Nucleic acid-based enzymes have recently joined their proteinaceous counterparts as important biocatalysts. While RNA enzymes (ribozymes) are found in nature, deoxyribozymes or DNAzymes are man-made entities. Numerous ribozymes and DNAzymes have been identified by Darwinian selection methods to catalyze a broad array of chemical transformations. Despite these important advances, practical applications involving nucleic acid enzymes are often plagued by relatively poor pharmacokinetic properties and cellular uptake, rapid degradation by nucleases and/or by the limited chemical arsenal carried by natural DNA and RNA. In this review, the two main chemical approaches for the modification of nucleic acid-based catalysts, particularly DNAzymes, are described. These methods aim at improving the functional properties of nucleic acid enzymes by mitigating some of these shortcomings. In this context, recent developments in the post-SELEX processing of existing nucleic acid catalysts as well as efforts for the selection of DNAzymes and ribozymes with modified nucleoside triphosphates are summarized.

中文翻译：

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基于功能化核苷的核酸酶。

基于核酸的酶最近已作为重要的生物催化剂加入了它们的蛋白质对应物。尽管在自然界中发现了RNA酶（核酶），但脱氧核酶或DNA酶却是人造的。通过达尔文选择方法已经鉴定出许多核酶和DNA酶，以催化各种各样的化学转化。尽管取得了这些重要的进步，但涉及核酸酶的实际应用经常受到相对较弱的药代动力学特性和细胞摄取，核酸酶的快速降解和/或天然DNA和RNA携带的有限化学武库的困扰。在这篇综述中，描述了用于修饰基于核酸的催化剂，特别是DNA核酶的两种主要化学方法。这些方法旨在通过减轻这些缺点中的一些缺点来改善核酸酶的功能特性。在此背景下，总结了现有核酸催化剂的SELEX后处理的最新进展以及用修饰的三磷酸核苷选择DNA酶和核酶的努力。