Reaction: 23S rRNA (adenine2503-C8)-methyltransferase List of reactions

Reaction name: 23S rRNA (adenine2503-C8)-methyltransferase Reaction type: cognate
EC number:2.1.1.224 Kegg ID: Rhea ID:42635
Directionality: reversible Curation status: valid Classification: public
Description: The enzyme methylates adenosine at position 2503 of 23S rRNA by a radical mechanism, transferring a CH2 group from S-adenosyl-L-methionine while retaining the hydrogen at the C-8 position of the adenine. Cfr first transfers an CH2 group to a conserved cysteine (Cys338 in Staphylococcus aureus), the generated radical from a second S-adenosyl-L-methionine then attacks the methyl group, extracting a hydrogen. The formed radical forms a covalent intermediate with the adenine group of the tRNA.
Curator notes:The enzyme will also methylate 2-methyladenine produced by the action of EC 2.1.1.192 [23S rRNA (adenine2503-C2)-methyltransferase].
ID Type Compound ID Name Stoichiometry Curator notes
chebi 59789 S-adenosyl-L-methionine zwitterion 2
chebi 74411 AMP(1-) residue 1 Represents adenosine2503 in 23S rRNA
chebi 33738 di-mu-sulfido-diiron(1+) 2 Represents reduced [2Fe-2S]-[ferredoxin]
ID Type Compound ID Name Stoichiometry Curator notes
chebi 17319 5'-deoxyadenosine 1
chebi 74543 8-methyladenosine 5'-monophosphate(1-) residue 1 Represents 8-methyladenosine2503 in 23S rRNA
chebi 57856 S-adenosyl-L-homocysteine zwitterion 1
chebi 57844 L-methionine zwitterion 1
chebi 33737 di-mu-sulfido-diiron(2+) 2 Represents oxidized [2Fe-2S]-[ferredoxin]

Reaction

23S rRNA (adenine2503-C8)-methyltransferase

2 + + 2 + + + + 2
S-adenosyl-L-methionine zwitterion
59789
AMP(1-) residue
74411
di-mu-sulfido-diiron(1+)
33738
5'-deoxyadenosine
17319
8-methyladenosine 5'-monophosphate(1-) residue
74543
S-adenosyl-L-homocysteine zwitterion
57856
L-methionine zwitterion
57844
di-mu-sulfido-diiron(2+)
33737

EC: 2.1.1.224 | IntEnz: 2.1.1.224 | Kegg: 2.1.1.224 | BioCyc: 2.1.1.224 | BRENDA: 2.1.1.224