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引起新型冠状病毒传染病2019 （COVID-19）。病毒刺突蛋白与受体蛋白（称为血管紧张素转换酶2，简称ACE2）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传染性病毒对人类细胞的入侵。凭借这一奖项，生命过程化学项目将支持俄亥俄州鲍灵格林大学谭晓红博士的研究，以创造DNA适体来抑制病毒入侵的第一步。适配体是DNA的短序列，它折叠成与目标分子相匹配的形状，从而阻止其他分子结合。这些DNA适体是通过从不同序列的大混合物中连续选择分子来“设计”的，从而产生一些序列，使所有其他DNA无法结合目标。谭博士利用这一选择过程寻找与SARS-CoV-2刺突蛋白紧密结合的DNA适体。两个或两个以上的DNA适体连接在一起，形成“超级粘合剂”，这种粘合剂比任何单一的适体都能更好地抑制相互作用。构建阻断SARS-CoV-2侵入人体细胞的DNA适体，可能会导致设计出有助于减轻导致COVID-19大流行的传染性的抗病毒药物。教育和培训活动将侧重于博士后研究人员在“前沿”研究问题上学习化学生物学的尖端技术。该团队正在开发方法，将他们的科学传播给公众、K-12机构和其他使用远程学习技术的研究团体。该项目的目标是开发与SARS-CoV-2结合域显著相互作用的聚合分子（融合DNA适体）。目标是有效阻止病毒与特定的ACE2受体结合，从而阻止病毒进入人类细胞，从而阻止其引起COVID-19感染的能力。谭教授使用SELEX（通过指数富集的配体系统进化）来识别与SARS-CoV-2刺突(S)蛋白细胞结合域上三个不同区域相互作用的单个适体。适体与靶的亲和力是通过标准的结合测定来测定的。这些单独的高亲和力DNA适体通过核酸或化学连接体连接在一起，形成与抗体具有相当亲和力的融合适体。这些融合的DNA适体“超级结合物”有效阻断这种相互作用的能力，使用标准技术针对重组SARS-CoV-2刺突蛋白进行了测试，并通过与托莱多大学医学院合作，对活的SARS-CoV-2进行了测试。该奖项反映了美国国家科学基金会的法定使命，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.