Sun J, Yamaguchi M, Yuda M, Miura K, Takeya H, Hirai M, Matsuoka H, Ando K, Watanabe T, Suzuki K, Chinzei Y
Department of Medical Zoology, Mie University School of Medicine, Tsu, Japan.
Thromb Haemost. 1996 Apr;75(4):573-7.
The salivary glands of the blood sucking insect, Rhodnius prolixus, have an anticoagulant, prolixin-S, which was reported as a specific inhibitor of intrinsic coagulant pathway. Prolixin-S was purified from the salivary glands extract of Rhodnius prolixus by gel filtration and anion exchange HPLC by assaying prolongation of activated partial thromboplastin time (APTT). The isolated protein specifically inhibited factor IXa-catalyzed activation of factor X in the presence of Ca2+ and phospholipids irrespective of the presence or absence of factor VIIIa. The anticoagulant factor had red color and a specific absorbance peak at 402 nm and thus it was identified as a heme protein. A Rhodnius prolixus salivary gland cDNA library was prepared, screened with an antibody against prolixin-S and its complete cDNA sequence was determined. cDNA and deduced amino acid sequences showed that prolixin-S is a novel anticoagulant of 19,922 Da, which has no sequence homology with any other anticoagulant reported so far.
吸血昆虫罗阿丝虫的唾液腺含有一种抗凝血剂——罗阿丝虫素 - S，据报道它是内源性凝血途径的特异性抑制剂。通过测定活化部分凝血活酶时间（APTT）的延长，利用凝胶过滤和阴离子交换高效液相色谱法从罗阿丝虫的唾液腺提取物中纯化出罗阿丝虫素 - S。分离出的蛋白质在有或没有因子 VIIIa 存在的情况下，在 Ca2+ 和磷脂存在时能特异性抑制因子 IXa 催化的因子 X 的活化。该抗凝血因子呈红色，在 402 nm 处有一个特异性吸收峰，因此被鉴定为一种血红素蛋白。制备了罗阿丝虫唾液腺 cDNA 文库，用抗罗阿丝虫素 - S 的抗体进行筛选，并确定了其完整的 cDNA 序列。cDNA 和推导的氨基酸序列表明，罗阿丝虫素 - S 是一种分子量为 19,922 Da 的新型抗凝血剂，与迄今为止报道的任何其他抗凝血剂都没有序列同源性。
