TAR克隆技术及其在微生物次级代谢产物研究中的应用

微生物次级代谢产物结构多样、种类丰富，是新药发现的重要来源。微生物次级代谢产物由特定生物合成基因簇编码合成，通常与微生物的生长繁殖无关。由于实验室可培养微生物的数量较少，而且多数可培养微生物存在基因簇沉默的现象，严重阻碍了微生物来源药物的研究和开发。微生物生物合成基因簇的异源表达及生物合成相应的次级代谢产物已逐渐成为发现新颖活性化合物的有效手段之一。作为研究微生物次级代谢产物的重要工具，基于TAR(transformation associated recombination)克隆技术的异源表达策略可实现绝大多数基因簇的完整异源表达。本文从TAR克隆技术的原理、应用和策略改进3个方面，总结了基于TAR克隆技术的微生物次级代谢产物异源生物合成的研究进展，为研究和开发新型微生物来源药物提供方法学借鉴。

Application of TAR cloning in microbial secondary metabolites

Microbial secondary metabolites have been a major source for drug discovery and development due to their structural novelty and diversity. Microbial secondary metabolites, typically encoded by specific biosynthetic gene cluster(BGC), are non-essential for the growth and propagation of the microbes. Despite the abundant existence of microbes, the majority of them are unculturable under laboratory conditions. Moreover, given that most of the BGCs from culturable microbes are silent, the discovery of novel microbial secondary metabolites has been hampered. Recently, the heterologous expression of BGCs has become an attractive approach to discover various microbial secondary metabolites, among which TAR-based heterologous expression is one of the important tools. This review summarized the principle of TAR, the applications and the advanced strategies of TAR-based methods for heterologous expression of secondary metabolites, which may help the advancements of drug discovery and development from microbial sources.