Liang J N, Chylack L T
Biochem Biophys Res Commun. 1984 Sep 28;123(3):899-906.
Non-enzymatic glycosylation of calf alpha-crystallin was induced by incubation with glucose. Glycosylated and non-glycosylated proteins were separated by affinity chromatography on Glyco Gel B boronic acid and were studied by circular dichroism (CD) and fluorescence. CD indicated that the glycosylated protein secondary structure was not altered, but the tertiary structure did undergo some changes. The CD band of this protein between 290 and 310 nm decreased in intensity. Extrinsic fluorescence probes, TNS (6-(p-toluidinyl) naphthalene-2-sulfonate) and MIANS (6-(4'-maleimidyl-anilino) naphthalene-2-sulfonic acid), indicated changes in both TNS binding sites and the sulfhydryl groups to a less hydrophobic microenvironment. Our results suggest that the glycosylation of protein leads to partial unfolding, and facilitates the sulfhydryl to oxidation.
通过与葡萄糖孵育诱导小牛α-晶状体蛋白的非酶糖基化。糖基化和非糖基化蛋白通过在硼酸糖凝胶B上的亲和色谱法分离，并通过圆二色性（CD）和荧光进行研究。CD表明糖基化蛋白的二级结构未改变，但三级结构确实发生了一些变化。该蛋白在290至310nm之间的CD带强度降低。外在荧光探针TNS（6-（对甲苯胺基）萘-2-磺酸盐）和MIANS（6-（4'-马来酰亚胺基苯胺基）萘-2-磺酸）表明TNS结合位点和巯基都向疏水性较低的微环境发生了变化。我们的结果表明，蛋白质的糖基化导致部分解折叠，并促进巯基氧化。
