TIME RESOLVED TRYPTOPHAN FLUORESCENCE FROM CYTOCHROME B5

分子动力学模拟揭示了暴露的血红素边缘 尚未在细胞色素的任何晶体或 NMR 结构中观察到 b5. 这个裂缝可能具有重要的功能 认识到介导直接电子转移的氧化还原伙伴 对于某些复合体。 为了研究裂隙呼吸的动力学 我们启动了单个 Trp-22 的稳态荧光研究。 丙烯酰胺猝灭单一色氨酸大鼠细胞色素 b5 和 通过超快时间分辨技术检查了其各种二硫突变体 光谱学。 为了探究假定的裂缝的动力学， 额外的色氨酸已放置在表面（S18W）。 野生型寿命分布和各向异性衰减的比较 Trp-18 突变体可能提供有关迁移性的新信息 蛋白质裂口区域的蛋白质表面。

Molecular dynamic simulations reveal an exposed heme edge that has not been observed in any crystal or NMR structure of cytochrome b5. This cleft is likely to be of functional importance for recognition of a redox partner for mediating direct electron transfer for some complexes. In order to study dynamics of the cleft breathing we initiated a steady-state fluorescence study of single Trp-22. Acrylamide quenching of the single tryptophan rat cytochrome b5 and its various disufide mutants was examined by ultrafast time-resolved spectroscopy. In order to probe dynamics of the putative cleft, an additional tryptophan has been placed on the surface (S18W). Comparison of lifetime distribution and anisotropy decays of wild-type and mutant with Trp-18 may provide new information about mobility of the protein surface in the cleft region of the protein.