Tang W J, Castelfranco P A
Department of Botany, University of California, Davis, California 95616.
Plant Physiol. 1968 Aug;43(8):1232-8. doi: 10.1104/pp.43.8.1232.
The effect of activation ("aging") of potato tuber slices on their phospholipid metabolism was investigated. Aged slices were incubated with (14)C labeled choline, ethanolamine, methionine, serine, and acetate. In all cases, the incorporation of radioactivity into the lipid fraction increased with the length of time the slices were aged. This incorporation was shown to be true synthesis and not exchange between precursors and existing phospholipids.The increased incorporation of labeled choline into lipids was mainly due to an increase in its uptake by the tissue, the presence of actidione during aging prevented this increased uptake. The increase in the incorporation of labeled acetate into lipids resulted from the development of a fatty acid synthetase during aging. In the case of ethanolamine, both its uptake into the tissue and its incorporation into the lipid fraction increased.The phospholipids formed from these precursors were identified by paper and thin-layer chromatography. The major compound formed from choline was lecithin, while phosphatidylethanolamine and a small amount of lecithin were formed from ethanolamine.
研究了马铃薯块茎切片的激活（“老化”）对其磷脂代谢的影响。将老化切片与用（14）C标记的胆碱、乙醇胺、蛋氨酸、丝氨酸和乙酸盐一起孵育。在所有情况下，脂质部分中放射性的掺入量都随着切片老化时间的延长而增加。这种掺入被证明是真正的合成，而不是前体与现有磷脂之间的交换。标记胆碱掺入脂质的增加主要是由于组织对其摄取的增加，老化过程中放线菌酮的存在阻止了这种摄取的增加。标记乙酸盐掺入脂质的增加是由于老化过程中脂肪酸合成酶的产生。就乙醇胺而言，其进入组织的摄取及其掺入脂质部分的量都增加了。通过纸色谱法和薄层层析法鉴定了由这些前体形成的磷脂。由胆碱形成的主要化合物是卵磷脂，而由乙醇胺形成的是磷脂酰乙醇胺和少量卵磷脂。
