Abstract:

Non-ribosomal peptides (NRPs) represent a vital class of natural drugs, exhibiting a broad spectrum of biological activities including anticancer, antibiotic and immunosuppressive. Among U.S. Food and Drug Administration (FDA) approved drugs, fungal NRPs hold a prominent position, being the source of pioneering pharmacological agents like the immunosuppressant cyclosporine, antibacterial cephalosporin, as well as the antifungal echinocandins. These NRPs are synthesized through complex multimodular enzyme complexes known as non-ribosomal peptide synthetases (NRPSs), comprised of three core domains: adenylation (A), thiolation domain/peptidyl carrier protein (T/PCP) and condensation (C). These domains collectively form repetitive modules responsible for activating and incorporating specific amino acids or hydroxycarboxylic acid building blocks into the growing peptide chain. Beyond the core domains lie optional domains exemplified by epimerization (E), heterocyclization (Cy) and oxidation (Ox) domains, facilitating the customization of building blocks. The diversity in these domains and the variability in the number of modules within NRPS significantly contribute to the structural diversity of resulting skeletons. Furthermore, the distinct post-modification process applied to the structural skeleton yields potent pharmacological groups for NRPs, contributing significantly to both structural diversity and broadening their range of activities. This diversity not only provides extensive opportunities for the discovery of naturally sourced active NRPs but also opens avenues for modifications leading to the creation of non-natural NRPs via synthetic biological technology. To date, numerous strategies have been employed in the development of NRPs, including heterologous expression, transcriptional factor activation, precursor-directed biosynthesis, mutasynthesis, combinatorial biosynthesis and enzyme engineering. The collective accumulation of foundational knowledge alongside synthetic biology techniques enhances the potential for further advancements in NRPs development. This review summarizes the progress in fungal NRPs research, encompassing their bioactivities, biosynthetic pathways, enzymatic mechanisms and metabolic engineering. A comprehensive understanding of fungal NRPs biosynthesis not only aids in comprehending the corresponding enzymatic assembly mechanism but also serves as crucial guidance and a reference point for advancing novel fungal NRPs and their derivatives, thereby paving the way for the development of new potential drug candidates derived from NRPs.

Key words: fungal non-ribosomal peptide, non-ribosomal peptide synthetase, biosynthesis, enzymatic mechanism, metabolic engineering

摘要：

真菌源非核糖体肽类（NRP）药物因其活性优异、结构多样而备受关注。至今美国食品药品监督管理局（FDA）已批准了数十种真菌NRP药物，包括环孢菌素、头孢菌素和棘白菌素等重磅药物。这些NRP药物均由非核糖体肽合成酶（NRPSs）催化形成，其多样化的结构域和模块数量决定了产物骨架的多样性，从而为天然源活性NRPs的开发提供了广阔的空间。此外，骨架结构上的特殊后修饰过程往往为NRP药物提供了强效的药效基团，进一步扩充了NRPs结构与活性的多样性。本文综述了真菌NRP药物的研究进展，主要涵盖药物活性、生物合成途径、酶学机理和代谢工程改造等。真菌NRP药物生物合成途径的深入了解不仅有助于理解相关的酶学组装机制，还有望为新型真菌NRP药物及其衍生物的深度开发提供重要的指导和参考。

关键词: 真菌非核糖体肽, 非核糖体肽合成酶, 生物合成, 酶学组装机制, 代谢工程