Characterization of In111, a class 1 integron that carries the extended-spectrum Î²-lactamase geneblaIBC-1

ABSTRACT During a survey conducted to evaluate the incidence of class B carbapenemase (metallo-β-lactamase [MBL])-producing Pseudomonas aeruginosa strains from hospitals in Majorca, Spain, five clinical isolates showed a positive Etest MBL screening test result. In one of them, strain PA-SL2, the presence of a new bla VIM derivative (bla VIM-13) was detected by PCR amplification with bla VIM-1-specific primers followed by sequencing. The bla VIM-13-producing isolate showed resistance to all β-lactams (except aztreonam), gentamicin, tobramycin, and ciprofloxacin. VIM-13 exhibited 93% and 88% amino acid sequence identities with VIM-1 and VIM-2, respectively. bla VIM-13 was cloned in parallel with bla VIM-1, and the resistance profile conferred was analyzed both in Escherichia coli and in P. aeruginosa backgrounds. Compared to VIM-1, VIM-13 conferred slightly higher levels of resistance to piperacillin and lower levels of resistance to ceftazidime and cefepime. VIM-13 and VIM-1 were purified in parallel as well, and their kinetic parameters were compared. The k cat/K m ratios for the antibiotics mentioned above were in good agreement with the MIC data. Furthermore, EDTA inhibited the activity of VIM-13 approximately 25 times less than it inhibited the activity of VIM-1. VIM-13 was harbored in a class 1 integron, along with a new variant (Ala108Thr) of the aminoglycoside-modifying enzyme encoding gene aacA4, which confers resistance to gentamicin and tobramycin. Finally, the VIM-13 integron was apparently located in the chromosome, since transformation and conjugation experiments consistently yielded negative results and the bla VIM-13 probe hybridized only with the genomic DNA.

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Incidence and Characterization of Integrons, Genetic Elements Mediating Multiple-Drug Resistance, in AvianEscherichia coli

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.43.12.2925 ◽

1999 ◽

Vol 43 (12) ◽

pp. 2925-2929 ◽

Cited By ~ 165

Author(s):

Lydia Bass ◽

Cynthia A. Liebert ◽

Margie D. Lee ◽

Anne O. Summers ◽

David G. White ◽

...

Keyword(s):

Antibiotic Resistance ◽

Resistance Gene ◽

Multiple Drug Resistance ◽

Marker Gene ◽

Clinical Isolates ◽

Multiple Antibiotic Resistance ◽

Class 1 Integron ◽

E Coli ◽

Class 1

ABSTRACT Antibiotic resistance among avian bacterial isolates is common and is of great concern to the poultry industry. Approximately 36% (n = 100) of avian, pathogenic Escherichia coli isolates obtained from diseased poultry exhibited multiple-antibiotic resistance to tetracycline, oxytetracycline, streptomycin, sulfonamides, and gentamicin. Clinical avian E. coli isolates were further screened for the presence of markers for class 1 integrons, the integron recombinase intI1 and the quaternary ammonium resistance gene qacEΔ1, in order to determine the contribution of integrons to the observed multiple-antibiotic resistance phenotypes. Sixty-three percent of the clinical isolates were positive for the class 1 integron markersintI1 and qacEΔ1. PCR analysis with the conserved class 1 integron primers yielded amplicons of approximately 1 kb from E. coli isolates positive for intI1 andqacEΔ1. These PCR amplicons contained the spectinomycin-streptomycin resistance gene aadA1. Further characterization of the identified integrons revealed that many were part of the transposon Tn21, a genetic element that encodes both antibiotic resistance and heavy-metal resistance to mercuric compounds. Fifty percent of the clinical isolates positive for the integron marker gene intI1 as well as for theqacEΔ1 and aadA1 cassettes also contained the mercury reductase gene merA. The correlation between the presence of the merA gene with that of the integrase and antibiotic resistance genes suggests that these integrons are located in Tn21. The presence of these elements among avianE. coli isolates of diverse genetic makeup as well as inSalmonella suggests the mobility of Tn21 among pathogens in humans as well as poultry.

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Antimicrobial Resistance, Extended-Spectrum β-Lactamase Productivity, and Class 1 Integrons in Escherichia coli from Healthy Swine

Journal of Food Protection ◽

10.4315/0362-028x.jfp-14-445 ◽

2015 ◽

Vol 78 (8) ◽

pp. 1442-1450 ◽

Cited By ~ 17

Author(s):

KANJANA CHANGKAEW ◽

APIRADEE INTARAPUK ◽

FUANGFA UTRARACHKIJ ◽

CHIE NAKAJIMA ◽

ORASA SUTHIENKUL ◽

...

Keyword(s):

Escherichia Coli ◽

Antimicrobial Resistance ◽

Intestinal Flora ◽

Class 1 Integron ◽

Potential Health ◽

Gene Cassettes ◽

E Coli ◽

Class 1 Integrons ◽

Extended Spectrum ◽

Class 1

Administration of antimicrobials to food-producing animals increases the risk of higher antimicrobial resistance in the normal intestinal flora of these animals. The present cross-sectional study was conducted to investigate antimicrobial susceptibility and extended-spectrum β-lactamase (ESBL)–producing strains and to characterize class 1 integrons in Escherichia coli in healthy swine in Thailand. All 122 of the tested isolates had drug-resistant phenotypes. High resistance was found to ampicillin (98.4% of isolates), chloramphenicol (95.9%), gentamicin (78.7%), streptomycin (77.9%), tetracycline (74.6%), and cefotaxime (72.1%). Fifty-four (44.3%) of the E. coli isolates were confirmed as ESBL-producing strains. Among them, blaCTX-M (45 isolates) and blaTEM (41 isolates) were detected. Of the blaCTX-M-positive E. coli isolates, 37 carried the blaCTX-M-1 cluster, 12 carried the blaCTX-M-9 cluster, and 5 carried both clusters. Sequence analysis revealed blaTEM-1, blaTEM-135, and blaTEM-175 in 38, 2, and 1 isolate, respectively. Eighty-seven (71%) of the 122isolates carried class 1 integrons, and eight distinct drug-resistance gene cassettes with seven different integron profiles were identified in 43 of these isolates. Gene cassettes were associated with resistance to aminoglycosides (aadA1, aadA2, aadA22, or aadA23), trimethoprim (dfrA5, dfrA12, or dfrA17), and lincosamide (linF). Genes encoding β-lactamases were not found in class 1 integrons. This study is the first to report ESBL-producing E. coli with a class 1 integron carrying the linF gene cassette in swine in Thailand. Our findings confirm that swine can be a reservoir of ESBL-producing E. coli harboring class 1 integrons, which may become a potential health risk if these integrons are transmitted to humans. Intensive analyses of animal, human, and environmental isolates are needed to control the spread of ESBL-producing E. coli strains.

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Characterization of a novel class 1 integron InSW39 and a novel transposon Tn5393k identified in an imipenem-nonsusceptible Salmonella Typhimurium strain in Sichuan, China

Diagnostic Microbiology and Infectious Disease ◽

10.1016/j.diagmicrobio.2020.115263 ◽

2021 ◽

Vol 99 (3) ◽

pp. 115263

Author(s):

Liu Yao ◽

Yinhuan Ding ◽

Manlin Ding ◽

Xiangjin Yan ◽

Feiyang Zhang ◽

...

Keyword(s):

Salmonella Typhimurium ◽

Class 1 Integron ◽

Typhimurium Strain ◽

Class 1

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Bacteremia caused by an Acinetobacter junii strain harboring class 1 integron and diverse DNA mobile elements

The Journal of Infection in Developing Countries ◽

10.3855/jidc.3747 ◽

2014 ◽

Vol 8 (05) ◽

pp. 666-669 ◽

Cited By ~ 4

Author(s):

German M Traglia ◽

Marisa Almuzara ◽

Elisabet Vilacoba ◽

Alicia Tuduri ◽

Gabriela Neumann ◽

...

Keyword(s):

Molecular Characterization ◽

Renal Transplant Patient ◽

Transplant Patient ◽

Mobile Elements ◽

Ocular Infection ◽

Class 1 Integron ◽

Acinetobacter Junii ◽

Genomic Plasticity ◽

Class 1

Introduction: Infections caused by Acinetobacter junii are rarely reported. However, some outbreaks of septicemia in neonates and pediatric oncology patients, as well as meningitis, peritonitis, and ocular infection have been described. Since it is highly infrequent to find the molecular characterization of A. junii strains in literature, in this study we described the molecular characterization of A. junii isolates recovered from blood samples of a renal transplant patient. Methodology: The case was defined as a catheter-related bacteremia caused by A. junii. The patient responded favorably after catheter removal and treatment with ciprofloxacin. Results and Conclusion: The complete molecular characterization of the isolate showed that it harbored a class 1 integron and diverse DNA mobile elements. This explains its genomic plasticity for acquiring antimicrobial resistance determinants and for adapting to a nosocomial niche.

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