Suppression of dnaE nonsense mutations by pcbA1.
AUTOR(ES)
Maki, H
RESUMO
DNA polymerase III has been recognized as the required replication enzyme in Escherichia coli. The synthesis subunit of DNA polymerase III holoenzyme (alpha subunit) is encoded by the dnaE gene. We have reported that E. coli cells can survive and grow in the absence of a functional dnaE gene product if DNA polymerase I and the pcbA1 mutation are present. Existing mutations in the dnaE gene have been conditionally defective thermolabile mutations. We report here construction of nonsense mutations in the dnaE gene by use of a temperature-sensitive suppressor mutation to permit survival at the permissive temperature (32 degrees C). Introduction of the pcbA1 mutation eliminated the temperature-sensitive phenotype. We confirmed by immunoblotting the lack of detectable alpha subunit at 43 degrees C.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=210027Documentos Relacionados
- Map location of the pcbA mutation and physiology of the mutant.
- Mutator action by Escherichia coli strains carrying dnaE mutations
- Suppression of polar effects of nonsense mutations by ultraviolet irradiation.
- Genetic Analysis of DNA Replication in Bacteria: dna B Mutations That Suppress dnaC Mutations and dnaQ Mutations That Suppress dnaE Mutations in SALMONELLA TYPHIMURIUM
- Escherichia coli thymidylate synthase: amino acid substitutions by suppression of amber nonsense mutations.