23S rRNA (uridine<sup>2479</sup>-2'-O)-methyltransferase (, AviRb) is an enzyme with systematic name S-adenosyl-L-methionine:23S rRNA (uridine<sup>2479</sup>-2'-O)-methyltransferase. This enzyme catalyses the following chemical reaction
Streptomyces viridochromogenes produces the antibiotic avilamycin A which binds to the 50S ribosomal subunit to inhibit protein synthesis.