Spike RBD (D364Y)(His Tag)(Active) (recombinant SARS-CoV-2)

Activity: Antigen was assessed by binding ability with ACE-2(PKSR030492) or Anti-2019-nCoV-S1 mAb(5D9). Protein Construction: Recombinant 2019-nCoV S protein RBD Protein is produced by our Mammalian expression system and the target gene encoding Arg319-Phe541(D364Y) is expressed with a 6His tag at the C-terminus. Sequence: Arg319-Phe541(D364Y). Fusion tag: C-6His Endotoxin: Not test Apparent Molecular Mass: 35kDa. Protein function: The spike (S) glycoprotein of coronaviruses is known to be essential in the binding of the virus to the host cell at the advent of the infection process. Most notable is severe acute respiratory syndrome (SARS). The severe acute respiratory syndrome-coronavirus (SARS-CoV) spike (S) glycoprotein alone can mediate the membrane fusion required for virus entry and cell fusion. It is also a major immunogen and a target for entry inhibitors. It's been reported that 2019-nCoV can infect the human respiratory epithelial cells through interaction with the human ACE2 receptor. The spike protein is a large type I transmembrane protein containing two subunits, S1 and S2. S1 mainly contains a receptor binding domain (RBD), which is responsible for recognizing the cell surface receptor. S2 contains basic elements needed for the membrane fusion.The S protein plays key parts in the induction of neutralizing-antibody and T-cell responses, as well as protective immunity.Some findings indicated that the mutated viruses may be evolved to acquire remarkably increased infectivity. Protein function: [Spike protein S1]: attaches the virion to the cell membrane by interacting with host receptor, initiating the infection. Binding to human ACE2 receptor and internalization of the virus into the endosomes of the host cell induces conformational changes in the Spike glycoprotein (PubMed:32142651, PubMed:32221306, PubMed:32075877, PubMed:32155444). Binding to host NRP1 and NRP2 via C-terminal polybasic sequence enhances virion entry into host cell (PubMed:33082294, PubMed:33082293). This interaction may explain virus tropism of human olfactory epithelium cells, which express high level of NRP1 and NRP2 but low level of ACE2 (PubMed:33082293). The stalk domain of S contains three hinges, giving the head unexpected orientational freedom (PubMed:32817270). Uses human TMPRSS2 for priming in human lung cells which is an essential step for viral entry (PubMed:32142651). Can be alternatively processed by host furin (PubMed:32362314). Proteolysis by cathepsin CTSL may unmask the fusion peptide of S2 and activate membranes fusion within endosomes. [The UniProt Consortium]