Kotel'nikova R A, Tat'ianenko L V, Moshkovskiĭ Iu Sh
Biofizika. 1987 May-Jun;32(3):420-3.
By the methods of spectroscopy, fluorimetry and chemical modification of tryptophane residues with N-bromsuccinimide, the sarcoplasmic reticulum of rabbit sceletal muscle was shown to contain 18 +/- 1 tryptophane residues per Ca2+-ATPase molecule, 6 of which were, probably, inside the protein globule, in its hydrophobic region, and thus unavailable for modifier, while the rest 12 +/- 1 were easily transformed to the 6-oxyindole chromophore being the main source of the intrinsic fluorescence of the enzyme. The quantum yield for the rest four residues was equal to 0.015. Four tryptophane residues are located at the distance of less than 14 A from the ATP-binding site of the enzyme. The quantum yields of fluorescence for 8 of the tryptophane residues of Ca2+-ATPase were similar and equal to 0.03.
通过光谱学、荧光测定法以及用N-溴代琥珀酰亚胺对色氨酸残基进行化学修饰的方法，研究表明兔骨骼肌肌质网中每个Ca2+-ATP酶分子含有18±1个色氨酸残基，其中6个可能位于蛋白质球体内的疏水区域，因此无法被修饰剂作用，而其余12±1个则很容易转化为6-氧吲哚发色团，这是该酶固有荧光的主要来源。其余四个残基的量子产率为0.015。四个色氨酸残基位于距该酶ATP结合位点小于14埃的距离处。Ca2+-ATP酶的8个色氨酸残基的荧光量子产率相似，均为0.03。
