IUBMB Enzyme Nomenclature


Accepted name: 23S rRNA (cytidine1920-2'-O)-methyltransferase

Reaction: S-adenosyl-L-methionine + cytidine1920 in 23S rRNA = S-adenosyl-L-homocysteine + 2'-O-methylcytidine1920 in 23S rRNA

Other name(s): TlyA (ambiguous)

Systematic name: S-adenosyl-L-methionine:23S rRNA (cytidine1920-2'-O)-methyltransferase

Comments: The bifunctional enzyme from Mycobacterium tuberculosis 2'-O-methylates cytidine1920 in helix 69 of 23S rRNA and cytidine1409 in helix 44 of 16S rRNA (cf. EC, 16S rRNA (cytidine1409-2'-O)-methyltransferase). These methylations result in increased susceptibility to the antibiotics capreomycin and viomycin.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:


1. Johansen, S.K., Maus, C.E., Plikaytis, B.B. and Douthwaite, S. Capreomycin binds across the ribosomal subunit interface using tlyA-encoded 2'-O-methylations in 16S and 23S rRNAs. Mol. Cell 23 (2006) 173-182. [PMID: 16857584]

2. Maus, C.E., Plikaytis, B.B. and Shinnick, T.M. Mutation of tlyA confers capreomycin resistance in Mycobacterium tuberculosis. Antimicrob. Agents Chemother. 49 (2005) 571-577. [PMID: 15673735]

[EC created 2011]

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