Immunogen sequence: LLANLRHGGT VDEYLQDQLI VFMALANGVS RIKTGPVTLH TQTAIHFAEQ IAKAKFIVKK SEDEEDAAKD TYIIECQGIG MTNPNL. RTCD1 catalyzes the conversion of 3'-phosphate to a 2', 3'-cyclic phosphodiester at the end of RNA. The mechanism of action of the enzyme