scholarly journals Antimicrobial susceptibility, auxotype and plasmid content of Neisseria gonorrhoeae in northern Tanzania: emergence of high level plasmid mediated tetracycline resistance.

1995 ◽  
Vol 71 (1) ◽  
pp. 9-12
Author(s):  
B West ◽  
J Changalucha ◽  
H Grosskurth ◽  
P Mayaud ◽  
R M Gabone ◽  
...  
Antibiotics ◽  
2018 ◽  
Vol 7 (3) ◽  
pp. 77 ◽  
Author(s):  
Johan Melendez ◽  
Justin Hardick ◽  
Mathilda Barnes ◽  
Kathleen Page ◽  
Charlotte Gaydos

The increasing rates of gonorrhea infections and the global emergence and spread of multi-drug-resistant Neisseria gonorrhoeae (NG) threaten the successful management of gonorrhea. In the era of nucleic acid amplification tests (NAATs), surveillance projects are urgently needed to monitor prevalence and trends in the antimicrobial susceptibility of NG. In this study, we retrospectively determined the susceptibility profile of NG isolates to previously and currently prescribed antimicrobials. NG isolates collected in Baltimore, Maryland between January and October 2016 were evaluated by the E-test method and/or molecular methods for susceptibility to ceftriaxone, azithromycin, ciprofloxacin, tetracycline, gentamicin, and penicillin. One-hundred and forty-three NG isolates from African-American males (98.6%), primarily heterosexual (88.8%), ranging in age from 15 to 69 years of age were included in the study. Ciprofloxacin resistance was observed in 44.1% of isolates. Plasmid-mediated resistance to penicillin and tetracycline resistance was detected in 22.4% and 10.1% of isolates, respectively. Three isolates (2.1%) displayed high-level resistance to azithromycin (minimum inhibitory concentration (MIC) > 256 μg/mL). Forty-three percent of isolates were resistant or had decreased susceptibility to three antimicrobials (ciprofloxacin, tetracycline, and penicillin). All isolates were susceptible to ceftriaxone and gentamicin. Overall, the epidemiology of antimicrobial resistant NG in Baltimore continues to evolve, and the emergence of azithromycin resistance in this population emphasizes the need for continued sentinel surveillance programs to monitor susceptibility trends and aid in treatment recommendations.


1990 ◽  
Vol 1 (4) ◽  
pp. 136-138
Author(s):  
Vivian G Loo ◽  
Andrew E Simor ◽  
Ruth Jaeger ◽  
Donald E Low

The minimal inhibitory concentrations (MICs) of penicillin, tetracycline, erythromycin, cefoxitin, ceftriaxone and spectinomycin were determined for 300 consecutive strains ofNeisseria gonorrhoeaecollected from physicians’ offices in Ontario. Only four isolates were found to produce beta-lactamase. Of the remaining 296 isolates, five (1.7%) had penicillin MICs greater than or equal to 1 mg/L, 78 (26.3%) had tetracycline MICs greater than or equal to 1 mg/L, 13 (4.4%) had cefoxitin MICs greater than or equal to 1 mg/L and 43 (14.5%) had erythromycin MICs greater than or equal to 1 mg/L. Two isolates (0.7%) had high level tetracycline resistance with MICs greater than or equal to 16 mg/L. AllN gonorrhoeaeisolates were susceptible to ceftriaxone and to spectinomycin.


2005 ◽  
Vol 49 (10) ◽  
pp. 4327-4334 ◽  
Author(s):  
Mei Hu ◽  
Sobhan Nandi ◽  
Christopher Davies ◽  
Robert A. Nicholas

ABSTRACT Neisseria gonorrhoeae becomes resistant to tetracycline by two major mechanisms: expression of a plasmid-encoded TetM protein and mutations in endogenous genes (chromosomally mediated resistance). Early studies by Sparling and colleagues (P. F. Sparling F. A. J. Sarubbi, and E. Blackman, J. Bacteriol. 124:740-749, 1975) demonstrated that three genes were involved in high-level chromosomally mediated tetracycline resistance (MIC of tetracycline ≥ 2 μg/ml): ery-2 (now referred to as mtrR), penB, and tet-2. While the identities of the first two genes are known, the tet-2 gene has not been identified. We cloned the tet-2 gene, which confers tetracycline resistance, from tetracycline-resistant clinical isolate N. gonorrhoeae FA6140 and show that resistance is due to a single point mutation (Val-57 to Met) in the rpsJ gene (rpsJ1) encoding ribosomal protein S10. Moreover, the identical mutation was found in six distinct tetracycline-resistant clinical isolates in which the MIC of tetracycline was ≥2 μg/ml. Site-saturation mutagenesis of the codon for Val-57 identified two other amino acids (Leu and Gln) that conferred identical levels of resistance as the Met-57 mutation. The mutation maps to the vertex of a loop in S10 that is near the aminoacyl-tRNA site in the structure of the 30S ribosomal subunit from Thermus thermophilus, and the residue equivalent to Val-57 in T. thermophilus S10, Lys-55, is within 8 to 9 Å of bound tetracycline. These data suggest that large noncharged amino acids alter the rRNA structure near the tetracycline-binding site, leading to a lower affinity of the antibiotic.


1999 ◽  
Vol 10 (10) ◽  
pp. 646-651 ◽  
Author(s):  
T Beattie ◽  
A Moyes ◽  
C Patrizio ◽  
H Young

Tetracycline resistant Neisseria gonorrhoeae (TRNG) contain a 25.2 MDa TetM plasmid encoding a 68KDa cytoplasmic protein which confers high-level tetracycline resistance. The aim of this study was to subtype all TRNG isolated in Scotland between 1992 and 1998. Subtyping was performed by a polymerase chain reaction (PCR) assay which characterizes the TetM plasmid as either the Dutch variant (443 base pair product) or the American variant (777 base pair product). Of the 78 TRNG isolates, 35 were the American variant and 43 were the Dutch variant. TRNG were distributed amongst 30 serovar/auxotype classes, the most common being 1A6/NR (11.5%), 1A6/P (14.1%) and 1B4/NR (14.1%). The country where infection was acquired was known for 36 of the 46 TRNG strains isolated between 1996 and 1998. All infections acquired in Asia and South America were the Dutch variant whereas all infections acquired in Africa were the American variant. A penicillinase plasmid was present in 66% (23/35) of the American variant TRNG compared with 51% (22/43) of the Dutch variant: the 3.2 MDa penicillinase plasmid was found in 87% of the American variant TRNG whereas the 4.4 MDa penicillinase plasmid was found in 68% of the Dutch variant TRNG. We conclude that subtyping of TRNG by PCR is a useful tool in studying the epidemiology of gonococcal infection due to plasmid-mediated resistant isolates.


2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Mary Wandia Kivata ◽  
Margaret Mbuchi ◽  
Fredrick Eyase ◽  
Wallace Dimbuson Bulimo ◽  
Cecilia Katunge Kyanya ◽  
...  

Abstract Background Treatment of gonorrhea is complicated by the development of antimicrobial resistance in Neisseria gonorrhoeae (GC) to the antibiotics recommended for treatment. Knowledge on types of plasmids and the antibiotic resistance genes they harbor is useful in monitoring the emergence and spread of bacterial antibiotic resistance. In Kenya, studies on gonococcal antimicrobial resistance are few and data on plasmid mediated drug resistance is limited. The present study characterizes plasmid mediated resistance in N. gonorrhoeae isolates recovered from Kenya between 2013 and 2018. Methods DNA was extracted from 36 sub-cultured GC isolates exhibiting varying drug resistance profiles. Whole genome sequencing was done on Illumina MiSeq platform and reads assembled de-novo using CLC Genomics Workbench. Genome annotation was performed using Rapid Annotation Subsystem Technology. Comparisons in identified antimicrobial resistance determinants were done using Bioedit sequence alignment editor. Results Twenty-four (66.7%) isolates had both β-lactamase (TEM) and TetM encoding plasmids. 8.3% of the isolates lacked both TEM and TetM plasmids and had intermediate to susceptible penicillin and tetracycline MICs. Twenty-six (72%) isolates harbored TEM encoding plasmids. 25 of the TEM plasmids were of African type while one was an Asian type. Of the 36 isolates, 31 (86.1%) had TetM encoding plasmids, 30 of which harbored American TetM, whereas 1 carried a Dutch TetM. All analyzed isolates had non-mosaic penA alleles. All the isolates expressing TetM were tetracycline resistant (MIC> 1 mg/L) and had increased doxycycline MICs (up to 96 mg/L). All the isolates had S10 ribosomal protein V57M amino acid substitution associated with tetracycline resistance. No relation was observed between PenB and MtrR alterations and penicillin and tetracycline MICs. Conclusion High-level gonococcal penicillin and tetracycline resistance in the sampled Kenyan regions was found to be mediated by plasmid borne blaTEM and tetM genes. While the African TEM plasmid, TEM1 and American TetM are the dominant genotypes, Asian TEM plasmid, a new TEM239 and Dutch TetM have emerged in the regions.


1990 ◽  
Vol 36 (1) ◽  
pp. 64-67 ◽  
Author(s):  
Jo-Anne R. Dillon ◽  
Maria Carballo

Between October 1987 and June 1989, 84 isolates of Neisseria gonorrhoeae carrying the TetM resistance determinant (TRNG) were received at the Laboratory Centre for Disease Control, Ottawa, from six Canadian provinces and were characterized into classes based on auxotype, serovar and plasmid content. One-fifth (17/84) of the TRNG were also penicillinase producing (PPNG). The PPNG–TRNG isolates comprised six classes based on auxotype, serovar, and plasmid content. Most (16/17) PPNG–TRNG carried 3.2-MDa β-lactamase plasmids and the 25.2-MDa TetM-containing plasmid. We report, for the first time, the association of a 4.5-MDa β-lactamase plasmid with the 25.2-MDa plasmid in a clinical TRNG isolate. Non-PPNG TRNG isolates comprised 11 classes based on auxotype, serovar, and plasmid content, including two previously unreported auxotype–serovar classes, P/IB-26 and P/IB-20. Key words: Neisseria gonorrhoeae, tetracycline resistance, plasmid, epidemiology.


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