Rapid Emergence of High-Level Resistance to Quinolones in Campylobacter jejuni Associated with Mutational Changes in gyrA and parC

ABSTRACT Quinolone resistance in clinical isolates of Campylobacter jejuni in Sweden increased more than 20-fold at the beginning of the 1990s. Resistance to 125 μg of ciprofloxacin per ml in clinical isolates was associated with chromosomal mutations in C. jejuni leading to a Thr-86-Ile substitution in thegyrA product and a Arg-139-Gln substitution in theparC product.

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Susceptibility trends of zoliflodacin against multidrug-resistant Neisseria gonorrhoeae clinical isolates in Nanjing, China (2014-2018)

10.1101/2020.05.04.078055 ◽

2020 ◽

Author(s):

Wenjing Le ◽

Xiaohong Su ◽

Xiangdi Lou ◽

Xuechun Li ◽

Xiangdong Gong ◽

...

Keyword(s):

Neisseria Gonorrhoeae ◽

Dna Sequencing ◽

Multidrug Resistant ◽

Quinolone Resistance ◽

Clinical Isolates ◽

Drug Resistant ◽

Extended Spectrum ◽

High Level ◽

Level Resistance

ABSTRACTPreviously, we reported potent activity of a novel spiropyrimidinetrione, zoliflodacin, against N. gonorrhoeae isolates from symptomatic men in Nanjing, China, collected in 2013. Here, we investigated trends of susceptibilities of zoliflodacin in 986 gonococcal isolates collected from men between 2014 and 2018. N. gonorrhoeae isolates were tested for susceptibility to zoliflodacin and seven other antibiotics. Mutations in gyrA, gyrB, parC and parE genes were determined by PCR and DNA sequencing. The MIC of zoliflodacin for N. gonorrhoeae ranged from ≤0.002 to 0.25 mg/L; the overall MIC50s and MIC90s were 0.06 mg/L and 0.125mg/L in 2018, increasing two-fold from 2014. However, the percent of isolates with lower zoliflodacin MICs declined in each year sequentially while the percent with higher MICs increased yearly (P≤0.00001). All isolates were susceptible to spectinomycin but resistant to ciprofloxacin (MIC ≥1 μg/ml); 21.2% (209/986) were resistant to azithromycin (≥1 μg/ml), 43.4% (428/986) were penicillinase-producing (PPNG), 26.9% (265/986) tetracycline-resistant (TRNG) and 19.4% (191/986) were multi-drug resistant (MDR) isolates. Among 143 isolates with higher zoliflodacin MICs (0.125-0.25 mg/L), all had quinolone resistance associated double or triple mutations in gyrA; 139/143 (97.2%) also had mutations in parC. There were no D429N/A and/or K450T mutations in GyrB identified in the 143 isolates with higher zoliflodacin MICs; a S467N mutation in GyrB was identified in one isolate. We report that zoliflodacin has excellent in vitro activity against clinical gonococcal isolates, including those with high-level resistance to ciprofloxacin, azithromycin and extended spectrum cephalosporins.

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High-Level Quinolone Resistance in Clinical Isolates of Campylobacter jejuni

The Journal of Infectious Diseases ◽

10.1093/infdis/165.4.667 ◽

1992 ◽

Vol 165 (4) ◽

pp. 667-670 ◽

Cited By ~ 66

Author(s):

J. Segreti ◽

T. D. Gootz ◽

L. J. Goodman ◽

G. W. Parkhurst ◽

J. P. Quinn ◽

...

Keyword(s):

Campylobacter Jejuni ◽

Quinolone Resistance ◽

Clinical Isolates ◽

High Level

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High-Level Resistance to Trimethoprim in Clinical Isolates of Campylobacter jejuni by Acquisition of Foreign Genes (dfr1 and dfr9) Expressing Drug-Insensitive Dihydrofolate Reductases

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.42.12.3059 ◽

1998 ◽

Vol 42 (12) ◽

pp. 3059-3064 ◽

Cited By ~ 40

Author(s):

Amera Gibreel ◽

Ola Sköld

Keyword(s):

Campylobacter Jejuni ◽

Resistance Genes ◽

The Other ◽

Clinical Isolates ◽

Resistance Level ◽

Dihydrofolate Reductases ◽

Foreign Genes ◽

The Right ◽

High Level ◽

Level Resistance

ABSTRACT The pathogenic bacterium Campylobacter jejuni has been regarded as endogenously resistant to trimethoprim. The genetic basis of this resistance was characterized in two collections of clinical isolates of C. jejuni obtained from two different parts of Sweden. The majority of these isolates were found to carry foreigndfr genes coding for resistant variants of the dihydrofolate reductase enzyme, the target of trimethoprim. The resistance genes, found on the chromosome, were dfr1 anddfr9. In about 10% of the strains, the dfr1and dfr9 genes occurred simultaneously. About 10% of the examined isolates were found to be negative for these dfrgenes and showed a markedly lower trimethoprim resistance level than the other isolates. The dfr9 and dfr1 genes were located in the context of remnants of a transposon and an integron, respectively. Two different surroundings for thedfr9 gene were characterized. One was identical to the right-hand end of the transposon Tn5393, and in the other, the dfr9 gene was flanked by only a few nucleotides of a Tn5393 sequence. The insertion of the dfr9 gene into the C. jejuni chromosome could have been mediated by Tn5393. The frequent occurrence of high-level trimethoprim resistance in clinical isolates of C. jejuni could be related to the heavy exposure of food animals to antibacterial drugs, which could lead to the acquisition of foreign resistance genes in naturally transformable strains of C. jejuni.

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Sequence of quinolone resistance-determining region of gyrA gene for clinical isolates and for an in vitro-selected quinolone-resistant strain of Coxiella burnetii.

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.40.4.870 ◽

1996 ◽

Vol 40 (4) ◽

pp. 870-873 ◽

Cited By ~ 21

Author(s):

D Musso ◽

M Drancourt ◽

S Osscini ◽

D Raoult

Keyword(s):

Amino Acid ◽

Coxiella Burnetii ◽

Resistant Strain ◽

Quinolone Resistance ◽

Clinical Isolates ◽

Low Level ◽

Nucleotide Mutation ◽

High Level ◽

Level Resistance

We report the sequence of the quinolone resistance-determining region of the gyrA genes of either susceptible or low-level-resistant clinical isolates of Coxiella burnetii. The sequences of low-level (MICs, 4 micrograms/ml) and high-level (MICs, 8 and 16 micrograms/ml) resistant strains stepwise selected in vitro were also determined. The gene sequences of all of the clinical isolates and that of the in vitro-selected low-level-resistant strain were identical. Sequence analysis of the in vitro-selected high-level-resistant strain revealed a nucleotide mutation leading to an amino acid substitution of Gly in place of Glu at position 87 of the GyrA amino acid sequence. These results indicate that high-level resistance to ciprofloxacin is associated with a nucleotide mutation in gyrA, whereas low-level resistance to quinolones is not.

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Significant contribution of the CmeABC Efflux pump in high-level resistance to ciprofloxacin and tetracycline in Campylobacter jejuni and Campylobacter coli clinical isolates

Annals of Clinical Microbiology and Antimicrobials ◽

10.1186/s12941-021-00439-6 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Saeed Sharifi ◽

Bita Bakhshi ◽

Shahin Najar-peerayeh

Keyword(s):

Gene Expression ◽

Point Mutation ◽

Campylobacter Jejuni ◽

Significant Contribution ◽

Efflux Pump ◽

Campylobacter Coli ◽

Rapd Pcr ◽

Resistant Strains ◽

High Level ◽

Level Resistance

Abstract Background Campylobacter resistance to antimicrobial agents is regarded as a major concern worldwide. The aim of this study was to investigate the expression of the CmeABC efflux pump and the RAPD-PCR pattern in drug-resistant Campylobacter isolates. Methods A total of 283 stool specimens were collected from children under the age of five with diarrhea. The minimum inhibitory concentration (MIC) of tetracycline and ciprofloxacin was determined by broth microdilution method and E-test, respectively. Detection of tetracycline and ciprofloxacin determinants was done by amplification of tetO gene and PCR-sequencing of the gyrA gene. The cmeABC transcriptional expression was analyzed by Real-time (RT)-PCR. Clonal correlation of resistant strains was determined by RAPD-PCR genotyping. Results Out of 283 fecal samples, 20 (7.02%) samples were positive for Campylobacter spp. Analysis of duplex PCR assay of the cadF gene showed that 737 and 461 bp amplicons were corresponding to Campylobacter jejuni and Campylobacter coli, respectively. All of the 17 phenotypically tetracycline-resistant Campylobacter isolates harbored the tetO gene. Also, four phenotypically ciprofloxacin-resistant Campylobacter isolates had a point mutation at codon 257 of the gyrA gene (ACA to ATA; Thr > Ile). High-level expression of the cmeA gene was observed in ciprofloxacin-resistant and high-level tetracycline-resistant Campylobacter isolates, suggesting a positive correlation between the cmeA gene expression level and tetracycline resistance level. Moreover, a statistically significant difference was observed in the cmeA gene expression between ciprofloxacin-resistant and ciprofloxacin-susceptible strains, which signifies the crucial contribution of the efflux pump in conferring multiple drug resistance phenotype among Campylobacter spp. RAPD analysis of Campylobacter isolates exhibited 16 different patterns. Simpsone`s diversity index of RAPD-PCR was calculated as 0.85, showing a high level of homogeneity among the population; however, no clear correlation was detected among tetracycline and/or ciprofloxacin resistant isolates. Conclusion Significant contribution of the CmeABC efflux pump in conferring high-level resistance to tetracycline and ciprofloxacin was observed in C. jejuni and C. coli clinical isolates. The resistant phenotype is suggested to be mediated by CmeABC efflux pumps, the tetO gene, and point mutation of the gyrA gene. Genotyping revealed no clonal correlation among resistant strains, indicating distinct evolution of tetracycline and ciprofloxacin resistant genotypes among the isolates.

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Molecular aspects of high-level resistance to sulbactam-cefoperazone in Klebsiella oxytoca clinical isolates.

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.40.9.1988 ◽

1996 ◽

Vol 40 (9) ◽

pp. 1988-1994 ◽

Cited By ~ 7

Author(s):

K Kimura ◽

Y Arakawa ◽

S Ohsuka ◽

H Ito ◽

K Suzuki ◽

...

Keyword(s):

Klebsiella Oxytoca ◽

Polyacrylamide Gel Electrophoresis ◽

Sodium Dodecyl ◽

Point Of View ◽

Clinical Isolates ◽

Beta Lactamase ◽

Beta Lactamases ◽

Molecular Aspects ◽

High Level ◽

Level Resistance

Nine Klebsiella oxytoca strains which demonstrated resistance to the combination of sulbactam and cefoperazone were isolated from geographically separate hospitals in Japan in 1995. Among them, K. oxytoca SB23 showed high-level resistance to sulbactam-cefoperazone (MIC > 128 micrograms/ml) and aztreonam (MIC, 128 micrograms/ml). The sulbactam-cefoperazone resistance was not transferred from strain SB23 to Escherichia coli CSH2 by conjugation, beta-Lactamase RbiA, produced by strain SB23, was purified, and the molecular mass was estimated to be 29 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Kinetic parameters for RbiA revealed that cefoperazone and aztreonam were hydrolyzed efficiently by this enzyme. Moreover, ceftazidime and imipenem were also hydrolyzed weakly by RbiA, although strain SB23 did not show any resistance to these agents. Clavulanate, sulbactam, and tazobactam failed to block the hydrolysis of cefoperazone by RbiA. The structural gene of RbiA (blaRBI) was cloned and sequenced, and the deduced amino acid sequence of RbiA demonstrated high-level similarities to those of the beta-lactamases found in K. oxytoca D488, E23004, and plasmid-mediated MEN-1, which have been classified into Bush functional group 2be. Although RbiA demonstrates high-level molecular similarity to the enzymes in group 2be, from an enzymological point of view, this enzyme might be differentiated from the enzymes in that group. Hybridization analysis revealed that beta-lactamase genes highly similar to blaRBI were generally encoded on the chromosome of the sulbactam-cefoperazone-resistant clinical isolates of K. oxytoca tested in the study, despite their different derivations. This observation suggests that sulbactam-cefoperazone-resistant A. oxytoca strains which produce RbiA-type beta-lactamases have been proliferating in many hospitals in Japan.

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High-level resistance to gentamicin in clinical isolates of Streptococcus (Enterococcus) faecium.

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.32.10.1528 ◽

1988 ◽

Vol 32 (10) ◽

pp. 1528-1532 ◽

Cited By ~ 53

Author(s):

G M Eliopoulos ◽

C Wennersten ◽

S Zighelboim-Daum ◽

E Reiszner ◽

D Goldmann ◽

...

Keyword(s):

Enterococcus Faecium ◽

Clinical Isolates ◽

High Level ◽

Level Resistance

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Genetic Basis of Multidrug Resistance in Acinetobacter baumannii Clinical Isolates at a Tertiary Medical Center in Pennsylvania

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00570-08 ◽

2008 ◽

Vol 52 (11) ◽

pp. 3837-3843 ◽

Cited By ~ 95

Author(s):

Jennifer M. Adams-Haduch ◽

David L. Paterson ◽

Hanna E. Sidjabat ◽

Anthony W. Pasculle ◽

Brian A. Potoski ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Genetic Basis ◽

Medical Center ◽

Multidrug Resistant ◽

Quinolone Resistance ◽

Clinical Isolates ◽

Clinical Microbiology Laboratory ◽

Carbapenemase Gene ◽

Methylase Gene ◽

High Level

ABSTRACT A total of 49 unique clinical isolates of multidrug-resistant (MDR) Acinetobacter baumannii identified at a tertiary medical center in Pittsburgh, Pennsylvania, between August 2006 and September 2007 were studied for the genetic basis of their MDR phenotype. Approximately half of all A. baumannii clinical isolates identified during this period qualified as MDR, defined by nonsusceptibility to three or more of the antimicrobials routinely tested in the clinical microbiology laboratory. Among the MDR isolates, 18.4% were resistant to imipenem. The frequencies of resistance to amikacin and ciprofloxacin were high at 36.7% and 95.9%, respectively. None of the isolates was resistant to colistin or tigecycline. The presence of the carbapenemase gene bla OXA-23 and the 16S rRNA methylase gene armA predicted high-level resistance to imipenem and amikacin, respectively. bla OXA-23 was preceded by insertion sequence ISAba1, which likely provided a potent promoter activity for the expression of the carbapenemase gene. The structure of the transposon defined by ISAba1 differed from those reported in Europe, suggesting that ISAba1-mediated acquisition of bla OXA-23 may occur as an independent event. Typical substitutions in the quinolone resistance-determining regions of the gyrA and parC genes were observed in the ciprofloxacin-resistant isolates. Plasmid-mediated quinolone resistance genes, including the qnr genes, were not identified. Fifty-nine percent of the MDR isolates belonged to a single clonal group over the course of the study period, as demonstrated by pulsed-field gel electrophoresis.

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