The conidial mucilage, natural film coatings, is involved in environmental adaptability and pathogenicity of Hirsutella satumaensis Aoki.
The conidial mucilage, natural film coatings, is involved in environmental adaptability and pathogenicity of Hirsutella satumaensis Aoki.
复制标题
分生孢子粘液，天然薄膜包衣，与萨图马被毛孢青木的环境适应性和致病性有关
DOI：
10.1038/s41598-017-01368-1
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发表时间：
2017-05-02
影响因子：
4.6
通讯作者：
Zhou Y
中科院分区：
文献类型：
--
作者：
Qu J;Zou X;Yu J;Zhou Y
毛菌属是一种非常特殊的无性繁殖的昆虫病原体，它具有孢子减少、寄主特异性和孢子被厚厚的粘液层覆盖的特点。然而，分生孢子粘液的生态功能尚不清楚。本研究通过对气生分生孢子（AC）和无粘液分生孢子（MFC）的耐受性、粘附性和昆虫生物测定，对昆虫病原真菌satumaensis毛癣菌（Hirsutella satumaensis）分生孢子粘液可能的生态作用进行了功能研究。利用微生物对碳氢化合物的黏附（MATH）测定疏水性表明，粘液是AC表面疏水性的主要因素。在极端温度、高压、长时间暴露于紫外线辐射和冷胁迫下，AC比MFC产生更多的菌落，表现出更高的分生率和发芽率。在粘附试验中，当用0.05%的Tween 20洗涤时，MFC对蝗虫，蜻蜓角质层和洋葱表皮的粘附性降低了约40%。同样，产胶AC感染的青虫廊虫和小菜蛾幼虫死亡率也相对较高。我们的研究结果表明，黏液对红木的生态适应性至关重要，它在维持孢子表面疏水性、增强孢子对极端环境的抵抗力、增强孢子粘附力和宿主致病性等方面发挥着积极作用。
The Hirsutella genus is very special asexually-reproducing pathogens of insects by reduced sporulation, host specificity and spores covered by a thick mucilage layer. However, the ecological function of conidial mucilage remains elusive. In this study, the possible ecological role of conidial mucilage from the entomopathogenic fungus Hirsutella satumaensis was functionally investigated through tolerance, adherence and insect bioassays involving aerial conidia (AC) and mucilage-free conidia (MFC). Measurements of hydrophobicity using microbial adhesion to hydrocarbons (MATH) indicated that mucilage is main contributor to the surface hydrophobicity of AC. When subjected in tolerance assays to extreme temperatures, high chemical pressure, extended exposure to ultraviolet radiation and cold stress, AC produced more colonies, exhibited higher conidiation and germination percentages than those of MFC. In adhesion assays, MFC displayed an approximately 40% reduction in adherence to locust, dragonfly cuticle and onion epidermis when washed with 0.05% Tween 20. Similarly, Galleria mellonella and Plutella xylostella larvae infected with mucilage-producing AC experienced a relatively higher mortality rate. Our findings suggest that mucilage is critical to the ecological adaptability of H. satumaensis, where it plays positive roles on maintenance of spore surface hydrophobicity, enhancement of spore resistance to extreme environments and strengthening of spore adhesion and host pathogenicity.