Figure 1.

Sequence of the 7S11 deoxyribozyme (E) in complex with its RNA substrates (R, L) and formation of the 2′,5′-branched RNA (20,22). In the presence of a bivalent metal cation, the 2′-OH of the bulged adenosine on L performs a nucleophilic attack on the α-phosphate of the 5′-terminal triphosphate of R. In this study, the fluorescent dye Bimane (Bim) was attached at the γ-(S)-phosphate of R. The products of the reaction are a 2′,5′-branched RNA and the released pyrophosphate (PP_i), shown here as the fluorescent Bim conjugate (Bim-PP_i).