Schreuder H, Arkema A, de Boer B, Kalk K, Dijkema R, Mulders J, Theunissen H, Hol W
BIOSON Research Institute, University of Groningen, The Netherlands.
J Mol Biol. 1993 Jun 20;231(4):1137-8. doi: 10.1006/jmbi.1993.1360.
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.
墨西哥水蛭药用水蛭（Haementeria officinalis）的唾液腺含有一种15 kDa的蛋白质，它是一种强效且选择性的Xa因子抑制剂。它不仅抑制血液凝固，还抑制转移。一个编码与已发表的抗凝血酶原酶序列相似序列的基因已被合成并在中国仓鼠卵巢（CHO）细胞中表达。重组蛋白在pH 6.0条件下，以31%硫酸铵作为沉淀剂进行纯化和结晶。这些晶体至少能衍射到2.8 Å。空间群为I422，a = b = 77.7 Å，c = 88.4 Å。晶体含有42%的溶剂，不对称单位中有一个蛋白质分子。目前正在寻找重原子衍生物。
