Any feedback?
Please rate this page
(literature.php)
(0/150)

BRENDA support

Literature summary for 2.1.1.224 extracted from

  • Schwalm, E.; Grove, T.; Booker, S.; Boal, A.
    Crystallographic capture of a radical S-adenosylmethionine enzyme in the act of modifying tRNA (2016), Science, 352, 309-312 .
    View publication on PubMedView publication on EuropePMC
Search for more literature for 2.1.1.224

Natural Substrates/ Products (Substrates)

Natural Substrates Organism Comment (Nat. Sub.) Natural Products Comment (Nat. Pro.) Rev. Reac.
2 S-adenosyl-L-methionine + adenine2503 in 23S rRNA + 2 reduced [2Fe-2S] ferredoxin Escherichia coli
-
 S-adenosyl-L-homocysteine + L-methionine + 5'-deoxyadenosine + 8-methyladenine2503 in 23S rRNA + 2 oxidized [2Fe-2S] ferredoxin
-
 ?

Organism

Organism UniProt Comment Textmining
Escherichia coli
-
-
-

Substrates and Products (Substrate)

Substrates Comment Substrates Organism Products Comment (Products) Rev. Reac.
2 S-adenosyl-L-methionine + adenine2503 in 23S rRNA + 2 reduced [2Fe-2S] ferredoxin
-
 Escherichia coli S-adenosyl-L-homocysteine + L-methionine + 5'-deoxyadenosine + 8-methyladenine2503 in 23S rRNA + 2 oxidized [2Fe-2S] ferredoxin
-
 ?

Synonyms

Synonyms Comment Organism
Cfr
-
 Escherichia coli
radical S-adenosylmethionine enzyme
-
 Escherichia coli

Cofactor

Cofactor Comment Organism Structure
reduced [2Fe-2S] ferredoxin
-
 Escherichia coli
S-adenosyl-L-methionine
-
 Escherichia coli

General Information

General Information Comment Organism
additional information although SAM is the source of the appended methyl carbon in the reactions catalyzed by RlmN and Cfr, these enzymes operate by a mechanism that is distinctly different from that of typical SAM-dependent methyltransferases. As radical SAM (RS) enzymes, RlmN and Cfr employ very similar radical-based mechanisms of catalysis, initiated by the abstraction of a hydrogen atom from a Cys-appended methyl group via a 5'-deoxyadenosyl 5'-radical. Subsequent attack of the resulting methylene radical upon the carbon atom undergoing methylation affords a protein/RNA cross-linked intermediate whose resolution requires prior proton abstraction from C2 (RlmN) or C8 (Cfr) of the substrate by an unidentified base. Conversion of the intermediate to the methylated product has also been demonstrated in the Cfr reaction. The proximity (5.0 A) of the Cys 355 side chain (the proposed site of thiyl radical formation) to the sulfur atom of Met176, a strictly conserved residue in RlmN and Cfr, might allow formation of a transient thiosulfuranyl radical Escherichia coli
physiological function Cfr modifies C8 of A2503 in 23S rRNA conferring resistance to multiple classes of antibiotics. A2503 is also methylated at C8 by RlmN, which is both evolutionarily and mechanistically related to Cfr. Methylation of C8 of A2503 is the only known in vivo activity of Cfr, while RlmN also installs a C2 methyl group at adenosine 37 Escherichia coli