1株海洋来源Streptomyces sp.SCSIO 1682中那西肽(nosiheptide)的分离鉴定及其生物合成基因簇分析

Isolation of nosiheptide and identification of its biosynthetic gene cluster from the marine sediment derived Streptomyces sp.SCSIO 1682

目的对1株海洋来源的菌株SCSIO 1682进行16SrDNA分子生物学鉴定,对发酵产物中的抑菌活性化合物进行分离鉴定,并对抑菌活性化合物的生物合成基因簇进行分析。方法通过构建基于16SrDNA序列的系统发育树来进行菌株鉴定;通过有机溶剂萃取、正相和反相硅胶层析等化学分离手段对菌株SCSIO1682的次级代谢产物进行活性追踪分离纯化;运用HR-ESI-MS,1 H和13 C NMR等波谱手段对所得化合物进行结构解析;通过对菌株SCSIO 1682进行全基因组扫描测序鉴定所得化合物的生物合成基因簇。结果该菌株被鉴定为链霉菌,命名为Streptomyces sp.SCSIO 1682,所得抑菌活性化合物为那西肽(nosihetide),鉴定了那西肽的生物合成基因簇并进行生物信息学分析。结论从海洋链霉菌Streptomyces sp.SCSIO 1682中分离鉴定了那西肽,那西肽生物合成基因簇的鉴定为利用组合生物合成和合成生物学技术对那西肽进行结构改造提供了新的基因资源。

Objective To identify strain SCSIO 1682 isolated from the marine sediment;to isolate and identify the active antibacterial compound from the fermentation broth of this strain;and to identify the biosynthetic gene cluster responsible for this active antibacterial compound.Methods Strain SCSIO 1682 was identified by reconstructing aphylogenetic tree based on the 16 SrDNA sequences;the antibacterial compound was isolated and purified by organic solvent extraction,normal and reverse phases silica gel chromatography;and the structure of the purified antibacterial compound was elucidated by comprehensive HR-ESI-MS and 1 H,13 C NMR spectroscopic analyses;the biosynthetic gene cluster of the purified compound was identified by whole-genome scanning.Results Strain SCSIO 1682 was identified as Streptomyces sp.SCSIO 1682;the purified active antibacterial compound was proved to be nosiheptide;and the biosynthetic gene cluster of nosiheptide was identified and analyzed by bioinformatics approaches.Conclusion Nosiheptide was isolated from the marine sediment derived Streptomyces sp.SCSIO 1682,and identification of the nosiheptide biosynthetic gene cluster would provide new gene resources for generation of new nosiheptide derivatives using combinatorial biosynthesis.