Lipooligosaccharide (LOS) has been implicated in the adhesion and invasion of host epithelial cells. We examined the adhesive and invasive abilities of isogenic gonococcal opacity-associated outer membrane protein-negative, pilus-positive (Opa-Pil+) Neisseria gonorrhoeae strains expressing genetically defined LOS. Strain F62 (Opa-Pil+), expressing the lacto-N-neotetraose and the galNac-lacto-N-...

Protein III (PIII) is a highly conserved, antigenically stable gonococcal outer membrane protein that is closely associated with the major outer membrane protein, protein I (PI). We have previously reported the cloning of the PIII gene. This gene was inserted into the Eco RI site of the runaway plasmid pMOB45. The beta-lactamase (beta la) Bam HI restriction fragment from the gonococcal plasmid ...

Lipooligosaccharide (LOS) heptose (Hep) glycan substitutions influence gonococcal serum resistance. Several gonococcal strains bind the classical complement pathway inhibitor, C4b-binding protein (C4BP), via their porin (Por) molecule to escape complement-dependent killing by normal human serum (NHS). We show that the proximal glucose (Glc) on HepI is required for C4BP binding to Por1B-bearing ...

The fbpABC locus of Neisseria gonorrhoeae has been proposed to encode a periplasmic protein-dependent iron transport system. Although the function of the gonococcal FbpA protein has been well characterized and its role as a periplasmic binding protein is well defined, little is known about the function of the FbpB and FbpC proteins. To define the function of the gonococcal FbpC protein, an N. g...

A locus involved in the biosynthesis of gonococcal lipooligosaccharide (LOS) has been cloned from gonococcal strain F62. The locus contains five open reading frames. The first and second reading frames are homologous, but not identical, to the fourth and fifth reading frames, respectively. Interposed is an additional reading frame which has distant homology to the Escherichia coli rfaI and rfaI...

Cotransformation remains the only tool for establishing linkage in Neisseria gonorrhoeae. Because of the difficulty of inducing auxotrophic markers via mutagenesis in this species, most previous studies have utilized antibiotic resistance and naturally occurring (auxotypic) auxotrophic markers. We have succeeded in isolating auxotrophic and temperature-sensitive mutants. The temperature-sensiti...

This report describes the cloning and sequencing of the major iron-regulated protein (termed Fbp) of Neisseria gonorrhoeae strain F62. Attempts to identify recombinants expressing the Fbp using specific antibody proved unsuccessful. Therefore, an alternative cloning strategy using oligonucleotide probes derived from NH2-terminal and tryptic fragments of this protein was used to identify short f...

The interaction of human and mouse phagocytic leukocytes with representative virulent (F62-T1) and avirulent (F62-T4, RD-5) strains of Neisseria gonorrhoeae was studied in vitro. Leukocyte monolayers were incubated with gonococci for 30 min at 37 C, washed repeatedly, reincubated with fresh medium, and sampled for viable bacteria at intervals. After the initial incubation period and washing, hu...