Crystallization and preliminary crystallographic analysis of antistasin, a leech-derived inhibitor of blood coagulation factor Xa.
The salivary gland of the Mexican leech Haementeria officinalis contains a 15 kDa protein which is a potent and selective inhibitor of factor Xa. It inhibits not only blood coagulation, but also metastasis. A gene, coding for a sequence similar to published antistasin sequences, has been synthesized and expressed in Chinese hamster ovary (CHO) cells. The recombinant protein was purified and crystallized at pH 6.0, using 31% ammonium sulfate as a precipitant. The crystals diffract at least to 2.8 A. The spacegroup is I422 with a = b = 77.7 A and c = 88.4 A. The crystals contain 42% solvent and one protein molecule in the asymmetric unit. A search for heavy atom derivatives is in progress.
BIOSON Research Institute, University of Groningen, The Netherlands.
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H
Schreuder
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Arkema
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de Boer
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Kalk
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Dijkema
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Mulders
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Theunissen
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Hol
D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D003460:Crystallization; D065427:Factor Xa Inhibitors; D007447:Invertebrate Hormones / Q000737:chemistry*; D007865:Leeches; D011994:Recombinant Proteins / Q000737:chemistry; D014961:X-Ray Diffraction
D065427:Factor Xa Inhibitors; D007447:Invertebrate Hormones; D011994:Recombinant Proteins; C053155:antistasin