膜杰作
Star Staining
分子别名（Synonym）
CD55,DAF,CR,CROM,TC
表达区间及表达系统（Source）
Human CD55, His Tag (CD5-H5225) is expressed from human 293 cells (HEK293). It contains AA Asp 35 - Ser 353 (Accession # NP_000565.1).
Predicted N-terminus: Asp 35
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 35.8 kDa. The protein migrates as 50-65 kDa under reducing (R) condition (SDS-PAGE) due to glycosylation.
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. Normally trehalose is added as protectant before lyophilization.
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）
Human CD55, 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%.
文献引用（Citations）
Authors: Kwon YC, et al.
Journal: J Immunol 2016
Application: CDC assay
背景（Background）
CD55 is also known as DAF or decayaccelerating factor, is a member of the RCA (regulators of complement activation) family characterized by four to 30 SCRs (short consensus repeats) in their plasma-exposed regions. CD55 /DAF is a 70 kDa membrane protein that regulates the complement system on the cell surface. It prevents the assembly of the C3bBb complex (the C3-convertase of the alternative pathway) or accelerates the disassembly of preformed convertase, thus blocking the formation of the membrane attack complex. This glycoprotein is broadly distributed among hematopoietic and non-hematopoietic cells. It is a determinant for the Cromer blood group system. CD55 is known to bind CD97 via the first SCR. It also binds physiologicallygenerated C3 convertases with its second and third SCRs. Binding results in an accelerated “decay”, or dissociation of active C3 convertases, thus blocking the development of C’ attack complexes on nonforeign cells. Finally, viruses and bacteria are also known to utilize multiple SCR sites for infection.
