Institute of Biochemistry, Odense University, Campusvej 55, DK-5230, Odense M, Denmark.
Photosynth Res. 1993 Mar;35(3):275-83. doi: 10.1007/BF00016558.
Isolated chlorosomes, treated with the detergent lithium dodecyl sulfate (LDS), can be separated into two green fractions by agarose gel electrophoresis. One fraction contains chlorosomes with a full complement of proteins and antenna BChl c absorbing at 740 nm, but with a more spherical form than the normal ellipsoid shape observed in control chlorosomes. The second fraction was completely devoid of proteins but had a similar absorption spectrum. Electron micrographs of the protein-free fraction indicated the presence of stain-excluding spheres with overall dimensions resembling those of intact chlorosomes (40-100 nm). These spheres are probably micelles of BChl c liberated from the chlorosomes during the detergent treatment, since similar structures could be produced when purified BChl c, dissolved in 1-hexanol, was dispersed in buffer, producing an aggregate absorbing at 742 nm. These results suggest that the chlorosome proteins are not required to produce an arrangement of BChl c chromophores which gives rise to a 740 nm absorption peak resembling that of intact chlorosomes. It seems probable, however, that proteins have a role in determining the overall shape of the chlorosome. Treatment with cross-linking reagents did not prevent the detergent-induced changes in chlorosome morphology.
用去污剂十二烷基硫酸钠（LDS）处理的分离叶绿素体，可通过琼脂糖凝胶电泳分离成两个绿色部分。一个部分包含完整的蛋白质和天线 BChl c 在 740nm 处吸收的叶绿素体，但形态比对照叶绿素体中观察到的正常椭圆形更具球形。第二个部分完全没有蛋白质，但具有相似的吸收光谱。无蛋白部分的电子显微镜照片表明存在染色排除球体，其总体尺寸与完整叶绿素体相似（40-100nm）。这些球体可能是在去污剂处理过程中从叶绿素体中释放出的 BChl c 的胶束，因为当在缓冲液中分散溶解在 1-己醇中的纯化 BChl c 时，可以产生吸收峰在 742nm 处的类似结构。这些结果表明，叶绿素体蛋白不是产生导致 740nm 吸收峰类似于完整叶绿素体的 BChl c 发色团排列所必需的。然而，蛋白质在确定叶绿素体的整体形状方面可能具有作用。用交联试剂处理并不能防止去污剂诱导的叶绿素体形态变化。
