title: Effects of mutations and deletions on expression of the Enterobacter cloacae ompX gene.
abstract: The Enterobacter cloacae outer membrane protein OmpX is involved in resistance to beta-lactams, and possesses virulence characteristics. To gain more insight into the genetic elements that are important for OmpX expression, several mutations were introduced at, and immediately upstream of, the N-terminus of the OmpX coding sequence. These mutations enabled us to delete the 5' untranslated region and the signal peptide coding sequence. The former led to decreased ompX expression, indicating an unexpected and hitherto unexplained role for this region. Deletion of the signal peptide coding sequence blocked transport across the cytoplasmic membrane, indicating that translocation of OmpX across the cytoplasmic membrane is mediated by the general secretory pathway.
authors.affiliation: Department of Medical Microbiology, University Hospital, Leiden, The Netherlands.
authors.forename: G
authors.initials: G
authors.lastname: de Kort
authors.forename: P
authors.initials: P
authors.lastname: van der Bent-Klootwijk
authors.forename: R A
authors.initials: RA
authors.lastname: van Boxtel
authors.forename: J A
authors.initials: JA
authors.lastname: van de Klundert
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000096:biosynthesis* / Q000378:metabolism; D001692:Biological Transport; D002462:Cell Membrane / Q000378:metabolism; D016972:Enterobacter cloacae / Q000235:genetics*; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial / Q000235:genetics*; D006867:Hydrolases; D016296:Mutagenesis; D021382:Protein Sorting Signals / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D017384:Sequence Deletion / Q000235:genetics*
chemical_list: D001425:Bacterial Outer Membrane Proteins; D029968:Escherichia coli Proteins; D021382:Protein Sorting Signals; D012333:RNA, Messenger; C482905:OmpX protein, E coli; D006867:Hydrolases