Mutagenesis, by methylating and ethylating agents, in mutH, mutL, mutS, and uvrD mutants of Salmonella typhimurium LT2.
AUTOR(ES)
Shanabruch, W G
RESUMO
Salmonella typhimurium LT2 mutH, mutL, mutS, and uvrD mutants were especially sensitive to mutagenesis by both the recA+-dependent mutagen methyl methane sulfonate and the recA+-independent mutagen ethyl methane sulfonate, but not to mutagenesis by agents such as 4-nitroquinoline-1-oxide and UV irradiation. Similarly, these mutator strains were very sensitive to mutagenesis by the methylating agents N-methyl-N'-nitro-N-nitrosoguanidine and N-methyl-N-nitrosourea. The increased susceptibility to mutagenesis by small alkylating agents due to mutH, mutL, mutS, and uvrD mutations was not accompanied by an increased sensitivity to killing by these agents. Various models are discussed in an effort to explain why strains thought to be deficient in methyl-instructed mismatch repair are sensitive to mutagenesis by methylating and ethylating agents.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=217339Documentos Relacionados
- Mutation detection with MutH, MutL, and MutS mismatch repair proteins.
- Identification and characterization of the mutL and mutS gene products of Salmonella typhimurium LT2.
- Bacterial genes mutL, mutS, and dcm participate in repair of mismatches at 5-methylcytosine sites.
- Identification of the uvrD gene product of Salmonella typhimurium LT2.
- Site-specific protein modification to identify the MutL interface of MutH