23S rRNA (uridine2552-2′-O)-methyltransferase (EC 2.1.1.166 Um(2552) 23S ribosomal RNA methyltransferase heat shock protein RrmJ RrmJ FTSJ Um2552 methyltransferase) is an enzyme with system name S-adenosyl-L-methionine:23S rRNA (uridine2552-2′-O-)-methyltransferase.