| Description : |
C4b binding protein (C4BP) regulates complement activation of the classical and lectin pathways. It binds to C4b and accelerates the dissociation of C2a from the C3/C5 convertase C4b,C2a. This inactivates the central enzyme of both pathways. It also functions as a cofactor allowing factor I to cleave and permanently inactivate C4b. C4BP has a flower shaped structure with each alpha chain radiating out from a central core. The arms are linked by disulfide bonds in the center and the ends of each arm bind C4b. Studies have shown that on surfaces densely coated with C4b, C4BP can bind up to four C4b molecules simultaneously (Rawal, N. et al. (2009)). |
| Source : |
Normal human serum (shown by certified tests to be negative for HBsAg and for antibodies to HCV, HIV-1 and HIV-II). |
| Species : |
Human |
| Form : |
Frozen liquid |
| Molecular Mass : |
540,000 Da (8 chains) |
| Purity : |
>90% by SDS-PAGE |
| Characteristic : |
C4BP (540,000 daltons) is composed of six or seven alpha chains (72,000 daltons each) and one beta chain (46,000 daltons). While this form is the most common, a small proportion of C4BP in most plasma samples has no beta chain and some has only six alpha chains. The six or seven arms are attached by disulfide bonds at their C-terminal ends as is the beta chain. Each alpha chain arm is composed of eight CCP repeat domains similar to those in factor H, CR1 and many other complement proteins. The pI of the intact C4BP depends on the allelic type of C4BP, but all are in the range between pH 6.6 and 6.8. |
| Usage : |
For research use only. Not for human or drug use. |
| Storage : |
-70°C or below. Avoid freeze/thaw. |
| Concentration : |
1.0 mg/mL (see Certificate of Analysis for actual concentration) |
| Storage Buffer : |
10 mM sodium phosphate, 145 mM NaCl, pH 7.2 |
| Preservative : |
None, 0.22 μm filtered. |
| Warning : |
Use normal precautions for handling human blood products. |
