Biotinylated Human Transferrin Protein, His,Avitag™ (MALS verified)
分子别名（Synonym）
Transferrin,TF,DKFZp781D0156,PRO1557,PRO2086
表达区间及表达系统（Source）
Biotinylated Human Transferrin Protein, His,Avitag (TRN-H82E3) is expressed from human 293 cells (HEK293). It contains AA Val 20 - Pro 698 (Accession # P02787).
Predicted N-terminus: Val 20
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 78.8 kDa. The protein migrates as 70-85 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.
背景（Background）
转铁蛋白也称为血清转铁蛋白、β-1金属结合球蛋白、TF，是控制生物体液中游离铁水平的铁结合血浆糖蛋白。虽然与转铁蛋白结合的铁不到全身铁的0.1%（4mg），但它是最重要的铁库，周转率最高（25mg/24h）。转铁蛋白对Fe（III）的亲和力极高（pH 7.4时为1023 M−1），但随着pH值降至中性以下而逐渐降低。当不与铁结合时，它被称为“脱辅基转铁蛋白”。在人类中，转铁蛋白由一条含有679个氨基酸的多肽链组成。它是一个由α螺旋和β折叠组成的复合物，形成两个结构域（第一个位于N端，第二个位于C端）N端和C端序列由球形裂片表示，两个裂片之间有一个铁结合位点。肝脏是制造转铁蛋白的主要来源，但大脑等其他来源也会产生这种分子。转铁蛋白也与先天免疫系统有关。转铁蛋白存在于粘膜中并与铁结合，从而创造了一个游离铁含量低的环境，阻碍了细菌在铁抑制过程中的存活。炎症时转铁蛋白水平降低。转铁蛋白的金属结合特性对人体钚的生物化学有很大影响。转铁蛋白对细菌具有杀菌作用，因为它使细菌无法获得Fe3+。碳水化合物缺乏的转铁蛋白随着大量乙醇的消耗而在血液中增加，可以通过实验室检测进行监测。
