title: Two new gene cassettes, dfr17 (for trimethoprim resistance) and aadA4 (for spectinomycin/streptomycin resistance), inserted in an Escherichia coli class 1 integron.
abstract: Two new gene cassettes, dfr17 and aadA4, inserted in a class 1 integron of Escherichia coli EC107, are described here. The dfr17 cassette encodes trimethoprim resistance and has 91% identity with the dfrVII dihydrofolate reductase gene. The aadA4 cassette confers resistance to spectinomycin and streptomycin and shows 94% identity with the aadA3 gene. The integron carrying the dfr17 and aadA4 cassettes was located on a conjugative plasmid, pEC1072.
authors.affiliation: Department of Microbiology, School of Medicine, Kaohsiung Medical University, 100, Shih-Chuan 1st Road, Taiwan, Republic of China.
authors.forename: C Y
authors.initials: CY
authors.lastname: Chang
authors.forename: L L
authors.initials: LL
authors.lastname: Chang
authors.forename: Y H
authors.initials: YH
authors.lastname: Chang
authors.forename: T M
authors.initials: TM
authors.lastname: Lee
authors.forename: Y H
authors.initials: YH
authors.lastname: Li
authors.forename: S F
authors.initials: SF
authors.lastname: Chang
mesh_terms: D004251:DNA Transposable Elements; D004352:Drug Resistance, Microbial / Q000235:genetics*; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics*; D029968:Escherichia coli Proteins / Q000235:genetics*; D000198:Spectinomycin / Q000494:pharmacology; D013307:Streptomycin / Q000494:pharmacology; D013762:Tetrahydrofolate Dehydrogenase / Q000235:genetics*; D014296:Trimethoprim Resistance / Q000235:genetics*
chemical_list: C405495:AADA4 protein, E coli; D004251:DNA Transposable Elements; D029968:Escherichia coli Proteins; D000198:Spectinomycin; D013762:Tetrahydrofolate Dehydrogenase; D013307:Streptomycin