Quorum Sensing Activity and Hyphal Growth by External Stimuli in the Entomopathogenic Fungus Ophiocordyceps sinensis
Quorum Sensing Activity and Hyphal Growth by External Stimuli in the Entomopathogenic Fungus Ophiocordyceps sinensis
复制标题
昆虫病原真菌冬虫夏草的群体感应活性和外部刺激下的菌丝生长
DOI：
10.3390/insects11040205
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发表时间：
2020-04-01
期刊：
影响因子：
3
通讯作者：
Han, Richou
中科院分区：
文献类型：
--
作者：
Liu, Guiqing;Cao, Li;Han, Richou
昆虫病原真菌虫草是中国最著名、最珍贵的药物和保健食品之一。这种真菌在宿主血淋巴中的胚孢子-菌丝（二态）转变对宿主幼虫的毒力和木乃伊化至关重要。为了调节这一转变，在体外研究了接种量和15种化学物质（包括真菌营养物质、真菌代谢物、群体感应分子（QSMs）和昆虫激素）对中华金银花二态性的影响。当接种浓度为107个/ mL时，芽孢萌发，当浓度低于106个/ mL时，菌丝萌发。当接种浓度为105个/ mL时，菌丝形成率随着添加含有107个/ mL的滤过的废培养基而降低，说明存在群体感应效应。在15种化学物质作用下，该真菌的芽孢-菌丝转变从无反应到二态恢复不等。三种浓度的n -乙酰氨基葡萄糖均能显著促进菌丝形成，抑制芽殖生长。首次发现昆虫激素20-羟基蜕皮激素参与真菌菌丝的形成。这些结果为调节二态性开辟了新的可能性，对冬虫夏草的栽培有益。
The entomopathogenic fungus Ophiocordyceps sinensis is one of the best known and most precious medicines and health food in China. The blastospores-hyphae (dimorphism) transition of this fungus in host hemolymph is critical for the virulence and the mummification of host larvae. To regulate this transition, the effects of inoculum density and fifteen chemicals including fungal nutrients, fungal metabolites, quorum-sensing molecules (QSMs) and insect hormones on the dimorphism in O. sinensis were investigated in vitro. The blastospores tended to exhibit budding growth when inoculated at 107 blastospores per mL, and hyphal growth at concentrations lower than 106 blastospores per mL. At 105 blastospores per mL, the percentage of hyphal formation decreased with the addition of filtered spent medium containing 107 blastospores per mL, indicating the quorum-sensing effect. Blastospores-hyphae transition in this fungus by fifteen chemicals was varied from no response to dimorphic reversion. The addition of N-acetylglucosamine at three concentrations significantly stimulated hyphal formation while inhibiting budding growth. For the first time, insect hormone 20-hydroxyecdysone was found to be involved in the hyphal formation in fungi. These results open new possibilities to regulate the dimorphism, which would be beneficial for the cultivation of the Chinese cordyceps.