The Genes Encoding Formamidopyrimidine and MutY DNA Glycosylases in Escherichia coli Are Transcribed as Part of Complex Operons
AUTOR(ES)
Gifford, Christine M.
FONTE
American Society for Microbiology
RESUMO
Escherichia coli formamidopyrimidine (Fpg) DNA glycosylase and MutY DNA glycosylase are base excision repair proteins that work together to protect cells from the mutagenic effects of the commonly oxidized guanine product 7,8-dihydro-8-oxoguanine. The genes encoding these proteins, fpg and mutY, are both cotranscribed as part of complex operons. fpg is the terminal gene in an operon with the gene order radC, rpmB, rpmG, and fpg. This operon has transcription initiation sites upstream of radC, in the radC coding region, and immediately upstream of fpg. There is a strong attenuator in the rpmG-fpg intergenic region and three transcription termination sites downstream of fpg. There is an additional site, in the radC-rpmB intergenic region, that corresponds either to a transcription initiation site or to an RNase E or RNase III cleavage site. mutY is the first gene in an operon with the gene order mutY, yggX, mltC, and nupG. This operon has transcription initiation sites upstream of mutY, in the mutY coding region, and immediately upstream of nupG. There also appear to be attenuators in the yggX-mltC and mltC-nupG intergenic regions. The order of genes in these operons has been conserved or partially conserved only in other closely related gram-negative bacteria, although it is not known whether the genes are cotranscribed in these other organisms.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=93923Documentos Relacionados
- The genes encoding endonuclease VIII and endonuclease III in Escherichia coli are transcribed as the terminal genes in operons
- The C-terminal domain of Escherichia coli MutY is involved in DNA binding and glycosylase activities
- Substrate recognition by Escherichia coli MutY using substrate analogs.
- Characterization of a mammalian homolog of the Escherichia coli MutY mismatch repair protein.
- Regulation of mutY and Nature of Mutator Mutations in Escherichia coli Populations under Nutrient Limitation