Figure 2.

Mg²⁺ or Mn²⁺ ions are essential for the T.maritima tRNase Z activity. The assays for in vitro 3′ processing of T.maritima pre-tRNA^Arg(₇₄CCA₇₆) by T.maritima wild-type tRNase Z in the presence of Mg²⁺, Mn²⁺ or Zn²⁺ alone (A), and in the presence of Mg²⁺ or Mn²⁺ together with Zn²⁺ (B). The pre-tRNA (0.1 pmol) was incubated with histidine-tagged tRNase Z (4 pmol) at 60°C for 10 min. The cleavage products were analyzed on a 10% polyacrylamide-8 M urea gel. I, input RNA.