Yu Wenli, Rao Jingxin, Zong Gongli, Zhang Wenchi, Zheng Mingyue, Zhang Rongzhen
School of Biotechnology and Key Laboratory of Industrial Biotechnology of Ministry of Education, Jiangnan University, Wuxi 214122, PR China.
Shanghai Institute of Materia Medica Chinese Academy of Sciences, Shanghai, China.
Int J Biol Macromol. 2025 Aug;319(Pt 3):145299. doi: 10.1016/j.ijbiomac.2025.145299. Epub 2025 Jun 16.
Polyketide synthases (PKSs) are among the most complex enzymatic systems in nature, responsible for synthesizing a broad array of polyketides including antibiotics, antifungal agents, and immunosuppressants. Cis-Acyltransferase (AT) PKSs, distinguished by their multiple modules, diverse catalytic domains, and engineering flexibility, hold significant promise for synthetic biology and natural product discovery. However, even minor alterations to individual domains can propagate structural and functional changes throughout the assembly line, posing a major challenge to the rational design of cis-AT PKSs for diverse polyketides production. This review explores the multidimensionality of cis-AT PKS design, with a focus on the selecting modular building blocks and designing catalytic domains based on the structural and mechanistic insights. Modifications to acyltransferases, ketosynthases, and ketoreductase-dehydratase-enoylreductases can fine-tune substrate specificity and stereochemical complexity, while engineering of the thioesterase domain enables controlled hydrolysis or cyclization for precise polyketide tailoring. Key future directions in cis-AT engineering are also highlighted. Collectively, these insights support the adaptation of cis-AT PKS systems to enhance product yields and expand the repertoire of accessible polyketides. This review provides a systematic overview of cis-AT PKS architecture and engineering strategies, offering a valuable resource for researchers in the field.
聚酮合酶（PKSs）是自然界中最复杂的酶系统之一，负责合成包括抗生素、抗真菌剂和免疫抑制剂在内的多种聚酮化合物。顺式酰基转移酶（AT）PKSs以其多个模块、多样的催化结构域和工程灵活性为特征，在合成生物学和天然产物发现方面具有巨大潜力。然而，即使对单个结构域进行微小改变，也可能在整个装配线上传播结构和功能变化，这对合理设计用于多种聚酮化合物生产的顺式AT PKSs构成了重大挑战。本综述探讨了顺式AT PKS设计的多维度性，重点是基于结构和机制见解选择模块化构建块和设计催化结构域。对酰基转移酶、酮合成酶和酮还原酶-脱水酶-烯酰还原酶的修饰可以微调底物特异性和立体化学复杂性，而硫酯酶结构域的工程改造能够实现可控的水解或环化，以精确修饰聚酮化合物。还强调了顺式AT工程未来的关键方向。总体而言，这些见解支持对顺式AT PKS系统进行改造，以提高产品产量并扩大可获得的聚酮化合物种类。本综述提供了顺式AT PKS结构和工程策略的系统概述，为该领域的研究人员提供了宝贵的资源。
