Prevalence of
 qnr
 ,
 aac(6
 ′
 )-Ib-cr
 ,
 qepA
 , and
 oqxAB
 in Escherichia coli Isolates from Humans, Animals, and the Environment

Chen, Xiang; Zhang, Weiqiu; Pan, Weijuan; Yin, Jiajun; Pan, Zhiming; Gao, Song; Jiao, Xinan

doi:10.1128/aac.06191-11

Cited by 165 publications

(89 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The widespread use of these compounds may exert selection pressure for the rapid emergence of oqxAB in swine and poultry isolates. These chemical compounds are seldom used in cattle (13). Humans may be exposed to these resistant bacteria through visits to farms, wet markets, and contacts with contaminated meats (17,38).…”

Section: Discussionmentioning

confidence: 99%

“…Previously reported primers were used to detect oqxA and oqxB (13). PCR mapping was used to detect the presence of IS26 elements on the two sides of oqxAB (see Table S2 in the supplemental material).…”

Section: Methodsmentioning

confidence: 99%

“…without the IS26 elements (11,12). The high prevalence of oqxAB has been reported among E. coli and Salmonella isolates of animal or meat origins in China (13)(14)(15)(16)(17). In the current study, we investigated the association of plasmid-mediated oqxAB and nitrofurantoin resistance in E. coli isolates originating from human and animal sources.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Plasmid-Mediated OqxAB Is an Important Mechanism for Nitrofurantoin Resistance in Escherichia coli

et al. 2016

Antimicrob Agents Chemother

View full text Add to dashboard Cite

Increasing consumption of nitrofurantoin (NIT) for treatment of acute uncomplicated urinary tract infections (UTI) highlights the need to monitor emerging NIT resistance mechanisms. This study investigated the molecular epidemiology of the multidrugresistant efflux gene oqxAB and its contribution to nitrofurantoin resistance by using Escherichia coli isolates originating from patients with UTI (n ‫؍‬ 205; collected in 2004 to 2013) and food-producing animals (n ‫؍‬ 136; collected in 2012 to 2013) in Hong Kong. The oqxAB gene was highly prevalent among NIT-intermediate (11.5% to 45.5%) and -resistant (39.2% to 65.5%) isolates but rare (0% to 1.7%) among NIT-susceptible (NIT-S) isolates. In our isolates, the oqxAB gene was associated with IS26 and was carried by plasmids of diverse replicon types. Multilocus sequence typing revealed that the clones of oqxAB-positive E. coli were diverse. The combination of oqxAB and nfsA mutations was found to be sufficient for high-level NIT resistance. Curing of oqxAB-carrying plasmids from 20 NIT-intermediate/resistant UTI isolates markedly reduced the geometric mean MIC of NIT from 168.9 g/ml to 34.3 g/ml. In the plasmid-cured variants, 20% (1/5) of isolates with nfsA mutations were NIT-S, while 80% (12/15) of isolates without nfsA mutations were NIT-S (P ‫؍‬ 0.015). The presence of plasmid-based oqxAB increased the mutation prevention concentration of NIT from 128 g/ml to 256 g/ml and facilitated the development of clinically important levels of nitrofurantoin resistance. In conclusion, plasmid-mediated oqxAB is an important nitrofurantoin resistance mechanism. There is a great need to monitor the dissemination of this transferable multidrug-resistant efflux pump.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Plasmid-Mediated OqxAB Is an Important Mechanism for Nitrofurantoin Resistance in Escherichia coli

et al. 2016

Antimicrob Agents Chemother

View full text Add to dashboard Cite

show abstract

“…19 Since then PMQR genes have been described in several bacterial isolates particularly members of the Enterobacteriaceae family worldwide. 13,15,20,21,22 The qnr genes are known to produce proteins (QNR proteins) that protect the quinolone targets from inhibition. Studies have shown that they produce a low level resistance, but facilitate a higher level resistance in association with chromosomal mutations in bacteria harbouring them.…”

Section: Introductionmentioning

confidence: 99%

Molecular screening of antibiotic-resistant determinants among multidrug-resistant clinical isolates of Proteus mirabilis from SouthWest Nigeria

et al. 2017

View full text Add to dashboard Cite

Background: Globally, and particularly in developing countries, the menace of anti-microbial resistance is an accelerating problem. In Nigeria, increase in bacterial resistance has been phenotypically established but due to high cost, few molecular studies have been reported. Objectives: This study screened for presence of transferable resistance genes and mobile genetic elements (MGEs) such as integron among multi-drug resistant (MDR) P. mirabilis. Methods: A total of 108 P. mirabilis strains collected from five tertiary hospitals in SouthWest Nigeria were subjected to antibiotic susceptibility study using disc-diffusion method. Transferable resistance genes and MGEs were amplified using Polymerase chain reaction (PCR) analysis and amplicons sequenced. Results: Varied resistance was observed against all the antibiotics tested. About 56% of the isolates were MDR including those from 0-12 years old children. PCR analysis revealed the presence of aac(6')-Ib (33.3%), plasmid mediated quinolone resistance (PMQR) genes [qnrA (36.7%), acc(6')-Ib-cr (5%)], TEM (48.3%), CTX-M (6.7%) and integrons class 1 (58.3%) and class 2 (26.7%). Sequencing analysis revealed bla TEM-1 , bla CTX-M-15 associated with ISEcp1 and eight different arrays of gene cassettes: aadA1, aadA1-qacH, aadB-aadA2, aadA5, dfrA7, dfrA15, dfrA17, dfrA17-aadA5. Conclusion: Transferable resistance genes in association with MGEs are present in Nigerian P. mirabilis thus their potential in disseminating resistance.

show abstract

“…The increase of resistant isolates to beta lactam and quinolone antibiotics is a great concern for the empirical treatment of nosocomial infections and public health because these traits can be horizontally-transmitted to other isolates by plasmids (18)(19)(20)(21). In the recent years, increase of ESBLproducing E. coli isolates has been reported from different parts of the world, particularly Asia (3).…”

Section: Discussionmentioning

confidence: 99%

Quinolone Resistance Determinants qnr, qep, and aac(6’)-Ib-cr in Extended-Spectrum Β-Lactamase Producing Escherichia coli Isolated From Urinary Tract Infections in Tehran, Iran

Goudarzi

Fazeli

2017

Shiraz E-Med J

View full text Add to dashboard Cite

Background: Prevalence of plasmid mediated quinolone resistance in Escherichia coli clinical isolates is a serious problem in developing countries. Objectives:The aim of this study was to investigate quinolone resistance determinants among Extended-Spectrum B-Lactamases (ESBL)-producing E. coli recovered from patients with nosocomial urinary tract infection. Methods: A total of 290 E. coli isolates, obtained from patients with UTI, were included in this study. The phenotypic confirmatory test for ESBL production was performed by double disc synergy test and combined disk diffusion test. Kirby-Bauer Disk diffusion method was performed to test susceptibilities of ESBL-producing E. coli isolates to 15 antimicrobial agents. Isolates were screened for the presence of ESBL and plasmid-mediated quinolone resistance genes by polymerase chain reaction (PCR). Results: In the present study, 290 (71.7%) E. coli strains were recovered from 410 hospitalized patients with UTI, 51.7% of which were found to have ESBL positive results. In vitro, the susceptibilities of ESBL-producing E. coli strains showed that all isolates were resistant to amoxicillin and penicillin and resistance rates to other of antibiotics differed from 40% to 96%. Among the 150 ESBL positive isolates, frequencies of aac(6')- Ib, oqxA, oqxB, qnrA, qnrB, qnrS, and qepA were 74.7%, 8%, 4%, 3.3%, 1.3%, 2%, and 2.7%, respectively. Coexistence of bla CTX-M, bla TEM, bla CTX-M, and aac(6')-Ib were the most widely distributed resistance genotypes. Conclusions:The data of the present study revealed the high prevalence of plasmid-mediated quinolone resistance genes among ESBL-producing E. coli in the hospitals. The bla CTX-M genes were found to be the dominant ESBL-encoding gene.

show abstract

Prevalence of qnr , aac(6 ′ )-Ib-cr , qepA , and oqxAB in Escherichia coli Isolates from Humans, Animals, and the Environment

Cited by 165 publications

References 16 publications

Plasmid-Mediated OqxAB Is an Important Mechanism for Nitrofurantoin Resistance in Escherichia coli

Plasmid-Mediated OqxAB Is an Important Mechanism for Nitrofurantoin Resistance in Escherichia coli

Molecular screening of antibiotic-resistant determinants among multidrug-resistant clinical isolates of <i>Proteus mirabilis</i> from SouthWest Nigeria

Quinolone Resistance Determinants qnr, qep, and aac(6’)-Ib-cr in Extended-Spectrum Β-Lactamase Producing Escherichia coli Isolated From Urinary Tract Infections in Tehran, Iran

Contact Info

Product

Resources

About