Development of a Tag/Catcher-mediated capsid virus-like particle vaccine presenting the conserved SliC antigen that blocks human lysozyme.

Virus-like particles (VLPs) are promising nanotools for the development of subunit vaccines due to high immunogenicity and safety. Herein, we explored the versatile and effective Tag/Catcher-AP205 capsid VLP (cVLP) vaccine platform to address the urgent need for the development of an effective and safe vaccine against gonorrhea. The benefits of this clinically validated cVLP platform include its ability to facilitate unidirectional, high-density display of complex/full-length antigens through an effective split-protein Tag/Catcher conjugation system.

Comprehensive Bioinformatic Assessments of the Variability of Neisseria gonorrhoeae Vaccine Candidates.

A protective vaccine is the only viable way to stop the spread of gonorrhea in the face of rising antibiotic resistance. However, the notorious phase and antigenic variation of surface proteins remains one of the challenges in vaccine development. To facilitate vaccine advancement efforts, we carried out comprehensive bioinformatic analyses of sequence variation by comparing 34 gonorrhea antigen candidates among >5,000 clinical isolates deposited in the PubMLST database.

A novel gonorrhea vaccine composed of MetQ lipoprotein formulated with CpG shortens experimental murine infection.

Bacterial surface lipoproteins are emerging as attractive vaccine candidates due to their biological importance and the feasibility of their large-scale production for vaccine manufacturing. The global prevalence of gonorrhea, resistance to antibiotics, and serious consequences to reproductive and neonatal health necessitate development of effective vaccines. Reverse vaccinology identified the surface-displayed L-methionine binding lipoprotein MetQ (NGO2139) and its homolog GNA1946 (NMB1946) as gonococcal and meningococcal vaccine candidates, respectively.

Neisseria gonorrhoeae MlaA influences gonococcal virulence and membrane vesicle production.

The six-component maintenance of lipid asymmetry (Mla) system is responsible for retrograde transport of phospholipids, ensuring the barrier function of the Gram-negative cell envelope. Located within the outer membrane, MlaA (VacJ) acts as a channel to shuttle phospholipids from the outer leaflet. We identified Neisseria gonorrhoeae MlaA (ngo2121) during high-throughput proteomic mining for potential therapeutic targets against this medically important human pathogen.

PubMLST for Antigen Allele Mining to Inform Development of Gonorrhea Protein-Based Vaccines.

() is a human-specific pathogen and the etiological agent of gonorrhea, a sexually transmitted infection with a significant global health burden. While often asymptomatic, untreated gonorrhea can lead to pelvic inflammatory disease, ectopic pregnancy, infertility, and increased transmission/acquisition of HIV. A protective gonorrhea vaccine may be the only way to control disease transmission in the future due to the inexorable development of antibiotic resistance.

Lipid-Modified Azurin of Is Not Surface Exposed and Does Not Interact With the Nitrite Reductase AniA.

Lipid-modified cupredoxin azurin (Laz) is involved in electron transport in and proposed to act as an electron donor to the surface-displayed nitrite reductase AniA. We identified Laz in cell envelopes and naturally elaborated membrane vesicles in proteomic investigations focused on discovering new vaccine and therapeutic targets for this increasingly difficult to treat pathogen. Its surface exposure in suggested Laz could be a vaccine candidate for .

Reductive Metabolism of Xanthohumol and 8-Prenylnaringenin by the Intestinal Bacterium Eubacterium ramulus.

Scope: The intestinal microbiota transforms a wide range of available substrates, including polyphenols. Microbial catabolites of polyphenols can contribute in significant ways to the health-promoting properties of their parent polyphenols. This work aims to identify intestinal metabolites of xanthohumol (XN), a prenylated flavonoid found in hops (Humulus lupulus) and beer, as well as to identify pathways of metabolism of XN in the gut.

Quantitative Proteomics of the 2016 WHO Reference Strains Surveys Vaccine Candidates and Antimicrobial Resistance Determinants.

The sexually transmitted disease gonorrhea (causative agent: ) remains an urgent public health threat globally because of its reproductive health repercussions, high incidence, widespread antimicrobial resistance (AMR), and absence of a vaccine. To mine gonorrhea antigens and enhance our understanding of gonococcal AMR at the proteome level, we performed the first large-scale proteomic profiling of a diverse panel ( = 15) of gonococcal strains, including the 2016 World Health Organization (WHO) reference strains. These strains show all existing AMR profiles - established through phenotypic characterization and reference genome publication - and are intended for quality assurance in laboratory investigations.

Transkingdom network reveals bacterial players associated with cervical cancer gene expression program.

Cervical cancer is the fourth most common cancer in women worldwide with human papillomavirus (HPV) being the main cause the disease. Chromosomal amplifications have been identified as a source of upregulation for cervical cancer driver genes but cannot fully explain increased expression of immune genes in invasive carcinoma. Insight into additional factors that may tip the balance from immune tolerance of HPV to the elimination of the virus may lead to better diagnosis markers.

Proteomics of Vibrio cholerae.

Combining high-throughput mass spectrometry with isobaric tags for relative and absolute quantification (iTRAQ) allows for the identification and relative quantification of proteins from multiple samples. Furthermore, low-abundance proteins that are usually not detected can be enriched by using only the relevant fraction of the proteome, e.g.

SliC is a surface-displayed lipoprotein that is required for the anti-lysozyme strategy during Neisseria gonorrhoeae infection.

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).

Structural and functional insights into the role of BamD and BamE within the β-barrel assembly machinery in .

The β-barrel assembly machinery (BAM) is a conserved multicomponent protein complex responsible for the biogenesis of β-barrel outer membrane proteins (OMPs) in Gram-negative bacteria. Given its role in the production of OMPs for survival and pathogenesis, BAM represents an attractive target for the development of therapeutic interventions, including drugs and vaccines against multidrug-resistant bacteria such as The first structure of BamA, the central component of BAM, was from , the etiological agent of the sexually transmitted disease gonorrhea. To aid in pharmaceutical targeting of BAM, we expanded our studies to BamD and BamE within BAM of this clinically relevant human pathogen.

Detection of bacterial-reactive natural IgM antibodies in desert bighorn sheep populations.

Ecoimmunology is a burgeoning field of ecology which studies immune responses in wildlife by utilizing general immune assays such as the detection of natural antibody. Unlike adaptive antibodies, natural antibodies are important in innate immune responses and often recognized conserved epitopes present in pathogens. Here, we describe a procedure for measuring natural antibodies reactive to bacterial antigens that may be applicable to a variety of organisms.

Peptide Inhibitors Targeting the Neisseria gonorrhoeae Pivotal Anaerobic Respiration Factor AniA.

causes the sexually transmitted infection gonorrhea, which is highly prevalent worldwide and has a major impact on reproductive and neonatal health. The superbug status of necessitates the development of drugs with different mechanisms of action. Here, we focused on targeting the nitrite reductase AniA, which is a pivotal component of anaerobic respiration and biofilm formation.

Functional and structural studies on the Neisseria gonorrhoeae GmhA, the first enzyme in the glycero-manno-heptose biosynthesis pathways, demonstrate a critical role in lipooligosaccharide synthesis and gonococcal viability.

Sedoheptulose-7-phosphate isomerase, GmhA, is the first enzyme in the biosynthesis of nucleotide-activated-glycero-manno-heptoses and an attractive, yet underexploited, target for development of broad-spectrum antibiotics. We demonstrated that GmhA homologs in Neisseria gonorrhoeae and N. meningitidis (hereafter called GmhA and GmhA , respectively) were interchangeable proteins essential for lipooligosaccharide (LOS) synthesis, and their depletion had adverse effects on neisserial viability.

Akkermansia muciniphila mediates negative effects of IFNγ on glucose metabolism.

Cross-talk between the gut microbiota and the host immune system regulates host metabolism, and its dysregulation can cause metabolic disease. Here, we show that the gut microbe Akkermansia muciniphila can mediate negative effects of IFNγ on glucose tolerance. In IFNγ-deficient mice, A.

Proteomics-driven Antigen Discovery for Development of Vaccines Against Gonorrhea.

Expanding efforts to develop preventive gonorrhea vaccines is critical because of the dire possibility of untreatable gonococcal infections. Reverse vaccinology, which includes genome and proteome mining, has proven very successful in the discovery of vaccine candidates against many pathogenic bacteria. However, progress with this approach for a gonorrhea vaccine remains in its infancy.

Targeting an Essential GTPase Obg for the Development of Broad-Spectrum Antibiotics.

A promising new drug target for the development of novel broad-spectrum antibiotics is the highly conserved small GTPase Obg (YhbZ, CgtA), a protein essential for the survival of all bacteria including Neisseria gonorrhoeae (GC). GC is the agent of gonorrhea, a prevalent sexually transmitted disease resulting in serious consequences on reproductive and neonatal health. A preventive anti-gonorrhea vaccine does not exist, and options for effective antibiotic treatments are increasingly limited.

The Neisseria gonorrhoeae Obg protein is an essential ribosome-associated GTPase and a potential drug target.

Background: Neisseria gonorrhoeae (GC) is a Gram-negative pathogen that most commonly infects mucosal surfaces, causing sexually transmitted urethritis in men and endocervicitis in women. Serious complications associated with these infections are frequent and include pelvic inflammatory disease, ectopic pregnancy, and infertility. The incidence of gonorrhea cases remains high globally while antibiotic treatment options, the sole counter measures against gonorrhea, are declining due to the remarkable ability of GC to acquire resistance.

A metalloprotease secreted by the type II secretion system links Vibrio cholerae with collagen.

Vibrio cholerae is autochthonous to various aquatic niches and is the etiological agent of the life-threatening diarrheal disease cholera. The persistence of V. cholerae in natural habitats is a crucial factor in the epidemiology of cholera.

Isolation of Cell Envelopes and Naturally Released Membrane Vesicles of Neisseria gonorrhoeae.

Neisseria gonorrhoeae (GC) is a strict human pathogen and the agent of the sexually transmitted disease gonorrhea. Gonococcal infections have been successfully treated with antibiotics; however, GC has repeatedly developed resistance to each new antibiotic used. Currently, third-generation cephalosporins are recommended, and resistance to these antimicrobials is emerging worldwide.

Quantitative proteomic analysis of the cell envelopes and native membrane vesicles derived from gram-negative bacteria.

Proteins localized to the cell envelope and naturally released membrane vesicles (MVs) play diverse functions in physiology and pathogenesis of Gram-negative bacteria. Study of these proteome fractions is essential for better understanding the basic physiological processes, development of vaccines, and identification of potential drug targets. This unit presents gel-free quantitative proteomic methods for comprehensive proteomic profiling of the cell envelopes and MVs.

The type II secretion pathway in Vibrio cholerae is characterized by growth phase-dependent expression of exoprotein genes and is positively regulated by σE.

Vibrio cholerae, an etiological agent of cholera, circulates between aquatic reservoirs and the human gastrointestinal tract. The type II secretion (T2S) system plays a pivotal role in both stages of the lifestyle by exporting multiple proteins, including cholera toxin. Here, we studied the kinetics of expression of genes encoding the T2S system and its cargo proteins.

Quantitative proteomics of the Neisseria gonorrhoeae cell envelope and membrane vesicles for the discovery of potential therapeutic targets.

Neisseria gonorrhoeae (GC) is a human-specific pathogen, and the agent of a sexually transmitted disease, gonorrhea. There is a critical need for new approaches to study and treat GC infections because of the growing threat of multidrug-resistant isolates and the lack of a vaccine. Despite the implied role of the GC cell envelope and membrane vesicles in colonization and infection of human tissues and cell lines, comprehensive studies have not been undertaken to elucidate their constituents.

Analysis and expansion of the role of the Escherichia coli protein ProQ.

The decrease in proline transport by the proline porter ProP in a ΔproQ strain has been well documented; however, the reason for this phenotype remains undefined. Previous studies have speculated that ProQ facilitates translation of proP mRNA. Here, we demonstrate that ProQ is enriched in the polysome fractions of sucrose gradient separations of E.