A cofactor is a chemical substance, which binds to a protein, and which is necessary for the biological activity of the latter. These proteins are often enzymes, and coFactors can be thought of as "helper molecules" aiding in biochemical transformations. Protein S is a 69 kDa-dependent vitamin K eglycoprotein synthesized by hepatocytes, endothelial cells, megakaryodytes and osteoblasts. It is a physiological inhibitor of coagulation. It acts as a cofactor of activated protein C by promoting the inactivation by proteaolysis of factors Va and VIIIa. It inhibits the activation of prothrombin and the formation of the prothrombinase complex on phospholipids as well as the activation of FX.
All proteins are accompanied by product information sheets which describe proper storage conditions. Many of our preparations are formulated in 50 % (vol/vol) glycerol/H₂O which will remain in fluid phase during storage at -20° C. This preferred method of storage yields the greatest stability while still allowing access to the stock sample without repeated thawing and freezing steps. All products which are formulated with glycerol/H₂O should be stored at -20° C. Temperatures lower than -30° C should be avoided in order to prevent a phase transition. When preparing to make a dilution of the stock sample, remove the sample from storage at -20° C and place on ice for a brief period of time (5-10 min). The sample will become less viscous and thus easier to pipe. Never allow protein solutions to remain at room temperature for excessive periods of time.
The vast majority of coFactors is pure (without additives) with > 95 % purity SDS-PAGE.
Expiration date of one year from delivery.
Delivery in large quantities.
Discount according to quantities.
