Crystal Structure of Phototoxic Orange Fluorescent Proteins with a Tryptophan-Based Chromophore.
Crystal Structure of Phototoxic Orange Fluorescent Proteins with a Tryptophan-Based Chromophore.
复制标题
具有基于色氨酸的发色团的光毒性橙色荧光蛋白的晶体结构。
DOI：
10.1371/journal.pone.0145740
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发表时间：
2015
期刊：
影响因子：
3.7
通讯作者：
Pletnev S
中科院分区：
文献类型：
--
作者：
Pletneva NV;Pletnev VZ;Sarkisyan KS;Gorbachev DA;Egorov ES;Mishin AS;Lukyanov KA;Dauter Z;Pletnev S
光毒性荧光蛋白代表了一组稀疏的遗传编码的光敏剂，可用于精确的光诱导的靶蛋白失活，DNA损伤和细胞杀伤。迄今为止，只有两种这样的基于GFP的荧光蛋白（FP），KillerRed及其单体变体SuperNova被描述。在这里，我们提出了一个晶体学的研究，他们的两个橙子的继任者，二聚杀人橙子和单体杀人橙子，在1.81和1.57分辨率，分别。它们是第一种具有基于色氨酸的发色团（Gln 65-Trp 66-Gly 67）的橙色发光蛋白光敏剂。与它们的红色祖细胞相同，这两种橙子光敏剂都具有将发色团连接到β-桶外部的充满水的通道，并且能够运输ROS。在这两种蛋白质中，Trp 66的发色团采用了不寻常的反式-顺式构象稳定的H-键与附近的Gln 159。这种反式-顺式构象沿着水通道被证明是一个关键的结构特征，提供明亮的橙子发射和光毒性的两个检查橙子光敏剂。
Phototoxic fluorescent proteins represent a sparse group of genetically encoded photosensitizers that could be used for precise light-induced inactivation of target proteins, DNA damage, and cell killing. Only two such GFP-based fluorescent proteins (FPs), KillerRed and its monomeric variant SuperNova, were described up to date. Here, we present a crystallographic study of their two orange successors, dimeric KillerOrange and monomeric mKillerOrange, at 1.81 and 1.57 Å resolution, respectively. They are the first orange-emitting protein photosensitizers with a tryptophan-based chromophore (Gln65-Trp66-Gly67). Same as their red progenitors, both orange photosensitizers have a water-filled channel connecting the chromophore to the β-barrel exterior and enabling transport of ROS. In both proteins, Trp66 of the chromophore adopts an unusual trans-cis conformation stabilized by H-bond with the nearby Gln159. This trans-cis conformation along with the water channel was shown to be a key structural feature providing bright orange emission and phototoxicity of both examined orange photosensitizers.