Characterization of ordered aggregates of cerato-platanin and their involvement in fungus-host interactions
Characterization of ordered aggregates of cerato-platanin and their involvement in fungus-host interactions
复制标题
DOI：
10.1016/j.bbagen.2009.07.014
复制
发表时间：
2009-10-01
影响因子：
3
通讯作者：
Cappugi, Gianni
中科院分区：
文献类型：
--
作者：
Pazzagli, Luigia;Zoppi, Camilla;Cappugi, Gianni
背景：“角藻-铂蛋白家族”由真菌分泌的蛋白组成，参与宿主-真菌相互作用的各个阶段，并作为植物毒素、防御反应的激发子和过敏原。角藻-铂蛋白（Cerato-platanin， CP）是一种中等疏水性蛋白，分泌并定位于platani角藻囊虫的细胞壁，是Platanus严重疾病的病因。这些特性使CP与疏水蛋白相似：疏水蛋白是一种自组装蛋白质，形成一层表面涂层，参与气生菌丝的形成并粘附在表面上。方法：采用ThT、圆二色性、AFM检测CP聚集。测定了CP聚集体在叶片和细胞上的诱导活性。结果：CP通过有核生长机制自组装形成淀粉样聚集体，该机制与n端断裂相结合。卵形形状和缺乏向全β结构的明确过渡将这些聚集体与典型的淀粉样原纤维区分开来。此外，CP聚集体与疏水表面相互作用，增强了Platanus的超敏反应。结论和一般意义：CP形成“有序聚集体”，其中可溶的原纤维结构是聚集过程的终点，而不会进化成不可溶的原纤维。还建议参与宿主-微生物相互作用。(C) 2009 Elsevier B.V.版权所有
Background: The "cerato-platanin family" consists of fungal-secreted proteins that are involved in various stages of the host-fungus interaction and act as phytotoxins, elicitors of defense responses and allergens. Cerato-platanin (CP) is a moderately hydrophobic protein secreted and localized in the cell wall of Cerato-cystis platani, the causal agent of a severe disease of Platanus. These properties make CP like the hydrophobins: these are self-assembling proteins that form a surface coating which is involved in the formation of aerial hyphae and in adherence to surfaces.Methods: CP aggregation was monitored by ThT, circular dichroism, and AFM. The eliciting activity of CP aggregates was assayed on leaves and cells.Results: The CP self-assembles forming amyloid-like aggregates via a nucleated growth mechanism which is joined up with a cleavage of the N-terminus. The ovoidal shape and the lack of a clear transition toward an all-beta structure distinguish these aggregates from typical amyloid fibrils. Moreover, CP aggregates interact with hydrophobic surfaces and enhance the hypersensitive response of Platanus.Conclusion and general significance: CP forms "ordered aggregates" for which the soluble prefibrillar structures are the end point of the aggregation process, and do not evolve to insoluble fibrils. An involvement in host-microbe interaction is also suggested. (C) 2009 Elsevier B.V. All rights reserved.