RAPID: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)-Prevention: Multiple-Site Binding with Fusing Aptamers to mitigate Coronavirus Disease 2019

SARS-CoV-2导致2019年新型冠状病毒传染病（COVID-19）。病毒刺突蛋白与受体蛋白（称为血管紧张素转换酶2或ACE 2）的结合是感染人类宿主细胞的第一步。阻断或抑制这种相互作用可以阻止这种高感染性病毒入侵人类细胞。有了这个奖项，生命过程的化学计划正在支持俄亥俄州Bowling绿色的Bowling绿色大学的Xiaohong Tan博士的研究，以创建DNA适体来抑制病毒入侵的这一初始步骤。适体是DNA的短序列，其折叠成与靶分子相匹配的形状，从而防止其他分子结合。这些DNA适体是通过从大量不同序列的混合物中连续选择分子来"设计"的，从而产生一些序列，这些序列阻止所有其他DNA结合靶标。Tan博士使用这种选择过程来寻找与SARS-CoV-2刺突蛋白紧密结合的DNA适体。两个或两个以上的已鉴定的DNA适体连接在一起，形成"超级结合剂"，比任何单一的适体更能抑制相互作用。构建DNA适体，阻止SARS-CoV-2入侵人类细胞，可能会导致抗病毒药物的设计，有助于减少导致COVID-19大流行的传染性。 教育和培训活动将侧重于博士后研究人员学习化学生物学前沿技术，以解决"前线"研究问题。该团队正在开发利用远程学习技术向公众、K-12机构和其他研究小组传播他们的科学的方法。该项目的目标是开发与SARS-CoV-2的结合结构域显著相互作用的聚合分子（融合DNA适体）。其目的是有效阻断病毒与特异性ACE2受体结合，从而阻断病毒进入人体细胞，从而阻断其引起COVID-19感染的能力。 Tan教授使用SELEX（通过指数富集的配体系统进化）来识别与SARS-CoV-2的刺突（S）蛋白的细胞结合结构域上的三个不同区域相互作用的单个适体。通过标准结合测定来测量适体对其靶标的亲和力。使用核酸或化学接头将这些单独的高亲和力DNA适体连接在一起，以制备具有与抗体相当的亲和力的融合适体。这些融合的DNA适体"超级粘合剂"有效阻断这种相互作用的能力是通过标准技术对重组SARS-CoV-2刺突蛋白进行测试的，以及通过与托莱多大学医学院合作对活的SARS-CoV-2进行测试的。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The SARS-CoV-2 causes the novel coronavirus infectious disease 2019 (COVID-19). The binding of the viral spike protein to a receptor protein (called the angiotensin converting enzyme 2, or ACE2) is the first step in the infection of the human host cell. Blocking or inhibiting this interaction could stop the invasion of the human cell by this highly infectious virus. With this award, the Chemistry of Life Processes program is supporting the research of Dr. Xiaohong Tan at Bowling Green University in Bowling Green, Ohio to create DNA aptamers to inhibit this initial step of viral invasion. Aptamers are short sequences of DNA that fold into a shape that matches that of a target molecule, thereby keeping other molecules from binding. These DNA aptamers are “designed” by successive selection of molecules from large mixtures of different sequences, resulting in a few sequences that keep all other DNAs from binding the target. Dr. Tan uses this selection process to find DNA aptamers that bind tightly to the SARS-CoV-2 spike protein. Two of more of the identified DNA aptamers are linked together to create “super binders” that are much better at inhibiting the interaction than would any single aptamer. Constructing DNA aptamers that block the invasion of SARS-CoV-2 into human cells may lead to the design of antiviral agents that help lessen the infectivity that causes the COVID-19 pandemic. Educational and training activities will focus on postdoctoral researchers learning cutting edge techniques in chemical biology on a “front line” research problem. The team is developing ways to communicate their science to the public, to K-12 institutions, and to other research groups using distance learning technologies.The goal of this project is to develop polymeric molecules (fusion DNA aptamers) that significantly interact with the binding domain of SARS-CoV-2. The objective is to effectively block the virus from binding to the specific ACE2 receptor, thereby blocking the entry of the virus into human cells and, as a result, its ability to cause COVID-19 infections. Professor Tan uses SELEX (systematic evolution of ligands by exponential enrichment) to identify individual aptamers that interact with three distinct regions on the cell binding domain of the spike (S) protein of SARS-CoV-2. The affinities of aptamers to their targets are measured through standard binding assays. These individual high affinity DNA aptamers are connected together using nucleic acid or chemical linkers to make fusion aptamers that have affinities comparable to those of antibodies. The ability of these fused DNA aptamer “super binders” to effectively block this interaction is tested against a recombinant SARS-CoV-2 spike protein using standard technologies, as well as live SARS-CoV-2 through collaboration with the University of Toledo Medical School.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.