人血浆和重组因子七世。表征O-glycosylations丝氨酸残基52和60和定点诱变的丝氨酸52丙氨酸的影响。
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Bjoern年代,培养,使L, Wiberg FC,克里斯滕森M, Komiyama Y,需要好好啊,Kisiel W
人血浆和重组因子七世。表征O-glycosylations丝氨酸残基52和60和定点诱变的丝氨酸52丙氨酸的影响。
生物化学杂志。1991年6月15日;266 (17):11051 - 7。
- PubMed ID
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1904059 (在PubMed]
- 文摘
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第七因子是一个多畴的,维生素K-dependent血浆糖蛋白,参与凝血的外在途径。早期研究证明了一个新颖的二糖(Xyl-Glc)或三糖(Xyl2-Glc) O-glycosidically与丝氨酸52人血浆因子VII(西村,H。川端康成,S。Kisiel, W。哈泽,S。Ikenaka, T。Shimonishi, Y。Iwanaga, s(1989)生物。264年化学,20320 - 20325)。在目前的研究中,人类的等离子体和重组因子VII被孤立,受到酶的碎片。肽组成的残留第一表皮生长因子以48 - 62第七每个因素制备分离领域进行比较分析。使用氨基酸测序策略相结合,碳水化合物和氨基酸组成分析,质谱,三个不同的多糖结构组成的葡萄糖,glucose-xylose,或葡萄糖(木糖)2检测O-glycosidically与丝氨酸52在等离子体和重组因子七世。大约等量的三个多糖结构中观察到等离子体因子七世,而在重组因子VII葡萄糖和葡萄糖(木糖)2结构成为主流。 In addition to the O-linked glycan structures observed at serine 52, a single fucose was found to be covalently linked at serine 60 in both human plasma and recombinant factor VII. Carbohydrate and mass spectrometry analyses indicated that the fucosylation of serine 60 was virtually quantitative. Metabolic labeling studies using [14C]fucose confirmed the presence of O-linked fucose at serine 60. In order to assess whether the carbohydrate moiety at serine 52 contributes to the biological activity of factor VII, we have constructed a site-specific mutant of recombinant factor VII in which serine 52 has been replaced with an alanine residue. Mutant factor VIIa exhibited approximately 60% of the coagulant activity of wild-type factor VIIa in a clotting assay. The amidolytic activity of mutant factor VIIa was indistinguishable from that observed for recombinant wild-type factor VIIa. In addition, the ability of mutant factor VIIa in complex with either purified relipidated tissue factor apoprotein or tissue factor on the surface of a human bladder carcinoma cell line (J82) to activate either factor X or factor IX was virtually identical to that observed for wild-type factor VIIa. These results indicate that the carbohydrate moiety O-glycosidically linked to serine 52 does not appear to be involved either in the interaction of factor VIIa with tissue factor, or the expression of its proteolytic activity toward factor X or factor IX following complex formation with tissue factor.(ABSTRACT TRUNCATED AT 400 WORDS)