AC MF_00772; DC Protein; auto TR HAMAP; MF_00772; -; 1; level=0 XX Names: OGT XX ID OGT DE RecName: Full=Methylated-DNA--protein-cysteine methyltransferase; DE EC=2.1.1.63; DE AltName: Full=6-O-methylguanine-DNA methyltransferase; DE Short=MGMT; DE AltName: Full=O-6-methylguanine-DNA-alkyltransferase; case GN Name=ogt; end case XX CC -!- FUNCTION: Involved in the cellular defense against the biological CC effects of O6-methylguanine (O6-MeG) and O4-methylthymine (O4-MeT) in CC DNA. Repairs the methylated nucleobase in DNA by stoichiometrically CC transferring the methyl group to a cysteine residue in the enzyme. This CC is a suicide reaction: the enzyme is irreversibly inactivated. CC -!- CATALYTIC ACTIVITY: CC Reaction=a 6-O-methyl-2'-deoxyguanosine in DNA + L-cysteinyl-[protein] CC = a 2'-deoxyguanosine in DNA + S-methyl-L-cysteinyl-[protein]; CC Xref=Rhea:RHEA:24000, Rhea:RHEA-COMP:10131, Rhea:RHEA-COMP:10132, CC Rhea:RHEA-COMP:11367, Rhea:RHEA-COMP:11368, ChEBI:CHEBI:29950, CC ChEBI:CHEBI:82612, ChEBI:CHEBI:85445, ChEBI:CHEBI:85448; EC=2.1.1.63; CC -!- CATALYTIC ACTIVITY: CC Reaction=a 4-O-methyl-thymidine in DNA + L-cysteinyl-[protein] = a CC thymidine in DNA + S-methyl-L-cysteinyl-[protein]; CC Xref=Rhea:RHEA:53428, Rhea:RHEA-COMP:10131, Rhea:RHEA-COMP:10132, CC Rhea:RHEA-COMP:13555, Rhea:RHEA-COMP:13556, ChEBI:CHEBI:29950, CC ChEBI:CHEBI:82612, ChEBI:CHEBI:137386, ChEBI:CHEBI:137387; CC EC=2.1.1.63; CC -!- SUBCELLULAR LOCATION: Cytoplasm. CC -!- MISCELLANEOUS: This enzyme catalyzes only one turnover and therefore is CC not strictly catalytic. According to one definition, an enzyme is a CC biocatalyst that acts repeatedly and over many reaction cycles. CC -!- SIMILARITY: Belongs to the MGMT family. XX DR Pfam; PF01035; DNA_binding_1; 1; trigger=no DR NCBIfam; TIGR00589; Ogt; 1; trigger=no DR PROSITE; PS00374; MGMT; 1; trigger=no XX KW Cytoplasm KW DNA damage KW DNA repair KW Transferase KW Methyltransferase XX GO GO:0003908; F:methylated-DNA-[protein]-cysteine S-methyltransferase activity GO GO:0006307; P:DNA dealkylation involved in DNA repair GO GO:0005737; C:cytoplasm XX FT From: OGT_THEKO (O74023) FT ACT_SITE 141 FT /note="Nucleophile; methyl group acceptor" FT Condition: C XX Size: 131-220; Related: None; Template: O74023; Q58924; P11742; Scope: Archaea Bacteria Fusion: Nter: None Cter: None Duplicate: None Plasmid: None Comments: None XX # Revision 1.22 2023/06/01 //