基于宏基因组分析冬虫夏草不同发育时期的微生物多样性

Analysis on Microbiological Diversity of Cordyceps sinensis in Different Growth Stages Based on Metagenomic

目的:探究冬虫夏草不同发育期的微生物组成与多样性,挖掘影响冬虫夏草形成的关键菌群,了解主要菌群的代谢通路及其主要活性成分的功能基因。方法:以蝠蛾幼虫、僵虫、冬虫夏草为研究对象,进行宏基因组测序分析。结果:从蝠蛾幼虫、僵虫、冬虫夏草中共鉴定出4184种微生物,其中细菌在三个发育时期分别占25.62%、22.45%、14.35%,真菌分别占7.86%、12.94%、38.85%。僵虫与蝠蛾幼虫相比,冬虫夏草菌Ophiocordyceps sinensis、明尼苏达被毛孢Hirsutella minnesotensis等真菌数量有所提高,鞘脂杆菌Sphingobacteria sp.、沃尔巴克氏菌Wolbachia sp.等细菌数量有所下降。冬虫夏草与蝠蛾幼虫相比,冬虫夏草菌Ophiocordyceps sinensis、麦角菌Claviceps purpurea和明尼苏达被毛孢Hirsutella minnesotensis等真菌数量大幅增加。致病菌分析发现僵虫和冬虫夏草中绿脓杆菌Pseudomonas aeruginosa数量较蝠蛾幼虫明显增加。代谢通路分析发现三者的碳水化合物代谢活动均较突出,果糖-甘露糖代谢途径和嘌呤代谢途径分别合成虫草酸和腺苷,合成两种活性成分的关键酶分别为L-艾杜糖醇-2-脱氢酶和腺苷酸(基)琥珀酸裂解酶,其功能基因分别为CCM_05393和Plim_3831。结论:本研究有助于解析冬虫夏草发育形成的菌群组成和结构,为冬虫夏草的可持续开发利用奠定基础。

Objective:To study the microbial composition and diversity of Cordyceps sinensis in different growth stages,and to explore the key microflora affecting the formation of Cordyceps sinensis,the metabolic pathways of the key microflora and the functional genes of the main active ingredients.Methods:Hepialus larvae,stiff worm and Cordyceps sinensis were used to conduct metagenomic sequencing analysis.Results:A total of 4184 microorganism species were identified from Hepialus larvae,stiff worm and Cordyceps sinensis.Among these,the bacteria in three different development stages of Cordyceps sinensis accounted for 25.62%,22.45%,14.35%,respectively and fungi accounted for 7.86%,12.94%,38.85%,respectively.Compared to Hepialus larvae,Ophiocordyceps sinensis and Hirsutella minnesotensis in stiff worm increased significantly,Sphingobacteria sp.and Wolbachia sp.decreased.Compared to Hepialus larvae,Ophiocordyceps sinensis,Claviceps purpurea and Hirsutella minnesotensis increased significantly in Cordyceps sinensis.The analysis of pathogenic bacteria found that the number of Pseudomonas aeruginosa in stiff worm and Cordyceps sinensis was significantly higher than that in Hepialus larvae.The metabolic pathways analysis showed that carbohydrate metabolism was prominent.The fructose-mannose metabolic pathway and purine metabolic pathway synthesized D-mannitol and adenosine,respectively.L-edulitol-2-dehydrogenase and adenylate succinate lyase were the key enzymes for the synthesis of the two active ingredients,and their functional genes were CCM_05393 and Plim_3831,respectively.Conclusion:This study is conducive to analyze the bacterial colony composition and structure of growth of Cordyceps sinensis,and lay the foundation for its sustainable development and utilization.