Increased transformation frequency in E. coli.
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Calcium↗
Biomedical subjects
B Molholt
Publications and source records attributed to B Molholt.
Extragenic suppression of two ribosomal protein cistrons lying near the rif locus in Escherichia coli.
The experiments reported here involve temperature-sensitive mutations in two of five cistrons encoding 50S ribosomal proteins that lie near the rif locus in Escherichia coli. I selected spontaneous TS+ mutants able to grow at elevated temperatures in which the TS+ event takes place outside this tract of cistrons near rif. Six distinct classes of extragenic suppressors were found, five of which have been mapped. Two of these suppressors lie near 64 min, a region known to be rich in cistrons ribosomal proteins (Dennis and Nomura, 1975). The remaining three extragenic suppressors were located near 16.5, 47, and 86 min.
Bacterial Proteins↗
Temperature-sensitive RNA polymerase mutants with altered subunit synthesis and degradation.
A temperature-sensitive mutant having a lethal mutation in the gene for the beta subunit of RNA polymerase (nucleosidetriphosphate:RNA nucleotidyltransferase, EC 2.7.7.6) exhibits an apparent 2- to 3-fold decrease in the rates of both beta and beta' subunit synthesis at the non-permissive temperature, relative to total protein. In contrast, a temperature-sensitive mutant with a lethal mutation in the gene encoding beta' has a 5- to 6-fold increase in the rates of beta and beta' synthesis at 42 degrees. These beta and beta' mutants also exhibit rapid degradation of both subunits at the high temperature.
DNA-Directed RNA Polymerases↗