Structural Analysis of Intact Biomolecules by Solid State High Resolution Nuclear Magnetic Resonance with Homogenously Isotope Labeled Samples

利用固体高分辨率核磁共振（NMR）技术，建立了完整生物分子结构分析系统。将该系统应用于紫色光合细菌的膜天线LH1和绿色光合细菌的叶绿体天线。用富含同位素化合物的培养基培养细菌，得到同位素标记均匀的样品。用高分辨率核磁共振（NMR）对膜天线LH1进行了初步研究，并将其溶解在脱脂洗涤剂辛烷基-β- d -葡萄糖苷中。由于同位素富集的影响，许多核磁共振信号被分解并分配给细菌叶绿素a。用我们发现的溶剂汽化方法，用同位素标记的细菌叶绿素c制备了模型叶绿体。将该系统应用于模型叶绿体显示出高度分辨的信号，每个信号都是成对出现的。这表明叶绿体是由基本的模糊结构组成的，或者作为两种截然不同的构象存在。

We have established the system for the structural analysis of intact biomolecules by solid state high resolution nuclear magnetic resonance (NMR) with homogenously isotope labeled samples. The system was applied to the membrane antenna LH1 of purple photosynthetic bacteria, and to the chlorosome antenna of green photosynthetic bacteria. The homogenously isotope labeled samples were obtained by cultivation of the bacteria with medium prepared with isotope enriched compounds. The membrane antennae LH1 was preliminary investigated by high resolution NMR in the solution dissolved in deutrated detergent, octyl-β-D-glucopyranoside. Many NMR signals were resolved and assigned for bacteriochlorophyll a due to the effects of the isotope enrichment. The model chlorosomes have been prepared with the isotope labeled bacteriochlorophyll c by the solvent vaporization method found by us. Application of the systems to the model chlorosomes revealed highly resolved signal, each of which appeared in pairwise. This implied that the chlorosomes are composed basic dimmer building block, or exist as two distinctly different conformations.