Chang J Y, Ngai P K, Rink H, Dennis S, Schlaeppi J M
Pharmaceuticals Research Laboratories, Ciba-Geigy Ltd., Basel, Switzerland.
FEBS Lett. 1990 Feb 26;261(2):287-90. doi: 10.1016/0014-5793(90)80573-2.
Six lysyl residues of human thrombin (LysB21, LysB52, LysB65, LysB106, LysB107 and LysB154) have been previously shown to participate in the binding site of hirudin, a thrombin-specific inhibitor [(1989) J. Biol. Chem. 264, 7141-7146]. In this report, we attempted to delineate the region of hirudin which binds to these basic amino acids of thrombin. Using the N-terminal core domains (r-Hir1-43 and r-Hir1-52) derived from recombinant hirudins and synthetic C-terminal peptides (Hir40-65 and Hir52-65)--all fragments form complexes with thrombin--we are able to demonstrate that the structural elements of hirudin which account for the shielding of these 6 lysyl residues are exclusively located within the acidic C-terminal region. Since hirudin C-terminal peptides were shown to bind to a non-catalytic site of thrombin and inhibit its interaction with fibrinogen [(1987) FEBS Lett. 211, 10-16], our data consequently imply that these 6 lysyl residues are constituents of the fibrinogen recognition site of thrombin.
人凝血酶的六个赖氨酸残基（LysB21、LysB52、LysB65、LysB106、LysB107和LysB154）先前已被证明参与凝血酶特异性抑制剂水蛭素的结合位点[(1989)《生物化学杂志》264, 7141 - 7146]。在本报告中，我们试图描绘水蛭素与凝血酶这些碱性氨基酸结合的区域。使用源自重组水蛭素的N端核心结构域（r - Hir1 - 43和r - Hir1 - 52）以及合成的C端肽（Hir40 - 65和Hir52 - 65）——所有片段均与凝血酶形成复合物——我们能够证明，水蛭素中负责屏蔽这6个赖氨酸残基的结构元件仅位于酸性C端区域。由于水蛭素C端肽已被证明可与凝血酶的一个非催化位点结合并抑制其与纤维蛋白原的相互作用[(1987)《欧洲生物化学学会联合会快报》211, 10 - 16]，因此我们的数据表明这6个赖氨酸残基是凝血酶纤维蛋白原识别位点的组成部分。
