A strain which carries a mutation conferring clorobiocin resistance and temperature sensitivity for growth was isolated from Escherichia coli K12. Genetic mapping and the molecular weight of the gene product suggest that the mutation is in the cou gene, specifying a sub-unit of DNA gyrase. Nuclear o
A new conditional lethal mutator (dnaQ49) in Escherichia coli K12
โ Scribed by Horiuchi, Takashi ;Maki, Hisaji ;Sekiguchi, Mutsuo
- Publisher
- Springer
- Year
- 1978
- Tongue
- English
- Weight
- 652 KB
- Volume
- 163
- Category
- Article
- ISSN
- 0026-8925
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โฆ Synopsis
A conditional lethal mutator, dnaQ49, was found in Escherichia coli K12. The dnaQ49 mutation caused stimulation of rifampicin-, nalidixic acid- and streptomycin-resistant mutation frequencies 100 to 2000 fold at 30 degrees C and the frequencies were further increased 50 to 100 fold at 35 degrees C or higher temperatures. Cells carrying dnaQ49 were unable to grow in salt-free L-broth at 44.5 degrees C, and DNA synthesis but not protein synthesis of the cells was suppressed under the restrictive conditions. The dnaQ gene was located at about 5 min on the E. coli linkage map and the order of the genes residing in this region was determined to be ton A-dnaE-metD-dnaQ-pro A.
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