Thrombosis and/or disseminated intravascular coagulation (DIC) are complications specifically associated with the use of factor IX complex in some patients. Assuming that these complications might result from zymogen overload, we have produced, using diethylaminoethyl (DEAE)-Sephadex (Pharmacia, Piscataway, NJ) and sulfated dextran chromatography, a factor IX concentrate (coagulation factor IX) that is essentially free of prothrombin, factor VII, and factor X. Factor IX specific activity is at least 5 U/mg protein, a 250-fold purification compared to plasma.
View Article and Find Full Text PDF7F0 ---- 5D0 excitation spectroscopy of Eu(III) has shown that human Factor Xa has two high affinity lanthanide ion-binding sites. The deuterium isotope effect on the reciprocal lifetime (tau-1) of excited Eu(III) in human Factor Xa has indicated that 2 to 3 water molecules remain on Eu(III) after being complexed by Factor Xa, suggesting that 3-6 ligand atoms are provided by the protein, probably through two or three gamma-carboxyglutamic acids (GLA). F orster -type interlanthanide energy transfer has been utilized to measure the distance between the high affinity metal ion-binding sites of human Factor Xa using Tb(III) as an energy donor and Nd(III), Ho(III), or Er(III) as energy acceptors.
View Article and Find Full Text PDF7F0 leads to 5D0 excitation spectroscopy of Eu(III) has been used to investigate the Eu(III) and phospholipid binding properties of human prothrombin. The results indicate that human prothrombin contains four high-affinity Eu(III) binding sites which are distributed into two classes of binding sites. When 4 equiv of Eu(III) is bound to prothrombin, the prothrombin is capable of binding to phospholipid vesicles.
View Article and Find Full Text PDFArch Biochem Biophys
June 1980
Steady state kinetic studies have been performed to investigate the formation of thrombin from prothrombin by human coagulation Factor Xa in the presence of Ca2+ and phospholipid. The concentration of ligand which gives 50% of the maximum velocity (K0.5) is 2.
View Article and Find Full Text PDFGlutathione reductase (NAD(P)h:oxidized glutathione oxidoreductase, EC 1.6.4.
View Article and Find Full Text PDFThe effect of Ca2+, Mg2+, and Mn2+ on the initial rate of activation of human Factor X by the venom coagulant protein of Vipera russelli has been investigated. Neither Mg2+ nor Mn2+ alone support the reaction. Ca2+ is an essential activator and exhibits cooperative kinetics.
View Article and Find Full Text PDFBiochim Biophys Acta
August 1977
A rapid and specific assay has been developed for UDPglucose-collagen glucosyltransferase (UDPglucose: 5-hydroxylysine-collagen glucosyltransferase, EC 2.4.1.
View Article and Find Full Text PDFBiochemistry
October 1975
A method of determining the initial rate of plasminogen activation has been developed. The method has been used to investigate the mechanism of activation of human plasminogen by streptokinase. Plasmin formation follows saturation kinetics.
View Article and Find Full Text PDFBiochem Biophys Res Commun
July 1972