Dipeptide seryl-histidine and related oligopeptides cleave DNA, protein, and a carboxyl ester
Dipeptide seryl-histidine and related oligopeptides cleave DNA, protein, and a carboxyl ester
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DOI：
10.1016/s0968-0896(00)00208-x
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发表时间：
2000-12-01
影响因子：
3.5
通讯作者：
Chen, XZ
中科院分区：
文献类型：
--
作者：
Li, YS;Zhao, YF;Chen, XZ
氨基酸组氨酸（His）和丝氨酸（ser）或类似于Ser的氨基酸在诸如丝氨酸和硫醇蛋白酶、脂肪酶和酯酶的多种酶的活性位点中一起作为关键催化氨基酸起作用。Ser和His也在遗传学上广泛分布的自我剪接蛋白的内含肽-外显肽连接处以及从它们剪接的归巢核酸内切酶的N-和C-末端保守。在这里，我们表明，二肽丝氨酰组氨酸（Ser-His）和相关的寡肽本身可以切割DNA，蛋白质，和酯对硝基苯基乙酸酯（p-NPA）在很宽的pH值和温度范围内。用Ser-His孵育的5 '端标记的DNA样品的变性聚丙烯酰胺凝胶电泳（PAGE）显示每个核苷酸位置两条带的模式，与3'-羟基和3 '-磷酸DNA切割片段的产生一致，正如Ser-His对磷酸二酯水解的预期。据我们所知，Ser-His是迄今报道的对多种天然底物显示切割活性的最短肽。二肽通过在内部或C-末端添加氨基酸残基而对变化的适应性，同时保留其多重切割活性，结合其在宽pH和温度范围内的反应性，证明了Ser/His二分体的进化能力，并引发了许多关于它在分子进化中可能发挥的作用的问题，作为选择具有增强的切割活性和靶特异性的寡肽的核心的潜在作用。(C)2000爱思唯尔科技有限公司版权所有。
The amino acids histidine (His) and serine (ser), or amino acids similar to Ser, function together as key catalytic amino acids in the active sites of such diverse enzymes as the serine- and thiol-proteases, lipases, and esterases. Ser and His are also conserved in the intein-extein junctions of the phylogenetically widespread self-splicing proteins and at the N- and C-termini of the homing endonucleases spliced from them. Here we show that the dipeptide seryl-histidine (Ser-His) and related oligopeptides can themselves cleave DNA, protein, and the ester p-nitrophenyl acetate (p-NPA) over wide ranges of pH and temperature. Denaturing polyacrylamide gel electrophoresis (PAGE) of 5'-end labeled DNA samples incubated with Ser-His reveals a pattern of two bands per nucleotide position, consistent with the generation of both 3'-hydroxyl and 3/-phosphate DNA cleavage fragments, as would be expected of phosphodiester hydrolysis by Ser-His. To the: best of our knowledge, Ser-His is the shortest peptide ever reported to show cleavage activity with multiple categories of natural substrates. The amenability of the dipeptide to variation through addition of amino acid residues, either internally or to the C-terminus while retaining its multiple cleavage activities, combined with its reactivity over wide ranges of pH and temperature, demonstrates the evolutionary capacity of the Ser/His dyad and evokes many questions about possible roles it may have played in molecular evolution and its]potential role as a core for selection of oligopeptides with enhanced cleavage activities and target specificity. (C) 2000 Elsevier Science Ltd. All rights reserved.