中文摘要
水晶體蛋白是脊椎動物水晶體中主要的蛋白質，包含A和B兩種單體，水晶體蛋白和小熱休克蛋白質(small heat shock proteins)是屬於同源性蛋白質，且具有分子伴護功能。為了進行結構和功能上的研究，由四週大的大白鼠水晶體中純化出α水晶體蛋白，分別在不同pH值環境中，藉由螢光光譜、圓二色光譜、紫外線光譜的測量來研究α水晶體蛋白的結構和其集結情況與其分子伴護功能。並由檢視水晶體蛋白防止γ水晶體蛋白的熱沉澱時，經實驗結果顯示α水晶體蛋白在不同的酸度環境中，其pH值會影響其伴護效果，且經ANS螢光和類似伴護活性的關連性顯示，結果顯示出表面疏水性之大小對α水晶體蛋白伴護功能無成正比之關係。

Abstract
-Crystallin, the major component of lens proteins, includes A and B two subunits in vertebrate eye lenses . -Crystallin is known to have chaperone-like activity and is shown to have homology with small heat-shock proteins in amino acid sequence. In order to study the structure-functionality relationship, -crystallin were isolated from four weeks old Rat lenses. By fluorescence -spectropolarimetry, circular- dichroism spectropolarimetry, UV absorption spectropolarimetry measure under various values of pH environmental, to study the relationship
between the -crystallin structure and functionality. -Crystallin acts in a chaperone-like manner to prevent the aggregation of γ-crystallin caused by heat-induced denaturation under various pH values. The correlation between the ANS fluorescence and the chaperone-like activity suggests that surface hydrophobicity was not positively related
to the chaperone activity .

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