Vibrio parahaemolyticus toxRS operon (VP0819-VP0820) regulates outer membrane proteins OmpU and OmpN that are important for survival in acid stress
نویسندگان
چکیده
Introduction One of the main regulators of virulence in Vibrio cholerae is the two-component regulator ToxRS. In V. cholerae, ToxR binds to the promoter and activates the toxT gene, which in turn activates the expression of a number of virulence genes, such as ctxA and tcpA (DiRita et al. 1991). Additonally, ToxR has also been shown to regulate the two outer membrane porins, OmpU and OmpT in a manner that is independent of ToxT (Miller et al. 1988). It has also been demonstrated in V. cholerae that ToxRS is necessary for the survival of the organism when faced with certain environmental stresses such as low pH and bile (Merrel et al. 1999; Provenzano et al. 2000a; Provenzano et al. 2000b). Furthermore, it has been shown that the survival defect exhibited by toxRS knockout mutants is most likely due to the lack of OmpU in the outer membrane, though an exact mechanism has yet to be elucidated (Merrel et al. 2000).
منابع مشابه
Analysis of ToxR-dependent transcription activation of ompU, the gene encoding a major envelope protein in Vibrio cholerae.
The membrane proteins ToxR and ToxS regulate a variety of genes associated with the virulence of Vibrio cholerae, the agent of human cholera. One of the ToxRS-regulated genes is the ompU gene, which encodes a porin that may also act as an adhesin. To begin to understand the mechanism of ompU transcription activation by ToxRS, we performed genetic and biochemical studies on the ompU promoter. De...
متن کاملA novel suicide vector and its use in construction of insertion mutations: osmoregulation of outer membrane proteins and virulence determinants in Vibrio cholerae requires toxR.
The toxR gene of Vibrio cholerae encodes a transmembrane, DNA-binding protein that activates transcription of the cholera toxin operon and a gene (tcpA) for the major subunit of a pilus colonization factor. We constructed site-directed insertion mutations in the toxR gene by a novel method employing the chromosomal integration of a mobilizable suicide plasmid containing a portion of the toxR co...
متن کاملImmune response in Lutjanus erythropterus induced by the major outer membrane protein (OmpU) of Vibrio alginolyticus.
The outer membrane proteins (OMPs) of the marine aquatic animal pathogen Vibrio alginolyticus play an important role in the virulence of the bacterium and are potential candidates for vaccine development. In this study, the major 35.6 kDa OMP of V. alginolyticus was isolated by gel excision from the crude OMP fraction from V. alginolyticus. The sequence of the first 27 amino acid residues from ...
متن کاملCrystal structure of the outer membrane protein OmpU from Vibrio cholerae at 2.2 Å resolution
Vibrio cholerae causes a severe disease that kills thousands of people annually. The outer membrane protein OmpU is the most abundant outer membrane protein in V. cholerae, and has been identified as an important virulence factor that is involved in host-cell interaction and recognition, as well as being critical for the survival of the pathogenic V. cholerae in the host body and in harsh envir...
متن کاملThe virulence regulatory protein ToxR mediates enhanced bile resistance in Vibrio cholerae and other pathogenic Vibrio species.
The transmembrane regulatory protein ToxR is required for expression of virulence factors in the human diarrheal pathogen Vibrio cholerae, including cholera toxin (CT) and the toxin coregulated pilus (TCP). ToxR is necessary for transcription of the gene encoding a second regulatory protein, ToxT, which is the direct transcriptional activator of CT and TCP genes. However, ToxR, independent of T...
متن کامل