DEPRESSION OF FREEZING-POINT BY GLYCOPROTEINS FROM AN ANTARCTIC FISH
DEPRESSION OF FREEZING-POINT BY GLYCOPROTEINS FROM AN ANTARCTIC FISH
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DOI：
10.1038/243357a0
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发表时间：
1973-01-01
期刊：
影响因子：
64.8
通讯作者：
HOFMANN, R
中科院分区：
文献类型：
--
作者：
FEENEY, RE;HOFMANN, R
Scholander及其同事观察到，某些极地鱼类的血清中含有一种高分子量的物质，这种物质可以降低冰点。最近在南极鱼类中描述了具有这种特征的几种糖蛋白家族的一般性质和结构4 -14。这些“抗冻”糖蛋白（AFGP）由三糖肽Ala-Ala-Thr-o-二糖的重复单元组成。三种活性糖蛋白已被鉴定;它们仅在聚合物长度上不同，分子量范围为10，500至21，000 g mol− 1，通过超离心、光散射或渗透压测定6，11。然而，根据凝固点降低，表观分子量仅为20 g mol−1，该值相当于从分子量计算的降低值的>500倍。
SCHOLANDER and colleagues1–3observed that the blood sera of some polar fishes contain a substance of high molecular weight which lowers the freezing point. The general properties and structures of a family of several glycoproteins with this characteristic have recently been described in Antarctic fishes4–14. These “antifreeze” glycoproteins (AFGP) consist of repeating units of the triglycopeptide Ala-Ala-Thr-o-disaccharide. Three active glycoproteins have been characterized; these differ only in polymer length, with molecular weights ranging from 10,500 to 21,000 g mol−1as determined by ultracentrifugation, light scattering, or osmotic pressure6,11. According to the freezing point depression, however, the apparent molecular weight is only 20 g mol−1, a value equivalent to >500 times the depression calculated from the molecular weights.