GMA-560

Background

Bovine Factor X (Mr 55,000) is a vitamin K-dependent plasma protein zymogen that plays a central role as the substrate for both the intrinsic (factor VIIa, tissue factor) and extrinsic (factor IXa, factor VIIIa) pathways. In the presence of cofactor factor Va, phospholipid, and Ca²⁺, activated factor X cleaves two peptide bonds in prothrombin to form thrombin. GMA-560 (also known as α-BFX-2b) binds bovine FX and factor Xa in solid-phase ELISA and Western blot. GMA-560 is partially calcium-dependent, inhibits FX activity in human, bovine, porcine, rabbit, and canine plasma inhibits the conversion of prothrombin to thrombin and prevents inactivation of FXa by antithrombin III¹. It can be used in the purification of factor X from plasma^2,3 and blocks FXa-thrombomodulin interaction⁴.