Activation of bovine factor X (Stuart factor): conversion of factor Xaalpha to factor Xabeta.

AUTOR(ES)

Fujikawa, K

RESUMO

Bovine factor X (molecular weight 55,100) is a blood coagulation factor present in plasma in a precursor or zymogen form. It is a glycoprotein which has been isolated as a two-chain structure held together by one or more disulfide bonds. During the coagulation process, factor X is converted to a serine protease by the hydrolysis of a specific peptide bond in the amino-terminal region of the heavy chain. This cleavage occurs between Arg-51 and Ile-52, giving rise to factor Xaalpha (molecular weight 45,300) and an activation peptide (molecular weight 9500). Factor Xaalpha is then converted to factor Xabeta (molecular weight 42,600) by hydrolysis of a second specific peptide bond in the carboxyl-terminal region of the heavy chain. This cleavage occurs between Arg-290 and Gly-291, giving rise to a second glycopeptide (molecular weight 2700). Factor Xaalpha and factor Xabeta have equivalent coagulant activity, indicating that the cleavage of the second peptide bond is unrelated to the activation process.

Documentos Relacionados

• Bovine factor X1 (Stuart factor): amino-acid sequence of heavey chain.
• Bovine factor X1 (Stuart factor). Primary structure of the light chain.
• A Comparison of Bovine Prothrombin, Factor IX (Christmas Factor), and Factor X (Stuart Factor)*
• Human platelet membrane receptor for bovine von Willebrand factor (platelet aggregating factor): An integral membrane glycoprotein
• Somatomedin-like peptide(s) isolated from fetal bovine cartilage (cartilage-derived factor): isolation and some properties.