膜杰作
Star Staining
分子别名（Synonym）
S1 protein NTD,Spike protein S1 NTD,BetaCoV S1-NTD
表达区间及表达系统（Source）
Biotinylated SARS-CoV-2 S1 protein NTD, His,Avitag (S1D-C52E2) is expressed from human 293 cells (HEK293). It contains AA Val 16 - Phe 318 (Accession # QHD43416.1).
Predicted N-terminus: Val 16
Request for sequence
蛋白结构（Molecular Characterization）
This protein carries a polyhistidine tag at the C-terminus, followed by an Avi tag (Avitag™).
The protein has a calculated MW of 38.0 kDa. The protein migrates as 53-90 kDa under reducing (R) condition (SDS-PAGE) due to glycosylation.
标记（Labeling）
Biotinylation of this product is performed using Avitag™ technology. Briefly, the single lysine residue in the Avitag is enzymatically labeled with biotin.
蛋白标记度（Protein Ratio）
Passed as determined by the HABA assay / binding ELISA.
内毒素（Endotoxin）
Less than 1.0 EU per μg by the LAL method.
纯度（Purity）
>90% as determined by SDS-PAGE.
>90% as determined by SEC-MALS.
制剂（Formulation）
Lyophilized from 0.22 μm filtered solution in PBS, pH7.4 with trehalose as protectant.
Contact us for customized product form or formulation.
重构方法（Reconstitution）
Please see Certificate of Analysis for specific instructions.
For best performance, we strongly recommend you to follow the reconstitution protocol provided in the CoA.
存储（Storage）
For long term storage, the product should be stored at lyophilized state at -20°C or lower.
Please avoid repeated freeze-thaw cycles.
This product is stable after storage at:
- -20°C to -70°C for 12 months in lyophilized state;
- -70°C for 3 months under sterile conditions after reconstitution.
电泳（SDS-PAGE）
Biotinylated SARS-CoV-2 S1 protein NTD, His,Avitag on SDS-PAGE under reducing (R) condition. The gel was stained with Coomassie Blue. The purity of the protein is greater than 90%.
SEC-MALS
The purity of Biotinylated SARS-CoV-2 S1 protein NTD, His,Avitag (Cat. No. S1D-C52E2) is more than 90% and the molecular weight of this protein is around 55-76 kDa verified by SEC-MALS.
Report
活性（Bioactivity）-ELISA
Immobilized Anti-SARS-CoV-2 Spike NTD Antibody, Chimeric mAb (Cat. No. SPD-M121) at 1 μg/mL (100 μL/well) can bind Biotinylated S1 protein NTD, His,Avitag (Cat. No. S1D-C52E2) with a linear range of 1-25 ng/mL (QC tested).
Protocol
背景（Background）
It's been reported that Coronavirus 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.
