PMID:390304
Citation |
Smith, DR and Calvo, JM (1979) Regulation of dihydrofolate reductase synthesis in Escherichia coli. Mol. Gen. Genet. 175:31-8 |
---|---|
Abstract |
Two clones from the Clarke-Carbon Escherichia coli colony bank were resistant to inhibition by trimethoprim, a potent inhibitor of dihydrofolate reductase. Both clones had elevated levels of dihydrofolate reductase. Furthermore, trimethoprim resistance and elevated enzyme levels were associated with ColE1 plasmids that carried DNA from the trkC ksgA pdxA region of the E. coli chromosome. Plasmid pLC1437a was shown by two criteria to carry the structural gene for dihydrofolate reductase: 1) A partial diploid containing plasmid pLC1437a produced a kinetically-recognizable dihydrofolate reductase that was not present in the parent haploid strain. 2) Plasmid pLC1437a coded for dihydrofolate reductase in vitro. A 1,000 base pair fragment of plasmid pLC1437a containing fol was used as a probe to measure fol mRNA in a mutant strain isolated by Sheldon and Brenner (Molec. gen. Genet. 147, 91-97, 1976). The mutation in this strain, which results in constitutively-high levels of dihydrofolate reductase and in the inability of the strain to grow at 42 degrees C, is cis dominant (Sheldon and Brenner, 1976). The results of kinetic hybridization and pulse-labeling experiments indicated that the regulatory mutant produced elevated levels of dihydrofolate reductase in response to an increased rate of synthesis of fol mRNA. |
Links | |
Keywords |
DNA Restriction Enzymes/metabolism; Escherichia coli/enzymology; Escherichia coli/genetics; Genes; Mutation; Plasmids; RNA, Bacterial/biosynthesis; RNA, Messenger/biosynthesis; Tetrahydrofolate Dehydrogenase/biosynthesis; Tetrahydrofolate Dehydrogenase/genetics |
edit table |
Main Points of the Paper
Please summarize the main points of the paper.
Materials and Methods Used
Please list the materials and methods used in this paper (strains, plasmids, antibodies, etc).
Phenotype Annotations
See Help:AnnotationTable for details on how to edit this table.
<protect>
Phenotype of | Taxon Information | Genotype Information (if known) | Condition Information | OMP ID | OMP Term Name | ECO ID | ECO Term Name | Notes | Status |
---|---|---|---|---|---|---|---|---|---|
edit table |
</protect>
Notes
References
See Help:References for how to manage references in omp dev.