Tuberculous otitis media(TOM) is a rare manifestation caused by Mycobacterium tuberculosis with low incidence rates among extrapulmonary tuberculosis cases. Diagnosis is often delayed because of the presence of severa...Tuberculous otitis media(TOM) is a rare manifestation caused by Mycobacterium tuberculosis with low incidence rates among extrapulmonary tuberculosis cases. Diagnosis is often delayed because of the presence of several clinical manifestations and the high prevalence of secondary bacterial infections. Few reports have attributed secondary bacterial infections in patients with TOM to commensal Neisseria. Thus, understanding the pathogenic mechanisms and clinical features of commensal Neisseria is important, considering its recent presentation as an infection-causing pathogen. Neisseria mucosa is a commensal inhabitant in humans and is generally considered non-pathogenic but can cause infection in rare cases. Here, we report an atypical secondary infection caused by Neisseria mucosa in an 81-year-old woman with TOM being treated for pulmonary tuberculosis. Direct purulent otorrhea smear microscopy revealed no acid-fast bacilli using Ziehl-Neelsen staining, whereas the phagocytosis of gram-negative cocci by white blood cells was confirmed using Gram staining. Otorrhea culture revealed the growth of N. mucosa. Subsequently, M. tuberculosis infection in the otorrhea was identified using a culture-based method. Vigilance is critical for the early detection of TOM to prevent further complications. This report raises awareness regarding TOM and provides insight into the pathogenicity of N. mucosa in otitis media.展开更多
BACKGROUND Neisseria mucosa is a gram negative diplococcus belonging to the genus Neisseria found commonly in the upper respiratory tract.It is typically a commensal organism when it is parasitic on oral and nasal muc...BACKGROUND Neisseria mucosa is a gram negative diplococcus belonging to the genus Neisseria found commonly in the upper respiratory tract.It is typically a commensal organism when it is parasitic on oral and nasal mucosa.To our knowledge,it does not cause disease in healthy individuals with normal immunity,but can be pathogenic in those with impaired immune function or change in bacterial colonization site.Neisseria mucosa has been reported to cause bacterial meningitis,conjunctivitis,pneumonia,endocarditis,peritonitis and urethritis.However,peritoneal dialysis-related peritonitis caused by Neisseria mucosa is extremely rare in clinical practice,which has not previously been reported in China.CASE SUMMARY A 55-year-old female presented to the nephrology clinic with upper abdominal pain without apparent cause,accompanied by nausea,vomiting and diarrhea for two days.The patient had a history of Stage 5 chronic kidney disease for five years,combined with renal hypertension and renal anemia,and was treated with peritoneal dialysis for renal replacement therapy.The patient was subsequently diagnosed with peritoneal dialysis-related peritonitis.Routine examination of peritoneal dialysis fluid showed abdominal infection,and the results of microbial culture of the peritoneal dialysis fluid confirmed Neisseria mucosa.Imi-penem/cilastatin 1.0 g q12h was added to peritoneal dialysis fluid for anti-infection treatment.After 24 d,the patient underwent upper extremity arteriovenous fistulation.One month later,the patient was discharged home in a clinically stable state.CONCLUSION Peritonitis caused by Neisseria mucosa is rare.Patients with home-based self-dialysis cannot guarantee good medical and health conditions,and require education on self-protection.展开更多
Introduction: Meningitis caused by Neisseria meningitidis constitutes a burden for the countries in the meningitis belt of sub-Saharan in general and particularly for Burkina Faso. In 2019 the Diapaga health district ...Introduction: Meningitis caused by Neisseria meningitidis constitutes a burden for the countries in the meningitis belt of sub-Saharan in general and particularly for Burkina Faso. In 2019 the Diapaga health district experienced a meningitis epidemic due to N. meningitidis serogroup C. Methods: This is a cross-sectional study with a descriptive aim in the health district of Diapaga where all cases of meningitis were included in this work. Rapid diagnostic tests (RDTs), culture as well as real-time PCR were used for the biological analysis of cerebral spinal fluid (CSF) samples. Results: Of 155 CSF samples analysed, 42% (65/155) were tested positve. Of them, N. meningitidis C accounted for 83% of all positive cases. Likewise, all thirteen (13) NmC strains were susceptible to oxacillin, ceftriaxone, penicillin and chloramphenicol. All strains of NmC belonged to the sequence type (ST) 10 217 and to the clonal complex (CC) 10 217. These CCs belonged to the same variant PorA type: P1.21-15.16;FetA type: F1-7;PorB type: 3-463. Conclusion: Burkina Faso had known an epidemic of meningitis caused by NmC in 2019 in the health district of Diapaga. This outbreak was contained in time due to the performance of the epidemiological surveillance system which made it possible to investigate on time and introduce the vaccine against the pathogen NmC.展开更多
Background and Objectives: Mitigation of antibiotic resistant Neisseria gonorrhoeae has become a priority due to considerable health and economical disabilities it generates. In order to tackle the emergence of resist...Background and Objectives: Mitigation of antibiotic resistant Neisseria gonorrhoeae has become a priority due to considerable health and economical disabilities it generates. In order to tackle the emergence of resistant Neisseria gonorrhoeae, this study aimed to determine the prevalence and risk factors of penicillinase type β-lactamase-producing Neisseria gonorrheae among patients consulting for genital infectious disorders in two health-facilities in Yaounde, Cameroon. Materials and Method: A cross-sectional descriptive and analytical study was conducted over a 3-month period, from July 2<sup>nd</sup> to October 2<sup>nd</sup>, 2022. Vaginal and urethral secretions were collected. Biochemical identification tests were performed on colonies grown on chocolate agar + polyvitex using the Api NH gallery. The detection of penicillinases was equally performed using the API NH gallery and confirmed using the antimicrobial susceptibility testing. The Minimum Inhibitory Concentrations of some antibiotics were determined using the E-Test. Results: The results showed that out of the 198 patients sampled, 16 (8.08%) were positive for Neisseria gonorrhoeae, among which 13/16 (81.25%) were penicillinase-type β-lactamase producers. Antimicrobial susceptibility testing results showed high co-resistances to antibiotics, mainly ciprofloxacin (100%), nalidixic acid (92.31%) and azithromycin (84.62%). Moreover, high Minimum Inhibitory Concentrations of ceftriaxone (ranging from 6 to 24 mg/L) was observed toward Neisseria gonorrhoeae isolates. The risk factors of the carriage of penicillinase-type β-lactamase producing Neisseria gonorrhoeae identified were: a history of Sexually Transmitted infections (p = 0.01) and unprotected sexual intercourse (p = 0.01). Conclusion: The emergence of penicillinase-type β-lactamase producing Neisseria gonorrhoeae is increasing and the situation is becoming worrisome. The identified risk factors can constitute a basic outlook to tackle resistant Neisseria gonorrhoeae, and therefore sustain antibiotic stewardship.展开更多
Objective To characterize the meningococcal strains isolated from cases and close contacts with meningococcal disease associated with an outbreak in a jail in May 2010 by investigating the national distribution of hyp...Objective To characterize the meningococcal strains isolated from cases and close contacts with meningococcal disease associated with an outbreak in a jail in May 2010 by investigating the national distribution of hyperinvasive ST-4821 serogroup C clone associated with this outbreak. Methods The cases were described based on the clinical symptoms and laboratory results. Pharyngeal swabs were cultured for N. meningitidis from men in the jail. Meningococcal isolates were identified by serogrouping, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST), respectively. Four hundred and sixteen serogroup C N. meningitidis strains were collected from 27 provinces between 2003 and 2010 for a nationwide survey and analyzed by PFGE and MLST. Results Three persons in a jail system were infected with invasive N. meningitidis serogroup C. All isolates tested had matching PFGE patterns and belonged to the multilocus sequence type (ST) 4821 clonal complex. All 47 N. meningitidis strains were identified from the pharyngeal swabs of 166 peoples in the jail, and 26 of them belonged to ST-4821 serogroup C clone, and 90.14% (375/416) serogroup C strains identified in the nationwide survey belonged to the ST-4821 complex. The ST-4821 serogroup C clone was spread nationwide, distributed in 24 provinces, especially in eastern provinces between 2003 and 2010. Conclusion Endemic transmission and carriage rate of ST-4821 serogroup C clone are high in this jail system. The ST-4821 serogroup C clone is spreading in China and nationwide distributed despite the existence of some effective vaccines.展开更多
Objective: To estimate the prevalence of antibiotic resistance of Neisseria species in Iran. Methods: A systematic and electronic search using relevant keywords in major national and international databases was perfor...Objective: To estimate the prevalence of antibiotic resistance of Neisseria species in Iran. Methods: A systematic and electronic search using relevant keywords in major national and international databases was performed until 6th July, 2018 in order to find studies reporting the prevalence of antibiotic resistance of Neisseria species in Iran. Results: A total of nine studies were found to be eligible based on predefined inclusion and exclusion criteria. Our analysis indicated that the prevalence of Neisseria gonorrhoeae resistance to different antibiotics was as follows: 66.9% to penicillin, 59.1% to ciprofloxacin, 11.1% to ceftriaxone, 21.6% to spectinomycin, 13.8% to cefixime, 82.4% to co-trimoxazole, 52.7% to tetracycline, 29.9% to gentamicin, 87.5% to ampicillin, 11.1% to azithromycin, 2.2% to chloramphenicol, 50.1% to cefepime and 50.0% to vancomycin. Antimicrobial resistance rates of Neisseria meningitidis was as follows: 30.0% to penicillin, 33.3% to amoxicillin, 33.3% to cephalexin, 55.6% to ampicillin and 0.0% to ciprofloxacin, ceftriaxone, cefotaxime, amikacin, co-trimoxazole, gentamicin, kanamycin, chloramphenicol and ceftizoxime. Conclusion: Neisseria gonorrhoeae and Neisseria meningitidis isolates of Iran show resistance to different types of antibiotics. Therefore, care should be exercised for the use of penicillin, ciprofloxacin, co-trimoxazole, tetracycline, gentamicin, ampicillin, cefepime and vancomycin for gonococcal infections, and also with respect to the use of penicillin, amoxicillin, ampicillin and cephalexin for meningococcal infections in Iran.展开更多
Neisseria meningitides is a Gram-negative bacterium which is an important causative agent of septicemia and meningitis.Numerous pathogenic bacteria contain luxS,which is required for autoinducer-2 production.Neisseria...Neisseria meningitides is a Gram-negative bacterium which is an important causative agent of septicemia and meningitis.Numerous pathogenic bacteria contain luxS,which is required for autoinducer-2 production.Neisseria meningitides contains a functional copy of luxS that is necessary for full meningococcal virulence.Neisseria meningitides DNA was extracted and its luxS gene was amplified by nested PCR.PCR product was purified and cloned in to pQE-30 expression vector.Recombinant plasmid was transformed and mass cultured.luxS was expressed in E.coli and confirmed by western blot analysis.In this study,N.meningitides luxS was amplified, cloned and expressed successfully.The sequencing of PCR product confirmed that amplified gene was luxS. Gene was expressed and observed in SDS-PAGE.Protein was reacted by his tag monoclonal antibody through western blot analysis.展开更多
Infectious conjunctivitis is a very common presentation to medical professional and ophthalmologist all over the world.Although its typically self-limiting and treatable in almost all of the cases,but we need to be aw...Infectious conjunctivitis is a very common presentation to medical professional and ophthalmologist all over the world.Although its typically self-limiting and treatable in almost all of the cases,but we need to be aware of the rare and potentially life threatening if the cause is not promptly identified and treated accordingly.In our case report,we highlighted the rare case of Neisseria meningitidis as a primary cause of keratoconjunctivitis.Neisseria meningitidis is a rare etiology of keratoconjunctivitis and its ocular presentations are quite similar with other bacterial or viral infection.The infection may potentially fatal if systemic invasion occurred,however with immediate and proper treatment the outcome is satisfactory.Early diagnosis and proper antibiotic treatment are critical to prevent systemic spread of the infection.Public health intervention is needed to prevent outbreak of the disease.展开更多
Objective:To determine the antimicrobial susceptibility and serotypes of Neisseria(N.)meningitidis and Streptococcus(S.)pneumoniae in Sri Lankan patients.Methods:We retrospectively analyzed 11 blood culture specimens ...Objective:To determine the antimicrobial susceptibility and serotypes of Neisseria(N.)meningitidis and Streptococcus(S.)pneumoniae in Sri Lankan patients.Methods:We retrospectively analyzed 11 blood culture specimens from suspected patients with invasive meningococcal disease and 26 S.pneumoniae clinical isolates.We tested 6 antimicrobials against N.meningitidis and 12 antimicrobials against S.pneumoniae.Meningococcal serogroup was determined by realtime PCR and Quellung serotyping was used for pneumococcal analysis.Results:N.meningitidis serogroup B was the most common in this study.Intermediate-susceptibility to penicillin was seen in 75.0%(6/8)of strains.Susceptibility to ciprofloxacin,levofloxacin and cotrimoxazole was 62.5%(5/8),62.5%(5/8)and 87.5%(7/8),respectively.Excellent susceptibility was seen in cefotaxime and meropenem.In S.pneumoniae,the most common serotype was 19F in both invasive and non-invasive pneumococcal diseases.The majority of strains showed multidrug resistance.Penicillin non-susceptibility in non-meningeal strains were 13.6%and all meningeal strains were penicillin resistant.Erythromycin was highly resistant in both groups.Amoxicillin showed excellent susceptibility in non-invasive pneumococcal diseases strains.Linezolid,levofloxacin and vancomycin showed 100.0%susceptibility in all pneumococcal isolates.Conclusions:Implementation of vaccines should be considered,especially for children and high-risk populations.This may contribute to reducing pneumococcal and meningococcal invasive disease burden and help prevent emergence of antimicrobial resistant strains.展开更多
One of the new strategies for the prevention of HIV acquisition is the use of microbicides such as topical microbicides including antimicrobial and antiviral peptides. Ideally, new drug candidates should kill pathogen...One of the new strategies for the prevention of HIV acquisition is the use of microbicides such as topical microbicides including antimicrobial and antiviral peptides. Ideally, new drug candidates should kill pathogens without determent to the normal bacterial flora considered important in health;such as hydrogen peroxide producing Lactobacillus species. The antimicrobial peptides LL-37 and LSA-5 were studied to determine their spectrum of activity against bacterial pathogens and normal flora organisms. The effects of divalent cations at biologically relevant concentrations were determined. We show the synthetic lytic peptide LSA-5 and the naturally occurring peptides LL-37 inactivate Neisseria gonorrhoeae but are less active against many normal flora members such as Lactobacillus species. Biologically relevant concentrations of calcium and magnesium prevented killing of sensitive strains. LSA-5 is more potent than LL-37, both are inhibited from killing sensitive strains by calcium and magnesium. Strains of Lactobacillus iners were killed by both microbicides even in the presence of the divalent cations. Antimicrobial peptides, such as LSA-5, have good potential for use in prevention of sexually transmitted disease, if formulated to sequester calcium and magnesium present in biological fluids.展开更多
In this study, we investigate the potential for oral Lactobacilli (LB) to afford innate protection against nasopharyngeal coloniser Neisseria meningitidis serogroup B (NmB), which causes the bulk of UK meningococcal d...In this study, we investigate the potential for oral Lactobacilli (LB) to afford innate protection against nasopharyngeal coloniser Neisseria meningitidis serogroup B (NmB), which causes the bulk of UK meningococcal disease. Oral isolates of L. plantarum, L. salivarious, L. casei, L. rhamnosus, L. gasseri and gut probiotic L. rhamnosus GG were assessed for their ability to suppress nasopharyngeal epithelial inflammatory responses to pathogenic NmB. The specificity of attenuation was examined using TLR 2 ligand, Pam3Cys, and early response cytokine IL1β;and the mechanism of attenuation was explored using heat-killed organisms and conditioned medium. Pro-inflammatory IL-6 and TNFα cytokine secretion was quantified by ELISA and associated cell death was quantified by PI staining and LDH release. NmB adhesion, invasion and metabolism were determined using standard gentamicin protection with viable counts, and bioluminescence, respectively. L. plantarum and L. salivarious suppressed IL-6 and TNFα secretions from NmB-infected epithelial cells. LB did not need to be alive and could suppress using secretions, which were independent of TLR2 or IL1β receptor signalling. L. plantarum, in particular, reduced NmB-induced necrotic cell death of epithelial monolayers. Like L. salivarious, it significantly inhibited NmB adhesion but uniquely L. plantarum abolished NmB invasion. Using bioluminescence as a reporter of pathogen metabolism, L. plantarum and its secretions were found to inhibit NmB metabolism during cell invasion assays. We conclude that oral L. plantarum and its secretions could be used to help reduce the burden of meningococcal disease by removing the intracellular nasopharyngeal reservoir of NmB.展开更多
Chlamydial and gonococcal infections are recognized as two of the major causes of sexually transmissible human bacterial infection which may lead to infertility. In this cross sectional study, we aimed to determine th...Chlamydial and gonococcal infections are recognized as two of the major causes of sexually transmissible human bacterial infection which may lead to infertility. In this cross sectional study, we aimed to determine the prevalence of Neisseria gonorrhoeae, Chlamydia trachomatis among Egyptian women using different microbiological methods. One hundred and fifty cervical swabs were collected, of which 100 were from infertile women. Culture and ELISA technique were used for screening of Neisseria gonorrhoeae and Chlamydia trachomatis individually. In addition, PCR was used for all examined samples. For C. trachomatis, 3 cases were positive for antigen detection by ELISA. Moreover, in obtained results of PCR, DNA was detected in 4 samples, and three of them from infertile group. So based on PCR results, the sensitivity and specificity of ELISA were 75% and 100% respectively. Furthermore, 3 samples were positive for gonococcal infections by PCR, and two of them were taken from infertile women. Positive results of two samples were verified by culture. The estimated sensitivity and specificity of culture method were 66.7% and 100% respectively. Results of this study indicate that PCR is a valuable method for detection of gonococcal and chlamydial infection and it is suitable for the confirmation of ELISA results for C. trachomatis diagnosis. Culture method is less sensitive than PCR for detection of N. gonorrhoeae. The prevalence of such infections is higher among infertile women.展开更多
Neisseria meningitidis(N.meningitidis) is an exclusively human pathogen that has been identified in 10%-35% of the adult population and in 5.9% of the child population.Despite the high prevalence of carriers of N.meni...Neisseria meningitidis(N.meningitidis) is an exclusively human pathogen that has been identified in 10%-35% of the adult population and in 5.9% of the child population.Despite the high prevalence of carriers of N.meningitidis,it only occasionally causes meningococcal disease in the context of endemic disease,in certain geographic areas or in isolated epidemic outbreaks.After the N.meningitidis genome is described,progress has been made toward understanding the pathogenic mechanisms of the bacteria,although some aspects concerning its interaction with the environment and the host remain unclear.Some studies have reported that oxidative stress in the environment can modify the surface characteristics of N.meningitidis,increasing its adhesive properties and favouring an asymptomaticcarrier state.The antigenic structure of N.meningitidis can be modified by its importing genetic material from other bacteria in its ecological niche.Some structures of lipopolysaccharides help it to evade the immune response,and these are observed more frequently in N.meningitidis isolated from blood than in healthy nasopharyngeal carriers.There is evidence that pili and capsule are downregulated upon contact with target cells.This paper reviews current knowledge on hostenvironment-bacteria mechanisms and interactions,with the aim of contributing to our understanding of the pathogenic mechanisms of N.meningitidis.展开更多
Background:Neisseria gonorrhoeae is a gram-negative diplococcus that leads to sexually transmitted infection.N.gonorrhoeae is an obligate human pathogen that causes infection to the mucus-secreting epithelial cells bo...Background:Neisseria gonorrhoeae is a gram-negative diplococcus that leads to sexually transmitted infection.N.gonorrhoeae is an obligate human pathogen that causes infection to the mucus-secreting epithelial cells both in males and females.In 2017 the center for disease control and the World Health Organization published the list of global priority pathogens-12 with denting therapeutic options,including antibiotic-resistant N.gonorrhoeae.Methods:we thoroughly characterized zoliflodacin antibiotic,its clinical trials and effect on human health by using different keywords like“zoliflodacin”,“COVID-19”,“clinical trials”from different data sources like Pub-Med,Google-Scholar,and Science-Direct.Results:Zoliflodacin shows a therapeutic approach against N.gonorrhoeae.It acts by inhibiting bacterial type 2 topoisomerase with the binding sites in bacterial gyrase.It shows promising results against N.gonorrhoeae.Zoliflodacin is effective in treating gonococcal urogenital and rectal infection.Conclusion:Currently,antibiotic is the only option to treat N.gonorrhoeae with no vaccine available to treat it.The new drug,zoliflodacin,specifically targets antibiotic-resistant gonorrhea and it has given a hope to researchers.This review elaborates the discovery of zoliflodacin,its mechanism of action,current clinical trials,and its effectiveness.展开更多
To identify the genomic species of Neisseria gonorrhoeae, evaluate the difference between two molecular epidemiological methods and examine the relationship between sex partners and genotypes of bacteria, 24 strains o...To identify the genomic species of Neisseria gonorrhoeae, evaluate the difference between two molecular epidemiological methods and examine the relationship between sex partners and genotypes of bacteria, 24 strains of Neisseria gonorrhoeae isolated from the outpatients with gonorrhea were identified by using the Opa genotyping and NG-MAST genotyping and the relationship between genotypes and phenotypes was studied. Twenty-four strains of Neisseria gonorrhoeae fell into 10 ST genotypes by NG-MAST genotyping, whereas these strains were classified into 12 OT Opa genotypes by Opa genotyping. A new epidemic strain of ST genotype (217-86% homologisation 178) in China was identified. It is concluded that genotypes of each pair of strains from a pair of patient/sex partner besides 45/46 are the same, indicating that contagious infection take place between patient and the sex partner. Opa genotyping was more effective than NG-MAST genotyping in identifying the genomic species of Neisseria gonorrhoeae. ST genotype could be further classified into different Opa-types.展开更多
In order to study the resistance of Neisseria (N.) gonorrhoeae to the fluoroquinolone and detect mutation patterns of quinolone resistance-determining regions (QRDRs) of clinical isolates in Shanghai, China, a total o...In order to study the resistance of Neisseria (N.) gonorrhoeae to the fluoroquinolone and detect mutation patterns of quinolone resistance-determining regions (QRDRs) of clinical isolates in Shanghai, China, a total of 80 clinical isolates of N. gonorrhoeae were consecutively collected from Shanghai. The MIC of fluoroquinolone for the isolates was examined by using the agar dilution method and the mutation profiles of the QRDRs of gyrA and parC were analyzed by sequencing and restriction fragment length polymorphism (RFLP). Chi-square test was used for comparison of the mutation patterns. The results showed that: (1) High percentages of the 8 isolates were resistant to ciprofloxacin (95.0%), ofloxacin (95.0%) and lomefloxacin (97.5%), only one strain was susceptible to the ciprofloxacin. (2) Sensitive strains had a substitute of Asp95→Ala in the gyrA, and all isolates that were resistant or intermediated to the ciprofloxacin, had a double mutation in the gyrA (Ser91, Ala 92 and Asp95). Some strains also had a mutation in the parC. (3) The MICs of these isolates were significantly associated with the mutation patterns in the gyrA and parC. A double mutation of gyrA combined with parC87 mutation was a predominant pattern in Shanghai and could mediate high level resistance to ciprofloxacin. It suggests that mutations in the QRDRs of gyrA and parC may be re-sponsible for the fluoroquinolone resistance. And fluoroquinolone could not be used as the first line antibiotics for gonorrhea treatment any more in Shanghai, China.展开更多
To study the relationship between mutation of the inverted repeat sequence (IR) in the multiple transferable resistant system (mtr) of Neisseria gonorrhoeae (NG) and its multiple antibiotic resistance, minimal inhibit...To study the relationship between mutation of the inverted repeat sequence (IR) in the multiple transferable resistant system (mtr) of Neisseria gonorrhoeae (NG) and its multiple antibiotic resistance, minimal inhibitory concentrations (MICs) for the clinically isolated strains were tested by agar-dilution-method. The mtr system’s IR gene of NG was sequenced after amplification by polymerase chain reaction (PCR). Either two susceptive or five penicillin-resistant strains had no base mutation in IR gene, while all of the 13 strains with multiple-antibiotic-resistance had a single-base deletion (A/T). The result suggests that a single-base deletion of the thirteen-base IR sequence in mtr system of NG might result in multiple antibiotic resistance but is not associated with single antibiotic resistance.展开更多
Objective During 2003-2005, an outbreak of meningitis due to Neisseria meningitidis serogroup C occurred in China. With the aim to find strain clues result in the final epidemics, the ancestral strain 053442, a clinic...Objective During 2003-2005, an outbreak of meningitis due to Neisseria meningitidis serogroup C occurred in China. With the aim to find strain clues result in the final epidemics, the ancestral strain 053442, a clinical isolate, and a carrier strain 053426 with different gene type were analyzed. Methods Clinical strain 053442 and carrier strain 053426 were cultured on GC agar plates under the same condition. Two-dimensional electrophoresis was performed using the pH 3-10 nonlinear IPG strips of 24 cm length, and all the protein spots were identified by matrix-assisted laser desorption/ionization time of flight spectrometry. Results 502 and 380 protein spots were identified in 053426 and 053442 respectively, relating to 266 and 202 different genes covering a wide range of cellular functions. The express volume and number of proteins involved in energy metabolism, protein synthesis and amino acid biosynthesis in 053426 were higher than in 053442. Virulence factor Opa, Opc and a series of proteins involved in pilus assembly and retraction were identified in 053442, which appear to be of primary importance in colonization and invasion of human cells. Compared to 053442, virulence protein species were less in 053426, with lower express volumes too. No Opa and Opc were detected in 053426. Conclusion The different protein expression profiles of the clinical strain 053442 and carrier strain 053426 in the present study provide some clues of the different pathogenicity of the two strains, which may account for result in the final epidemics.展开更多
In order to provide a rational research basis for detection of resistance of Neisseria gonorrhoeae to antimicrobial hydrophobic agents and study on the resistant mechanism of multiple transferable resistance (mtr) eff...In order to provide a rational research basis for detection of resistance of Neisseria gonorrhoeae to antimicrobial hydrophobic agents and study on the resistant mechanism of multiple transferable resistance (mtr) efflux system, plasmid pET-28a(+) encoding mtrC gene was constructed and the related target protein was expressed in Escherichia coli(E.coli) DE3. The fragments of mtrC gene of Neisseria gonorrhoeae from the standard strains were amplified and cloned into prokaryotic expression plasmid pET-28a(+) with restriction endonuclease to construct recombinant pET-mtrC which was verified by restriction endonuclease and DNA sequencing. The recombinant was transformed into E.coli DE3 to express the protein mtrC induced by IPTG. The results showed mtrC DNA fragment was proved correct through restriction endonuclease and DNA sequencing. Its sequence was 99.5 % homologus to that published on GeneBank (U14993). A 48.5 kD fusion protein which was induced by IPTG was detected by SDS-PAGE. It was concluded that the construction of prokaryotic expression plasmid of mtrC protein of Neisseria gonorrhoeae was correct and the fusion protein was successively expressed in E.coli.展开更多
Objective: To investigate the serotypes and auxotypes distribution of Neisseria gonorrhoeae in Guangzhou. Method: 131 strains of Neisseria gonorrhoeae were serotyped by co-agglutination test and 108 strains were auxot...Objective: To investigate the serotypes and auxotypes distribution of Neisseria gonorrhoeae in Guangzhou. Method: 131 strains of Neisseria gonorrhoeae were serotyped by co-agglutination test and 108 strains were auxotyped by La Scolea's method. Results: Out of 131 strains of Neisseria gonorrhoeae ,87.8% (115/131) were WⅡ/WⅢ, while 9.9% (131131) were WI. The most important auxotypes were Proto, Pro and ILe,42.6% (46/108), 21.3% (23/108) and 12.0%, respectively. WII/WIII was distributed among the all auxotypes aboveand WⅠ found only in both Proto and Pro. Conclusion: The study illustrated the prevailing serotype,WⅡ/WⅢ, and higher prevalence of Ile- in Guangzhou.展开更多
文摘Tuberculous otitis media(TOM) is a rare manifestation caused by Mycobacterium tuberculosis with low incidence rates among extrapulmonary tuberculosis cases. Diagnosis is often delayed because of the presence of several clinical manifestations and the high prevalence of secondary bacterial infections. Few reports have attributed secondary bacterial infections in patients with TOM to commensal Neisseria. Thus, understanding the pathogenic mechanisms and clinical features of commensal Neisseria is important, considering its recent presentation as an infection-causing pathogen. Neisseria mucosa is a commensal inhabitant in humans and is generally considered non-pathogenic but can cause infection in rare cases. Here, we report an atypical secondary infection caused by Neisseria mucosa in an 81-year-old woman with TOM being treated for pulmonary tuberculosis. Direct purulent otorrhea smear microscopy revealed no acid-fast bacilli using Ziehl-Neelsen staining, whereas the phagocytosis of gram-negative cocci by white blood cells was confirmed using Gram staining. Otorrhea culture revealed the growth of N. mucosa. Subsequently, M. tuberculosis infection in the otorrhea was identified using a culture-based method. Vigilance is critical for the early detection of TOM to prevent further complications. This report raises awareness regarding TOM and provides insight into the pathogenicity of N. mucosa in otitis media.
文摘BACKGROUND Neisseria mucosa is a gram negative diplococcus belonging to the genus Neisseria found commonly in the upper respiratory tract.It is typically a commensal organism when it is parasitic on oral and nasal mucosa.To our knowledge,it does not cause disease in healthy individuals with normal immunity,but can be pathogenic in those with impaired immune function or change in bacterial colonization site.Neisseria mucosa has been reported to cause bacterial meningitis,conjunctivitis,pneumonia,endocarditis,peritonitis and urethritis.However,peritoneal dialysis-related peritonitis caused by Neisseria mucosa is extremely rare in clinical practice,which has not previously been reported in China.CASE SUMMARY A 55-year-old female presented to the nephrology clinic with upper abdominal pain without apparent cause,accompanied by nausea,vomiting and diarrhea for two days.The patient had a history of Stage 5 chronic kidney disease for five years,combined with renal hypertension and renal anemia,and was treated with peritoneal dialysis for renal replacement therapy.The patient was subsequently diagnosed with peritoneal dialysis-related peritonitis.Routine examination of peritoneal dialysis fluid showed abdominal infection,and the results of microbial culture of the peritoneal dialysis fluid confirmed Neisseria mucosa.Imi-penem/cilastatin 1.0 g q12h was added to peritoneal dialysis fluid for anti-infection treatment.After 24 d,the patient underwent upper extremity arteriovenous fistulation.One month later,the patient was discharged home in a clinically stable state.CONCLUSION Peritonitis caused by Neisseria mucosa is rare.Patients with home-based self-dialysis cannot guarantee good medical and health conditions,and require education on self-protection.
文摘Introduction: Meningitis caused by Neisseria meningitidis constitutes a burden for the countries in the meningitis belt of sub-Saharan in general and particularly for Burkina Faso. In 2019 the Diapaga health district experienced a meningitis epidemic due to N. meningitidis serogroup C. Methods: This is a cross-sectional study with a descriptive aim in the health district of Diapaga where all cases of meningitis were included in this work. Rapid diagnostic tests (RDTs), culture as well as real-time PCR were used for the biological analysis of cerebral spinal fluid (CSF) samples. Results: Of 155 CSF samples analysed, 42% (65/155) were tested positve. Of them, N. meningitidis C accounted for 83% of all positive cases. Likewise, all thirteen (13) NmC strains were susceptible to oxacillin, ceftriaxone, penicillin and chloramphenicol. All strains of NmC belonged to the sequence type (ST) 10 217 and to the clonal complex (CC) 10 217. These CCs belonged to the same variant PorA type: P1.21-15.16;FetA type: F1-7;PorB type: 3-463. Conclusion: Burkina Faso had known an epidemic of meningitis caused by NmC in 2019 in the health district of Diapaga. This outbreak was contained in time due to the performance of the epidemiological surveillance system which made it possible to investigate on time and introduce the vaccine against the pathogen NmC.
文摘Background and Objectives: Mitigation of antibiotic resistant Neisseria gonorrhoeae has become a priority due to considerable health and economical disabilities it generates. In order to tackle the emergence of resistant Neisseria gonorrhoeae, this study aimed to determine the prevalence and risk factors of penicillinase type β-lactamase-producing Neisseria gonorrheae among patients consulting for genital infectious disorders in two health-facilities in Yaounde, Cameroon. Materials and Method: A cross-sectional descriptive and analytical study was conducted over a 3-month period, from July 2<sup>nd</sup> to October 2<sup>nd</sup>, 2022. Vaginal and urethral secretions were collected. Biochemical identification tests were performed on colonies grown on chocolate agar + polyvitex using the Api NH gallery. The detection of penicillinases was equally performed using the API NH gallery and confirmed using the antimicrobial susceptibility testing. The Minimum Inhibitory Concentrations of some antibiotics were determined using the E-Test. Results: The results showed that out of the 198 patients sampled, 16 (8.08%) were positive for Neisseria gonorrhoeae, among which 13/16 (81.25%) were penicillinase-type β-lactamase producers. Antimicrobial susceptibility testing results showed high co-resistances to antibiotics, mainly ciprofloxacin (100%), nalidixic acid (92.31%) and azithromycin (84.62%). Moreover, high Minimum Inhibitory Concentrations of ceftriaxone (ranging from 6 to 24 mg/L) was observed toward Neisseria gonorrhoeae isolates. The risk factors of the carriage of penicillinase-type β-lactamase producing Neisseria gonorrhoeae identified were: a history of Sexually Transmitted infections (p = 0.01) and unprotected sexual intercourse (p = 0.01). Conclusion: The emergence of penicillinase-type β-lactamase producing Neisseria gonorrhoeae is increasing and the situation is becoming worrisome. The identified risk factors can constitute a basic outlook to tackle resistant Neisseria gonorrhoeae, and therefore sustain antibiotic stewardship.
基金supported by Research Fund from Ministry of Health and Ministry of Science and Technology of the People’s Republic of China,2013ZX10004221,2012ZX10004215,and 2011CB504900
文摘Objective To characterize the meningococcal strains isolated from cases and close contacts with meningococcal disease associated with an outbreak in a jail in May 2010 by investigating the national distribution of hyperinvasive ST-4821 serogroup C clone associated with this outbreak. Methods The cases were described based on the clinical symptoms and laboratory results. Pharyngeal swabs were cultured for N. meningitidis from men in the jail. Meningococcal isolates were identified by serogrouping, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST), respectively. Four hundred and sixteen serogroup C N. meningitidis strains were collected from 27 provinces between 2003 and 2010 for a nationwide survey and analyzed by PFGE and MLST. Results Three persons in a jail system were infected with invasive N. meningitidis serogroup C. All isolates tested had matching PFGE patterns and belonged to the multilocus sequence type (ST) 4821 clonal complex. All 47 N. meningitidis strains were identified from the pharyngeal swabs of 166 peoples in the jail, and 26 of them belonged to ST-4821 serogroup C clone, and 90.14% (375/416) serogroup C strains identified in the nationwide survey belonged to the ST-4821 complex. The ST-4821 serogroup C clone was spread nationwide, distributed in 24 provinces, especially in eastern provinces between 2003 and 2010. Conclusion Endemic transmission and carriage rate of ST-4821 serogroup C clone are high in this jail system. The ST-4821 serogroup C clone is spreading in China and nationwide distributed despite the existence of some effective vaccines.
文摘Objective: To estimate the prevalence of antibiotic resistance of Neisseria species in Iran. Methods: A systematic and electronic search using relevant keywords in major national and international databases was performed until 6th July, 2018 in order to find studies reporting the prevalence of antibiotic resistance of Neisseria species in Iran. Results: A total of nine studies were found to be eligible based on predefined inclusion and exclusion criteria. Our analysis indicated that the prevalence of Neisseria gonorrhoeae resistance to different antibiotics was as follows: 66.9% to penicillin, 59.1% to ciprofloxacin, 11.1% to ceftriaxone, 21.6% to spectinomycin, 13.8% to cefixime, 82.4% to co-trimoxazole, 52.7% to tetracycline, 29.9% to gentamicin, 87.5% to ampicillin, 11.1% to azithromycin, 2.2% to chloramphenicol, 50.1% to cefepime and 50.0% to vancomycin. Antimicrobial resistance rates of Neisseria meningitidis was as follows: 30.0% to penicillin, 33.3% to amoxicillin, 33.3% to cephalexin, 55.6% to ampicillin and 0.0% to ciprofloxacin, ceftriaxone, cefotaxime, amikacin, co-trimoxazole, gentamicin, kanamycin, chloramphenicol and ceftizoxime. Conclusion: Neisseria gonorrhoeae and Neisseria meningitidis isolates of Iran show resistance to different types of antibiotics. Therefore, care should be exercised for the use of penicillin, ciprofloxacin, co-trimoxazole, tetracycline, gentamicin, ampicillin, cefepime and vancomycin for gonococcal infections, and also with respect to the use of penicillin, amoxicillin, ampicillin and cephalexin for meningococcal infections in Iran.
基金supported by Vice Chancellor of Research of Shahid Beheshti University M.C.and was done in Cellular and Molecular Biology Research Center
文摘Neisseria meningitides is a Gram-negative bacterium which is an important causative agent of septicemia and meningitis.Numerous pathogenic bacteria contain luxS,which is required for autoinducer-2 production.Neisseria meningitides contains a functional copy of luxS that is necessary for full meningococcal virulence.Neisseria meningitides DNA was extracted and its luxS gene was amplified by nested PCR.PCR product was purified and cloned in to pQE-30 expression vector.Recombinant plasmid was transformed and mass cultured.luxS was expressed in E.coli and confirmed by western blot analysis.In this study,N.meningitides luxS was amplified, cloned and expressed successfully.The sequencing of PCR product confirmed that amplified gene was luxS. Gene was expressed and observed in SDS-PAGE.Protein was reacted by his tag monoclonal antibody through western blot analysis.
文摘Infectious conjunctivitis is a very common presentation to medical professional and ophthalmologist all over the world.Although its typically self-limiting and treatable in almost all of the cases,but we need to be aware of the rare and potentially life threatening if the cause is not promptly identified and treated accordingly.In our case report,we highlighted the rare case of Neisseria meningitidis as a primary cause of keratoconjunctivitis.Neisseria meningitidis is a rare etiology of keratoconjunctivitis and its ocular presentations are quite similar with other bacterial or viral infection.The infection may potentially fatal if systemic invasion occurred,however with immediate and proper treatment the outcome is satisfactory.Early diagnosis and proper antibiotic treatment are critical to prevent systemic spread of the infection.Public health intervention is needed to prevent outbreak of the disease.
文摘Objective:To determine the antimicrobial susceptibility and serotypes of Neisseria(N.)meningitidis and Streptococcus(S.)pneumoniae in Sri Lankan patients.Methods:We retrospectively analyzed 11 blood culture specimens from suspected patients with invasive meningococcal disease and 26 S.pneumoniae clinical isolates.We tested 6 antimicrobials against N.meningitidis and 12 antimicrobials against S.pneumoniae.Meningococcal serogroup was determined by realtime PCR and Quellung serotyping was used for pneumococcal analysis.Results:N.meningitidis serogroup B was the most common in this study.Intermediate-susceptibility to penicillin was seen in 75.0%(6/8)of strains.Susceptibility to ciprofloxacin,levofloxacin and cotrimoxazole was 62.5%(5/8),62.5%(5/8)and 87.5%(7/8),respectively.Excellent susceptibility was seen in cefotaxime and meropenem.In S.pneumoniae,the most common serotype was 19F in both invasive and non-invasive pneumococcal diseases.The majority of strains showed multidrug resistance.Penicillin non-susceptibility in non-meningeal strains were 13.6%and all meningeal strains were penicillin resistant.Erythromycin was highly resistant in both groups.Amoxicillin showed excellent susceptibility in non-invasive pneumococcal diseases strains.Linezolid,levofloxacin and vancomycin showed 100.0%susceptibility in all pneumococcal isolates.Conclusions:Implementation of vaccines should be considered,especially for children and high-risk populations.This may contribute to reducing pneumococcal and meningococcal invasive disease burden and help prevent emergence of antimicrobial resistant strains.
文摘One of the new strategies for the prevention of HIV acquisition is the use of microbicides such as topical microbicides including antimicrobial and antiviral peptides. Ideally, new drug candidates should kill pathogens without determent to the normal bacterial flora considered important in health;such as hydrogen peroxide producing Lactobacillus species. The antimicrobial peptides LL-37 and LSA-5 were studied to determine their spectrum of activity against bacterial pathogens and normal flora organisms. The effects of divalent cations at biologically relevant concentrations were determined. We show the synthetic lytic peptide LSA-5 and the naturally occurring peptides LL-37 inactivate Neisseria gonorrhoeae but are less active against many normal flora members such as Lactobacillus species. Biologically relevant concentrations of calcium and magnesium prevented killing of sensitive strains. LSA-5 is more potent than LL-37, both are inhibited from killing sensitive strains by calcium and magnesium. Strains of Lactobacillus iners were killed by both microbicides even in the presence of the divalent cations. Antimicrobial peptides, such as LSA-5, have good potential for use in prevention of sexually transmitted disease, if formulated to sequester calcium and magnesium present in biological fluids.
文摘In this study, we investigate the potential for oral Lactobacilli (LB) to afford innate protection against nasopharyngeal coloniser Neisseria meningitidis serogroup B (NmB), which causes the bulk of UK meningococcal disease. Oral isolates of L. plantarum, L. salivarious, L. casei, L. rhamnosus, L. gasseri and gut probiotic L. rhamnosus GG were assessed for their ability to suppress nasopharyngeal epithelial inflammatory responses to pathogenic NmB. The specificity of attenuation was examined using TLR 2 ligand, Pam3Cys, and early response cytokine IL1β;and the mechanism of attenuation was explored using heat-killed organisms and conditioned medium. Pro-inflammatory IL-6 and TNFα cytokine secretion was quantified by ELISA and associated cell death was quantified by PI staining and LDH release. NmB adhesion, invasion and metabolism were determined using standard gentamicin protection with viable counts, and bioluminescence, respectively. L. plantarum and L. salivarious suppressed IL-6 and TNFα secretions from NmB-infected epithelial cells. LB did not need to be alive and could suppress using secretions, which were independent of TLR2 or IL1β receptor signalling. L. plantarum, in particular, reduced NmB-induced necrotic cell death of epithelial monolayers. Like L. salivarious, it significantly inhibited NmB adhesion but uniquely L. plantarum abolished NmB invasion. Using bioluminescence as a reporter of pathogen metabolism, L. plantarum and its secretions were found to inhibit NmB metabolism during cell invasion assays. We conclude that oral L. plantarum and its secretions could be used to help reduce the burden of meningococcal disease by removing the intracellular nasopharyngeal reservoir of NmB.
文摘Chlamydial and gonococcal infections are recognized as two of the major causes of sexually transmissible human bacterial infection which may lead to infertility. In this cross sectional study, we aimed to determine the prevalence of Neisseria gonorrhoeae, Chlamydia trachomatis among Egyptian women using different microbiological methods. One hundred and fifty cervical swabs were collected, of which 100 were from infertile women. Culture and ELISA technique were used for screening of Neisseria gonorrhoeae and Chlamydia trachomatis individually. In addition, PCR was used for all examined samples. For C. trachomatis, 3 cases were positive for antigen detection by ELISA. Moreover, in obtained results of PCR, DNA was detected in 4 samples, and three of them from infertile group. So based on PCR results, the sensitivity and specificity of ELISA were 75% and 100% respectively. Furthermore, 3 samples were positive for gonococcal infections by PCR, and two of them were taken from infertile women. Positive results of two samples were verified by culture. The estimated sensitivity and specificity of culture method were 66.7% and 100% respectively. Results of this study indicate that PCR is a valuable method for detection of gonococcal and chlamydial infection and it is suitable for the confirmation of ELISA results for C. trachomatis diagnosis. Culture method is less sensitive than PCR for detection of N. gonorrhoeae. The prevalence of such infections is higher among infertile women.
文摘Neisseria meningitidis(N.meningitidis) is an exclusively human pathogen that has been identified in 10%-35% of the adult population and in 5.9% of the child population.Despite the high prevalence of carriers of N.meningitidis,it only occasionally causes meningococcal disease in the context of endemic disease,in certain geographic areas or in isolated epidemic outbreaks.After the N.meningitidis genome is described,progress has been made toward understanding the pathogenic mechanisms of the bacteria,although some aspects concerning its interaction with the environment and the host remain unclear.Some studies have reported that oxidative stress in the environment can modify the surface characteristics of N.meningitidis,increasing its adhesive properties and favouring an asymptomaticcarrier state.The antigenic structure of N.meningitidis can be modified by its importing genetic material from other bacteria in its ecological niche.Some structures of lipopolysaccharides help it to evade the immune response,and these are observed more frequently in N.meningitidis isolated from blood than in healthy nasopharyngeal carriers.There is evidence that pili and capsule are downregulated upon contact with target cells.This paper reviews current knowledge on hostenvironment-bacteria mechanisms and interactions,with the aim of contributing to our understanding of the pathogenic mechanisms of N.meningitidis.
文摘Background:Neisseria gonorrhoeae is a gram-negative diplococcus that leads to sexually transmitted infection.N.gonorrhoeae is an obligate human pathogen that causes infection to the mucus-secreting epithelial cells both in males and females.In 2017 the center for disease control and the World Health Organization published the list of global priority pathogens-12 with denting therapeutic options,including antibiotic-resistant N.gonorrhoeae.Methods:we thoroughly characterized zoliflodacin antibiotic,its clinical trials and effect on human health by using different keywords like“zoliflodacin”,“COVID-19”,“clinical trials”from different data sources like Pub-Med,Google-Scholar,and Science-Direct.Results:Zoliflodacin shows a therapeutic approach against N.gonorrhoeae.It acts by inhibiting bacterial type 2 topoisomerase with the binding sites in bacterial gyrase.It shows promising results against N.gonorrhoeae.Zoliflodacin is effective in treating gonococcal urogenital and rectal infection.Conclusion:Currently,antibiotic is the only option to treat N.gonorrhoeae with no vaccine available to treat it.The new drug,zoliflodacin,specifically targets antibiotic-resistant gonorrhea and it has given a hope to researchers.This review elaborates the discovery of zoliflodacin,its mechanism of action,current clinical trials,and its effectiveness.
基金the National Natural Science Foundation of China (No. 30700717 and No. 30371293)New Teacher Foundation of Ministry of Education of China (No. 20070487140)
文摘To identify the genomic species of Neisseria gonorrhoeae, evaluate the difference between two molecular epidemiological methods and examine the relationship between sex partners and genotypes of bacteria, 24 strains of Neisseria gonorrhoeae isolated from the outpatients with gonorrhea were identified by using the Opa genotyping and NG-MAST genotyping and the relationship between genotypes and phenotypes was studied. Twenty-four strains of Neisseria gonorrhoeae fell into 10 ST genotypes by NG-MAST genotyping, whereas these strains were classified into 12 OT Opa genotypes by Opa genotyping. A new epidemic strain of ST genotype (217-86% homologisation 178) in China was identified. It is concluded that genotypes of each pair of strains from a pair of patient/sex partner besides 45/46 are the same, indicating that contagious infection take place between patient and the sex partner. Opa genotyping was more effective than NG-MAST genotyping in identifying the genomic species of Neisseria gonorrhoeae. ST genotype could be further classified into different Opa-types.
文摘In order to study the resistance of Neisseria (N.) gonorrhoeae to the fluoroquinolone and detect mutation patterns of quinolone resistance-determining regions (QRDRs) of clinical isolates in Shanghai, China, a total of 80 clinical isolates of N. gonorrhoeae were consecutively collected from Shanghai. The MIC of fluoroquinolone for the isolates was examined by using the agar dilution method and the mutation profiles of the QRDRs of gyrA and parC were analyzed by sequencing and restriction fragment length polymorphism (RFLP). Chi-square test was used for comparison of the mutation patterns. The results showed that: (1) High percentages of the 8 isolates were resistant to ciprofloxacin (95.0%), ofloxacin (95.0%) and lomefloxacin (97.5%), only one strain was susceptible to the ciprofloxacin. (2) Sensitive strains had a substitute of Asp95→Ala in the gyrA, and all isolates that were resistant or intermediated to the ciprofloxacin, had a double mutation in the gyrA (Ser91, Ala 92 and Asp95). Some strains also had a mutation in the parC. (3) The MICs of these isolates were significantly associated with the mutation patterns in the gyrA and parC. A double mutation of gyrA combined with parC87 mutation was a predominant pattern in Shanghai and could mediate high level resistance to ciprofloxacin. It suggests that mutations in the QRDRs of gyrA and parC may be re-sponsible for the fluoroquinolone resistance. And fluoroquinolone could not be used as the first line antibiotics for gonorrhea treatment any more in Shanghai, China.
基金This project was supported by a grant from the NationalNatural Science Foundation of China (No .30371293)
文摘To study the relationship between mutation of the inverted repeat sequence (IR) in the multiple transferable resistant system (mtr) of Neisseria gonorrhoeae (NG) and its multiple antibiotic resistance, minimal inhibitory concentrations (MICs) for the clinically isolated strains were tested by agar-dilution-method. The mtr system’s IR gene of NG was sequenced after amplification by polymerase chain reaction (PCR). Either two susceptive or five penicillin-resistant strains had no base mutation in IR gene, while all of the 13 strains with multiple-antibiotic-resistance had a single-base deletion (A/T). The result suggests that a single-base deletion of the thirteen-base IR sequence in mtr system of NG might result in multiple antibiotic resistance but is not associated with single antibiotic resistance.
基金supported by a grant (the Key Technologies R&D Program 2005BA711A09) from the Ministry of Science and Technology, of China
文摘Objective During 2003-2005, an outbreak of meningitis due to Neisseria meningitidis serogroup C occurred in China. With the aim to find strain clues result in the final epidemics, the ancestral strain 053442, a clinical isolate, and a carrier strain 053426 with different gene type were analyzed. Methods Clinical strain 053442 and carrier strain 053426 were cultured on GC agar plates under the same condition. Two-dimensional electrophoresis was performed using the pH 3-10 nonlinear IPG strips of 24 cm length, and all the protein spots were identified by matrix-assisted laser desorption/ionization time of flight spectrometry. Results 502 and 380 protein spots were identified in 053426 and 053442 respectively, relating to 266 and 202 different genes covering a wide range of cellular functions. The express volume and number of proteins involved in energy metabolism, protein synthesis and amino acid biosynthesis in 053426 were higher than in 053442. Virulence factor Opa, Opc and a series of proteins involved in pilus assembly and retraction were identified in 053442, which appear to be of primary importance in colonization and invasion of human cells. Compared to 053442, virulence protein species were less in 053426, with lower express volumes too. No Opa and Opc were detected in 053426. Conclusion The different protein expression profiles of the clinical strain 053442 and carrier strain 053426 in the present study provide some clues of the different pathogenicity of the two strains, which may account for result in the final epidemics.
文摘In order to provide a rational research basis for detection of resistance of Neisseria gonorrhoeae to antimicrobial hydrophobic agents and study on the resistant mechanism of multiple transferable resistance (mtr) efflux system, plasmid pET-28a(+) encoding mtrC gene was constructed and the related target protein was expressed in Escherichia coli(E.coli) DE3. The fragments of mtrC gene of Neisseria gonorrhoeae from the standard strains were amplified and cloned into prokaryotic expression plasmid pET-28a(+) with restriction endonuclease to construct recombinant pET-mtrC which was verified by restriction endonuclease and DNA sequencing. The recombinant was transformed into E.coli DE3 to express the protein mtrC induced by IPTG. The results showed mtrC DNA fragment was proved correct through restriction endonuclease and DNA sequencing. Its sequence was 99.5 % homologus to that published on GeneBank (U14993). A 48.5 kD fusion protein which was induced by IPTG was detected by SDS-PAGE. It was concluded that the construction of prokaryotic expression plasmid of mtrC protein of Neisseria gonorrhoeae was correct and the fusion protein was successively expressed in E.coli.
文摘Objective: To investigate the serotypes and auxotypes distribution of Neisseria gonorrhoeae in Guangzhou. Method: 131 strains of Neisseria gonorrhoeae were serotyped by co-agglutination test and 108 strains were auxotyped by La Scolea's method. Results: Out of 131 strains of Neisseria gonorrhoeae ,87.8% (115/131) were WⅡ/WⅢ, while 9.9% (131131) were WI. The most important auxotypes were Proto, Pro and ILe,42.6% (46/108), 21.3% (23/108) and 12.0%, respectively. WII/WIII was distributed among the all auxotypes aboveand WⅠ found only in both Proto and Pro. Conclusion: The study illustrated the prevailing serotype,WⅡ/WⅢ, and higher prevalence of Ile- in Guangzhou.