50S ribosomal protein L21 This protein binds to 23S rRNA in the presence of protein L20 (By similarity). BL1282 MYAIVKAGGHQEKVEVGDVILVNRLDAKKGDTVEFPVSLVVDGDKVTLAAADLAKVSVKAEVVNDEAKGPKISIQKYKNKTGVARRKGHRQKLTIVKITAIA 102 rplU RL21_BIFLO