期刊
JOURNAL OF MOLECULAR BIOLOGY
卷 296, 期 2, 页码 651-658出版社
ACADEMIC PRESS LTD
DOI: 10.1006/jmbi.1999.3447
关键词
streptavidin; biotin; biosensor; biacore; electrostatic steering
资金
- NHLBI NIH HHS [HL47463, HL62565] Funding Source: Medline
The rate constants for the binding interaction between thrombin and a fully active fragment of its anticoagulant cofactor, thrombomodulin, have been determined by surface plasmon resonance. At physiological ionic strength, the k(a) was 6.7 x 10(6) M-1 s(-1) and the dissociation rate constant was 0.033 s(-1). These extremely fast association and dissociation rates resulted in an overall binding equilibrium constant of 4.9 nM, which is similar to previously reported values. Changing the ionic strength from 100 mM to 250 mM NaCl caused a tenfold decrease in the association rate while the dissociation rate did not change significantly. A similar effect was observed with tetramethylammonium chloride. A Debye-Huckel plot of the data had a slope of -6 and an intercept at 0 ionic strength of 10(9) M-1 s(-1): The same slope and intercept were obtained for data that was collected in the presence of glycerol to slow the association rates. These results show that the thrombin-TM456 interaction is extremely rapid and nearly completely electrostatically steered. An association model is presented in which TM456 approaches thrombin along the direction of the thrombin molecular dipole. (C) 2000 Academic Press.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据