Gabrielides C, Kapoulas V M
J Protozool. 1981 Nov;28(4):441-7. doi: 10.1111/j.1550-7408.1981.tb05317.x.
[14C] chimyl and [3H] batyl alcohols were added to Crithidia fasciculata cultures during the mid-log phase of cell growth, and the lipid extracts of the cells were analyzed for degradation products. C. fasciculata cells were able to take up exogenous glyceryl ethers, and in amounts as high as the endogenous lipid content. The glyceryl ether taken up by the cells was incorporated into lipids either prior to the ether bond cleavage or after degradation to fatty acid. The extent of degradation and the degree of incorporation of degradation products into cellular lipid were higher for chimyl than for batyl alcohol. Batyl alcohol was not metabolized efficiently, leading to the formation of large intracellular pools of free substrate. One product of glyceryl ether degradation was identified as alkyl-dihydroxy acetone, and was detected inside and outside of the cells. The data strongly suggest that this product is the first stable intermediate in the degradation process and indicate that the extracellular formation of alkyl-dihydroxy acetone is due to the action of exoenzymes secreted by the cells. The constant detection of alk-l-enyl glycerol among the degradation products indicates the existence of a second mechanism in C. fasciculata for converting the alkyl-to alkenyl-glycerol.
在细胞生长的对数中期，将[¹⁴C]鲨肝醇和[³H]巴豆醇添加到纤细锥虫培养物中，并分析细胞的脂质提取物中的降解产物。纤细锥虫细胞能够摄取外源性甘油醚，摄取量高达内源性脂质含量。细胞摄取的甘油醚在醚键断裂之前或降解为脂肪酸之后被整合到脂质中。鲨肝醇的降解程度和降解产物整合到细胞脂质中的程度高于巴豆醇。巴豆醇代谢效率不高，导致细胞内形成大量游离底物池。甘油醚降解的一种产物被鉴定为烷基二羟基丙酮，在细胞内外均有检测到。数据强烈表明该产物是降解过程中的第一个稳定中间体，并表明细胞外烷基二羟基丙酮的形成是由于细胞分泌的外酶的作用。在降解产物中持续检测到alk-1-烯基甘油表明纤细锥虫中存在将烷基甘油转化为烯基甘油的第二种机制。
