IUBMB Enzyme Nomenclature


Accepted name: 27S pre-rRNA (guanosine2922-2'-O)-methyltransferase

Reaction: S-adenosyl-L-methionine + guanosine2922 in 27S pre-rRNA = S-adenosyl-L-homocysteine + 2'-O-methylguanosine2922 in 27S pre-rRNA

Other name(s): Spb1p (gene name); YCL054W (gene name)

Systematic name: S-adenosyl-L-methionine:27S pre-rRNA (guanosine2922-2'-O-)-methyltransferase

Comments: Spb1p is a site-specific 2'-O-ribose RNA methyltransferase that catalyses the formation of 2'-O-methylguanosine2922, a universally conserved position of the catalytic center of the ribosome that is essential for translation. 2'-O-Methylguanosine2922 is formed at a later stage of the processing, during the maturation of of the 27S pre-rRNA. In absence of snR52, Spb1p can also catalyse the formation of uridine2921 [1].

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


1. Lapeyre, B. and Purushothaman, S.K. Spb1p-directed formation of Gm2922 in the ribosome catalytic center occurs at a late processing stage. Mol. Cell 16 (2004) 663-669. [PMID: 15546625]

2. Bonnerot, C., Pintard, L. and Lutfalla, G. Functional redundancy of Spb1p and a snR52-dependent mechanism for the 2'-O-ribose methylation of a conserved rRNA position in yeast. Mol. Cell 12 (2003) 1309-1315. [PMID: 14636587]

[EC created 2010]

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