Mertens K, Cupers R, Van Wijngaarden A, Bertina R M
Biochem J. 1984 Nov 1;223(3):599-605. doi: 10.1042/bj2230599.
A simple centrifugation technique has been developed to study the interaction of human coagulation Factors IXa and X with phospholipid membranes. In the presence of Ca2+, equimolar phosphatidylserine/phosphatidylcholine membranes form tight complexes with Factor X (KD = 2.8 X 10(-8) M); the KD is independent of the phospholipid concentration. Binding sites are available for about 2 mmol of Factor X/mol of phospholipid. Factor IXa has a slightly higher affinity for the phospholipid membrane (KD = 1.2 X 10(-8)M), and competes with Factor X for binding. The experimentally observed competition between Factor X and Factor IXa is in agreement with a model that describes the binding of two distinct ligands to a single class of independent binding sites.
已开发出一种简单的离心技术来研究人凝血因子IXa和X与磷脂膜的相互作用。在Ca2+存在的情况下,等摩尔的磷脂酰丝氨酸/磷脂酰胆碱膜与因子X形成紧密复合物(KD = 2.8×10(-8) M);KD与磷脂浓度无关。每摩尔磷脂约有2 mmol因子X的结合位点。因子IXa对磷脂膜的亲和力略高(KD = 1.2×10(-8)M),并与因子X竞争结合。实验观察到的因子X和因子IXa之间的竞争与描述两种不同配体与单一类独立结合位点结合的模型一致。