CATH Classification

Domain Context

CATH Clusters

Superfamily Methylated DNA-protein cysteine methyltransferase domain
Functional Family Bifunctional transcriptional activator/DNA repair enzyme Ada

Enzyme Information

2.1.1.63
Methylated-DNA--[protein]-cysteine S-methyltransferase.
based on mapping to UniProt P06134
(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 3.2.2.20 and EC 3.2.2.21, 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.
2.1.1.n11
Methylphosphotriester-DNA--[protein]-cysteine S-methyltransferase.
based on mapping to UniProt P06134
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 2.1.1.63 while the enzyme from Bacillus subtilis does not.

UniProtKB Entries (1)

P06134
ADA_ECOLI
Escherichia coli K-12
Bifunctional transcriptional activator/DNA repair enzyme Ada

PDB Structure

PDB 1SFE
External Links
Method X-RAY DIFFRACTION
Organism Escherichia
Primary Citation
Crystal structure of a suicidal DNA repair protein: the Ada O6-methylguanine-DNA methyltransferase from E. coli.
Moore, M.H., Gulbis, J.M., Dodson, E.J., Demple, B., Moody, P.C.
EMBO J.