Department of Biochemistry & Molecular Biology, Dalhousie University, Halifax, NS, Canada.
Sci Rep. 2022 Jan 10;12(1):366. doi: 10.1038/s41598-021-04223-6.
Hydrophobins are small proteins that are secreted by fungi, accumulate at interfaces, modify surface hydrophobicity, and self-assemble into large amyloid-like structures. These unusual properties make hydrophobins an attractive target for commercial applications as green emulsifiers and surface modifying agents. Hydrophobins have diverse sequences and tertiary structures, and depending on the hydrophobin, different regions of their structure have been proposed to be required for self-assembly. To provide insight into the assembly process, we determined the first crystal structure of a class I hydrophobin, SC16. Based on the crystal structure, we identified a putative intermolecular contact that may be important for rodlet assembly and was formed in part by the N-terminal tail of SC16. Surprisingly, removal of the N-terminal tail did not influence the self-assembly kinetics of SC16 or the morphology of its rodlets. These results suggest that other regions of this hydrophobin class are required for rodlet formation and indicate that the N-terminal tail of SC16 is amenable to modification so that functionalized hydrophobin assemblies can be created.
水蛋白是由真菌分泌的小蛋白，在界面处积累，改变表面疏水性，并自组装成大型类似淀粉样的结构。这些不寻常的特性使水蛋白成为有吸引力的商业应用目标，如绿色乳化剂和表面改性剂。水蛋白具有不同的序列和三级结构，并且根据水蛋白的不同，其结构的不同区域被提出是自组装所必需的。为了深入了解组装过程，我们确定了第一类水蛋白 SC16 的晶体结构。基于晶体结构，我们确定了一个可能对小杆组装很重要的假定分子间接触，该接触部分由 SC16 的 N 端尾巴形成。令人惊讶的是，去除 N 端尾巴并没有影响 SC16 的自组装动力学或其小杆的形态。这些结果表明，该水蛋白类的其他区域是小杆形成所必需的，并表明 SC16 的 N 端尾巴易于修饰，因此可以创建功能化的水蛋白组装体。
