Précigoux G, Geoffre S, Léonard R, Llido S, Dautant A, d'Estaintot B L, Picard P, Ménard A, Guillemain B, Hospital M
Laboratoire de Cristallographie, URA 144 CNRS, Université de Bordeaux I, Talence, France.
FEBS Lett. 1993 Jul 12;326(1-3):237-40. doi: 10.1016/0014-5793(93)81798-5.
Bovine leukaemia virus (BLV) is the aetiological agent of Leukosis enzootica bovis [Viral Oncology (1980), G. Klein (Ed.) Raven Press, New York, pp. 231-238], a widely spread disease in cattle. BLV is reported as the animal model of human T-cell leukaemia virus (HLTV) which is the causative agent of adult T-cell leukaemia and tropical spastic paraparesis. Like the viruses themselves, the two retroviral proteinases (PR) are very closely related [Virology 142 (1985) 357-377]. BLV and HTLV-I PR are reported as putative proteins made of 126 [J. Virol. 57 (1986) 826-832] and 125 [FEBS Lett. 293 (1991) 106-110] amino acids, respectively (long sequences), belonging to the aspartyl proteinase family [Nature 329 (1987) 351-354], with the aid of molecular modelling, we show that BLV and HTLV-I proteinases made of only 116 and 115 amino acids, respectively (short sequences), display three-dimensional structures similar to that observed for other retroviral aspartyl proteinases. The models are based on three-dimensional structures of Rous sarcoma virus (RSV PR) and the human immunodeficiency virus (HIV-1 PR). We used solid phase peptide synthesis to produce the putative proteolytic enzyme of BLV (116 amino acids). In this study, we show that the folded synthetic protease accurately hydrolyzes a decapeptide corresponding to the sequence of the Matrice-Capside (MA/CA) cleavage site of the gag polyprotein. In addition, the proteolytic activity is inhibited by a statine ((4S,3S)-4-amino-3-hydroxyl-6-methylheptanoic acid) containing an analogous sequence.
牛白血病病毒（BLV）是牛地方流行性白血病的病原体[《病毒肿瘤学》（1980年），G. 克莱因（编），拉文出版社，纽约，第231 - 238页]，这是一种在牛群中广泛传播的疾病。据报道，BLV是人类T细胞白血病病毒（HTLV）的动物模型，而HTLV是成人T细胞白血病和热带痉挛性截瘫的病原体。与病毒本身一样，这两种逆转录病毒蛋白酶（PR）密切相关[《病毒学》142（1985年）357 - 377]。据报道，BLV和HTLV - I PR分别是由126个[《病毒学杂志》57（1986年）826 - 832]和125个[《欧洲生物化学学会联合会快报》293（1991年）106 - 110]氨基酸组成的推定蛋白质（长序列），属于天冬氨酸蛋白酶家族[《自然》329（1987年）351 - 354]。借助分子建模，我们表明分别由116个和115个氨基酸组成的BLV和HTLV - I蛋白酶（短序列）呈现出与其他逆转录病毒天冬氨酸蛋白酶相似的三维结构。这些模型基于劳氏肉瘤病毒（RSV PR）和人类免疫缺陷病毒（HIV - 1 PR）的三维结构。我们使用固相肽合成法制备了BLV的推定蛋白水解酶（116个氨基酸）。在本研究中，我们表明折叠后的合成蛋白酶能准确水解与gag多蛋白的基质 - 衣壳（MA/CA）切割位点序列相对应的十肽。此外，含有类似序列的statine（（4S，3S）-4 - 氨基 - 3 - 羟基 - 6 - 甲基庚酸）可抑制其蛋白水解活性。
