A reevaluation of the fluorescence of the core chlorophylls of Photosystem I
A reevaluation of the fluorescence of the core chlorophylls of Photosystem I
复制标题
光系统 I 核心叶绿素荧光的重新评估
DOI：
10.1016/0005-2728(86)90041-1
复制
发表时间：
1986
期刊：
影响因子：
--
通讯作者：
J. Thornber
中科院分区：
文献类型：
--
作者：
R. Nechushtai;Saeid D. Nourizadeh;J. Thornber
表面活性剂诱导的类囊体膜和各种光系统I（PS I）的核心叶绿素蛋白质复合物从高等植物和嗜热蓝藻分离的77 K荧光光谱的变化。Triton X-100，十二烷基硫酸钠，并在较小程度上，十二烷基麦芽糖苷转移的735 nm的荧光PS I在高等植物类囊体到更短的波长，而在蓝藻在相同比例的表面活性剂/叶绿素，只有几个纳米的位移发生。一种高等植物PS I核心复合物，其具有约1000的叶绿素P-700。65，以及P-700-叶绿素a-亚基I复合物（叶绿素P-700约为100）。40)在Triton或十二烷基硫酸钠的存在下，在670-685 nm区域发射最大。然而，当与这些复合物相关的表面活性剂被交换为十二烷基麦芽糖苷时，在它们的发射最大值中发生到721-725 nm的可逆移位，但它们的生化组成没有变化。PS I核心复合物的荧光最大波长可能接近725 nm。由表面活性剂引起的发射光谱的变化表明控制存在的表面活性剂的类型和量以防止复合物获得人为波长最大值的重要性。这些数据解释了为什么不同的最大值已被报道为基本相同的PS I核心叶绿素蛋白制剂，并表明PS I核心复合物荧光的起源不改变叶绿素分子从PS I核心复合物中提取的Triton。
Surfactants induced changes in the 77 K fluorescence spectra of thylakoid membranes and of various Photosystem I (PS I) core chlorophyll-protein complexes isolated from higher plants and a thermophilic cyanobacterium. Triton X-100, sodium dodecyl sulfate and, to a much lesser extent, dodecyl maltoside shift the 735 nm fluorescence of PS I in higher plant thylakoids to much shorter wavelengths, while in the cyanobacterium at the same ratios of surfactant/chlorophyll, a shift of only a few nanometers occurs. A higher plant PS I core complex, having a chlorophyll P-700 of approx. 65, and a P-700-chlorophyll a-subunit I complex (chlorophyll P-700 approx. 40) emit maximally in the 670–685 nm region in the presence of Triton or sodium dodecyl sulfate. However, when the surfactants associated with these complexes were exchanged for dodecyl maltoside, a reversible shift to 721–725 nm occurred in their emission maxima, but there was no change in their biochemical compositions. The unaltered wavelength maximum of the fluorescence of PS I core complex is likely to be close to 725 nm. Shifts of the emission spectrum caused by surfactants indicate the importance of controlling the type and amount of surfactant present to prevent an artifactual wavelength maximum being obtained for a complex. The data explain why different maxima have been reported for essentially identical PS I core chlorophyll-protein preparations, and indicate that the origin of PS I core complex fluorescence does not change as chlorophyll molecules are extracted from PS I core complex by Triton.