title: Construction of isogenic gonococci with variable porin structure: effects on susceptibility to human serum and antibiotics.
abstract: Protein I (PI) is the most abundant protein on the gonococcal cell surface and besides its porin function it may have important properties contributing to pathogenicity. By allelic exchange using cloned PI genes from FA19 (PIA) and MS11 (PIB) and a selectable marker introduced closely downstream of these genes, we constructed sets of isogenic gonococcal strains that differ only in their PI gene. Analysis revealed that PI has a major effect on stable resistance to normal human serum, and a slight effect on low-level resistance to antibiotics. All PIA/B hybrids were hypersusceptible to serum, suggesting a possible explanation for why such hybrids do not occur in nature.
authors.affiliation: Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill 27599.
authors.forename: N
authors.initials: N
authors.lastname: Carbonetti
authors.forename: V
authors.initials: V
authors.lastname: Simnad
authors.forename: C
authors.initials: C
authors.lastname: Elkins
authors.forename: P F
authors.initials: PF
authors.lastname: Sparling
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D003165:Complement System Proteins / Q000276:immunology; D004269:DNA, Bacterial / Q000032:analysis; D004926:Escherichia coli / Q000235:genetics; D005798:Genes, Bacterial; D006801:Humans; D008070:Lipopolysaccharides / Q000032:analysis; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D009344:Neisseria gonorrhoeae / Q000235:genetics*; D010403:Penicillin Resistance / Q000235:genetics; D018272:Porins; D015610:Serum Bactericidal Test; D013753:Tetracycline Resistance; D014169:Transformation, Bacterial
chemical_list: D001425:Bacterial Outer Membrane Proteins; D004269:DNA, Bacterial; D008070:Lipopolysaccharides; D018272:Porins; D003165:Complement System Proteins