Anderson J M, Barrett J
Ciba Found Symp. 1978(61):81-104. doi: 10.1002/9780470720431.ch5.
Thylakoid membranes from several brown algae have been fragmented with the non-ionic detergent, Triton X-100. Three intrinsic chlorophyll-protein complexes with different pigment compositions have been isolated by sucrose density gradient centrifugation. Brown algae contain the photosystem 1 reaction-centre complex, a P700-chlorophyll a-protein which has similar spectroscopic and chemical properties to those of higher plants. This complex represents about 10--20% of the total chlorophyll in all species; the Acrocarpia paniculata complex has a chlorophyll/P700 ratio of 38. Two main light-harvesting complexes have also been isolated, which have properties unique to brown algae. The heavier of these, an orange fraction, is a fucoxanthin-chlorophyll a/c-protein; this complex contains most of the fucoxanthin and has only chlorophyll c2. The other, a green fraction, is a chlorophyll a/c-protein enriched in violaxanthin. Neither of these complexes possesses detectable photosystem 1 or photosystem 2 activities. Both of these complexes efficiently transfer light energy to chlorophyll a, indicating that the molecular arrangement of their pigments is similar to that in vivo. Differential extraction of thylakoid membranes indicates that the P700-chlorophyll a-protein is the complex most firmly embedded in the membrane, but the fucoxanthin-chlorophyll a/c-protein is the least firmly bound. We suggest that the fucoxanthin complex is the most variable component of the photosynthetic unit of brown algal chloroplasts.
几种褐藻的类囊体膜已用非离子去污剂Triton X-100进行了破碎。通过蔗糖密度梯度离心法分离出了三种具有不同色素组成的内在叶绿素-蛋白质复合物。褐藻含有光系统1反应中心复合物，一种P700-叶绿素a-蛋白质，其光谱和化学性质与高等植物的相似。该复合物在所有物种的总叶绿素中占约10%-20%；顶果藻复合物的叶绿素/P700比值为38。还分离出了两种主要的捕光复合物，它们具有褐藻特有的性质。其中较重的一种橙色组分是岩藻黄质-叶绿素a/c-蛋白质；该复合物含有大部分岩藻黄质，仅含有叶绿素c2。另一种绿色组分是富含紫黄质的叶绿素a/c-蛋白质。这些复合物都不具有可检测到的光系统1或光系统2活性。这两种复合物都能有效地将光能传递给叶绿素a，表明其色素的分子排列与体内相似。类囊体膜的差异提取表明，P700-叶绿素a-蛋白质是最牢固地嵌入膜中的复合物，但岩藻黄质-叶绿素a/c-蛋白质结合最不牢固。我们认为岩藻黄质复合物是褐藻叶绿体光合单位中最可变的组分。
