title: The ompS gene of Vibrio cholerae encodes a growth-phase-dependent maltoporin.
abstract: The outer membrane of Vibrio cholerae contains a maltose-inducible major protein, OmpS (43 kDa), that is common to different isolates. Nucleotide sequence analysis of the corresponding structural gene, ompS, revealed an open reading frame encoding a 412-amino-acid polypeptide. The amino acid sequence of OmpS is similar to that of LamB, the Escherichia coli maltoporin, and to ScrY or Klebsiella pneumoniae, although the antigenic determinants of these proteins are different. The cloned ompS gene complemented an ompS mutation of V. cholerae and the corresponding polypeptide could function as a maltoporin in a LamB- mutant of E. coli. The promoter region of ompS is highly homologous to the malK-lamB promoter of E. coli and the ompS gene is controlled by MalT in E. coli. This indicates that the same kind of regulatory mechanism is used to activate the ompS expression in V. cholerae and malK-lamB expression in E. coli. An ompS-lacZ transcriptional fusion was used to demonstrate a dual control in ompS expression; the ompS gene is responsive to the inducers maltose and trehalose but in their absence it is also expressed in response to growth-phase. These different modes of induction might be of importance during different stages of V. cholerae infection.
authors.affiliation: Department of Molecular Genetics, Uppsala Genetic Center, Swedish University of Agricultural Sciences.
authors.forename: H
authors.initials: H
authors.lastname: Lång
authors.forename: E T
authors.initials: ET
authors.lastname: Palva
mesh_terms: D000595:Amino Acid Sequence; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D001426:Bacterial Proteins; D001483:Base Sequence; D002455:Cell Division; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D029968:Escherichia coli Proteins; D005656:Fungal Proteins / Q000235:genetics; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D018272:Porins / Q000235:genetics; D011401:Promoter Regions, Genetic; D011991:Receptors, Virus / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D014734:Vibrio cholerae / Q000235:genetics* / Q000254:growth & development
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D017931:DNA Primers; D004269:DNA, Bacterial; D029968:Escherichia coli Proteins; D005656:Fungal Proteins; D018272:Porins; D011991:Receptors, Virus; C489789:ScrY protein, E coli; C079242:ScrY protein, bacteria; C016532:maltoporins; C072079:LAMB protein, Emericella nidulans