末端脱氧核苷酸转移酶在生物传感及核酸合成领域的应用*

末端脱氧核苷酸转移酶(terminal deoxynucleotidyl transferase, TdT)是聚合酶X家族中的一员,与典型的DNA聚合酶不同,TdT以恒温的无模板依赖的方式催化脱氧核糖核苷三磷酸(dNTP)聚合到寡核苷酸的3'羟基端来合成DNA。并且TdT对底物的耐受性高具有聚合修饰型dNTP的能力,如荧光修饰的dNTP、生物素修饰的dNTP,甚至人工碱基均可作为其良好底物。TdT的这些生化特性使其被广泛的应用在生物传感和核酸合成领域中,促进了许多基于核酸的工具和方法的发展,并为酶促从头合成DNA技术的发展奠定基础。介绍了TdT的性质,重点总结了它在其介导的生物检测技术、核酸的修饰技术以及酶促合成DNA技术三个方面的核心作用、目前面临的挑战以及未来研究的方向,以期促进TdT在生物传感器和核酸合成中的进一步应用。

Application of Terminal Deoxynucleotidyl Transferase in Biosensors and Nucleic Acid Synthesis

Terminal deoxynucleotidyl transferase (TdT) is a member of the polymerase X family. Unlike typical DNA polymerases, TdT incorporates nucleotides at the 3'-end of single stranded DNA oligo in a unique template-free manner. Moreover, the high tolerance of TdT to substrates allows it to polymerize modified dNTP. Fluorescence-modified dNTPs, biotin-modified dNTPs and even artificial bases can be used as good substrates. These biochemical properties of TdT make it widely used in the fields of biosensing and nucleic acid synthesis, promote the development of many nucleic acid-based tools and methods, and lay the foundation for the development of enzymatic de novo DNA synthesis technology. The latest progress of cartilage 3D bioprinting and the limitations of current technology are also explained.