THE RNA MOIETY OF RIBONUCLEASE-P IS THE CATALYTIC SUBUNIT OF THE ENZYME
THE RNA MOIETY OF RIBONUCLEASE-P IS THE CATALYTIC SUBUNIT OF THE ENZYME
复制标题
DOI：
10.1016/0092-8674(83)90117-4
复制
发表时间：
1983-01-01
期刊：
影响因子：
64.5
通讯作者：
ALTMAN, S
中科院分区：
文献类型：
--
作者：
GUERRIERTAKADA, C;GARDINER, K;ALTMAN, S
从大肠杆菌（M1 RNA）和枯草芽孢杆菌（P-RNA）中纯化的RNase P RNA片段可以在含有60或10 mM Mg2+ 1 mM亚精胺的缓冲液中切割tRNA前体分子。在这些条件下，RNA起着真正的催化剂的作用，而酶的蛋白质部分单独没有表现出催化活性。如前所述，在含有5-10 mM Mg2+（不含亚精胺）的缓冲液中，这两种亚基都是酶活性所必需的。在低浓度Mg2+存在的情况下，在体外重组实验中，来自一个物种的RNA和蛋白质亚基可以与来自另一个物种的亚基互补。当使用大肠杆菌4.5S RNA的前体作为底物时，只有与大肠杆菌M1 RNA形成的酶复合物和来自任何一种细菌的蛋白质部分具有活性。
The RNA moieties of RNase P purified from Escherichia coli (M1 RNA) and Bacillus subtilis (P-RNA) can cleave tRNA precursor molecules in buffers containing 60 or 10 mM Mg2+ plus 1 mM spermidine. The RNA acts as a true catalyst under these conditions whereas the protein moieties of the enzymes alone show no catalytic activity. In buffers containing 5-10 mM Mg2+ (in the absence of spermidine) both kinds of subunits are required for enzymatic activity, as shown previously. In the presence of low concentrations of Mg2+, in vitro, the RNA and protein subunits from one species can complement subunits from the other species in reconstitution experiments. When the precursor to E. coli 4.5S RNA is used as a substrate, only the enzyme complexes formed with M1 RNA from E. coli and the protein moieties from either bacterial species are active.