光谱法研究变性剂对苦荞麦蛋白质构象的影响

摘要

采用紫外差示光谱和荧光光谱研究了不同浓度的乙醇溶液和盐酸胍溶液对苦荞麦蛋白质(TBWSP31)构象变化的影响.研究表明,TBWSP31的色氨酸残基和酪氨酸残基有的位于分子内部,有的暴露于分子表面.乙醇溶液使TBWSP31变性时,仅仅是分子的外层结构发生了变化,分子内部疏水核的变化较小,高浓度的盐酸胍使位于TBWSP31分子内部疏水核的酪氨酸和色氨酸转移到分子表面,暴露于溶剂中,所处的微环境发生了很大的变化.%The effect of ethanol and GuHCl solution on the structure of tartary buckwheat protein(TBWSP31)was studied by UV differential absorption and fluorescence emission spectra. The alcohol denaturation of TBWSP31 was a kind of partial denaturation. The hydrophobic core of TBWSP31 remained intact and the conformation of the hydrophilic shell was changed.When TBWSP31 was denatured by GuHCl solution with higher concentration, Tyr and Trp residues were exposed to the polar aqueous solvents from the hydrophobic core, and the microenvironment showed a great change.