1aht
From Proteopedia
CRYSTAL STRUCTURE OF HUMAN ALPHA-THROMBIN COMPLEXED WITH HIRUGEN AND P-AMIDINOPHENYLPYRUVATE AT 1.6 ANGSTROMS RESOLUTION
Structural highlights
Disease[THRB_HUMAN] Defects in F2 are the cause of factor II deficiency (FA2D) [MIM:613679]. It is a very rare blood coagulation disorder characterized by mucocutaneous bleeding symptoms. The severity of the bleeding manifestations correlates with blood factor II levels.[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] Genetic variations in F2 may be a cause of susceptibility to ischemic stroke (ISCHSTR) [MIM:601367]; also known as cerebrovascular accident or cerebral infarction. A stroke is an acute neurologic event leading to death of neural tissue of the brain and resulting in loss of motor, sensory and/or cognitive function. Ischemic strokes, resulting from vascular occlusion, is considered to be a highly complex disease consisting of a group of heterogeneous disorders with multiple genetic and environmental risk factors.[13] Defects in F2 are the cause of thrombophilia due to thrombin defect (THPH1) [MIM:188050]. It is a multifactorial disorder of hemostasis characterized by abnormal platelet aggregation in response to various agents and recurrent thrombi formation. Note=A common genetic variation in the 3-prime untranslated region of the prothrombin gene is associated with elevated plasma prothrombin levels and an increased risk of venous thrombosis. Defects in F2 are associated with susceptibility to pregnancy loss, recurrent, type 2 (RPRGL2) [MIM:614390]. A common complication of pregnancy, resulting in spontaneous abortion before the fetus has reached viability. The term includes all miscarriages from the time of conception until 24 weeks of gestation. Recurrent pregnancy loss is defined as 3 or more consecutive spontaneous abortions.[14] Function[THRB_HUMAN] Thrombin, which cleaves bonds after Arg and Lys, converts fibrinogen to fibrin and activates factors V, VII, VIII, XIII, and, in complex with thrombomodulin, protein C. Functions in blood homeostasis, inflammation and wound healing.[15] [HIRV1_HIRME] Hirudin is a potent thrombin-specific protease inhibitor. It forms a stable non-covalent complex with alpha-thrombin, thereby abolishing its ability to cleave fibrinogen.[16] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedCrystals of human alpha-thrombin complexed with hirugen and the alpha-keto acid thrombin inhibitor APPA (p-amidinophenylpyruvate) that diffract to 1.6 A resolution were obtained by soaking an alpha-thrombin-hirugen crystal in a solution of APPA. The crystal structure was determined using the difference Fourier method and refined to an R factor of 18.7% at 1.6 A resolution. This structure is the highest resolution structure of the thrombin molecule that is currently available. With the exception of the region near Arg77A-Asn78, the structures of the thrombin and hirugen molecules in the ternary complex are similar to those reported for the thrombin-hirugen binary complex. As previously determined for the APPA-trypsin complex, the carbonyl carbon atom of APPA forms a covalent bond with O gamma of Ser195 of thrombin to yield a "transition-state" analog of the tetrahedral intermediate. Comparison of the specificity pocket of the APPA complexes of thrombin and trypsin reveals differences in hydrogen bonding and shows for the first time that the S1 site of thrombin is larger than that of trypsin and as a result thrombin may be able to accommodate a bulkier P1 group than trypsin. Crystal structure of human alpha-thrombin complexed with hirugen and p-amidinophenylpyruvate at 1.6 A resolution.,Chen Z, Li Y, Mulichak AM, Lewis SD, Shafer JA Arch Biochem Biophys. 1995 Sep 10;322(1):198-203. PMID:7574675[17] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||||||
