Antibiotic resistance gene cassettes derived from the π interposon for use in E. coli and Streptomyces

The mercury resistance gene merA has often been found together with antibiotic resistance genes in human commensal Escherichia coli. To study this further, we analysed mercury resistance in collections of strains from various populations with different levels of mercury exposure and various levels of antibiotic resistance. The first population lived in France and had no known mercury exposure. The second lived in French Guyana and included a group of Wayampi Amerindians with a known high exposure to mercury. Carriage rates of mercury resistance were assessed by measuring the MIC and by detecting the merA gene. Mercury-resistant E. coli was found significantly more frequently in the populations that had the highest carriage rates of antibiotic-resistant E. coli and in parallel antibiotic resistance was higher in the population living in an environment with a high exposure to mercury, suggesting a possible co-selection. Exposure to mercury might be a specific driving force for the acquisition and maintenance of mobile antibiotic resistance gene carriage in the absence of antibiotic selective pressure.

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Identification and Characterization of Integron-Mediated Antibiotic Resistance among Shiga Toxin-Producing Escherichia coli Isolates

Applied and Environmental Microbiology ◽

10.1128/aem.67.4.1558-1564.2001 ◽

2001 ◽

Vol 67 (4) ◽

pp. 1558-1564 ◽

Cited By ~ 147

Author(s):

Shaohua Zhao ◽

David G. White ◽

Beilei Ge ◽

Sherry Ayers ◽

Sharon Friedman ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Shiga Toxin ◽

Antibiotic Resistance Gene ◽

Gene Encoding ◽

Gene Cassettes ◽

E Coli ◽

Class 1 Integrons ◽

Class 1

ABSTRACT A total of 50 isolates of Shiga toxin-producing Escherichia coli (STEC), including 29 O157:H7 and 21 non-O157 STEC strains, were analyzed for antimicrobial susceptibilities and the presence of class 1 integrons. Seventy-eight (n = 39) percent of the isolates exhibited resistance to two or more antimicrobial classes. Multiple resistance to streptomycin, sulfamethoxazole, and tetracycline was most often observed. Class 1 integrons were identified among nine STEC isolates, including serotypes O157:H7, O111:H11, O111:H8, O111:NM, O103:H2, O45:H2, O26:H11, and O5:NM. The majority of the amplified integron fragments were 1 kb in size with the exception of one E. coli O111:H8 isolate which possessed a 2-kb amplicon. DNA sequence analysis revealed that the integrons identified within the O111:H11, O111:NM, O45:H2, and O26:H11 isolates contained the aadA gene encoding resistance to streptomycin and spectinomycin. Integrons identified among the O157:H7 and O103:H2 isolates also possessed a similaraadA gene. However, DNA sequencing revealed only 86 and 88% homology, respectively. The 2-kb integron of the E. coli O111:H8 isolate contained three genes, dfrXII,aadA2, and a gene of unknown function, orfF, which were 86, 100, and 100% homologous, respectively, to previously reported gene cassettes identified in integrons found inCitrobacter freundii and Klebsiella pneumoniae. Furthermore, integrons identified among the O157:H7 and O111:NM strains were transferable via conjugation to another strain of E. coli O157:H7 and to several strains of Hafnia alvei. To our knowledge, this is the first report of integrons and antibiotic resistance gene cassettes in STEC, in particular E. coliO157:H7.

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Genomic surveillance of Escherichia coli ST131 identifies local expansion and serial replacement of subclones

10.1101/814731 ◽

2019 ◽

Cited By ~ 4

Author(s):

Catherine Ludden ◽

Arun Gonzales Decano ◽

Dorota Jamrozy ◽

Derek Pickard ◽

Dearbhaile Morris ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Resistance Gene ◽

Antibiotic Resistance Gene ◽

Gene Variants ◽

Term Care ◽

E Coli ◽

Esbl Gene ◽

Combining Data ◽

Clade C

AbstractEscherichia coli sequence type 131 (ST131) is a pandemic clone that is evolving rapidly with increasing levels of antimicrobial resistance. Here, we investigated an outbreak of E. coli ST131 producing extended spectrum β-lactamases (ESBLs) in a long-term care facility (LTCF) in Ireland by combining data from this LTCF (n=69) with other Irish (n=35) and global (n=690) ST131 genomes to reconstruct the evolutionary history and understand changes in population structure and genome architecture over time. This required a combination of short and long-read genome sequencing, de novo assembly, read mapping, ESBL gene screening, plasmid alignment and temporal phylogenetics. We found that clade C was the most prevalent (686 out of 794 isolates, 86%) of the three major ST131 clades circulating worldwide (A, B, C), and was associated with the presence of different ESBL alleles, diverse plasmids and transposable elements. Clade C was estimated to have emerged in ∼1985 and subsequently acquired different ESBL gene variants (blaCTX-M-14 vs blaCTX-M-15). An ISEcp1- mediated transposition of the blaCTX-M-15 gene further increased the diversity within Clade C. We discovered a local clonal expansion of a rare C2 lineage (C2_8) with a chromosomal insertion of blaCTX-M-15 at the mppA gene. This was acquired from an IncFIA plasmid. The C2_8 lineage clonally expanded in the Irish LTCF from 2006, displacing the existing C1 strain (C1_10) and highlighting the potential for novel ESBL-producing ST131 with a distinct genetic profile to cause outbreaks strongly associated with specific healthcare environments.ImportanceExtraintestinal pathogenic E. coli (ExPEC) ST131 is adapting in the context of antibiotic exposure, resulting in a pandemic with distinct genetic subtypes. Here, we track the evolution of antibiotic-resistance gene variants originally discovered in an ExPEC ST131 outbreak that was identified in a LTCF in Ireland. Analysis of 794 global ST131 genomes show that subclade C1 was associated with the initial infection outbreak, but that a new lineage from subclade C2 successfully displaced C1. This genetically distinct C2 subclade with a chromosomal insertion of a key antibiotic-resistance gene had clonally expanded within the LTCF. We provide new insights into the timing of genetic events driving the diversification of C2 subclades to show that that outbreak C2 strain likely evolved elsewhere before spreading to the LTCF. This study highlights the scope of antibiotic-resistance gene rearrangement within ST131, reinforcing the need to integrate genomic, epidemiological and microbiological approaches to understand ST131 transmission.

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Effect of β-lactam antibiotic resistance gene expression on the radio-resistance profile of E. coli O157:H7

Heliyon ◽

10.1016/j.heliyon.2018.e00999 ◽

2018 ◽

Vol 4 (12) ◽

pp. e00999 ◽

Cited By ~ 2

Author(s):

Ghizlane Gaougaou ◽

Yosra Ben-Fadhel ◽

Eric Déziel ◽

Monique Lacroix

Keyword(s):

Gene Expression ◽

Antibiotic Resistance ◽

Resistance Gene ◽

Antibiotic Resistance Gene ◽

Resistance Profile ◽

E Coli ◽

Lactam Antibiotic

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Distribution and Content of Class 1 Integrons in Different Vibrio cholerae O-Serotype Strains Isolated in Thailand

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.44.5.1315-1321.2000 ◽

2000 ◽

Vol 44 (5) ◽

pp. 1315-1321 ◽

Cited By ~ 82

Author(s):

Anders Dalsgaard ◽

Anita Forslund ◽

Oralak Serichantalergs ◽

Dorthe Sandvang

Keyword(s):

Antibiotic Resistance ◽

Vibrio Cholerae ◽

Resistance Gene ◽

Resistance Genes ◽

Antibiotic Resistance Gene ◽

Antibiotic Resistance Genes ◽

Gene Cassette ◽

Gene Cassettes ◽

Class 1 Integrons ◽

Class 1

ABSTRACT In this study, 176 clinical and environmental Vibrio cholerae strains of different O serotypes isolated in Thailand from 1982 to 1995 were selected and studied for the presence of class 1 integrons, a new group of genetic elements which carry antibiotic resistance genes. Using PCR and DNA sequencing, we found that 44 isolates contained class 1 integrons harboring the aadB,aadA2, blaP1, dfrA1, anddfrA15 gene cassettes, which encode resistance to gentamicin, kanamycin, and tobramycin; streptomycin and spectinomycin; β-lactams; and trimethoprim, respectively. Each cassette array contained only a single antibiotic resistance gene. Although resistance genes in class 1 integrons were found in strains from the same epidemic, as well as in unrelated non-O1, non-O139 strains isolated from children with diarrhea, they were found to encode only some of the antibiotic resistance expressed by the strains. Serotype O139 strains did not contain class 1 integrons. However, the appearance and disappearance of the O139 serotype in the coastal city Samutsakorn in 1992 and 1993 were associated with the emergence of a distinct V. cholerae O1 strain which contained the aadA2resistance gene cassette. A 150-kb self-transmissible plasmid found in three O1 strains isolated in 1982 contained the aadB gene cassette. Surprisingly, several strains harbored two integrons containing different cassettes. Thus, class 1 integrons containing various resistance gene cassettes are distributed among differentV. cholerae O serotypes of mainly clinical origin in Thailand.

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Improved antibiotic-resistance gene cassettes and omega elements for Escherichia coli vector construction and in vitro deletion/insertion mutagenesis

Gene ◽

10.1016/0378-1119(95)00108-i ◽

1995 ◽

Vol 160 (1) ◽

pp. 63-67 ◽

Cited By ~ 130

Author(s):

Mikhail F. Alexeyev ◽

Inna N. Shokolenko ◽

Timothy P. Croughan

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Resistance Gene ◽

Antibiotic Resistance Gene ◽

Insertion Mutagenesis ◽

Gene Cassettes ◽

Vector Construction

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The influence of antibiotic resistance gene carriage on biofilm formation by two Escherichia coli strains associated with urinary tract infections

Canadian Journal of Microbiology ◽

10.1139/cjm-2013-0633 ◽

2014 ◽

Vol 60 (2) ◽

pp. 105-111 ◽

Cited By ~ 6

Author(s):

Amy Huei Teen Teh ◽

Yi Wang ◽

Gary A. Dykes

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Urinary Tract ◽

Resistance Gene ◽

Biofilm Formation ◽

Antibiotic Resistance Gene ◽

Kanamycin Resistance ◽

Marker Genes ◽

E Coli ◽

Tract Infections

Urinary tract infections (UTI) caused by uropathogenic Escherichia coli are one of the most common forms of human disease. In this study, the effect of the presence of newly acquired antibiotic resistance genes on biofilm formation of UTI-associated E. coli strains was examined. Two clinical UTI-associated E. coli strains (SMC18 and SMC20) carrying different combinations of virulence genes were transformed with pGEM-T, pGEM-T::KmΔAmp, or pGEM-T::Km to construct ampicillin-resistant (KmSAmpR), kanamycin-resistant (KmRAmpS), or ampicillin- and kanamycin-resistant (KmRAmpR) strains. Transformed and wild-type strains were characterized for biofilm formation, bacterial surface hydrophobicity, auto-aggregation, morphology, and attachment to abiotic surfaces. Transformation with a plasmid carrying an ampicillin resistance gene alone decreased (p < 0.05) biofilm formation by SMC18 (8 virulence marker genes) but increased (p < 0.05) biofilm formation by SMC20 (5 virulence marker genes). On the other hand, transformation with a plasmid carrying a kanamycin resistance gene alone or both ampicillin and kanamycin resistance genes resulted in a decrease (p < 0.05) in biofilm formation by SMC18 but did not affect (p > 0.05) the biofilm formation by SMC20. Our results suggest that transformation of UTI-associated E. coli with plasmids carrying different antibiotic resistance gene(s) had a significant impact on biofilm formation and that these effects were both strain dependent and varied between different antibiotics.

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Characterization of antibiotic resistance integrons harbored by Romanian Escherichia coli uropathogenic strains

Revista Romana de Medicina de Laborator ◽

10.2478/rrlm-2020-0023 ◽

2020 ◽

Vol 28 (3) ◽

pp. 331-340

Author(s):

Mihaela Oprea ◽

Madalina Cornelia Militaru ◽

Adriana Simona Ciontea ◽

Daniela Cristea ◽

Violeta Cristea ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Antibiotic Resistance Gene ◽

Variable Region ◽

Phylogenetic Groups ◽

Gene Cassettes ◽

E Coli ◽

Class 1 ◽

Tract Infections

AbstractBecause little is known about the integrons which constitute an important means of spreading resistance in bacteria circulating in Romania, this study aimed to detect antibiotic resistance gene cassettes embedded in integrons in a convenient collection of 60 ciprofloxacin-resistant Escherichia coli isolates of various phylogroups, associated with community-acquired urinary tract infections. Characterization of the integrons was accomplished by PCR, restriction fragment length polymorphism typing, and DNA sequencing of each identified type. More than half of the tested E. coli strains were positive for integrons of class 1 (31 strains) or 2 (1 strain). These strains derived more frequently from phylogenetic groups A (15 of 21 strains), B1 (10 of 14 strains), and F (3 of 4 strains), respectively. While 20 strains carried class 1 integrons which could be assigned to nine types, eleven strains carried integrons that lacked the 3’-end conserved segment. The attempts made to characterize the gene cassettes located within the variable region of the various integrons identified in this study revealed the presence of genes encoding resistance to trimethoprim, aminoglycosides, beta-lactams or chloramphenicol. The evidence of transferable resistance determinants already established in the autochthonous E. coli strains highlights the need for improved control of resistance-carrying bacteria.

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