Cellular repair mechanism of 5-formyluracil.
5-Formyluracil (fU) is an oxidative DNA base damage. This damage has been suggested to be mutagenic and but enzymatic repair of the damage is little known. In this study, repair enzymes that recognize fU have been studied. Kinetic analysis of the repair activity of E. coli 3-methyladenine DNA glycosylase II (AlkA) showed that fU was removed by AlkA with the efficiency comparable to 7-methylguanine. We also examined the participation of the methyl-directed mismatch repair system. The affinity of MutS to the fU:G mispair was essentially similar to that of the T:G mispair that was most efficiently recognized by the MutSLH system. These results suggest two distinct repair pathways of fU in E. coli.
Masaoka
A
A
Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Japan.
Kobayashi
M
M
Terato
H
H
Ohyama
Y
Y
Ide
H
H
D020137:Base Pair Mismatch; D019757:Carbon-Oxygen Lyases / Q000378:metabolism*; D003001:Cloning, Molecular; D004249:DNA Damage; D045647:DNA Glycosylases; D004260:DNA Repair; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase; D043223:Deoxyribonuclease IV (Phage T4-Induced); D004926:Escherichia coli / Q000201:enzymology*; D029968:Escherichia coli Proteins; D009699:N-Glycosyl Hydrolases / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D014498:Uracil / Q000031:analogs & derivatives*
D029968:Escherichia coli Proteins; D011994:Recombinant Proteins; C007777:5-formyluracil; D014498:Uracil; D043223:Deoxyribonuclease IV (Phage T4-Induced); C468972:endonuclease IV, E coli; D045647:DNA Glycosylases; D009699:N-Glycosyl Hydrolases; C076131:DNA-3-methyladenine glycosidase II; D019757:Carbon-Oxygen Lyases; D043603:DNA-(Apurinic or Apyrimidinic Site) Lyase