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

Abstract

We present the first large-scale quantitative MS-based profiling of cell envelopes and cytoplasmic proteins derived from a diverse panel of WHO gonococcal reference strains possessing all existing AMR profiles and intended for quality assurance in laboratory investigations. We describe nine novel gonorrhea vaccine candidates and six potential global proteomic AMR markers. A reference proteomics databank for gonococcal vaccine and AMR research endeavors is provided, which enables microbiological, clinical, or epidemiological projects and enhances the utility of the WHO reference strains. Graphical Abstract Highlights• Quantitative proteomes of the 2016 WHO Neisseria gonorrhoeae reference strains.• Novel gonorrhea vaccine candidates and potential global proteomic AMR markers.• First large-scale proteomic profiling of gonorrhea vaccine candidates and AMR.• A reference proteomics databank for gonococcal vaccine and AMR research endeavors.

Comparative Proteomics of Extended-Spectrum Cephalosporin-Resistant Neisseria gonorrhoeae Isolates Demonstrates Altered Protein Synthesis, Metabolism, Substance Transport, and Membrane Permeability

“…In our study, we observed that the expression of MtrR in the ESC-resistant isolates were downregulated, suggesting decreased repression of the MtrCDE efflux pump, thereby increasing cellular expulsion of antimicrobials. This is consistent with findings that decreased expression of MtrR is associated with increased CRO MICs (El-Rami et al, 2019). Expression of a predicted membrane protein (A0A1D3E8W0) was upregulated in the three ESC-resistant isolates.…”

“…Expression of a predicted membrane protein (A0A1D3E8W0) was upregulated in the three ESC-resistant isolates. However, the expression of this protein was downregulated in the WHO-L N. gonorrhoeae strain that was ESC-resistant (El-Rami et al, 2019). In El-Rami's study, proteomic analysis was performed on proteins of subcellular fractionation, whereas in the present study, proteomic analysis was conducted on proteins from the whole cell extracts.…”

“…Normalized abundance was calculated from the raw abundance divided by the normalization factor. Differentially expressed proteins were filtered if their fold change (FC) was over 1.5 or below −1.5 as compared to ATCC49226 and contained at least 2 unique peptides (P < 0.01) (Baarda et al, 2019;El-Rami et al, 2019).…”

“…Neisseria gonorrhoeae cells were cultivated on GC agar plates and incubated for 20 h in 5% CO 2 at 37 • C (Wu et al, 2010;Nabu et al, 2017;El-Rami et al, 2019). Subsequently, cells were harvested in 0.1 M phosphate-buffered solution (PBS), pH 7.4.…”

“…In a comparative proteomics study, over 13 proteins were differentially expressed in response to ESC stimulation (Nabu et al, 2017). A proteomics study of the 2016 WHO N. gonorrhoeae reference strains with various profiles of AMR phenotypes and the N. gonorrhoeae strain FA6140 provided a reference proteomics databank for N. gonorrhoeae AMR research endeavors (El-Rami et al, 2019). Previous reports also revealed that expression of an outer membrane protein NGO1985 in N. gonorrhoeae was upregulated in response to antimicrobial stimulation (Zielke et al, 2014).…”