State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University , Shanghai 200030, People's Republic of China.
Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York , Buffalo, New York 14260, United States.
J Nat Prod. 2018 Jan 26;81(1):72-77. doi: 10.1021/acs.jnatprod.7b00652. Epub 2018 Jan 17.
Diazofluorene compounds such as kinamycin and lomaiviticin feature unique molecular structures and compelling medicinal bioactivities. However, a complete understanding of the biosynthetic details for this family of natural products has yet to be fully elucidated. In addition, a lack of genetically and technically amenable production hosts has limited access to the full medicinal potential of these compounds. Here, we report the capture of the complete kinamycin gene cluster from Streptomyces galtieri Sgt26 by bacterial artificial chromosome cloning, confirmed by successful production of kinamycin in the heterologous host Streptomyces albus J1074. Sequence analysis and a series of gene deletion experiments revealed the boundary of the cluster, which spans 75 kb DNA. To probe the last step in biosynthesis, acetylation of kinamcyin F to kinamycin D, gene knockout, and complementation experiments identified a single gene product involved with final acetylation conversions. This study provides full genetic information for the kinamycin gene cluster from S. galtieri Sgt26 and establishes heterologous biosynthesis as a production platform for continued mechanistic assessment of compound formation and utilization.
二氮芴类化合物，如金霉素和洛马维丁，具有独特的分子结构和引人注目的药用生物活性。然而，对于这一系列天然产物的生物合成细节还没有完全阐明。此外，缺乏具有遗传和技术优势的生产宿主，限制了这些化合物充分发挥药用潜力。在这里，我们通过细菌人工染色体克隆从链霉菌 Sgt26 中捕获了完整的金霉素基因簇，并通过在异源宿主白色链霉菌 J1074 中成功生产金霉素得到了证实。序列分析和一系列基因缺失实验揭示了该基因簇的边界，跨越了 75kb 的 DNA。为了探究生物合成的最后一步，即金霉素 F 到金霉素 D 的乙酰化，基因敲除和互补实验确定了一个单一的基因产物参与了最终的乙酰化转化。这项研究提供了来自 S. galtieri Sgt26 的金霉素基因簇的完整遗传信息，并建立了异源生物合成作为一个生产平台，用于继续评估化合物形成和利用的机制。
