Effect of polyamines on isoleucyl-tRNA formation by rat-liver isoleucyl-tRNA synthetase.
Effect of polyamines on isoleucyl-tRNA formation by rat-liver isoleucyl-tRNA synthetase.
复制标题
多胺对大鼠肝脏异亮酰-tRNA 合成酶形成异亮酰-tRNA 的影响。
DOI：
--
复制
发表时间：
1978
期刊：
影响因子：
--
通讯作者：
S. Hirose
中科院分区：
文献类型：
--
作者：
K. Igarashi;K. Eguchi;M. Tanaka;S. Hirose
本文用SephadexG-200、DEAE-SephadexA-25和tRNA-Sepharose 4 B柱层析纯化的异亮氨酰-tRNA合成酶，研究了多胺对大鼠肝脏异亮氨酰-tRNA合成的影响。在50 mMK+的存在下，异亮氨酰-tRNA的形成被1.5 mM或更高浓度的Mg 2+显着抑制。然而，在反应混合物中加入精胺阻止了Mg 2+的抑制作用。在200 mMK+的存在下，添加精胺的反应混合物刺激异亮氨酰-tRNA的形成中存在的Mg 2+浓度从0到5 mM。虽然有效浓度是不同的，亚精胺表现出类似的刺激效果。当使用更大量的tRNA时，刺激所需的精胺的有效浓度更高。异亮氨酰-tRNA形成的多胺的刺激作用，反映在多肽的合成。当用甲酰胺处理的poly（A，U）作为信使RNA时，多胺刺激氨基酸的多肽合成，但多胺不刺激氨酰-tRNA的多肽合成。
The effect of polyamines on rat-liver isoelucyl-tRNA formation was studied using isoleucyl-tRNA synthetase purified by column chromatography successively on Sephadex G-200, DEAE-Sephadex A-25, and tRNA-Sepharose 4B. In the presence of 50 mMK+, isoleucyl-tRNA formation was inhibited markedly by 1.5 mM or higher concentrations of Mg2+. However, the addition of spermine to the reaction mixture prevented the inhibitory effect of Mg2+. In the presence of 200 mMK+, the addition of spermine to the reaction mixture stimulated isoleucyl-tRNA formation in the presence of Mg2+ concentrations from 0 to 5 mM. Although the effective concentration was different, spermidine exhibited a similar stimulative effect. The effective concentration of spermine required for stimulation was higher when larger amounts of tRNA were used. The stimulatory effect of isoleucyl-tRNA formation by polyamines was shown to reflect on polypeptide synthesis. When formaldehyde-treated poly(A,U) was used as messenger RNA, polypeptide synthesis from amino acids was stimulated by polyamines, but that from aminoacyl-tRNAs was not stimulated by polyamines.