通过γ-羧基谷氨酸残基的化学修饰使人体血液凝固因子X失活。

Inactivation of human blood coagulation factor X by chemical modification of gamma-carboxyglutamic acid residues.

作者信息

Sherrill G B, Straight D L, Hiskey R G, Roberts H R, Griffith M J

出版信息

Biochem Biophys Res Commun. 1984 Oct 15;124(1):256-61. doi: 10.1016/0006-291x(84)90945-8.

Abstract

The inactivation of human factor X by incubation with a reagent known to chemically modify gamma-carboxyglutamic acid to gamma-methylene glutamic acid was studied. Incubation of factor X at pH 5.0 with a preincubated formaldehyde/morpholine mixture (0.9 M/1.0 M) resulted in a progressive decrease in factor X coagulant activity. In the presence of calcium (20 mM) the rate of factor X inactivation was decreased -3-fold. By using [14]C-formaldehyde, modified-factor X (less than 5% residual activity) was found to contain 7 mols of [14]C per mol of protein. Modified-factor X was not activated by Russell's viper venom in the presence of calcium, suggesting that the loss of coagulant activity was related to the inability of modified-factor X to be activated.

摘要

研究了通过与一种已知能将γ-羧基谷氨酸化学修饰为γ-亚甲基谷氨酸的试剂孵育来使人类凝血因子X失活的情况。在pH 5.0条件下，将凝血因子X与预孵育的甲醛/吗啉混合物（0.9 M/1.0 M）一起孵育，导致凝血因子X的凝血活性逐渐降低。在存在钙（20 mM）的情况下，凝血因子X失活的速率降低了3倍。通过使用[14]C-甲醛，发现修饰后的凝血因子X（残余活性小于5%）每摩尔蛋白质含有7摩尔[14]C。在有钙存在的情况下，修饰后的凝血因子X不能被罗素蝰蛇毒激活，这表明凝血活性的丧失与修饰后的凝血因子X无法被激活有关。