Rapid detection of a specific trimethoprim resistance gene using a biotinylated DNA probe.
A DNA probe specific for the dihydrofolate reductase (DHFR) type I gene was labelled with biotin by the process of nick-translation and used to screen 83 independently-derived trimethoprim R plasmids from Enterobacteriaceae. Hybridization was detected using streptavidine and a biotin-conjugated alkaline phosphatase to generate an insoluble coloured precipitate following the addition of an appropriate dye. Sixty-eight plasmids (81.9%) hybridized with the probe for DHFR type I. The method could be adapted for use with any antibiotic resistance gene for which a suitable DNA probe is available and has none of the drawbacks associated with the use of radioactively-labelled DNA in hybridization techniques.
Carter
G I
GI
Department of Microbiology, University Hospital, Queen's Medical Centre, Nottingham, UK.
Towner
K J
KJ
Slack
R C
RC
D000469:Alkaline Phosphatase / Q000378:metabolism; D001710:Biotin / Q000378:metabolism; D004247:DNA / Q000032:analysis; D009693:Nucleic Acid Hybridization; D010957:Plasmids; D013762:Tetrahydrofolate Dehydrogenase / Q000235:genetics; D014296:Trimethoprim Resistance / Q000235:genetics*
D001710:Biotin; D004247:DNA; D013762:Tetrahydrofolate Dehydrogenase; D000469:Alkaline Phosphatase