muramidase and Gonorrhea

Topics: Adolescent; Adult; Anti-Bacterial Agents; Cervix Mucus; Enzyme Activation; Female; Gonorrhea; Humans; Immunity, Innate; Muramidase

Mouthwash is a commonly used product and has been proposed as an alternative intervention to prevent gonorrhea transmission. However, the long-term effects of mouthwash on the oral microbiota are largely unknown. We investigated the impact of 12 weeks of daily mouthwash use on the oropharyngeal microbiota in a subset of men who have sex with men who participated in a randomized trial comparing the efficacy of two alcohol-free mouthwashes for the prevention of gonorrhea. We characterized the oropharyngeal microbiota using 16S rRNA gene sequencing of tonsillar fossae samples collected before and after 12 weeks of daily use of Listerine mouthwash or Biotène dry mouth oral rinse. Permutational multivariate analysis of variance (PERMANOVA) was used to assess differences in oropharyngeal microbiota composition following mouthwash use. Differential abundance testing was performed using ALDEx2, with false-discovery rate correction. A total of 306 samples from 153 men were analyzed (Listerine,

Topics: Adult; Double-Blind Method; Drug Combinations; Glucose Oxidase; Gonorrhea; Homosexuality, Male; Humans; Lactoperoxidase; Male; Microbiota; Mouthwashes; Muramidase; Oropharynx; RNA, Ribosomal, 16S; Salicylates; Sexual and Gender Minorities; Terpenes; Young Adult

To address the increasing incidence of gonorrhoea and antimicrobial resistance, we compared the efficacy of Listerine and Biotène mouthwashes for preventing gonorrhoea among men who have sex with men (MSM).. The OMEGA trial was a multicentre, parallel-group, double-blind randomised controlled trial among MSM, done at three urban sexual health clinics and one general practice clinic in Australia. Men were eligible if they were diagnosed with oropharyngeal gonorrhoea by nucleic acid amplification test (NAAT) in the previous 30 days or were aged 16-24 years. They were randomly assigned to receive Listerine (intervention) or Biotène (control) via a computer-generated sequence (1:1 ratio, block size of four). Participants, clinicians, data collectors, data analysts, and outcome adjudicators were masked to the interventions after assignment. Participants were instructed to rinse and gargle with 20 mL of mouthwash for 60 s at least once daily for 12 weeks. Oropharyngeal swabs were collected by research nurses every 6 weeks, and participants provided saliva samples every 3 weeks, to be tested for Neisseria gonorrhoeae with NAAT and quantitative PCR. The primary outcome was proportion of MSM diagnosed with oropharyngeal N gonorrhoeae infection at any point over the 12-week period, defined as a positive result for either oropharyngeal swabs or saliva samples by NAAT, and the cumulative incidence of oropharyngeal gonorrhoea at the week 12 visit. A modified intention-to-treat analysis for the primary outcome was done that included men who provided at least one follow-up specimen over the 12-week study period. The trial was registered on the Australian and New Zealand Clinical Trials Registry (ACTRN12616000247471).. Between March 30, 2016, and Oct 26, 2018, 786 MSM were screened and 256 were excluded. 264 MSM were randomly assigned to the Biotène group and 266 to the Listerine group. The analysis population included 227 (86%) men in the Biotène group and 219 (82%) in the Listerine group. Oropharyngeal gonorrhoea was detected in ten (4%) of 227 of MSM in the Biotène group and in 15 (7%) of 219 in the Listerine group (adjusted risk difference 2·5%, 95% CI -1·8 to 6·8). The cumulative incidence of oropharyngeal gonorrhoea at the week 12 visit did not differ between the two mouthwash groups (adjusted risk difference 3·1%, 95% CI -1·4 to 7·7).. Listerine did not reduce the incidence of oropharyngeal gonorrhoea compared with Biotène. However, previous research suggests that mouthwash might reduce the infectivity of oropharyngeal gonorrhoea; therefore, further studies of mouthwash examining its inhibitory effect on N gonorrhoeae are warranted to determine if it has a potential role for the prevention of transmission.. Australian National Health and Medical Research Council.

Topics: Adult; Anti-Infective Agents, Local; Australia; Double-Blind Method; Drug Combinations; Glucose Oxidase; Gonorrhea; Homosexuality, Male; Humans; Lactoperoxidase; Male; Mouthwashes; Multicenter Studies as Topic; Muramidase; Neisseria gonorrhoeae; New Zealand; Respiratory Tract Infections; Salicylates; Sexual and Gender Minorities; Surveys and Questionnaires; Terpenes; Young Adult

The Gram-negative pathogen

Topics: Amino Acid Motifs; Bacterial Proteins; Enzyme Inhibitors; Gonorrhea; Host-Pathogen Interactions; Humans; Lipoproteins; Muramidase; Neisseria gonorrhoeae; Periplasm; Protein Transport

The bacterial pathogen Neisseria gonorrhoeae (Gc) infects mucosal sites rich in antimicrobial proteins, including the bacterial cell wall-degrading enzyme lysozyme. Certain Gram-negative bacteria produce protein inhibitors that bind to and inhibit lysozyme. Here, we identify Ng_1063 as a new inhibitor of lysozyme in Gc, and we define its functions in light of a second, recently identified lysozyme inhibitor, Ng_1981. In silico analyses indicated that Ng_1063 bears sequence and structural homology to MliC-type inhibitors of lysozyme. Recombinant Ng_1063 inhibited lysozyme-mediated killing of a susceptible mutant of Gc and the lysozyme-sensitive bacterium Micrococcus luteus. This inhibitory activity was dependent on serine 83 and lysine 103 of Ng_1063, which are predicted to interact with lysozyme's active site residues. Lysozyme co-immunoprecipitated with Ng_1063 and Ng_1981 from intact Gc. Ng_1063 and Ng_1981 protein levels were also increased in Gc exposed to lysozyme. Gc lacking both ng1063 and ng1981 was significantly more sensitive to killing by lysozyme than wild-type or single mutant bacteria. When exposed to human tears or saliva, in which lysozyme is abundant, survival of Δ1981Δ1063 Gc was significantly reduced compared to wild-type, and survival was restored upon addition of recombinant Ng_1981. Δ1981Δ1063 mutant Gc survival was additionally reduced in the presence of human neutrophils, which produce lysozyme. We found that while Ng_1063 was exposed on the surface of Gc, Ng_1981 was both in an intracellular pool and extracellularly released from the bacteria, suggesting that Gc employs these two proteins at multiple spatial barriers to fully neutralize lysozyme activity. Together, these findings identify Ng_1063 and Ng_1981 as critical components for Gc defense against lysozyme. These proteins may be attractive targets for antimicrobial therapy aimed to render Gc susceptible to host defenses and/or for vaccine development, both of which are urgently needed against drug-resistant gonorrhea.

Topics: Bacterial Proteins; Gonorrhea; Host-Pathogen Interactions; Humans; Muramidase; Neisseria gonorrhoeae

Lysozymes are nearly omnipresent as the first line of immune defense against microbes in animals. They exert bactericidal action through antimicrobial peptide activity and peptidoglycan hydrolysis. Gram-negative bacteria developed several weapons to battle lysozymes, including inhibitors of c-type lysozymes in the MliC/PliC family and the Neisseria adhesin complex protein (ACP). Until the recent discovery of ACP, no proteinaceous lysozyme inhibitors were reported for the genus Neisseria, including the important human pathogen N. gonorrhoeae. Here, we describe a previously unrecognized gonococcal virulence mechanism involving a protein encoded by the open reading frame ngo1063 that acts to counteract c-type Iysozyme and provides a competitive advantage in the murine model of gonorrhea. We named this protein SliC as a surface-exposed lysozyme inhibitor of c-type lysozyme. SliC displays low overall primary sequence similarity to the MliC/PliC inhibitors, but we demonstrate that it has a parallel inhibitory mechanism. Our studies provide the first evidence that bacterial proteinaceous lysozyme inhibitors protect against host lysozyme during infection based on lack of attenuation of the ΔsliC mutant in lysozyme knock-out mice, and that the conserved residues involved in lysozyme inhibition, S83 and K103, are functionally indispensable during infection in wild type mice. Recombinant SliC completely abrogated the lytic activity of human and chicken c-type lysozymes, showing a preference towards human lysozyme with an IC50 of 1.85 μM and calculated KD value of 9.2 ± 1.9 μM. In contrast, mutated SliC bearing S83A and K103A substitutions failed to protect fluorescein-labeled cell-wall from lysozyme-mediated hydrolysis. Further, we present data revealing that SliC is a surface-displayed lipoprotein released in membrane vesicles that is expressed throughout all phases of growth, in conditions relevant to different niches of the human host, and during experimental infection of the murine genital tract. SliC is also highly conserved and expressed by diverse gonococcal isolates as well as N. meningitidis, N. lactamica, and N. weaveri. This study is the first to highlight the importance of an anti-lysozyme strategy to escape the innate immune response during N. gonorrhoeae infection.

Topics: Animals; Bacterial Proteins; Chickens; Gonorrhea; Humans; Mice; Muramidase; Neisseria gonorrhoeae; Virulence; Virulence Factors

Endocervical biopsies taken from 74 female patients with gonorrhea and 18 healthy women were investigated by means of fluorescence with regard to the evidence of IgA, IgG, IgM, C3, C4, fibrinogen, lysozyme, and N. gonorrhoeae. Whereas C3, C4, fibrinogen, lysozyme, and N. gonorrhoeae were especially observed in the early stages of the disease, the amount of plasma cells producing IgA and IgG were found increased in the advanced stages of gonorrhea.

Topics: Adult; Antibody Formation; Cervix Uteri; Complement C3; Complement C4; Female; Fibrinogen; Fluorescent Antibody Technique; Gonorrhea; Humans; Immunoglobulins; Muramidase; Neisseria gonorrhoeae; Plasma Cells; Uterine Cervicitis

The authors analyze the immunity-correcting effect of antibiotic and enzyme therapy in 32 patients with gonorrheal orchidoepididymitis and 31 with gonorrhea relapses and compare it to the results of routine therapy in 60 patients with chronic and complicated gonorrhea. They come to a conclusion that combined administration of proteolytic enzymes and antibiotics more effectively corrects a number of disordered immunity nonspecific defense parameters (blood serum levels of circulating immune complexes and lysozyme).

Topics: Anti-Bacterial Agents; Chronic Disease; Drug Evaluation; Drug Therapy, Combination; Epididymitis; Gonorrhea; Humans; Male; Muramidase; Orchitis; Peptide Hydrolases; Recurrence

Topics: Gonorrhea; Humans; In Vitro Techniques; Muramidase; Neisseria gonorrhoeae; Penicillin Resistance; Penicillins; Peptide Hydrolases

Topics: Adolescent; Adult; Blood Bactericidal Activity; Female; Gonorrhea; Humans; Immunity, Innate; Male; Middle Aged; Muramidase

Topics: Acid Phosphatase; Alkaline Phosphatase; Animals; Antibodies, Bacterial; Antigen-Antibody Reactions; Cell Membrane; Colchicine; Cytoplasmic Granules; Endotoxins; Gonorrhea; Guinea Pigs; Humans; Microscopy, Electron; Muramidase; Neisseria gonorrhoeae; Neutrophils; Phagocytes; Phagocytosis; Vinblastine

Topics: Adolescent; Adult; Blood Bactericidal Activity; Complement System Proteins; Female; Gonorrhea; Humans; Male; Middle Aged; Muramidase