Scripps Institution of Oceanography, University of California, San Diego, La Jolla, California 92093.
Plant Physiol. 1978 Jul;62(1):36-9. doi: 10.1104/pp.62.1.36.
Carotenoid-rich oil globules were isolated from the cytoplasm of the binucleate dinoflagellate, Peridinium foliaceum. These orange globules were collected from ruptured cells by ultracentrifugation on a sucrose density gradient, and checked for purity by electron microscopy. The osmiophilic globules were assayed for lipid (including pigment) and protein content. The lipid to protein ratio was 1.39:1, with a calculated density of the globules of 1.05 grams per cubic centimeter. The lipids were composed of hydrocarbon, wax ester (phytyl ester), triglyceride, and polar (no phospholipid) fractions. The biochemical composition indicated that the globules function as a reservoir of energy-rich components in the cell. Microspectrophotometric observations were consistent with pigment analyses which demonstrated that the globules were carotenoid-rich. In addition to beta-carotene, gamma-carotene, and canthaxanthin, the carotenogenic precursors: phytoene, phytofluence, zeta-carotene and beta-zeacarotene were isolated from the globules. Corrected fluorescence maxima of phytoene and phytofluene in hexane were recorded at 340 and 490 nanometers, respectively. Carotenes constituted 3.3% of the total oil globule lipid. The possibility of an extraplastidic carotenogenic enzyme system in P. foliaceum is discussed.
富含类胡萝卜素的油球从双核甲藻，双鞭甲藻的细胞质中分离出来。这些橙色的油球通过蔗糖密度梯度超速离心从破裂的细胞中收集，并通过电子显微镜检查其纯度。亲脂性油球的脂质（包括色素）和蛋白质含量进行了检测。脂质与蛋白质的比例为 1.39:1，计算得出油球的密度为每立方厘米 1.05 克。脂质由烃、蜡酯（植基酯）、甘油三酯和极性（无磷脂）馏分组成。生化组成表明，这些油球作为细胞中富含能量成分的储存库发挥作用。微量分光光度观察与色素分析结果一致，表明油球富含类胡萝卜素。除了β-胡萝卜素、γ-胡萝卜素和角黄素外，还从油球中分离出类胡萝卜素前体：phytoene、phytofluence、ζ-胡萝卜素和β-玉米黄质。在己烷中phytoene 和 phytofluene 的校正荧光最大值分别记录为 340 和 490 纳米。类胡萝卜素占总油球脂质的 3.3%。讨论了在 P. foliaceum 中存在质体外的类胡萝卜素生物合成酶系统的可能性。
