抄録
We prepared several mutants of the J3⁄4 and P4 domains of Escherichia coli ribonuclease P (RNase P): A62G, A62U, G63C/G64C, A65G, A67G, U69A, U69G, U69C, U69Δ, and U69UU. Comparison of the ribozyme and holo enzyme reactions at various concentrations of magnesium ions showed that the presence of a bulge at U69 in the P4 domain was important in the holo enzyme. The results also showed that the conserved bases G63 and G64 in the J3⁄4 domain were important for efficient ribozyme reactions but were replaceable in the presence of the protein component. Our data showed that the bases in the J3⁄4 and P4 domains displayed different responses to the metal ions that were affected by the presence of the protein component.
