentioning

confidence: 99%

The differential response of the Pben promoter of Pseudomonas putida mt‐2 to BenR and XylS prevents metabolic conflicts in m‐xylene biodegradation

Pérez‐Pantoja

Kim

Silva‐Rocha

2014

Environmental Microbiology

View full text Add to dashboard Cite

Pseudomonas putida mt-2 encompasses two alternative and potentially conflicting routes for benzoate metabolism, one meta pathway encoded by xyl genes of the pWW0 plasmid and mastered by the Pm promoter and XylS, and one chromosomally encoded ortho pathway initiated by Pben and the BenR protein. Any cross-activation of Pben promoter by XylS ought to cause a metabolic conflict during the degradation of m-xylene because 3-methylbenzoate (3MBz) generated as an intermediate can be channelled through the ortho pathway and produce toxic dead-end metabolites. The activation of Pben by XylS was revisited using both reporter technology and tiling arrays targeted to the sequences of interest around messenger RNA initiation of both Pben and Pm promoters. Analysis of supersensitive luxCDABE fusions, inspection of xylX versus benA transcripts and growth tests of benR mutants indicated that the natural expression ranges of XylS under various conditions are insufficient to cause a significant cross-regulation of Pben whether cells face endogenous or exogenous 3MBz. This seems to stem from the nature of the operators for binding either transcriptional factor, which in the case of the Pben promoter of P. putida mt-2 appear to have evolved for avoiding a strong interaction with XylS.

show abstract

“…The first gene of the Longus region (lngR) encodes a predicted 24-kDa protein with significant similarity to positive regulators of pili biogenesis such as PefB of Salmonella enterica serovar Typhimurium, FaeB of K88 of ETEC, Afa of uropathogenic E. coli and PapB of the Pap fimbriae (Huisman et al, 1994;Holden et al, 2001;Madhavan and Sakellaris, 2015). The lngS gene encodes a predicted protein of 269 amino acids, which is homologous to a number of bacterial AraC transcriptional activators including PerA (BFP), CfaD (CFA/I), Rns (CS1 and CS2), CofS (CFA/III) and ToxT (TCP) (Gallegos et al, 1997;Yang et al, 2011). Transcriptional regulators of the AraC family comprising at least 830 members found in Gramnegative bacterial pathogens and typically coordinate the expression of multiple virulence factors including those with roles in adherence and colonization (Gallegos et al, 1997;Egan, 2002).…”

Section: Expression Of Longus In Etec 1767mentioning

confidence: 99%

“…The lngS gene encodes a predicted protein of 269 amino acids, which is homologous to a number of bacterial AraC transcriptional activators including PerA (BFP), CfaD (CFA/I), Rns (CS1 and CS2), CofS (CFA/III) and ToxT (TCP) (Gallegos et al, 1997;Yang et al, 2011). Transcriptional regulators of the AraC family comprising at least 830 members found in Gramnegative bacterial pathogens and typically coordinate the expression of multiple virulence factors including those with roles in adherence and colonization (Gallegos et al, 1997;Egan, 2002). Presumably, both LngR and LngS individually regulate the expression of lngA (Fig.…”

Section: Expression Of Longus In Etec 1767mentioning

confidence: 99%

The expression of Longus type 4 pilus of enterotoxigenic Escherichia coli is regulated by LngR and LngS and by H‐NS, CpxR and CRP global regulators

Cruz

Ruiz-Tagle

Ares

et al. 2017

Environmental Microbiology

View full text Add to dashboard Cite

Enterotoxigenic Escherichia coli produces a long type 4 pilus called Longus. The regulatory elements and the environmental signals controlling the expression of Longus-encoding genes are unknown. We identified two genes lngR and lngS in the Longus operon, whose predicted products share homology with transcriptional regulators. Isogenic lngR and lngS mutants were considerably affected in transcription of lngA pilin gene. The expression of lngA, lngR and lngS genes was optimally expressed at 37°C at pH 7.5. The presence of glucose and sodium chloride had a positive effect on Longus expression. The presence of divalent ions, particularly calcium, appears to be an important stimulus for Longus production. In addition, we studied H-NS, CpxR and CRP global regulators, on Longus expression. The response regulator CpxR appears to function as a positive regulator of lng genes as the cpxR mutant showed reduced levels of lngRSA expression. In contrast, H-NS and CRP function as negative regulators since expression of lngA was up-regulated in isogenic hns and crp mutants. H-NS and CRP were required for salt- and glucose-mediated regulation of Longus. Our data suggest the existence of a complex regulatory network controlling Longus expression, involving both local and global regulators in response to different environmental signals.

show abstract

Arac/XylS family of transcriptional regulators.

Cited by 671 publications

References 134 publications

Two highly related regulatory proteins, Shigella flexneri VirF and enterotoxigenic Escherichia coli Rns, have common and distinct regulatory properties

Two highly related regulatory proteins, Shigella flexneri VirF and enterotoxigenic Escherichia coli Rns, have common and distinct regulatory properties

The differential response of the Pben promoter of Pseudomonas putida mt‐2 to BenR and XylS prevents metabolic conflicts in m‐xylene biodegradation

The expression of Longus type 4 pilus of enterotoxigenic Escherichia coli is regulated by LngR and LngS and by H‐NS, CpxR and CRP global regulators

Contact Info

Product

Resources

About