Fiordemondo Deborah, Stano Pasquale
Biology Department, University of RomaTre, Via le G. Marconi 446, 00146 Rome, Italy.
Chembiochem. 2007 Nov 5;8(16):1965-73. doi: 10.1002/cbic.200700112.
Like liposomes, water-in-oil (w/o) emulsions have recently been used as bioreactors, since they permit facile compartmentation, and therefore the creation of a synthetic cell-like structure. We show here for the first time that lecithin-based w/o compartments can also be used for these purposes and in particular as compartments for hosting complex biochemical reactions that lead to protein synthesis. The expression of enhanced green fluorescent protein (EGFP), used as a model reaction, was followed by fluorescence microscopy. EGFP was synthesised inside the bioreactors either through simultaneous incorporation of all components for transcription and translation reactions in a single emulsion, or through the mixing of four different emulsions, each containing only part of the molecular machinery. Mechanical energy (i.e., stirring) must be provided to the system in order to force solute exchange and/or fusion processes between droplets. Finally, we demonstrate that, in the presence of excess lecithin, preformed w/o compartments can undergo spontaneous division, reducing the average droplet size, increasing the number of droplets, and continuing the protein expression after the division. We briefly comment on how this type of work extends and links the previously reported work on self-reproduction in vesicles, micelles and reverse-micelles.
与脂质体一样，油包水（w/o）乳液最近也被用作生物反应器，因为它们便于进行分隔，从而能够创建类似合成细胞的结构。我们在此首次表明，基于卵磷脂的w/o分隔也可用于这些目的，特别是作为容纳导致蛋白质合成的复杂生化反应的分隔。以增强型绿色荧光蛋白（EGFP）的表达作为模型反应，通过荧光显微镜进行跟踪。EGFP在生物反应器内合成，要么是通过在单一乳液中同时加入转录和翻译反应的所有成分，要么是通过混合四种不同的乳液，每种乳液仅包含部分分子机制。必须向系统提供机械能（即搅拌），以促使液滴之间的溶质交换和/或融合过程。最后，我们证明，在存在过量卵磷脂的情况下，预先形成的w/o分隔能够自发分裂，减小平均液滴尺寸，增加液滴数量，并在分裂后继续进行蛋白质表达。我们简要评论了这类工作如何扩展并联系了先前报道的关于囊泡、胶束和反胶束中自我复制的工作。
