title: Conjugal transfer of imipenem resistance in Bacteroides fragilis.
abstract: Transfer of imipenem resistance in Bacteroides fragilis was studied. Clinical isolate B. fragilis 10-73 was highly resistant to imipenem. Imipenem resistance was transferred from 10-73 to B. fragilis strain TM4000 at a frequency of 10(-6)/input recipient by a filter mating technique. The resistance could also be retransferred. B. fragilis 10-73 and both primary and secondary transcipients produced an imipenem-hydrolyzing metallo-beta-lactamase. Acquisition of imipenem resistance correlated with the appearance of plasmid DNA with a size (ca. 13.6 kb) similar to that of the donor strain. TM4000 transformed by electroporation with purified DNA of the 13.6-kb plasmid pBFUK1 produced the metallo-beta-lactamase and was resistant to imipenem. Transfer was resistant to DNase treatment and no transfer was seen with a sterile filtrate of the donor culture. It is suggested that gene transfer in B. fragilis has the properties of a conjugation system rather than those of transformation or transduction.
authors.affiliation: Institute of Anaerobic Bacteriology, Gifu University School of Medicine, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Bandoh
authors.forename: K
authors.initials: K
authors.lastname: Watanabe
authors.forename: Y
authors.initials: Y
authors.lastname: Muto
authors.forename: Y
authors.initials: Y
authors.lastname: Tanaka
authors.forename: N
authors.initials: N
authors.lastname: Kato
authors.forename: K
authors.initials: K
authors.lastname: Ueno
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001441:Bacteroides fragilis / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D003227:Conjugation, Genetic / Q000187:drug effects*; D004269:DNA, Bacterial / Q000235:genetics; D004352:Drug Resistance, Microbial; D004587:Electrophoresis, Agar Gel; D015378:Imipenem / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D010641:Phenotype; D010957:Plasmids / Q000235:genetics; D014162:Transfection; D001618:beta-Lactamases / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D015378:Imipenem; D001618:beta-Lactamases