Nakatani Yoichi, Ribeiro Nigel, Streiff Stéphane, Gotoh Mari, Pozzi Gianluca, Désaubry Laurent, Milon Alain
Institute of Chemistry, University of Strasbourg - CNRS, 67000, Strasbourg, France,
Orig Life Evol Biosph. 2014 Sep;44(3):197-208. doi: 10.1007/s11084-014-9365-6. Epub 2014 Oct 30.
Terpenoids have an essential function in present-day cellular membranes, either as membrane reinforcers in Eucarya and Bacteria or as principal membrane constituents in Archaea. We have shown that some terpenoids, such as cholesterol and α, ω-dipolar carotenoids reinforce lipid membranes by measuring the water permeability of unilamellar vesicles. It was possible to arrange the known membrane terpenoids in a 'phylogenetic' sequence, and a retrograde analysis led us to conceive that single-chain polyprenyl phosphates might have been 'primitive' membrane constituents. By using an optical microscopy, we have observed that polyprenyl phosphates containing 15 to 30 C-atoms form giant vesicles in water in a wide pH range. The addition of 10 % molar of some polyprenols to polyprenyl phosphate vesicles have been shown to reduce the water permeability of membranes even more efficiently than the equimolecular addition of cholesterol. A 'prebiotic' synthesis of C10 and C15 prenols from C5 monoprenols was achieved in the presence of a montmorillonite clay. Hypothetical pathway from C1 or C2 units to 'primitive' membranes and that from 'primitive' membranes to archaeal lipids are presented.
萜类化合物在当今细胞膜中具有重要功能，在真核生物和细菌中作为膜强化剂，在古细菌中作为主要膜成分。我们通过测量单层囊泡的水渗透性表明，一些萜类化合物，如胆固醇和α,ω-偶极类胡萝卜素可强化脂质膜。可以将已知的膜萜类化合物按“系统发育”顺序排列，逆向分析使我们设想单链聚异戊二烯磷酸酯可能是“原始”膜成分。通过光学显微镜，我们观察到含15至30个碳原子的聚异戊二烯磷酸酯在较宽的pH范围内于水中形成巨型囊泡。已表明向聚异戊二烯磷酸酯囊泡中添加10%摩尔的某些聚异戊烯醇比等分子添加胆固醇更有效地降低膜的水渗透性。在蒙脱石粘土存在下实现了由C5单异戊烯醇“益生元”合成C10和C15聚异戊烯醇。展示了从C1或C2单元到“原始”膜以及从“原始”膜到古细菌脂质的假设途径。
