Higher structure of pigment in green photosynthetic bacteria

1.在已醇饱和的缓冲液中悬浮时，雪鳞草叶绿体在747 nm处的红外峰移至670 nm处，这与叶绿体中BChl - c的高级结构去组织相对应。当己醇处理的叶绿体用快速缓冲液缓慢稀释时，670 nm波段返回到750 nm，没有明显的中间体。另一方面，当己醇处理的叶绿体与缓冲液快速混合时，670 nm的波段在数小时内通过中间形式恢复到738 nm，在710,720和730 nm附近有明显的峰。这些结果表明，在己醇处理的叶绿体中，bch1c可能有两种不同的重组过程。一种是通过含有少量色素分子的中间形式。另一种是从“单体”形式直接发展成更大的聚合形式。这种直接的过程似乎是形成本地聚合形式所必需的。叶绿体中的细菌叶绿素c有两种主要的光谱形式，它们的吸收峰和CD光谱不同。在己醇处理叶绿体后细菌叶绿素c的重组中，我们之前已经表明重组形式的峰值波长取决于己醇去除的速度。当缓慢去除己醇时，CD光谱显示两种成分的混合物，就像在天然叶绿体中一样。当它被快速去除时，光谱是短波长的。在色素-脂质聚集体中，CD光谱呈短波长型。然而，经己醇处理后，观察到混合CD信号。这些结果表明，这两种形式也可以在色素-脂质聚集体中形成，并且较长波长的形式可能需要较短波长的形式共存。

1.The infrared peak of chlorosomes of C.tepidum at 747 nm shifted to 670 nm when suspended in buffer saturated with hexanol, corresponding to the de-organization of higher structure of BChl c in chlorosomes. When the hexanol-treated chlorosomes were slowly diluted with frash buffer, the 670 nm band returned to 750 nm without apparent intermediates. On the other hand, when the hexanol-treated chlorosomes were rapidly mixed with buffer, the 670 nm band returned to 738 nm in hours through intermediary forms with apparent peaks around 710,720 and 730 nm. These results suggest that two different processes of reorganization of BChl c in hexanol-treated chlorosomes are possible. One is through intermediary forms with smaller numbers of pigment molecules. The other is a direct development of larger aggregated forms from the "monomeric" form. This direct process seems to be necessary to form the native aggregated forms.2.Bacteriochlorophyll c in chlorosomes shows two major spectral forms which are different in absorption peaks and CD spectra. In the reorganization of bacteriochlorophyll c after the hexanol treatment of chlorosomes, we have previously shown that the peak wave-lengths of the reorganized forms were depended on the speed of hexanol removal. When hexanol was removed slowly, CD spectrum showed a mixture of two components as in native chlorosomes. Wken it was removed rapidly, the spectrum is a short-wavelength type. In the pigment-lipid aggregates, CD spectra showed the short-wavelength type. However, after the hexanol treatment the mixed CD signal was observed. These results suggest that the two forms can also formed in the pigment-lipid aggregates, and that the longer wavelength form may require the co-existence of the shorter wavelength form.