Peptide acceptors in the leucine, phenylalanine transfer reaction.
Peptide acceptors in the leucine, phenylalanine transfer reaction.
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亮氨酸、苯丙氨酸转移反应中的肽受体。
DOI：
10.1016/s0021-9258(19)43150-5
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发表时间：
1973
期刊：
影响因子：
--
通讯作者：
R. Soffer
中科院分区：
文献类型：
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作者：
R. Soffer
确定的二肽和三肽在亮氨酰、苯丙氨酰-tRNA-蛋白转移酶催化的反应中作为受体进行了测试。接受的标准是抑制14 C-氨基酸从tRNA到蛋白质的αs1-酪蛋白依赖性酶促转移的能力以及反应混合物中特定肽依赖性放射性产物的存在。在包含 19 个不同 NH2 末端残基的肽中，只有那些含有精氨酸、赖氨酸以及较小程度的组氨酸的肽满足这些标准。使用苯丙氨酰或亮氨酰-tRNA 的结果相似。发现抑制作用与 αs1-酪蛋白具有竞争性。当Lys-Ala-Ala用作苯丙氨酸的受体时，产物被分离并鉴定为Phe-Lys-Ala-Ala。发现所有含有NH2-末端1-精氨酸或1-赖氨酸残基的肽都充当受体；然而，d-Arg-d-Val 不活跃。在每个系列中，观察到Ki值有相当大的变化，这表明除了对NH2末端碱性氨基酸的绝对要求之外，该反应中的受体底物特异性还受到其他残基的影响。
Defined di- and tripeptides were tested as acceptors in the reaction catalyzed by leucyl, phenylalanyl-tRNA-protein transferase. Criteria for acceptance were ability to inhibit the αs1-casein-dependent enzymatic transfer of14C-amino acid from tRNA to protein and the presence in reaction mixtures of a specific peptide-dependent radioactive product. Among peptides comprising 19 different NH2-terminal residues, only those with arginine, lysine and, to a lesser extent, histidine fulfilled these criteria. Results were similar using phenylalanyl or leucyl-tRNA. Inhibition was found to be competitive with αs1-casein. When Lys-Ala-Ala was used as acceptor for phenylalanine, the product was isolated and identified as Phe-Lys-Ala-Ala.All peptides containing an NH2-terminall-arginine orl-lysine residue were found to function as acceptors; however,d-Arg-d-Val was inactive. In each series a considerable variation inKivalues was observed, suggesting that in addition to an absolute requirement for an NH2-terminal basic amino acid, acceptor substrate specificity in this reaction is also influenced by other residues.