Changes in interactions in complexes of hirudin derivatives and human alpha-thrombin due to different crystal forms
Research article published in Protein science : a publication of the Protein Society (1993)
Abstract
The three-dimensional structures of D-Phe-Pro-Arg-chloromethyl ketone-inhibited thrombin in complex with Tyr-63-sulfated hirudin (ternary complex) and of thrombin in complex with the bifunctional inhibitor D-Phe-Pro-Arg-Pro-(Gly)4-hirudin (CGP 50,856, binary complex) have been determined by X-ray crystallography in crystal forms different from those described by Skrzypczak-Jankun et al. (Skrzypczak-Jankun, E., Carperos, V.E., Ravichandran, K.G., & Tulinsky, A., 1991, J. Mol. Biol. 221, 1379-1393). In both complexes, the interactions of the C-terminal hirudin segments of the inhibitors binding to the fibrinogen-binding exosite of thrombin are clearly established, including residues 60-64, which are disordered in the earlier crystal form. The interactions of the sulfate group of Tyr-63 in the ternary complex structure explain why natural sulfated hirudin binds with a 10-fold lower K(i) than the desulfated recombinant material. In this new crystal form, the autolysis loop of thrombin (residues 146-150), which is disordered in the earlier crystal form, is ordered due to crystal contacts. Interactions between the C-terminal fragment of hirudin and thrombin are not influenced by crystal contacts in this new crystal form, in contrast to the earlier form. In the bifunctional inhibitor-thrombin complex, the peptide bond between Arg-Pro (P1-P1') seems to be cleaved.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Resumen
The three-dimensional structures of D-Phe-Pro-Arg-chloromethyl ketone-inhibited thrombin in complex with Tyr-63-sulfated hirudin (ternary complex) and of thrombin in complex with the bifunctional inhibitor D-Phe-Pro-Arg-Pro-(Gly)4-hirudin (CGP 50,856, binary complex) have been determined by X-ray crystallography in crystal forms different from those described by Skrzypczak-Jank.
Por qué esto importa para la hirudoterapia
Este artículo reporta estructuras cristalinas de rayos X de trombina en complejo con hirudina sulfatada en Tyr-63 (complejo ternario con trombina inhibida por PPACK) y con D-Phe-Pro-Arg-Pro-(Gly)4-hirudina (CGP 50,856, complejo binario) en formas cristalinas diferentes de las estructuras previamente reportadas. El resumen aclara las interacciones de los segmentos C-terminales de la hirudina que se unen al exosito de unión al fibrinógeno (incluyendo los residuos 60–64, previamente desordenados), explica por qué la sulfatación en Tyr-63 reduce la K(i) aproximadamente 10 veces en comparación con el material recombinante desulfatado, y revela el ordenamiento del bucle de autólisis. Para ASH, esto es relevante para comprender las interacciones hirudina-trombina a nivel estructural. La advertencia es que el trabajo es puramente estructural/cristalográfico y no presenta datos funcionales, in vivo ni clínicos.
Citación
Changes in interactions in complexes of hirudin derivatives and human alpha-thrombin due to different crystal forms
Priestle JP et al. · Protein science : a publication of the Protein Society, 1993
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Añadido a la biblioteca ASH: May 27, 2026 · Última actualización del sitio: 18 de junio de 2026