Antithrombin ‘DREUX’ (Lys114Glu): A Variant with Complete Loss of Heparin Affinity-猫眼课题宝

抗凝血酶‘DREUX’ (Lys114Glu)：完全丧失肝素亲和力的变体

DOI：

发表时间：

2002

期刊：

Thrombosis and Haemostasis

影响因子：

6.7

通讯作者：

中科院分区：

医学2区

文献类型：

作者：

A. Mushunje;Aiwu Zhou;J. Huntington;J. Conard;R. Carrell

Summary Here we report the finding of a new natural antithrombin mutation that confirms the critical contribution of lysine 114 to the binding of the core heparin pentasaccharide, with the replacement of lysine 114 by glutamate causing a complete loss in affinity. The variant was identified in a father and son, the father having been investigated for an episode of cerebral ischaemia associated with hypercholesterolaemia. The variant forms SDS-stable complexes with activated factor X (fXa) and its thermal stability and rate of factor Xa inhibition in the absence of heparin are identical to those of normal antithrombin. Normal antithrombin binds to the high affinity heparin pentasaccharide with a Kd of 1nM, as detected by a 45% change in intrinsic fluorescence, resulting in a 230-fold increase in rate of factor Xa inhibition. However, no change in fluorescence was detected for the variant when titrated with heparin or the heparin pentasaccharide, nor was there detectable activation towards factor Xa, indicating a complete loss of heparin binding.