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问题:

氨基酰-tRNA合成酶催化反应的特点是 A.氨基酰-tRNA合成酶具有绝对特异性 B.催化氨基

氨基酰-tRNA合成酶催化反应的特点是

A.氨基酰-tRNA合成酶具有绝对特异性

B.催化氨基酸的-COOH与tRNA的3'-OH生成酯键

C.此酶还有校正活性,即催化酯键水解的活性

D.该酶在活化氨基酸的同时需要消耗ATP


  参考答案

正确答案:ABCD

136.答案:ABCD

[考点] 参加蛋白质生物合成的物质

[分析] 氨基酰-tRNA合成酶对氨基酸及tRNA两种底物都能高度特异地识别,具有绝对特异性。它催化氨基酸的羧基与 tRNA3,羟基间脱水形成酯键相连。此酶还有校正活性,实际上是催化酯键水解的活性。另外其催化氨基酸与tRNA反应时,还需要有ATP参加,在合成氨基酰-tRNA的同时,ATP转变为AMP并放出PPi

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