Recent advances in chemoenzymatic synthesis of important steroids

doi:10.12211/2096-8280.2024-002

Abstract

Abstract:

Steroids exhibit a range of biological activities and are commonly described as the ‘key to life’ in nature. Steroidal-based medications have emerged as the second largest pharmaceutical category following antibiotics, owing to their remarkable bioactivities such as anti-infective, anti-inflammatory, anti-allergic, and antitumor properties. This category encompasses more than 400 drug compounds, representing approximately 17% of FDA-approved medications. The synthesis of steroidal products continues to attract significant attention due to their diverse bioactivities and physicochemical characteristics in pharmaceutical applications. With the increasing demand for steroidal drugs and the fluctuating availability of sapogenin resources, the use of Mycobacteria to convert inexpensive phytosterols to produce key intermediates for steroid drugs has been established as the most mature and sustainable industrial route. However, the complex structure of steroids, particularly their highly oxygenated skeleton, poses challenges for the well-established semi-synthesis route of complex steroid medications. Recent strides in bioinformatics and genetics have significantly advanced the studies on synthesis of steroidal compounds. This review highlights recent advancements in the synthesis of high-value steroids, including the diverse steroid drug intermediate production via external steroidal modifying enzymes expression in engineered Mycobacteria, chemo-enzymatic synthesis of complex steroids, and yeast-based de novo synthesis. It specifically highlights the significant achievements in the chemo-enzymatic synthesis, which combines the precise site- and stereoselectivity of enzymatic transformations with the efficiency of chemosynthesis, enabling the concise synthesis of complex steroidal products. Recent advancements in chemoenzymatic strategies, especially those involving P450 hydroxylase, 3-sterone-Δ¹-dehydrogenase, reductase, and enzyme cascades, have significantly contributed to the efficient and straightforward synthesis of complex steroid medications. On this basis, the future research opportunities and challenges are also discussed, aiming to provide a reference for the efficient development of more value-added steroid compounds, including the development of new generation steroid intermediates, the discovery of novel steroid biocatalysts, and the establishment of steroid synthesis pathways in mycobacteria.

Key words: steroids, chassis strains, chemoenzymatic, regio- and stereoselective, enzyme cascade

摘要：

甾体化合物因其多功能生物活性和理化特性备受生物医药行业的高度重视，被誉为自然界的“生命之钥”。随着植物甾醇代谢途径的不断解析，国内逐渐形成了“植物甾醇原料-甾体药物中间体-甾体药物”的工业合成路线。日益发展的甾药行业需要不断开发新的合成技术推进甾体药物自上而下高效合成。基于生物信息学、合成生物学、代谢工程以及酶工程的快速发展，甾体化合物的合成技术也取得了重大突破。本文对重要甾体化合物的最新合成进展，包括甾体药物中间体的多样化合成、复杂甾体的化学酶法合成和酵母从头合成植物甾醇原料等方面进行了综述，特别强调了近年来P450羟化酶、3-甾酮-Δ¹-脱氢酶、还原酶以及酶级联参与的化学酶法在高效简易合成复杂甾体药物中的代表性工作；在此基础上，也从新一代甾药中间体的开发、新型甾体生物催化剂的挖掘、以分枝杆菌为底盘的甾体合成途径的构建等方面对甾体化合物未来的研究机会和挑战进行了展望。

关键词: 甾体化合物, 底盘菌株, 化学酶法, 区域-立体选择性, 酶级联

CLC Number:

Q816

Mengmeng ZHENG, Benben LIU, Zhi LIN, Xudong QU. Recent advances in chemoenzymatic synthesis of important steroids[J]. Synthetic Biology Journal, 2024, 5(5): 941-959.

郑梦梦, 刘犇犇, 林芝, 瞿旭东. 重要甾体化合物的化学酶法合成研究进展[J]. 合成生物学, 2024, 5(5): 941-959.

Figures/Tables 8

Fig. 1 Structures of some steroidal precursors, key intermediates and steroidal drugs

Fig. 2 Diversified production of steroid intermediates in Mycobacteria

Fig. 3 Chemoenzymatic synthesis of 9,11-secosterols (5,6)

Fig. 4 Chemoenzymatic synthesis of C19-functionalized steroids

Fig. 5 Chemoenzymatic synthesis of C14-functionalized steroids

Fig. 6 3-Sterone-Δ1-dehydrogenase involved in the chemoenzymatic synthesis of pine steroids

Fig. 7 Reductase-mediated chemoenzymatic synthesis of steroids

Fig. 8 Enzyme cascades in chemoenzymatic synthesis of steroids

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