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]. | ||||
Substrate
| 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] |
Product
| 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] |
Schemes
| # | Name |
|---|---|
| 68 | 23S rRNA (adenine2503-C8)-methyltransferase, Radical SAM Superfamily |
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