scholarly journals Structure of the RecombinantNeisseria gonorrhoeaeAdhesin Complex Protein (rNg-ACP) and Generation of Murine Antibodies with Bactericidal Activity against Gonococci

mSphere ◽  
2018 ◽  
Vol 3 (5) ◽  
Author(s):  
Hannia Liliana Almonacid-Mendoza ◽  
María Victoria Humbert ◽  
Aiste Dijokaite ◽  
David W. Cleary ◽  
Yiwen Soo ◽  
...  
Keyword(s):  
Neisseria Gonorrhoeae ◽  
Sexually Transmitted Disease ◽  
Transmitted Disease ◽  
Causative Organism ◽  
Human Lysozyme ◽  
Content Type ◽  
Sexually Transmitted ◽  
Innate Defense ◽  
Complex Protein

ABSTRACTNeisseria gonorrhoeae(gonococcus [Ng]) is the causative organism of the sexually transmitted disease gonorrhoea, and no effective vaccine exists currently. In this study, the structure, biological properties, and vaccine potential of the Ng-adhesin complex protein (Ng-ACP) are presented. The crystal structure of recombinant Ng-ACP (rNg-ACP) protein was solved at 1.65 Å. Diversity and conservation of Ng-ACP were examined in differentNeisseriaspecies and gonococcal isolates (https://pubmlst.org/neisseria/database)in silico, and protein expression among 50 gonococcal strains in the Centers for Disease Control and Prevention/Food and Drug Administration (CDCP/FDA) AR Isolate Bank was examined by Western blotting. Murine antisera were raised to allele 10 (strain P9-17)-encoded rNg-ACP protein with different adjuvants and examined by enzyme-linked immunosorbent assay (ELISA), Western blotting, and a human serum bactericidal assay. Rabbit antiserum to rNg-ACP was tested for its ability to prevent Ng-ACP from inhibiting human lysozyme activityin vitro.Ng-ACP is structurally homologous toNeisseria meningitidisACP and MliC/PliC lysozyme inhibitors. Gonococci expressed predominantly allele 10- and allele 6-encoded Ng-ACP (81% and 15% of isolates, respectively). Murine antisera were bactericidal (titers of 64 to 512,P < 0.05) for the homologous P9-17 strain and heterologous (allele 6) FA1090 strain. Rabbit anti-rNg-ACP serum prevented Ng-ACP from inhibiting human lysozyme with ∼100% efficiency. Ng-ACP protein was expressed by all 50 gonococcal isolates examined with minor differences in the relative levels of expression. rNg-ACP is a potential vaccine candidate that induces antibodies that (i) are bactericidal and (ii) prevent the gonococcus from inhibiting the lytic activity of an innate defense molecule.IMPORTANCENeisseria gonorrhoeae(gonococcus [Ng]) is the causative organism of the sexually transmitted disease gonorrhoea, and the organism is listed by the World Health Organization as a high-priority pathogen for research and development of new control measures, including vaccines. In this study, we demonstrated that theN. gonorrhoeaeadhesin complex protein (Ng-ACP) was conserved and expressed by 50 gonococcal strains and that recombinant proteins induced antibodies in mice that killed the bacteriain vitro. We determined the structure of Ng-ACP by X-ray crystallography and investigated structural conservation withNeisseria meningitidisACP and MliC/PliC proteins from other bacteria which act as inhibitors of the human innate defense molecule lysozyme. These findings are important and suggest that Ng-ACP could provide a potential dual target for tackling gonococcal infections.

scholarly journals Semen-Derived Enhancer of Viral Infection (SEVI) Binds Bacteria, Enhances Bacterial Phagocytosis by Macrophages, and Can Protect against Vaginal Infection by a Sexually Transmitted Bacterial Pathogen

2013 ◽  
Vol 57 (6) ◽  
pp. 2443-2450 ◽  
Author(s):  
David Easterhoff ◽  
Fernando Ontiveros ◽  
Lauren R. Brooks ◽  
Yoel Kim ◽  
Brittany Ross ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Neisseria Gonorrhoeae ◽  
Viral Infection ◽  
Bacterial Pathogen ◽  
Prostatic Acid Phosphatase ◽  
Necrosis Factor Alpha ◽  
Content Type ◽  
Sexually Transmitted ◽  
A Charge

ABSTRACTThe semen-derived enhancer of viral infection (SEVI) is a positively charged amyloid fibril that is derived from a self-assembling proteolytic cleavage fragment of prostatic acid phosphatase (PAP248-286). SEVI efficiently facilitates HIV-1 infectionin vitro, but its normal physiologic function remains unknown. In light of the fact that other amyloidogenic peptides have been shown to possess direct antibacterial activity, we investigated whether SEVI could inhibit bacterial growth. Neither SEVI fibrils nor the unassembled PAP248-286peptide had significant direct antibacterial activityin vitro. However, SEVI fibrils bound to both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coliandNeisseria gonorrhoeae) bacteria, in a charge-dependent fashion. Furthermore, SEVI fibrils but not the monomeric PAP248-286peptide promoted bacterial aggregation and enhanced the phagocytosis of bacteria by primary human macrophages. SEVI also enhanced binding of bacteria to macrophages and the subsequent release of bacterially induced proinflammatory cytokines (tumor necrosis factor alpha [TNF-α], interleukin-6 [IL-6], and IL-1β). Finally, SEVI fibrils inhibited murine vaginal colonization withNeisseria gonorrhoeae. These findings demonstrate that SEVI has indirect antimicrobial activity and that this activity is dependent on both the cationic charge and the fibrillar nature of SEVI.

scholarly journals Novel Insights into the Molecular Events Linking to Cell Death Induced by Tetracycline in the Amitochondriate Protozoan Trichomonas vaginalis

2015 ◽  
Vol 59 (11) ◽  
pp. 6891-6903 ◽  
Author(s):  
Kuo-Yang Huang ◽  
Fu-Man Ku ◽  
Wei-Hung Cheng ◽  
Chi-Ching Lee ◽  
Po-Jung Huang ◽  
...  
Keyword(s):  
Cell Death ◽  
Trichomonas Vaginalis ◽  
Transmitted Disease ◽  
Chemotherapeutic Agents ◽  
Public Health Issue ◽  
Rna Seq ◽  
Content Type ◽  
Sexually Transmitted ◽  
Molecular Events

ABSTRACTTrichomonas vaginaliscolonizes the human urogenital tract and causes trichomoniasis, the most common nonviral sexually transmitted disease. Currently, 5-nitroimidazoles are the only recommended drugs for treating trichomoniasis. However, increased resistance of the parasite to 5-nitroimidazoles has emerged as a highly problematic public health issue. Hence, it is essential to identify alternative chemotherapeutic agents against refractory trichomoniasis. Tetracycline (TET) is a broad-spectrum antibiotic with activity against several protozoan parasites, but the mode of action of TET in parasites remains poorly understood. Thein vitroeffect of TET on the growth ofT. vaginaliswas examined, and the mode of cell death was verified by various apoptosis-related assays. Next-generation sequencing-based RNA sequencing (RNA-seq) was employed to elucidate the transcriptome ofT. vaginalisin response to TET. We show that TET has a cytotoxic effect on both metronidazole (MTZ)-sensitive and -resistantT. vaginalisisolates, inducing some features resembling apoptosis. RNA-seq data reveal that TET significantly alters the transcriptome via activation of specific pathways, such as aminoacyl-tRNA synthetases and carbohydrate metabolism. Functional analyses demonstrate that TET disrupts the hydrogenosomal membrane potential and antioxidant system, which concomitantly elicits a metabolic shift toward glycolysis, suggesting that the hydrogenosomal function is impaired and triggers cell death. Collectively, we providein vitroevidence that TET is a potential alternative therapeutic choice for treating MTZ-resistantT. vaginalis. The in-depth transcriptomic signatures inT. vaginalisupon TET treatment presented here will shed light on the signaling pathways linking to cell death in amitochondriate organisms.

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