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1.
Cell ; 181(7): 1518-1532.e14, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-32497502

RESUMO

The rise of antibiotic resistance and declining discovery of new antibiotics has created a global health crisis. Of particular concern, no new antibiotic classes have been approved for treating Gram-negative pathogens in decades. Here, we characterize a compound, SCH-79797, that kills both Gram-negative and Gram-positive bacteria through a unique dual-targeting mechanism of action (MoA) with undetectably low resistance frequencies. To characterize its MoA, we combined quantitative imaging, proteomic, genetic, metabolomic, and cell-based assays. This pipeline demonstrates that SCH-79797 has two independent cellular targets, folate metabolism and bacterial membrane integrity, and outperforms combination treatments in killing methicillin-resistant Staphylococcus aureus (MRSA) persisters. Building on the molecular core of SCH-79797, we developed a derivative, Irresistin-16, with increased potency and showed its efficacy against Neisseria gonorrhoeae in a mouse vaginal infection model. This promising antibiotic lead suggests that combining multiple MoAs onto a single chemical scaffold may be an underappreciated approach to targeting challenging bacterial pathogens.


Assuntos
Bactérias Gram-Negativas/efeitos dos fármacos , Pirróis/metabolismo , Pirróis/farmacologia , Quinazolinas/metabolismo , Quinazolinas/farmacologia , Animais , Antibacterianos/farmacologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Feminino , Ácido Fólico/metabolismo , Bactérias Gram-Positivas/efeitos dos fármacos , Células HEK293 , Humanos , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Ovariectomia , Proteômica , Pseudomonas aeruginosa/efeitos dos fármacos
2.
Clin Microbiol Rev ; 37(1): e0009423, 2024 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-38226640

RESUMO

Neisseria gonorrhoeae infection is an important public health issue, with an annual global incidence of 87 million. N. gonorrhoeae infection causes significant morbidity and can have serious long-term impacts on reproductive and neonatal health and may rarely cause life-threatening disease. Global rates of N. gonorrhoeae infection have increased over the past 20 years. Importantly, rates of antimicrobial resistance to key antimicrobials also continue to increase, with the United States Centers for Disease Control and Prevention identifying drug-resistant N. gonorrhoeae as an urgent threat to public health. This review summarizes the current evidence for N. gonorrhoeae vaccines, including historical clinical trials, key N. gonorrhoeae vaccine preclinical studies, and studies of the impact of Neisseria meningitidis vaccines on N. gonorrhoeae infection. A comprehensive survey of potential vaccine antigens, including those identified through traditional vaccine immunogenicity approaches, as well as those identified using more contemporary reverse vaccinology approaches, are also described. Finally, the potential epidemiological impacts of a N. gonorrhoeae vaccine and research priorities for further vaccine development are described.


Assuntos
Anti-Infecciosos , Gonorreia , Vacinas , Recém-Nascido , Humanos , Neisseria gonorrhoeae , Gonorreia/tratamento farmacológico , Gonorreia/epidemiologia , Gonorreia/prevenção & controle
3.
J Infect Dis ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38877763

RESUMO

While ceftriaxone remains the first-line treatment for gonorrhoea, the US CDC recommended cefixime as a second-line treatment in 2021. We tested 1176 Neisseria gonorrhoeae isolates among clients attending the Melbourne Sexual Health Centre in 2021-2022. The prevalence of cefixime resistance was 6.3% (74/1176), azithromycin resistance was 4.9% (58/1176) and ceftriaxone resistance was 0% (0/1176). Cefixime resistance was the highest among women (16.4%, 10/61), followed by men-who-have-sex-with-women (6.4%, 7/109), and men-who-have-sex-with-men (5.8%, 57/982). The prevalence of cefixime-resistant N. gonorrhoeae exceeds the threshold of the 5% resistance level recommended by the World Health Organization; and thus, cefixime treatment would have limited benefits in Australia.

4.
J Infect Dis ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38526341

RESUMO

There is an urgent need for vaccines against Neisseria gonorrhoeae (Ng), the causative agent of gonorrhea. Vaccination with an outer-membrane vesicle (OMV)-based Neisseria meningitidis (Nm) vaccine provides some protection from Ng; however, the mechanisms underlying this cross-protection are unknown. To address this need, we developed multiplexed bead-based assays for the relative quantification of human and mouse IgG and IgA against Ng antigens. The assays were evaluated for analyte independence, dilutional linearity, specificity, sensitivity, intra- and inter-assay variability, and robustness to sample storage conditions. The assay was then used to test samples from mice and humans immunized with an Nm-OMV vaccine.

5.
J Infect Dis ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819303

RESUMO

Neisseria gonorrhoeae is widespread globally. Primary prevention is unsuccessful and antimicrobial resistance threatens optimal management. There is no specific vaccine and natural infection studies show that N. gonorrhoeae can avoid and suppress immune responses. In addition to extensive variation in expression and specificity of many gonococcal surface antigens, it induces a robust inflammatory response through the Th17 pathway with a large influx of neutrophils and inflammatory cytokines but evades macrophages. The Th1- and Th2-mediated response is suppressed, resulting in low, short-lived antibody titers. Real-world evidence suggests that gonorrhea cases are reduced among recipients of N. meningitidis group B vaccines containing outer membrane vesicles (OMV). Although the first randomized trial of an OMV-containing MenB vaccine against N. gonorrhoeae infection did not show statistically significant vaccine efficacy, ongoing trials might shed further light. Several candidate vaccine antigens for a gonococcal-specific vaccine are being evaluated preclinically but only one has reached clinical trials.

6.
Proteomics ; 24(14): e2300496, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38361220

RESUMO

Protein glycosylation is increasingly recognized as a common protein modification across bacterial species. Within the Neisseria genus O-linked protein glycosylation is conserved yet closely related Neisseria species express O-oligosaccharyltransferases (PglOs) with distinct targeting activities. Within this work, we explore the targeting capacity of different PglOs using Field Asymmetric Waveform Ion Mobility Spectrometry (FAIMS) fractionation and Data-Independent Acquisition (DIA) to allow the characterization of the impact of changes in glycosylation on the proteome of Neisseria gonorrhoeae. We demonstrate FAIMS expands the known glycoproteome of wild type N. gonorrhoeae MS11 and enables differences in glycosylation to be assessed across strains expressing different pglO allelic chimeras with unique substrate targeting activities. Combining glycoproteomic insights with DIA proteomics, we demonstrate that alterations within pglO alleles have widespread impacts on the proteome of N. gonorrhoeae. Examination of peptides known to be targeted by glycosylation using DIA analysis supports alterations in glycosylation occupancy occurs independently of changes in protein levels and that the occupancy of glycosylation is generally low on most glycoproteins. This work thus expands our understanding of the N. gonorrhoeae glycoproteome and the roles that pglO allelic variation may play in governing genus-level protein glycosylation.


Assuntos
Proteínas de Bactérias , Neisseria gonorrhoeae , Proteoma , Proteômica , Neisseria gonorrhoeae/metabolismo , Neisseria gonorrhoeae/genética , Glicosilação , Proteômica/métodos , Proteoma/metabolismo , Proteoma/análise , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Espectrometria de Mobilidade Iônica/métodos , Glicoproteínas/metabolismo , Glicoproteínas/genética , Hexosiltransferases/metabolismo , Hexosiltransferases/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética
7.
Infect Immun ; 92(1): e0017923, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38014981

RESUMO

Chlamydia trachomatis and Neisseria gonorrhoeae are the most prevalent bacterial sexually transmitted infections (STIs) globally. Despite frequent co-infections in patients, few studies have investigated how mono-infections may differ from co-infections. We hypothesized that a symbiotic relationship between the pathogens could account for the high rates of clinical co-infection. During in vitro co-infection, we observed an unexpected phenotype where the C. trachomatis developmental cycle was impaired by N. gonorrhoeae. C. trachomatis is an obligate intracellular pathogen with a unique biphasic developmental cycle progressing from infectious elementary bodies (EB) to replicative reticulate bodies (RB), and back. After 12 hours of co-infection, we observed fewer EBs than in a mono-infection. Chlamydial genome copy number remained equivalent between mono- and co-infections. This is a hallmark of Chlamydial persistence. Chlamydial persistence alters inclusion morphology but varies depending on the stimulus/stress. We observed larger, but fewer, Chlamydia during co-infection. Tryptophan depletion can induce Chlamydial persistence, but tryptophan supplementation did not reverse the co-infection phenotype. Only viable and actively growing N. gonorrhoeae produced the inhibition phenotype in C. trachomatis. Piliated N. gonorrhoeae had the strongest effect on C. trachomatis, but hyperpiliated or non-piliated N. gonorrhoeae still produced the phenotype. EB development was modestly impaired when N. gonorrhoeae were grown in transwells above the infected monolayer. C. trachomatis serovar L2 was not impaired during co-infection. Chlamydial impairment could be due to cytoskeletal or osmotic stress caused by an as-yet-undefined mechanism. We conclude that N. gonorrhoeae induces a persistence-like state in C. trachomatis that is serovar dependent.


Assuntos
Infecções por Chlamydia , Coinfecção , Gonorreia , Humanos , Chlamydia trachomatis/genética , Neisseria gonorrhoeae , Infecções por Chlamydia/microbiologia , Triptofano
8.
BMC Genomics ; 25(1): 290, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38500064

RESUMO

BACKGROUND: Antimicrobial resistance (AMR) of Neisseria gonorrhoeae is a threat to public health as strains have developed resistance to antimicrobials available for the treatment of gonorrhea. Whole genome sequencing (WGS) can detect and predict antimicrobial resistance to enhance the control and prevention of gonorrhea. Data on the molecular epidemiology of N. gonorrhoeae is sparse in Zambia. This study aimed to determine the genetic diversity of N. gonorrhoeae isolated from patients attending sexually transmitted infection (STI) clinics in Lusaka, Zambia. METHODS: A cross-sectional study that sequenced 38 N. gonorrhoeae isolated from 122 patients with gonorrhea from 2019 to 2020 was conducted. The AMR profiles were determined by the E-test, and the DNA was extracted using the NucliSens easyMaG magnetic device. Whole genome sequencing was performed on the Illumina NextSeq550 platform. The Bacterial analysis pipeline (BAP) that is readily available at: https://cge.cbs.dtu.dk/services/CGEpipeline-1.1 was used for the identification of the species, assembling the genome, multi-locus sequence typing (MLST), detection of plasmids and AMR genes. Phylogeny by single nucleotide polymorphisms (SNPs) was determined with the CCphylo dataset. RESULTS: The most frequent STs with 18.4% of isolates each were ST7363, ST1921 and ST1582, followed by ST1583 (13%), novel ST17026 (7.9%), ST1588 (7.9%), ST1596 (5.3%), ST11181 (5.3%), ST11750 (2.6/%) and ST11241 (2.6%) among the 38 genotyped isolates. The blaTeM-1B and tetM (55%) was the most prevalent combination of AMR genes, followed by blaTeM-1B (18.4%), tetM (15.8%), and the combination of blaTeM-1B, ermT, and tetL was 2.6% of the isolates. The AMR phenotypes were predicted in ciprofloxacin, penicillin, tetracycline, azithromycin, and cefixime. The combination of mutations 23.7% was gryA (S91F), parC (E91G), ponA (L421) and rpsJ (V57M), followed by 18.4% in gyrA (S91F), ponA (L421P), rpsJ (V57M), and 18.4% in gyrA (D95G, S91F), ponA (L421P), and rpsJ (V57M). The combinations in gyrA (D95G, S91F) and rpsJ (V57M), and gyrA (D95G, S91F), parC (E91F), ponA (L421P) and rpsJ (V57M) were 13.2% each of the isolates. Plasmid TEM-1 (84.2%), tetM (15.8%), and gonococcal genetic island (GGI) was detected in all isolates. CONCLUSION: This study revealed remarkable heterogeneity of N. gonorrhoeae with blaTEM-1, tetM, ponA, gyrA, and parC genes associated with high resistance to penicillin, tetracycline, and ciprofloxacin demanding revision of the standard treatment guidelines and improved antimicrobial stewardship in Zambia.


Assuntos
Antibacterianos , Gonorreia , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Neisseria gonorrhoeae/genética , Gonorreia/tratamento farmacológico , Gonorreia/epidemiologia , Gonorreia/microbiologia , Tipagem de Sequências Multilocus , Zâmbia/epidemiologia , Estudos Transversais , Farmacorresistência Bacteriana/genética , Tetraciclina , Ciprofloxacina , Penicilinas , Testes de Sensibilidade Microbiana
9.
Emerg Infect Dis ; 30(7): 1493-1495, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38916864

RESUMO

To determine antimicrobial susceptibility of Neisseria gonorrhoeae, we analyzed phenotypes and genomes of 72 isolates collected in Cambodia in 2023. Of those, 9/72 (12.5%) were extensively drug resistant, a 3-fold increase from 2022. Genomic analysis confirmed expansion of newly emerging resistant clones and ongoing resistance emergence across new phylogenetic backbones.


Assuntos
Antibacterianos , Gonorreia , Testes de Sensibilidade Microbiana , Neisseria gonorrhoeae , Organização Mundial da Saúde , Neisseria gonorrhoeae/efeitos dos fármacos , Neisseria gonorrhoeae/genética , Camboja/epidemiologia , Humanos , Gonorreia/microbiologia , Gonorreia/epidemiologia , Gonorreia/tratamento farmacológico , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Filogenia , Masculino , Feminino , Adulto
10.
Emerg Infect Dis ; 30(8): 1683-1686, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39043453

RESUMO

Ceftriaxone-resistant Neisseria gonorrhoeae FC428-like strains have disseminated across the Asia-Pacific region, with a continuous rise in prevalence during 2015-2022. To mitigate the effect of these strains, we advocate for enhanced molecular diagnostics, expanded surveillance networks, and a regionally coordinated effort to combat the global spread of FC428-like strains.


Assuntos
Antibacterianos , Ceftriaxona , Farmacorresistência Bacteriana , Gonorreia , Neisseria gonorrhoeae , Neisseria gonorrhoeae/efeitos dos fármacos , Neisseria gonorrhoeae/genética , Ceftriaxona/farmacologia , Humanos , Gonorreia/microbiologia , Gonorreia/epidemiologia , Gonorreia/tratamento farmacológico , Ásia/epidemiologia , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Prevalência , História do Século XXI
11.
Emerg Infect Dis ; 30(9)2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39084693

RESUMO

Since 2022, Europe has had 4 cases of extensively drug-resistant Neisseria gonorrhoeae, sequence type 16406, that is resistant to ceftriaxone and highly resistant to azithromycin. We report 2 new cases from France in 2023 involving strains genetically related to the 4 cases from Europe as well as isolates from Cambodia.

12.
Emerg Infect Dis ; 30(13): S62-S67, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38561843

RESUMO

We reviewed data obtained in October 2021-May 2023 from youth who reported a history of sexual activity upon admission to 1 of 12 juvenile justice facilities in Utah, USA, that offered screening for Chlamydia trachomatis and Neisseria gonorrhoeae. Urinalysis revealed C. trachomatis positivity of 10.77%, N. gonorrhoeae positivity of 1.08%, and coinfection C. trachomatis N. gonorrhoeae) of 0.90%. Prevalence of infection was similar for youths in rural and urban facilities. A total of 12.01% of those identifying as male and 14.01% of those identifying as female tested positive for C. trachomatis, N. gonorrhoeae, or coinfection. Of young adults who tested positive, 74.65% received their results while incarcerated, all of whom accepted treatment. Our research underscores the feasibility of providing prompt C. trachomatis/N. gonorrhoeae screening and treatment in juvenile correctional facilities. The pervasiveness of infection emphasizes the urgent need for early identification and treatment for C. trachomatis and N. gonorrhoeae in incarcerated youth nationwide.


Assuntos
Infecções por Chlamydia , Coinfecção , Gonorreia , Adulto Jovem , Adolescente , Masculino , Feminino , Humanos , Gonorreia/diagnóstico , Gonorreia/epidemiologia , Gonorreia/prevenção & controle , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/epidemiologia , Utah/epidemiologia , Coinfecção/epidemiologia , Neisseria gonorrhoeae , Chlamydia trachomatis , Estabelecimentos Correcionais , Prevalência , Programas de Rastreamento/métodos
13.
Emerg Infect Dis ; 30(2): 329-332, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38167386

RESUMO

After lifting of all COVID-19 preventive measures in England in July 2021, marked, widespread increases in gonorrhea diagnoses, but not testing numbers, were observed, particularly in persons 15-24 years of age. Continued close surveillance and public health messaging to young persons are needed to control and prevent gonorrhea transmission.


Assuntos
COVID-19 , Gonorreia , Humanos , COVID-19/prevenção & controle , Gonorreia/epidemiologia , Gonorreia/prevenção & controle , SARS-CoV-2 , Saúde Pública , Inglaterra/epidemiologia
14.
J Clin Microbiol ; 62(1): e0103923, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38084950

RESUMO

Supplementary nucleic acid amplification testing for Neisseria gonorrhoeae (NG) is widely used to circumvent specificity problems associated with extragenital sites. Here, we compared different supplementary approaches for confirming NG-positive samples from the cobas 4800 CT/NG (c4800) and cobas 6800 CT/NG (c6800) assays using the ResistancePlusGC (RP-GC) assay, which in addition to detecting NG, also predicts ciprofloxacin susceptibility via NG gyrA characterization. Two different nucleic acid extraction techniques were investigated for RP-GC detection; extracts from c4800 (c4800-RP-GC) and MagNA Pure 96 (MP96-RP-GC). NG-positive (n = 300) and -negative (n = 150) samples in cobas PCR media from routine c4800 testing were retrospectively retested with c4800, c6800, c4800-RP-GC, and MP96-RP-GC. Selected samples were also tested with Xpert CT/NG (Xpert) for discrepant analysis. The gyrA status was compared to ETEST ciprofloxacin susceptibility or non-susceptibility for recovered isolates (n = 63). Extragenital confirmatory rates were higher for MP96-RP-GC (131/140; 93.6%) compared to c4800-RP-GC (126/146; 86.3%), albeit not significantly (P = 0.6677). Of 9 samples testing positive by c6800 and negative by MP96-RP-GC, 7/9 (77.8%) were also negative by Xpert. By contrast, the number of samples returning a valid gyrA status was significantly (P = 0.0003) higher for MP96-RP-GC (270/293; 92.2%) compared to c4800-RP-GC (245/298; 82.2%). The overall MP96-RP-GC gyrA status correlated 98.4% (61/62) with the reported ciprofloxacin sensitive (35/36; 97.2%) or non-susceptible (26/26; 100%) phenotype. Improved RP-GC confirmatory rates and reported gyrA status were observed using MP96 nucleic acids compared to c4800 extracts. The data further highlight the ongoing need for NG supplemental testing for oropharyngeal samples.


Assuntos
Gonorreia , Ácidos Nucleicos , Humanos , Neisseria gonorrhoeae/genética , Ciprofloxacina/farmacologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X , Gonorreia/diagnóstico
15.
Biol Reprod ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38972067

RESUMO

With ~78 million cases yearly, the sexually transmitted bacterium Neisseria gonorrhoeae is an urgent threat to global public health due to continued emergence of antimicrobial resistance. In the male reproductive tract, untreated infections may cause permanent damage, poor sperm quality, and subsequently subfertility. Currently, few animal models exist for N. gonorrhoeae infection, which has strict human tropism, and available models have limited translatability to human disease. The absence of appropriate models inhibits the development of vital new diagnostics and treatments. However, the discovery of Neisseria musculi, a mouse oral cavity bacterium, offers much promise. This bacterium has already been used to develop an oral Neisseria infection model, but the feasibility of establishing urogenital gonococcal models is unexplored. We inoculated mice via the intrapenile route with N. musculi. We assessed bacterial burden throughout the male reproductive tract, the systemic and tissue-specific immune response 2-weeks postinfection, and the effect of infection on sperm health. Neisseria musculi was found in penis (2/5) and vas deferens (3/5) tissues. Infection altered immune cell counts: CD19+ (spleen, lymph node, penis), F4/80+ (spleen, lymph node, epididymus), and Gr1+ (penis) compared with noninfected mice. This culminated in sperm from infected mice having poor viability, motility, and morphology. We hypothesize that in the absence of testis infection, infection and inflammation in other reproductive is sufficient to damage sperm quality. Many results herein are consistent with outcomes of gonorrhoea infection, indicating the potential of this model as a tool for enhancing the understanding of Neisseria infections of the human male reproductive tract.

16.
Int J Med Microbiol ; 314: 151611, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309143

RESUMO

Numbers of infections with Neisseria gonorrhoeae are among the top three sexually transmitted infections (STI) worldwide. In addition, the emergence and spread of antimicrobial resistance (AMR) in Neisseria gonorrhoeae pose an important public-health issue. The integration of genomic, phenotypic and epidemiological data to monitor Neisseria gonorrhoeae fosters our understanding of the emergence and spread of AMR in Neisseria gonorrhoeae and helps to inform therapy guidelines and intervention strategies. Thus, the Gonococcal resistance surveillance (Go-Surv-AMR) was implemented at the Robert Koch Institute in Germany in 2021 to obtain molecular, phenotypic and epidemiological data on Neisseria gonorrhoeae isolated in Germany. Here, we describe the structure and aims of Go-Surv-AMR. Furthermore, we point out future directions of Go-Surv-AMR to improve the integrated genomic surveillance of Neisseria gonorrhoeae. In this context we discuss current and prospective sequencing approaches and the information derived from their application. Moreover, we highlight the importance of combining phenotypic and WGS data to monitor the evolution of AMR in Neisseria gonorrhoeae in Germany. The implementation and constant development of techniques and tools to improve the genomic surveillance of Neisseria gonorrhoeae will be important in coming years.


Assuntos
Gonorreia , Neisseria gonorrhoeae , Humanos , Neisseria gonorrhoeae/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Estudos Prospectivos , Farmacorresistência Bacteriana/genética , Testes de Sensibilidade Microbiana , Gonorreia/tratamento farmacológico , Gonorreia/epidemiologia , Alemanha/epidemiologia
17.
BMC Microbiol ; 24(1): 29, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245708

RESUMO

BACKGROUND: The ATP-dependent DNA ligase Lig E is present as an accessory DNA ligase in numerous proteobacterial genomes, including many disease-causing species. Here we have constructed a genomic Lig E knock-out in the obligate human pathogen Neisseria gonorrhoeae and characterised its growth and infection phenotype. RESULTS: This demonstrates that N. gonorrhoeae Lig E is a non-essential gene and its deletion does not cause defects in replication or survival of DNA-damaging stressors. Knock-out strains were partially defective in biofilm formation on an artificial surface as well as adhesion to epithelial cells. In addition to in vivo characterisation, we have recombinantly expressed and assayed N. gonorrhoeae Lig E and determined the crystal structure of the enzyme-adenylate engaged with DNA substrate in an open non-catalytic conformation. CONCLUSIONS: These findings, coupled with the predicted extracellular/ periplasmic location of Lig E indicates a role in extracellular DNA joining as well as providing insight into the binding dynamics of these minimal DNA ligases.


Assuntos
DNA Ligases , Neisseria gonorrhoeae , Humanos , DNA Ligase Dependente de ATP/genética , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/metabolismo , DNA Ligases/genética , DNA Ligases/química , DNA Ligases/metabolismo , DNA , Biofilmes
18.
Sex Transm Infect ; 100(1): 48-51, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38050184

RESUMO

OBJECTIVES: To ensure accurate diagnosis of infectious diseases, preanalytical factors should be considered when assessing specimen quality and subsequent test result. Accordingly, we aimed to systematically assess the effect of storage time, temperature and buffer on the analytical sensitivity of detecting the sexually transmitted pathogen, Neisseria gonorrhoeae across multiple molecular diagnostic platforms. METHODS: Cultured N. gonorrhoeae was spiked into generic and commercial storage buffers and stored at four temperatures and five time points, ranging from -20°C to 37°C, over 30 days. Samples were processed using the Alinity m STI, Xpert CT/NG and Aptima Combo 2 nucleic acid amplification assays and an in-house quantitative PCR assay. A reduction in analytical sensitivity was defined as a significant (p<0.05) increase in cycle threshold (Ct) value relative to control samples. RESULTS: In total, 2756 samples were processed, with N. gonorrhoeae detected in 99.2% of samples. With respect to time, analytical sensitivity was maintained from day 2 (113/120; 94.2%) up to day 30 (110/120; 91.7%) relative to baseline samples. With respect to temperature, analytical sensitivity was maintained from -20°C (147/150; 98.0%) up to 37°C (136/150; 90.7%) relative to baseline samples. Generic buffers, Viral Transport Medium and Amies Liquid Media showed a reduction in analytical sensitivity compared with their commercial counterparts, Aptima Multitest Swab Transport Media and Abbott Alinity transport buffer using select diagnostic assays; this reduction appeared temperature dependent, with the largest differences in median Ct values observed at 37°C (p<0.05). CONCLUSIONS: Increased prevalence of sample self-collection for sexually transmitted infections (STIs) warrants an evaluation of preanalytical sample storage variables on diagnostic testing performance. Here, across a range of time points, temperatures and storage buffers, N. gonorrhoeae was successfully detected, supporting flexibility in sample storage, and by extension the feasibility of analysing self-collected samples to improve access to STI testing.


Assuntos
Infecções por Chlamydia , Gonorreia , Ácidos Nucleicos , Infecções Sexualmente Transmissíveis , Humanos , Neisseria gonorrhoeae/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Chlamydia trachomatis/genética , Sensibilidade e Especificidade , Infecções por Chlamydia/diagnóstico , Gonorreia/diagnóstico
19.
Sex Transm Infect ; 100(1): 25-30, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-37945345

RESUMO

OBJECTIVES: Antimicrobial-resistant Neisseria gonorrhoeae (NG) is a concern. Little is known about antimicrobial susceptibility profiles and associated genetic resistance mechanisms of NG in Madagascar. We report susceptibility data of NG isolates obtained by the medical laboratory (CBC) of the Institut Pasteur de Madagascar, Antananarivo, Madagascar, during 2014-2020. We present antimicrobial resistance mechanisms data and phenotype profiles of a subset of isolates. METHODS: We retrieved retrospective data (N=395) from patients with NG isolated during 2014-2020 by the CBC. We retested 46 viable isolates including 6 found ceftriaxone and 2 azithromycin resistant, as well as 33 isolated from 2020. We determined minimal inhibitory concentrations for ceftriaxone, ciprofloxacin, azithromycin, penicillin, tetracycline and spectinomycin using Etest. We obtained whole-genome sequences and identified the gene determinants associated with antimicrobial resistance and the sequence types (STs). RESULTS: Over the study period, ceftriaxone-resistant isolates exceeded the threshold of 5% in 2017 (7.4% (4 of 54)) and 2020 (7.1% (3 of 42)). All retested isolates were found susceptible to ceftriaxone, azithromycin and spectinomycin, and resistant to ciprofloxacin. The majority were resistant to penicillin (83% (38 of 46)) and tetracycline (87% (40 of 46)). We detected chromosomal mutations associated with antibiotic resistance in gyrA, parC, penA, ponA, porB and mtrR genes. None of the retested isolates carried the mosaic penA gene. The high rate of resistance to penicillin and tetracycline is explained by the presence of bla TEM (94.7% (36 of 38)) and tetM (97.5% (39 of 40)). We found a high number of circulating multilocus STs. Almost half of them were new types, and one new type was among the four most predominant. CONCLUSIONS: Our report provides a detailed dataset obtained through phenotypical and genotypical methods which will serve as a baseline for future surveillance of NG. We could not confirm the occurrence of ceftriaxone-resistant isolates. Our results highlight the importance of implementing quality-assured gonococcal antimicrobial resistance surveillance in Madagascar.


Assuntos
Anti-Infecciosos , Gonorreia , Humanos , Neisseria gonorrhoeae , Ceftriaxona/farmacologia , Azitromicina/farmacologia , Espectinomicina/farmacologia , Estudos Retrospectivos , Madagáscar/epidemiologia , Antibacterianos/farmacologia , Gonorreia/tratamento farmacológico , Gonorreia/epidemiologia , Tetraciclina/farmacologia , Ciprofloxacina/farmacologia , Penicilinas/farmacologia , Anti-Infecciosos/farmacologia , Testes de Sensibilidade Microbiana , Genômica
20.
Sex Transm Infect ; 100(4): 222-225, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38553038

RESUMO

OBJECTIVES: We aimed to assess whether a self-collected oral rinse was non-inferior to clinician-collected oropharyngeal swabs to detect Neisseria gonorrhoeae (Ng) using culture and nucleic acid amplification tests (NAAT) among men who have sex with men (MSM), and whether Ng may still be detected in oral rinses for a minimum of 5 days after collection. METHODS: MSM with a positive Ng result in an oropharyngeal or pooled sample (oropharynx, urethra and anorectum) were approached. Clinician-collected oropharyngeal swabs and oral rinses (15 mL sterile water) were taken. Ng culture and NAAT (Abbott 2000m RealTime System CT/NG assay and in-house PCR) were performed. Diagnostic accuracy was assessed using sensitivity and specificity, and agreement between both techniques using Cohen's kappa statistic. Aliquots of positive oral rinses were left at room temperature for a minimum of 5 days and reanalysed using NAAT. Lastly, participants filled in a questionnaire to explore perceptions of both methods. RESULTS: We included 100 participants between June 2022 and October 2023. 45 individuals (45 of 100) had a positive Ng result in either the oral rinses (42 of 45, 93%) or the swabs (36 of 45, 80%). Sensitivity was higher for oral rinses than swabs (sensitivity=0.93/0.80, specificity=1.0/1.0, respectively) and agreement between both techniques was good (kappa=0.75, p<0.001). Of the 42 positive oral rinses, 37 remained positive after a minimum of 5 days (88.1%). Using culture, 18 individuals had a positive Ng result in either the oral rinses (8 of 18, 44%) or the swabs (16 of 18, 88%). Most participants found the oral rinse easy or very easy to use and would be willing to use the oral rinse for home-based sampling. CONCLUSION: We detected more oropharyngeal Ng infections via NAAT using oral rinses than swab samples. However, swabs were better than oral rinses for culturing Ng. Oral rinses might allow for home-based self-sampling to detect oropharyngeal Ng.


Assuntos
Gonorreia , Homossexualidade Masculina , Neisseria gonorrhoeae , Técnicas de Amplificação de Ácido Nucleico , Orofaringe , Sensibilidade e Especificidade , Manejo de Espécimes , Humanos , Masculino , Neisseria gonorrhoeae/isolamento & purificação , Neisseria gonorrhoeae/genética , Gonorreia/diagnóstico , Adulto , Orofaringe/microbiologia , Manejo de Espécimes/métodos , Bélgica , Técnicas de Amplificação de Ácido Nucleico/métodos , Pessoa de Meia-Idade , Uretra/microbiologia , Adulto Jovem
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