美国华盛顿大学David Baker和英国剑桥大学MRC分子生物学实验室Emmanuel Derivery团队合作研发出具有生物活性的二元蛋白质二级结构。相关论文于2021年1月6日在线发表于《自然》杂志。
研究人员设计了一种计算方法，该方法通过设计成对二面体蛋白质构造块之间的刚性界面来共装配成二元层，并用它设计了p6m晶格。该方法生成的结构可在毫摩尔浓度下溶解，但当以纳摩尔浓度组合时，它们则快速组装成几乎与体外和细胞内计算设计模型相同的微米级结晶结构，而无需二级结构。由于该结构是从头设计的，因此可以轻松地对组件进行功能化，并重新配置它们的对称性，从而能够形成具有表面可区分的配体结构，研究证明了它们可以诱导广泛的受体簇、下游蛋白招募和信号传导。
使用原子力显微镜观察支持层和定量显微镜检测活细胞，研究人员发现在膜上组装的蛋白具有与体外形成阵列相似的化学计量和结构组成，因此该结构可以对基本无序的底物（例如细胞膜）施加顺序。先前报道的细胞表面受体结合组件（例如抗体和纳米笼）会被细胞迅速内吞，研究人员发现在细胞表面组装的大复合物其通过可调的方式抑制内吞作用，从而具有扩大受体参与和逃避免疫的潜在治疗意义。
该工作为合成细胞生物学奠定了基础，其中多蛋白质宏观结构被设计用于调节细胞反应并重塑合成和生命系统。
据介绍，合成有序的二级结构（例如S层和其类似物）吸引着合成生物学家的注意，但是除了由柔性接头形成的单个晶格之外，它们仅由一种蛋白质构成。由两个组件组成的结构具有潜在的优势，可以调节装配动力学并具有更复杂的功能。
附：英文原文
Title: Design of biologically active binary protein 2D materials
Author: Ariel J. Ben-Sasson, Joseph L. Watson, William Sheffler, Matthew Camp Johnson, Alice Bittleston, Logeshwaran Somasundaram, Justin Decarreau, Fang Jiao, Jiajun Chen, Ioanna Mela, Andrew A. Drabek, Sanchez M. Jarrett, Stephen C. Blacklow, Clemens F. Kaminski, Greg L. Hura, James J. De Yoreo, Justin M. Kollman, Hannele Ruohola-Baker, Emmanuel Derivery, David Baker
Issue&Volume: 2021-01-06
Abstract: Ordered two-dimensional arrays such as S-layers1,2 and designed analogues3,4,5 have intrigued bioengineers6,7, but with the exception of a single lattice formed with flexible linkers8, they are constituted from just one protein component. Materials composed of two components have considerable potential advantages for modulating assembly dynamics and incorporating more complex functionality9,10,11,12. Here we describe a computational method to generate co-assembling binary layers by designing rigid interfaces between pairs of dihedral protein building blocks, and use it to design a p6m lattice. The designed array components are soluble at millimolar concentrations, but when combined at nanomolar concentrations, they rapidly assemble into nearly crystalline micrometre-scale arrays nearly identical to the computational design model in vitro and in cells without the need for a two-dimensional support. Because the material is designed from the ground up, the components can be readily functionalized and their symmetry reconfigured, enabling formation of ligand arrays with distinguishable surfaces, which we demonstrate can drive extensive receptor clustering, downstream protein recruitment and signalling. Using atomic force microscopy on supported bilayers and quantitative microscopy on living cells, we show that arrays assembled on membranes have component stoichiometry and structure similar to arrays formed in vitro, and that our material can therefore impose order onto fundamentally disordered substrates such as cell membranes. In contrast to previously characterized cell surface receptor binding assemblies such as antibodies and nanocages, which are rapidly endocytosed, we find that large arrays assembled at the cell surface suppress endocytosis in a tunable manner, with potential therapeutic relevance for extending receptor engagement and immune evasion. Our work provides a foundation for a synthetic cell biology in which multi-protein macroscale materials are designed to modulate cell responses and reshape synthetic and living systems.
DOI: 10.1038/s41586-020-03120-8
Source: https://www.nature.com/articles/s41586-020-03120-8
Nature：《自然》，创刊于1869年。隶属于施普林格·自然出版集团，最新IF：69.504
官方网址：http://www.nature.com/
投稿链接：http://www.nature.com/authors/submit_manuscript.html
本期文章：《自然》：Online/在线发表
