背景介绍 The COVID-19 pandemic is caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). The Spike glycoprotein is expressed on the surface of the virus as a trimer. Each Spike protein consists of two subunits, S1 and S2, and the S1 subunit contains the receptor binding domain (RBD) which recognizes and attaches to the ACE2 receptor found on the surface of type I and II pneumocytes, endothelial cells, and ciliated bronchial epithelial cells. SARS-CoV-2 Variant B.1.617.2, also known as Delta variant, was originally discovered in India and contains mutations L452R and T478K. Drugs targeting the interaction between SARS-CoV-2 Spike protein and human ACE2 may offer some protection against viral infection. The Spike S1 RBD (B.1.617.2; Delta Variant) (SARS-CoV-2) protein (BPS Bioscience #101153) in this kit consists of the RBD region (amino acids 319-541 with mutations L452R and T478K), which includes the ACE2 binding site. 产品介绍 The Spike S1 RBD (B.1.617.2; Delta Variant) (SARS-CoV-2): ACE2 Inhibitor Screening Colorimetric Assay Kit is designed for screening and profiling inhibitors or neutralizing antibodies of  the interaction between SARS-CoV-2 Spike and human ACE2.  The assay requires only a few steps. First, Spike S1 RBD (B.1.617.2; Delta Variant) (SARS-CoV-2) is coated on a 96-well plate overnight. After blocking, the protein is pre-incubated with the inhibitor or neutralizing antibody. Upon subsequent incubation with Biotin-ACE2, the plate is treated with Streptavidin-HRP followed by addition of a colorimetric HRP substrate to produce color, which can be quenched and measured using a UV/Vis microplate reader.