Shi Jing, Zeng Ying Jie, Zhang Bo, Shao Fen Li, Chen Yan Chi, Xu Xiang, Sun Yang, Xu Qiang, Tan Ren Xiang, Ge Hui Ming
State Key Laboratory of Pharmaceutical Biotechnology , Institute of Functional Biomolecules , School of Life Sciences , Nanjing University , 210023 , China . Email:
State Key Laboratory Cultivation Base for TCM Quality and Efficacy , Nanjing University of Chinese Medicine , Nanjing 210023 , China.
Chem Sci. 2019 Jan 21;10(10):3042-3048. doi: 10.1039/c8sc05670f. eCollection 2019 Mar 14.
The ever-increasing bacterial genomic repositories reveal a great number of uncharacterized biosynthetic gene clusters, representing a tremendous resource for natural product discovery. Genome mining of the marine sp. NA03103 indicates the presence of an orphan nonribosomal peptide synthetase (NRPS) gene cluster (), to which there are no homologous gene clusters in the public genome databases. Heterologous expression of the gene cluster in the SBT18 strain led to the discovery of two novel cyclopeptides, ashimides A and B ( and ), with showing cytotoxic activity. In addition, we use bioinformatic analysis, gene inactivation and stable isotope labelling experiments, as well as biochemical assays, to present a coherent and novel assembly line for ashimide biosynthesis, featuring an unusual desaturation, halogenation and cyclization cascade catalyzed by a P450 monooxygenase and a FAD-dependent halogenase.
不断增加的细菌基因组库揭示了大量未被表征的生物合成基因簇，这是天然产物发现的巨大资源。对海洋菌株NA03103的基因组挖掘表明存在一个孤儿非核糖体肽合成酶（NRPS）基因簇（），在公共基因组数据库中没有与之同源的基因簇。该基因簇在SBT18菌株中的异源表达导致发现了两种新型环肽，ashiimides A和B（和），其中显示出细胞毒性活性。此外，我们使用生物信息学分析、基因失活和稳定同位素标记实验以及生化测定，提出了一种连贯且新颖的ashiimide生物合成装配线，其特征在于由P450单加氧酶和FAD依赖性卤化酶催化的不寻常的去饱和、卤化和环化级联反应
