通过稳态和时间分辨荧光光谱揭示的小白蛋白构象异构体

Parvalbumin conformers revealed by steady-state and time-resolved fluorescence spectroscopy.

作者信息

Permyakov E A, Ostrovsky A V, Burstein E A, Pleshanov P G, Gerday C

出版信息

Arch Biochem Biophys. 1985 Aug 1;240(2):781-91. doi: 10.1016/0003-9861(85)90087-6.

Abstract

The binding of calcium to whiting (one tryptophan residue) and pike (one tyrosine residue) parvalbumins has been studied by means of kinetic and steady-state fluorescence techniques. The decay curves of the tryptophan and tyrosine fluorescence of the parvalbumins are best fitted by a sum of two exponents for any metal state of the proteins. The data can be interpreted as a nonexponential decay of the fluorescence of a single-type chromophore or in terms of equilibria between compact and relaxed conformers of the parvalbumins in each metal state. Fluorescence quenching by I-ions and effects of H2O/D2O substitution confirm the second interpretation. The constants of the equilibria have been evaluated.

摘要

已通过动力学和稳态荧光技术研究了钙与牙鳕（一个色氨酸残基）和狗鱼（一个酪氨酸残基）小清蛋白的结合。对于蛋白质的任何金属状态，小清蛋白的色氨酸和酪氨酸荧光的衰减曲线最适合用两个指数之和来拟合。这些数据可以解释为单一类型发色团荧光的非指数衰减，或者根据每种金属状态下小清蛋白紧密构象和松弛构象之间的平衡来解释。I⁻离子引起的荧光猝灭以及H₂O/D₂O替代的影响证实了第二种解释。已评估了平衡常数。