【摘要】 PAiRFP1是一种以细菌光敏色素为模板，改造得到的光激活荧光蛋白。与其他光激活荧光蛋白相比，它最大的优势是激发、发射都在近红外区域。本论文围绕该蛋白中含有的8个半胱氨酸残基，开展了定点突变、光谱学检测等工作，发现(1)在8个单突变体中，仅有Cys-29突变改善了光激活蛋白的分子亮度，其它突变都削弱了近红外荧光；(2)伴随着环境氧化、还原条件的改变，C29S突变近红外荧光显著降低，这说明该位点的半胱氨酸残基对于维持该近红外荧光蛋白在氧化还原环境中的稳定性具有重要作用，相关机理尚待深入研究。更多还原

【Abstract】 PAiRFP1 is a photoactivatable fluorescent protein engineered from bacterial phytochrome. Compared with other photoactivatable fluorescent proteins, its biggest advantage is that both excitation and emission are in the near-infrared region. In this paper, we combined site-directed mutagenesis and spectroscopic methods to investigate the 8 cysteine residues contained in the protein, and found that(1) among the 8 single mutants, only Cys-29 mutation improved molecular brightness of photoactivatable protein, but other mutations weakened the near-infrared fluorescence;(2) with the change of environmental oxidation and reduction conditions, the near-infrared fluorescence of the C29S mutation was significantly reduced, which indicates that the cysteine residue at this site plays an important role in maintaining the stability of the near-infrared fluorescent protein in the redox environment, and the related mechanism needs to be further studied.更多还原