Isolation of a dihydrofolate reductase-deficient mutant of Escherichia coli.
نویسندگان
چکیده
A strain of Escherichia coli was isolated in which dihydrofolate reductase was not detected by an enzyme assay or by competition for antibody. This strain requires methionine, glycine, a purine, and thymidine for growth in addition to the auxotrophic requirements of the parent strain. It was found to be useful as a recipient of plasmids harboring dihydrofolate reductase genes.
منابع مشابه
Construction of a fol mutant strain of Escherichia coli for use in dihydrofolate reductase mutagenesis experiments.
A strain of Escherichia coli with the fol gene deleted and a kan gene inserted in its place was created for use in cloning and isolation of mutant dihydrofolate reductase. Southern blot analysis and dihydrofolate reductase enzyme assays confirmed the delta fol::kan genotype. A thyA mutation accompanied the fol deletion and is required for survival of a dihydrofolate reductase-deficient strain.
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The dihydrofolate reductase (fol) gene in Escherichia coli has been deleted and replaced by a selectable marker. Verification of the delta fol::kan strain has been accomplished using genetic and biochemical criteria, including Southern analysis of the chromosomal DNA. The delta fol::kan mutation is stable in E. coli K549 [thyA polA12 (Ts)] and can be successfully transduced to other E. coli str...
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عنوان ژورنال:
- Journal of bacteriology
دوره 164 1 شماره
صفحات -
تاریخ انتشار 1985