FIGURE 2.
γ-toxin cleavage requires a ribose 5′ of the scissile wobble nucleotide. The 17-mer oligonucleotide substrates are shown. The dC-6, dU-7, dA-11, and dC-12 substrates contain single deoxynucleosides in the anticodon loop, as indicated. Nuclease reaction mixtures (10 μL) contained 200 fmol 5′ 32P-labeled 17-mer substrates and γ-toxin as specified. The extents of 17-mer cleavage are plotted as a function of input γ-toxin.