High Prevalence of Quinolone Resistance Genes in Citrobacter freundii Isolated from Pet Turtles

ABSTRACTqnrBis the most common of the fiveqnrfamilies and has the greatest number of allelic variants. Almost two-thirds of theqnrBalleles have been reported inCitrobacterspp., and several were shown to be located on the chromosome. In this study, PCR was used to investigate the prevalence of plasmid-mediated quinolone resistance genes in 71 clinical isolates belonging to theCitrobacter freundiicomplex. Thirty-seven percent containedqnrBalleles, including 7 (qnrB32 to qnrB38) that were novel and 1 pseudogene, while none containedqnrA,qnrC,qnrD,qnrS, oraac(6′)-Ib-cr. When the strains were arrayed by related 16S rRNA sequence and further separated into subspecies by biochemical criteria, clustering ofqnrB-positive strains was evident. In only two strains withqnrB2andqnrB4was quinolone resistance transferable by conjugation, and only these strains contained the ISCR1sequence that is often associated withqnrBon plasmids. Five of 26qnrB-positive strains contained integrase genes, but these included the strains withqnrB2andqnrB4as well as two strains with other transmissible plasmids. In a fully sequenced genome ofCitrobacter youngae, a member of theC. freundiicomplex, another novelqnrBallele,qnrB39, occurs in a sequence of genes that is 90% identical to sequence surrounding integron-associatedqnrB4incorporated into plasmids. The chromosome ofCitrobacteris the likely source of plasmid-mediatedqnrB.

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High Prevalence of Plasmid-Mediated Quinolone Resistance Genes qnr and aac(6′)-Ib-cr in Clinical Isolates of Enterobacteriaceae from Nine Teaching Hospitals in China

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01558-08 ◽

2009 ◽

Vol 53 (2) ◽

pp. 847-847 ◽

Cited By ~ 1

Author(s):

Hong Yang ◽

Hongbin Chen ◽

Qiwen Yang ◽

Minjun Chen ◽

Hui Wang

Keyword(s):

Resistance Genes ◽

Quinolone Resistance ◽

Clinical Isolates ◽

Teaching Hospitals ◽

High Prevalence

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Trend of plasmid-mediated quinolone resistance genes at the Children’s Hospital in Tunisia

Journal of Medical Microbiology ◽

10.1099/jmm.0.062216-0 ◽

2014 ◽

Vol 63 (2) ◽

pp. 195-202 ◽

Cited By ~ 15

Author(s):

Nour El-Houda Jlili ◽

Samia Réjiba ◽

Hanen Smaoui ◽

Thomas Guillard ◽

Françoise Chau ◽

...

Keyword(s):

Escherichia Coli ◽

Resistance Genes ◽

Random Amplified Polymorphic Dna ◽

Enterobacter Cloacae ◽

Quinolone Resistance ◽

Children's Hospital ◽

Extended Spectrum ◽

High Prevalence ◽

Children’S Hospital ◽

Dna Pcr

The prevalence of plasmid-mediated quinolone resistance genes [qnr, aac(6′)-Ib-cr and qepA] was sought among Enterobacteriaceae strains obtained from the Children’s Hospital of Tunis (Tunisia). Non-duplicate isolates (n = 278) with resistance to extended-spectrum cephalosporins and collected in 2003, 2007, 2008 and 2009 were screened for qnr genes. Forty (14.4 %) isolates were qnr positive and were screened for the presence of the aac(6′)-Ib-cr and qepA genes. qnrB was detected in 21 Klebsiella pneumoniae, 11 Escherichia coli and 6 Enterobacter cloacae isolates. Sequence analysis of the qnrB amplicons revealed variants including 24 qnrB1, 11 qnrB2 and 3 qnrB6. qnrS (qnrS1 allele) was detected only in K. pneumoniae isolates, either alone (two isolates) or with the qnrB gene (one isolate). The qnrA, qnrC and qnrD genes were not found in any of the 278 isolates. No qnr-positive isolates carried the qepA gene. Pyrosequencing results showed that aac(6′)-Ib-cr, a variant of the aac(6′)-Ib gene, was present in 31 qnr-positive isolates (21 K. pneumoniae isolates, seven Escherichia coli isolates and three Enterobacter cloacae isolates). aac(6′)-Ib was also found either alone (two isolates) or in association with aac(6′)-Ib-cr (one isolate). Of the 40 qnr-positive isolates, 92.5, 82.5, 57.5, 85 and 82.5 % were non-susceptible to nalidixic acid, ciprofloxacin, levofloxacin, ofloxacin and norfloxacin, respectively, and all were extended-spectrum β-lactamase producers. Random amplified polymorphic DNA-PCR typing of these isolates showed 16, 8 and 5 different genotypes in K. pneumoniae, Escherichia coli and Enterobacter cloacae isolates, respectively. Our study highlights the high prevalence of qnr in association with aac(6′)-Ib-cr among Enterobacteriaceae isolates, even from children, who are patients not overtreated with quinolones.

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Characterization of Integrons and Quinolone Resistance in Clinical Escherichia coli Isolates in Mansoura City, Egypt

International Journal of Microbiology ◽

10.1155/2021/6468942 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Shaymaa H. Abdel-Rhman ◽

Rehab M. Elbargisy ◽

Dina E. Rizk

Keyword(s):

Escherichia Coli ◽

Resistance Genes ◽

Efflux Pump ◽

Quinolone Resistance ◽

Aminoglycoside Resistance ◽

Variable Regions ◽

Active Efflux ◽

E Coli ◽

High Prevalence ◽

Class I Integrons

Escherichia coli is a common pathogen in both humans and animals. Quinolones are used to treat infections caused by Gram-negative bacteria, but resistance genes emerged. Only scarce studies investigated the association between plasmid-mediated quinolone resistance (PMQR) genes and integrons in clinical isolates of E. coli. The current study investigated the prevalence of quinolone resistance and integrons among 134 clinical E. coli isolates. Eighty (59.70%) isolates were quinolone-resistant, and 60/134 (44.77%) isolates were integron positive with the predominance of class I integrons (98.33%). There was a significant association between quinolone resistance and the presence of integrons ( P < 0.0001 ). Isolates from Urology and Nephrology Center and Gastroenterology Hospital were significantly quinolone-resistant and integron positive ( P ≤ 0.0005 ). Detection of PMQR genes on plasmids of integron-positive isolates showed that the active efflux pump genes oqxAB and qepA had the highest prevalence (72.22%), followed by the aminoglycoside acetyltransferase gene (aac(6′)-Ib-cr, 66.67%) and the quinolone resistance genes (qnr, 61.11%). Amplification and sequencing of integrons’ variable regions illustrated that no quinolone resistance genes were detected, and the most predominant gene cassettes were for trimethoprim and aminoglycoside resistance including dfrA17, dfrB4, and dfrA17-aadA5. In conclusion, this study reported the high prevalence of PMQR genes and integrons among clinical E. coli isolates. Although PMQR genes are not cassette-born, they were associated with integrons’ presence, which contributes to the widespread of quinolone resistance in Egypt.

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Plasmid-Mediated Quinolone Resistance Genes in Enterobacteriaceae from American Crows: High Prevalence of Bacteria with VariableqnrBGenes

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01849-13 ◽

2013 ◽

Vol 58 (2) ◽

pp. 1257-1258 ◽

Cited By ~ 13

Author(s):

Dana Halová ◽

Ivo Papoušek ◽

Ivana Jamborova ◽

Martina Masarikova ◽

Alois Cizek ◽

...

Keyword(s):

Resistance Genes ◽

Quinolone Resistance ◽

High Prevalence ◽

American Crows

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High Prevalence of Plasmid-Mediated Quinolone Resistance Genes qnr and aac(6′)-Ib-cr in Clinical Isolates of Enterobacteriaceae from Nine Teaching Hospitals in China

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00830-08 ◽

2008 ◽

Vol 52 (12) ◽

pp. 4268-4273 ◽

Cited By ~ 66

Author(s):

Hong Yang ◽

Hongbin Chen ◽

Qiwen Yang ◽

Minjun Chen ◽

Hui Wang

Keyword(s):

Resistance Genes ◽

Direct Sequencing ◽

Quinolone Resistance ◽

Clinical Isolates ◽

Teaching Hospitals ◽

E Coli ◽

The Family ◽

High Prevalence ◽

Large Plasmids ◽

Widespread Dissemination

ABSTRACT Quinolone resistance is an emerging problem in China. To investigate the prevalence of the plasmid-mediated quinolone resistance genes qnr and aac(6′)-Ib-cr, a total of 265 clinical isolates of Escherichia coli, Klebsiella pneumoniae, Citrobacter freundii, and Enterobacter cloacae with ciprofloxacin MICs of ≥0.25 μg/ml were screened at nine teaching hospitals in China. The qnrA, qnrB, qnrS, and aac(6′)-Ib genes were detected by PCR. The aac(6′)-Ib-cr gene was further identified by digestion with BtsCI and/or direct sequencing. The qnr gene was present in significantly smaller numbers of isolates with cefotaxime MICs of <2 μg/ml than isolates with higher MICs (≥2.0 μg/ml) (20.6% and 42.1%, respectively; P < 0.05). aac(6′)-Ib-cr was present in 17.0% of the isolates tested, and 7.9% of the isolates carried both the qnr and the aac(6′)-Ib-cr genes. Among the isolates with cefotaxime MICs of ≥2.0 μg/ml, qnr and aac(6′)-Ib-cr were present in 65.7% and 8.6% of E. cloacae isolates, respectively; 65.5% and 21.8% of K. pneumoniae isolates, respectively; 63.3% and 26.7% of C. freundii isolates, respectively; and 6.5% and 16.9% of E. coli isolates, respectively. The 20 transconjugants showed 16- to 128-fold increases in ciprofloxacin MICs, 14 showed 16- to 2,000-fold increases in cefotaxime MICs, and 5 showed 8- to 32-fold increases in cefoxitin MICs relative to those of the recipient due to the cotransmission of bla CTX-M-14, bla CTX-M-3, bla DHA-1, bla SHV-2, and bla SHV-12 with the qnr and aac(6′)-Ib-cr genes. Southern hybridization analysis showed that these genes were located on large plasmids of different sizes (53 to 193 kb). These findings indicate the high prevalence of qnr and aac(6′)-Ib-cr in members of the family Enterobacteriaceae and the widespread dissemination of multidrug resistance in China.

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Prevalence of extended spectrum beta lactamase and plasmid mediated quinolone resistant genes in strains of Klebsiella pneumonia, Morganella morganii, Leclercia adecarboxylata and Citrobacter freundii isolated from poultry in South Western Nigeria

PeerJ ◽

10.7717/peerj.5053 ◽

2018 ◽

Vol 6 ◽

pp. e5053 ◽

Cited By ~ 6

Author(s):

Olajumoke R. Akinbami ◽

Samson Olofinsae ◽

Funmilola A. Ayeni

Keyword(s):

Resistance Genes ◽

Animal Husbandry ◽

Quinolone Resistance ◽

Klebsiella Pneumonia ◽

Citrobacter Freundii ◽

Beta Lactamase ◽

Beta Lactam ◽

Morganella Morganii ◽

Extended Spectrum Beta Lactamase ◽

Extended Spectrum

A serious concern is arising on the coexistence of extended-spectrum beta-lactamase (ESBL) and plasmid mediated quinolone resistance (PMQR) producing bacteria in animal husbandry, which could be transferred to humans, especially in strains that may not be routinely screened for resistance. This study therefore tested the prevalence of ESBL and PMQR genes in selected bacteria isolated from poultry faeces. Faecal droppings of birds were collected from 11 farms in five states in South Western Nigeria. Bacteria were isolated from the samples on cefotaxime supplemented plates and identified with MALDI-TOF. The MIC was determined using VITEK system and resistance genes were detected with PCR. A total of 350 strains were isolated from different samples and selected strains were identified as 23 Klebsiella pneumonia, 12 Morganella morganii, seven Leclercia adecarboxylata and one Citrobacter freundii. All the species were resistant to gentamycin, trimethoprim/sulphamethaxole, tobramycin, piperacillin, cefotaxime and aztreonam (except Morganella morganii strains which were mostly susceptible to aztreonam). All the tested strains were susceptible to imipenem, meropenem and amikacin. All Leclercia adecarboxylata strains were resistant to ceftazidime, cefepime and fosfomycin while all Morganella morganii strains were resistant to fosfomycin, moxifloxacin and ciprofloxacin. All tested species were generally sensitive to ciprofloxacin except Morganella morganii strains which were resistant to ciprofloxacin. The resistance to ciprofloxacin, ceftazidime, cefepime, tigercylin, colistin and fosfomycin were 65%, 40%, 23%,, 7%, 33%, 48% respectively while the prevalence of SHV, TEM and CTX genes were 42%, 63%, 35% respectively. 9.3% of the isolates had the three ESBL genes, 2.33% had qnrA gene, 4.65% had qnr B gene while none had qnrS gene. The most prevalent PMQR gene is Oqxb (25.58%) while 6.98% had the qep gene. Klebsiella pneumoniae generally had both ESBL and PMQR genes. The high prevalence of extended spectrum beta-lactamase genes in the studied strains calls for caution in the use of beta lactam antibiotics in poultry feeds. This is the first report of the occurrence of extended spectrum beta-lactamase and plasmid mediated quinolone resistance genes in Morganella morganii and Leclercia adecarboxylata strains isolated from poultry faeces.

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High fecal carriage of blaCTX-M, blaCMY-2, and plasmid-mediated quinolone resistance genes among healthy Korean people in a metagenomic analysis

Scientific Reports ◽

10.1038/s41598-021-84974-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jieun Kim ◽

Kye-Yeung Park ◽

Hoon-Ki Park ◽

Hwan-Sik Hwang ◽

Mi-Ran Seo ◽

...

Keyword(s):

Resistance Genes ◽

Gut Microbiome ◽

Antibiotic Resistance Genes ◽

Quinolone Resistance ◽

Upper Respiratory Tract ◽

Healthy Individuals ◽

Carriage Rate ◽

Fecal Carriage ◽

Metagenome Sequencing ◽

Tract Infections

AbstractTo characterize the carriage of antibiotic resistance genes (ARGs) in the gut microbiome of healthy individuals. Fecal carriage of ARGs was investigated in 61 healthy individuals aged 30 to 59 years through whole metagenome sequencing of the gut microbiome and a targeted metagenomic approach. The number of ARGs in the gut microbiome was counted and normalized per million predicted genes (GPM). In the Korean population, the resistome ranged from 49.7 to 292.5 GPM (median 89.7). Based on the abundance of ARGs, the subjects were categorised into high (> 120 GPM), middle (60‒120 GPM), and low (< 60 GPM) ARG groups. Individuals in the high ARG group tended to visit hospitals more often (P = 0.065), particularly for upper respiratory tract infections (P = 0.066), and carried more blaCTX-M (P = 0.008). The targeted metagenome approach for bla and plasmid-mediated quinolone resistance (PMQR) genes revealed a high fecal carriage rate; 23% or 13.1% of the subjects carried blaCTX-M or blaCMY-2, respectively. Regarding PMQR genes, 59% of the subjects carried PMQR, and 83% of them harboured 2‒4 PMQR genes (qnrB 44.3%, qnrS 47.5% etc.). The presence of blaCTX-M correlated with ARG abundance in the gut resistome, whereas PMQR genes were irrelevant to other ARGs (P = 0.176). Fecal carriage of blaCTX-M and PMQR genes was broad and multiplexed among healthy individuals.

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