Grimaldi S, Robbins J, Edelhoch H
Biochemistry. 1985 Jul 2;24(14):3771-6. doi: 10.1021/bi00335a053.
The fluorescence properties of human thyroxine binding globulin were evaluated during enzymatic deglycosylation by using both neuraminidase and a mixture of glycosidases. Three fluorescent chromophores, one intrinsic and two extrinsic, were monitored, and all showed changes in fluorescent parameters that have been interpreted in terms of a loss of interactions between the carbohydrate and amino acid residues during deglycosylation. The loss of carbohydrates also results in a decrease in stability of the protein to both acid and guanidinium chloride inactivation. Since deglycosylation decreases the frictional ratio of thyroxine binding globulin, it is concluded that, although sialic acid and other sugar residues are in contact with the protein surface, the hydrated carbohydrate chains protrude partially into the solvent.
通过使用神经氨酸酶和糖苷酶混合物对人甲状腺素结合球蛋白进行酶促去糖基化过程中，对其荧光特性进行了评估。监测了三种荧光发色团，一种是内在的，两种是外在的，并且所有荧光发色团都显示出荧光参数的变化，这些变化已根据去糖基化过程中碳水化合物与氨基酸残基之间相互作用的丧失来解释。碳水化合物的丧失还导致蛋白质对酸和氯化胍失活的稳定性降低。由于去糖基化降低了甲状腺素结合球蛋白的摩擦比，因此得出结论，尽管唾液酸和其他糖残基与蛋白质表面接触，但水合碳水化合物链部分伸入溶剂中。
