Spontaneously-occurring rifampicin-resistant mutants that survive on low (20 micrograms ml-1) but not high drug concentrations (200 micrograms ml-1) have been isolated. One such mutation appears to map close to residue 650 on the beta structural gene. RNA polymerase from low-level resistant strains
Identification of an amber fragment of the β subunit of Escherichia coli RNA polymerase: A yardstick for measuring controls on RNA polymerase subunit synthesis
✍ Scribed by Glass, Robert E.
- Publisher
- Springer
- Year
- 1977
- Tongue
- English
- Weight
- 482 KB
- Volume
- 151
- Category
- Article
- ISSN
- 0026-8925
No coin nor oath required. For personal study only.
✦ Synopsis
An amber fragment of the beta subunit of Escherichia coli RNA polymerase has been recovered from strains carrying the rpoB12 amber mutation, indicating that the B12 mutation resides in the structural gene for the beta subunit. The fragment is readily assayed and can be used to determine the degree of expression of a single rpoB cistron in strains haploid or diploid for this region. These studies confirm that the bacterial mechanism, which can compensate for reduced translation of the beta message, operates by the co-ordinate induction of rpoB and rpoC. Furthermore, I show that rpo control depends upon cistron(s) located on the F' factor, KLF10, whose product(s) can act negatively in trans on rpoBC expression.
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