EC 220.127.116.11: Methylated-DNA--[protein]-cysteine S-methyltransferase
(1) DNA (containing 6-O-methylguanine) + protein L-cysteine = DNA (without 6-O-methylguanine) + protein S-methyl-L-cysteine. (2) DNA (containing 4-O-methylthymine) + protein L-cysteine = DNA (without 4-O-methylthymine) + protein S-methyl-L-cysteine.
- This protein is involved in the repair of methylated DNA.
- Unlike EC 18.104.22.168 and EC 22.214.171.124, which remove the methylated base leaving an apurinic/apyrimidinic site, this enzyme transfers the methyl group from the methylated DNA to an internal cysteine residue, leaving an intact nucleotide.
- Since the methyl transfer is irreversible, the enzyme can only catalyze a single turnover.
- 6-O-methylguanine-DNA methyltransferase
- Ada (gene name)
- Ogt (gene name)
- MGT1 (gene name)
- MGMT (gene name)
EC 2.1.1.n11: Methylphosphotriester-DNA--[protein]-cysteine S-methyltransferase
DNA (containing Sp-methylphosphotriester) + protein L-cysteine = DNA (without Sp-methylphosphotriester) + protein S-methyl-L-cysteine.
- This protein is involved in the repair of Sp diastereomers of DNA methylphosphotriester lesions.
- This enzyme catalyzes only one turnover and therefore is not strictly catalytic.
- The enzyme from the bacterium Escherichia coli also has the activity of EC 126.96.36.199 while the enzyme from Bacillus subtilis does not.
DNA (containing Sp-methylphosphotriester):[protein] L-cysteine methyltransferase
Protein family (Pfam)
Domain description: Metal binding domain of Ada
Domain description: Ada-like domain superfamily
Domain description: Ada DNA repair, metal-binding
Class: Alpha Beta
Architecture: 3-Layer(aba) Sandwich
Topology: DNA Methylphosphotriester Repair Domain
Homology: DNA Methylphosphotriester Repair DomainOccurring in:
Class: Small proteins
Fold: Ada DNA repair protein, N-terminal domain (N-Ada 10)
Superfamily: Ada DNA repair protein, N-terminal domain (N-Ada 10)Occurring in: