Expression of outer membrane protein II by gonococci in experimental gonorrhea.

Abstract

Neisseria gonorrhoeae infects mucosae ofhumans whose urogenital epithelia are most commonly involved . The infectious aptitudes of these bacteria are likely dictated by their surface components which, except for pili, have poorly defined roles in pathogenesis. Pilus * gonococci infect the human male urethra, whereas pilus -variants do not (1, 2, Boslego, J., J. M. Koomey, and J. Swanson, unpublished results) . Pilus expression promotes adherence ofgonococci to human cells in vitro (3-6), and analogous, pilus-mediated adherence in vivo to mucosal epithelium likely accounts for correlation between pilus' phenotype of gonococci and their virulence.Expression of outer membrane protein II by gonococci markedly influences their surface properties, as deduced from the colonial opacity and intercellular adherence differences of protein II -vs. protein II' organisms (7); however, the pathogenic relevance of protein II production is not understood. Variants within a given strain synthesize several distinct protein II moieties . Expression of protein II moieties is variable for gonococci in vivo among different individuals or in separate sites of an individual (8-11) . Protein II' gonococci are isolated regularly from a male's urethra and frequently from the cervix of an infected female, depending on menstrual timing, use of oral contraceptives, etc. (8, 10). But protein II -organisms populate an infected female's fallopian tubes, regardless of which protein II phenotypes reside in her cervix (11). These observations say that protein II expression relates to gonococcal pathogenicity, but they do not tell how. Certain protein II species promote attachment o£ gonococci to tissue culture cells (5,(12)(13)(14) . Colonization of HeLa cells by gonococci is also enhanced by the diminished detachment that is displayed by organisms that express particular protein II species (15). Interactions between gonococci and peripheral blood neutrophils in vitro are also influenced by elaboration of certain protein II species (16-18).The protein II repertoire expressed by a given strain consists of several structurally related polypeptides whose common and unique portions are membrane buried and surface exposed, respectively (19)(20)(21)(22)(23)(24)(25). This repertoire is encoded by a multi-J . Sola was sponsored by the National Institutes of Health summer student program . Address correspondence to

CEACAM1 Dynamics during Neisseria gonorrhoeae Suppression of CD4+ T Lymphocyte Activation

“…Slippage of the DNA polymerase during bacterial replication causes an insertion or deletion of one or more repeated sequences, thereby causing the Opa coding sequence to fall in or out of the translational reading frame. Although a relevant animal model does not exist, neisserial infection appears to require Opa proteins because gonococci recovered after natural or experimental human infection typically express one or more Opa variants (11,12).…”

'Small' talk: Opa proteins as mediators of Neisseria–host-cell communication

“…It is important to note that Opa proteins, in contrast to neisserial pili, are not required for the initial colonisation of the host, as human volunteer challenge experiments with non-opaque strains result in successful colonisation. However, colonies reisolated from these volunteers almost invariably express Opa proteins, suggesting a strong selection pressure towards the expression of Opa proteins in vivo [5,6].…”

Recombinational reassortment among opa genes from ET-37 complex Neisseria meningitidis isolates of diverse geographical origins

“…meningitidis (Woods & Cannon, 1990;Achtman et al, 1991) and N . gonorrhoeae (James & Swanson, 1978;Swanson et a/., 1988;Jerse et al, 1994). Phase variation (reversible on-off switching) of Opa proteins results from alterations in reading frame caused by changes in the number of pentanucleotide repeats (CTCTT) in the signal-peptideencoding region of opa genes (Stern et al, 1986;Stern & Meyer, 1987;Kawula et al, 1988;Belland et al, 1989Belland et al, , 1997Murphy et al, 1989).…”