title: New trimethoprim-resistant dihydrofolate reductase cassette, dfrXV, inserted in a class 1 integron.
abstract: The nucleotide sequence of a plasmid-borne trimethoprim resistance gene from a commensal fecal Escherichia coli isolate revealed a new dihydrofolate reductase gene, dfrXV, which occurred as a gene cassette integrated in a site-specific manner in a class 1 integron. The new gene shows 84% nucleotide identity and the predicted protein shows 90% amino acid identity with dfrI and DHFR type I, respectively. Genes for spectinomycin resistance, aadA1 [ant (3")-Ia], and sulfonamide resistance, sulI, were located downstream of dfrXV in a manner identical to that in pLMO229.
authors.affiliation: Department of Medical Microbiology, University of the Witwatersrand, and the South African Institute for Medical Research, Johannesburg, South Africa. petera@mail.saimr.wits.ac.za
authors.forename: P V
authors.initials: PV
authors.lastname: Adrian
authors.forename: M
authors.initials: M
authors.lastname: DU Plessis
authors.forename: K P
authors.initials: KP
authors.lastname: Klugman
authors.forename: S G
authors.initials: SG
authors.lastname: Amyes
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003227:Conjugation, Genetic; D004926:Escherichia coli / Q000235:genetics*; D005493:Folic Acid Antagonists / Q000494:pharmacology; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D013762:Tetrahydrofolate Dehydrogenase / Q000235:genetics*; D014296:Trimethoprim Resistance / Q000235:genetics*
chemical_list: D005493:Folic Acid Antagonists; D013762:Tetrahydrofolate Dehydrogenase