Sagami H, Igarashi Y, Tateyama S, Ogura K, Roos J, Lennarz W J
Institute for Chemical Reaction Science, Tohoku University, Katahira, Sendai, Japan.
J Biol Chem. 1996 Apr 19;271(16):9560-6. doi: 10.1074/jbc.271.16.9560.
Two new polyprenyl products in addition to dehydrodolichol and dolichol were detected by two-plate silica gel thin layer chromatography of nonpolar products formed from [1-14C]isopentenyl diphosphate and farnesyl diphosphate in the reaction with a crude 1,000 x g supernatant of yeast homogenates in the presence of NADPH. The new products were indistinguishable from authentic dehydrodolichal and dolichal. Analyses of the time-dependent and pH-dependent formation of the four products including dehydrodolichal and dolichal suggested that the biosynthetic pathway from dehydrodolichol leading to dolichal is different from that to dolichol. In double-labeled experiments with a combination of -l-14C-isopentenyl diphosphate and a [4B-3H]NADPH-generating system, the ratio of 3H- and 14C-derived radioactivities found in dolichal was six times higher than that in dolichol. A small amount of 3H-labeled dehydrodolichol was also detected. Considering the fact that dolichol is synthesized from dehydrodolichol (Sagami, H., Kurisaki, A., and Ogura, K. (1993) J. Biol. Chem. 268, 10109-10113), we propose that dehydrodolichol is a common branch point intermediate in the biosynthetic pathways leading to dolichal and dolichol and that dehydrodolichal is an intermediate in the pathway from dehydrodolichol to dolichal.
在用[1-¹⁴C]异戊烯基二磷酸和法呢基二磷酸与酵母匀浆1000×g粗上清液在NADPH存在下反应形成的非极性产物的双板硅胶薄层色谱中，除脱氢多萜醇和多萜醇外，还检测到两种新的聚异戊烯基产物。这些新产物与 authentic 脱氢多萜醛和多萜醛无法区分。对包括脱氢多萜醛和多萜醛在内的四种产物的时间依赖性和pH依赖性形成的分析表明，从脱氢多萜醇到多萜醛的生物合成途径与到多萜醇的途径不同。在用 -l-¹⁴C-异戊烯基二磷酸和[4B-³H]NADPH生成系统组合进行的双标记实验中，在多萜醛中发现的³H和¹⁴C衍生放射性的比率比在多萜醇中高六倍。还检测到少量³H标记的脱氢多萜醇。考虑到多萜醇是由脱氢多萜醇合成的（相美，H.，栗崎，A.，和小仓，K.（1993年）《生物化学杂志》268，10109 - 10113），我们提出脱氢多萜醇是通向多萜醛和多萜醇的生物合成途径中的一个共同分支点中间体，并且脱氢多萜醛是从脱氢多萜醇到多萜醛途径中的一个中间体。 （注：“authentic”这里直接保留英文，因为不太明确其在该语境下准确对应的中文专业术语）
