Eftink M R, Hagaman K A
Biophys Chem. 1985 Aug;22(3):173-80. doi: 10.1016/0301-4622(85)80040-5.
Cod parvalbumin (isotype III) is a single tryptophan-containing protein. The fluorescence characteristics of this tryptophan residue (lambda em approximately 315 nm) suggest that it is buried from solvent and that it is located in an apolar core of the protein. Solute quenching studies of the tryptophan fluorescence of parvalbumin reveal dynamic quenching rate constants, kq, of 1.1 X 10(8) and 2.3 X 10(9) M-1 s-1 (at 25 degrees C) with acrylamide and oxygen, respectively, as quenchers. From temperature dependence studies, activation energies of 6.5 +/- 1.5 and 6.0 +/- 0.5 kcal/mol are found for acrylamide and oxygen quenching. The kq for acrylamide quenching is found to be relatively unchanged (+/- 10%) by an 8-fold increase in the bulk viscosity (glycerol/water mixture). These temperature and viscosity studies argue that the acrylamide quenching process involves a dynamic penetration of the quencher, facilitated by fluctuations in the protein's structure.
鳕鱼小清蛋白（同型III）是一种含单个色氨酸的蛋白质。该色氨酸残基的荧光特性（发射波长约为315nm）表明它被掩埋于溶剂之外，且位于蛋白质的非极性核心区域。对小清蛋白色氨酸荧光的溶质猝灭研究显示，以丙烯酰胺和氧气作为猝灭剂时，动态猝灭速率常数kq在25℃下分别为1.1×10⁸和2.3×10⁹M⁻¹s⁻¹。通过温度依赖性研究发现，丙烯酰胺和氧气猝灭的活化能分别为6.5±1.5和6.0±0.5kcal/mol。发现当本体粘度增加8倍（甘油/水混合物）时，丙烯酰胺猝灭的kq相对不变（±10%）。这些温度和粘度研究表明，丙烯酰胺猝灭过程涉及猝灭剂的动态渗透，这是由蛋白质结构的波动所促进的。
