title: Two new dfr genes in trimethoprim-resistant integron-negative Escherichia coli isolates.
abstract: Two Escherichia coli isolates resistant to trimethoprim but negative for integrons carried two new resistance genes, dfrA24 and dfrA26, remotely similar to one another and to the cassette-independent genes dfrA8 and dfrA9. The dfrA24 gene was not associated with known mobile elements, while dfrA26 was associated with the CR1 common region.
authors.affiliation: MTC, Clinical Microbiology, Karolinska Institute, Karolinska Hospital L2:02, Stockholm, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Grape
authors.forename: L
authors.initials: L
authors.lastname: Sundström
authors.forename: G
authors.initials: G
authors.lastname: Kronvall
mesh_terms: D024881:Drug Resistance, Bacterial / Q000235:genetics*; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics; D005798:Genes, Bacterial; D032023:Integrons; D008826:Microbial Sensitivity Tests; D016133:Polymerase Chain Reaction; D014296:Trimethoprim Resistance / Q000235:genetics*