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.
|Number of pages||7|
|Journal||Journal of Antimicrobial Chemotherapy|
|Publication status||Published - Sept 1987|
Bibliographical noteFunding Information:
This work was supported by a research grant from the Trent Regional Health Authority.