...
首页> 外文期刊>Proceedings of the National Academy of Sciences of the United States of America >Identification of a single peridinin sensing Chl-a excitation in reconstituted PCP by crystallography and spectroscopy
【24h】

Identification of a single peridinin sensing Chl-a excitation in reconstituted PCP by crystallography and spectroscopy

机译:通过晶体学和光谱学鉴定重构的PCP中单个peridinin感测Chl-a激发

获取原文
获取原文并翻译 | 示例
           

摘要

The peridinin-chlorophyll a-protein (PCP) of dinoflagellates is unique among the large variety of natural photosynthetic light-harvesting systems. In contrast to other chlorophyll protein complexes, the soluble PCP is located in the thylakoid lumen, and the carotenoid pigments outnumber the chlorophylls. The structure of the PCP complex consists of two symmetric domains, each with a central chlorophyll a (Chl-a) surrounded by four peridinin molecules. The protein provides distinctive surroundings for the pigment molecules, and in PCP, the specific environment around each peridinin results in overlapping spectral line shapes, suggestive of different functions within the protein. One particular Per, Per-614, is hypothesized to show the strongest electronic interaction with the central Chl-a. We have performed an in vitro reconstitution of pigments into recombinant PCP apo-protein (RFPCP) and into a mutated protein with an altered environment near Per-614. Steady-state and transient optical spectroscopic experiments comparing the RFPCP complex with the reconstituted mutant protein identify specific amino acid-induced spectral shifts. The spectroscopic assignments are reinforced by a determination of the structures of both RFPCP and the mutant by x-ray crystallography to a resolution better than 1.5 A. RFPCP and mutated RFPCP are unique in representing crystal structures of in vitro reconstituted light-harvesting pigment-protein complexes.
机译:鞭毛藻的peridinin-叶绿素a蛋白(PCP)在多种自然光合光捕获系统中是独特的。与其他叶绿素蛋白复合物相反,可溶性PCP位于类囊体腔中,类胡萝卜素色素超过叶绿素。 PCP复合物的结构由两个对称结构域组成,每个结构域均具有一个中央叶绿素a(Chl-a),被四个peridinin分子包围。该蛋白为色素分子提供了独特的环境,在PCP中,每个蛋白抗生物素蛋白周围的特定环境导致重叠的谱线形状,提示该蛋白具有不同的功能。假设一种特殊的Per-Per-614表现出与中央Chl-a的最强电子相互作用。我们在Per-614附近进行了色素体外重组到重组PCP载脂蛋白(RFPCP)和突变蛋白的改造。将RFPCP复合物与重组突变蛋白进行比较的稳态和瞬态光谱实验确定了特定的氨基酸诱导的光谱偏移。通过X射线晶体学确定RFPCP和突变体的结构,使其分辨率优于1.5 A,从而增强了光谱学的归属。RFPCP和突变的RFPCP在代表体外重建的光采色素蛋白的晶体结构方面是独特的复合体。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号