El'skaya A, Negrutskii B
Eur J Biochem. 1987 Apr 1;164(1):65-9. doi: 10.1111/j.1432-1033.1987.tb10993.x.
The interaction between tRNA conformers inactive in aminoacylation and leucyl-tRNA synthetase has been investigated. Heat inactivation of the enzyme in the presence of inactive tRNA conformers is shown to lead to a marked increase of inactivation rate while active tRNA conformers, on the other hand, reveal a protecting effect. To study the properties of the enzyme complexed with different tRNA conformers limited proteolysis has been used. Active tRNA conformers are found to protect leucyl-tRNA synthetase against hydrolysis while inactive ones tend to intensify it. Inactive tRNA conformers are also shown to inhibit the aminoacylation of native tRNA in vitro. On the basis of these data biologically inactive conformers of animal tRNA are assumed to form an unproductive complex with leucyl-tRNA synthetase and the structure of the enzyme involved in such interaction is supposed to be more labile and 'extended' than that in complex with active tRNA conformers.
对氨酰化无活性的tRNA构象异构体与亮氨酰-tRNA合成酶之间的相互作用进行了研究。结果表明，在无活性tRNA构象异构体存在的情况下，该酶的热失活会导致失活速率显著增加，而活性tRNA构象异构体则具有保护作用。为了研究与不同tRNA构象异构体复合的酶的性质，采用了有限蛋白酶解方法。发现活性tRNA构象异构体可保护亮氨酰-tRNA合成酶不被水解，而无活性的tRNA构象异构体则倾向于增强水解作用。无活性tRNA构象异构体在体外也被证明可抑制天然tRNA的氨酰化作用。基于这些数据，推测动物tRNA的生物学无活性构象异构体与亮氨酰-tRNA合成酶形成了非生产性复合物，并且参与这种相互作用的酶的结构比与活性tRNA构象异构体复合时的结构更不稳定且“伸展”。
