Transcriptional Regulation of the YghJ-pppA-yghG-gspCDEFGHIJKLM Cluster, Encoding the Type II Secretion Pathway in Enterotoxigenic Escherichia Coli
Overview
Affiliations
The gene cluster gspCDEFGHIJKLM codes for various structural components of the type II secretion pathway which is responsible for the secretion of heat-labile enterotoxin by enterotoxigenic Escherichia coli (ETEC). In this work, we used a variety of molecular approaches to elucidate the transcriptional organization of the ETEC type II secretion system and to unravel the mechanisms by which the expression of these genes is controlled. We showed that the gspCDEFGHIJKLM cluster and three other upstream genes, yghJ, pppA, and yghG, are cotranscribed and that a promoter located in the upstream region of yghJ plays a major role in the expression of this 14-gene transcriptional unit. Transcription of the yghJ promoter was repressed 168-fold upon a temperature downshift from 37 degrees C to 22 degrees C. This temperature-induced repression was mediated by the global regulatory proteins H-NS and StpA. Deletion mutagenesis showed that the promoter region encompassing positions -321 to +301 relative to the start site of transcription of yghJ was required for full repression. The yghJ promoter region is predicted to be highly curved and bound H-NS or StpA directly. The binding of H-NS or StpA blocked transcription initiation by inhibiting promoter open complex formation. Unraveling the mechanisms of regulation of type II secretion by ETEC enhances our understanding of the pathogenesis of ETEC and other pathogenic varieties of E. coli.
Molecular Characterization of Multidrug-Resistant from Fecal Samples of Wild Animals.
Sabenca C, Romero-Rivera M, Barbero-Herranz R, Sargo R, Sousa L, Silva F Vet Sci. 2024; 11(10).
PMID: 39453061 PMC: 11512376. DOI: 10.3390/vetsci11100469.
Hoyle D, Wee B, Macleod K, Chase-Topping M, Bease A, Tongue S Front Microbiol. 2023; 14:1260422.
PMID: 38029122 PMC: 10657854. DOI: 10.3389/fmicb.2023.1260422.
Membrane translocation process revealed by in situ structures of type II secretion system secretins.
Yu Z, Wu Y, Chen M, Huo T, Zheng W, Ludtke S Nat Commun. 2023; 14(1):4025.
PMID: 37419909 PMC: 10329019. DOI: 10.1038/s41467-023-39583-2.
Molecular and cellular insight into Escherichia coli SslE and its role during biofilm maturation.
Corsini P, Wang S, Rehman S, Fenn K, Sagar A, Sirovica S NPJ Biofilms Microbiomes. 2022; 8(1):9.
PMID: 35217675 PMC: 8881592. DOI: 10.1038/s41522-022-00272-5.
Human Mucosal IgA Immune Responses against Enterotoxigenic .
Riaz S, Steinsland H, Hanevik K Pathogens. 2020; 9(9).
PMID: 32872549 PMC: 7558491. DOI: 10.3390/pathogens9090714.