膜杰作
Star Staining
分子别名（Synonym）
Streptavidin,SA
表达区间及表达系统（Source）
Streptavidin (A24C) Protein, His Tag (STN-N51H3) is expressed from E. coli cells. It contains AA Cys 24 - Gln 183 (Accession # P22629-1 (A24C)).
Predicted N-terminus: Met
Request for sequence
蛋白结构（Molecular Characterization）
This protein carries a polyhistidine tag at the C-terminus.
The protein has a calculated MW of 18.6 kDa. The protein migrates as 19-20 kDa when calibrated against Star Ribbon Pre-stained Protein Marker under reducing (R) condition (SDS-PAGE).
内毒素（Endotoxin）
Less than 1.0 EU per μg by the LAL method.
纯度（Purity）
>95% as determined by SDS-PAGE.
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）
Streptavidin (A24C) Protein, His Tag on SDS-PAGE under reducing (R) condition. The gel was stained with Coomassie Blue. The purity of the protein is greater than 95% (With Star Ribbon Pre-stained Protein Marker).
活性（Bioactivity）-ELISA
Immobilized Biotinylated Human Dkk-1, Fc,Avitag (Cat. No. DK1-H82F5) at 5 μg/mL (100 μL/well) on Streptavidin (A24C) Protein, His Tag (Cat. No. STN-N51H3) precoated (0.5 μg/well) plate can bind Human LRP-5, Mouse IgG2a Fc Tag (Cat. No. LR5-H5254) with a linear range of 0.5-16 ng/mL (QC tested).
Protocol
背景（Background）
Streptavidin is a 66KDa tetrameric protein purified from the bacterium Streptomyces avidinii, and exhibits high binding affinity to biotin. Each unit can bind one biotin. Horseradish peroxidase is metalloenzyme, a 44KDa glycoprotein. When incubate with substrates, it produces a coloured, fluorimetric, or luminescent derivatives, which can be detected and quantified. HRP conjugated Streptavidin is widely used for the detection and quantification of biotinylated proteins.
