Strauch Eva-Maria, Bernard Steffen M, La David, Bohn Alan J, Lee Peter S, Anderson Caitlin E, Nieusma Travis, Holstein Carly A, Garcia Natalie K, Hooper Kathryn A, Ravichandran Rashmi, Nelson Jorgen W, Sheffler William, Bloom Jesse D, Lee Kelly K, Ward Andrew B, Yager Paul, Fuller Deborah H, Wilson Ian A, Baker David
Department of Biochemistry, University of Washington, Seattle, Washington, USA.
Institute for Protein Design, Department of Biochemistry, University of Washington, Seattle, Washington, USA.
Nat Biotechnol. 2017 Jul;35(7):667-671. doi: 10.1038/nbt.3907. Epub 2017 Jun 12.
Many viral surface glycoproteins and cell surface receptors are homo-oligomers, and thus can potentially be targeted by geometrically matched homo-oligomers that engage all subunits simultaneously to attain high avidity and/or lock subunits together. The adaptive immune system cannot generally employ this strategy since the individual antibody binding sites are not arranged with appropriate geometry to simultaneously engage multiple sites in a single target homo-oligomer. We describe a general strategy for the computational design of homo-oligomeric protein assemblies with binding functionality precisely matched to homo-oligomeric target sites. In the first step, a small protein is designed that binds a single site on the target. In the second step, the designed protein is assembled into a homo-oligomer such that the designed binding sites are aligned with the target sites. We use this approach to design high-avidity trimeric proteins that bind influenza A hemagglutinin (HA) at its conserved receptor binding site. The designed trimers can both capture and detect HA in a paper-based diagnostic format, neutralizes influenza in cell culture, and completely protects mice when given as a single dose 24 h before or after challenge with influenza.
许多病毒表面糖蛋白和细胞表面受体都是同型寡聚体，因此有可能被几何形状匹配的同型寡聚体靶向，这些同型寡聚体可同时与所有亚基结合，以实现高亲和力和/或将亚基锁定在一起。适应性免疫系统通常无法采用这种策略，因为单个抗体结合位点的排列几何形状不合适，无法同时与单个靶同型寡聚体中的多个位点结合。我们描述了一种计算设计同型寡聚体蛋白组装体的通用策略，其结合功能与同型寡聚体靶位点精确匹配。第一步，设计一种能结合靶标上单个位点的小蛋白。第二步，将设计好的蛋白组装成同型寡聚体，使设计的结合位点与靶位点对齐。我们用这种方法设计了高亲和力的三聚体蛋白，它们能在甲型流感血凝素（HA）的保守受体结合位点与之结合。设计的三聚体既能以纸质诊断形式捕获和检测HA，在细胞培养中中和流感病毒，又能在流感病毒攻击前或攻击后24小时单剂量给药时完全保护小鼠。
