Wagner N, Gutweiler M, Pabst R, Dose K
Eur J Biochem. 1987 May 15;165(1):177-83. doi: 10.1111/j.1432-1033.1987.tb11209.x.
The conditions for coreconstitution of a bacterial ATP synthase and bacteriorhodopsin into lecithin liposomes and for light driven ATP synthesis have been optimized. A rate of maximally 280 nmol ATP min-1 mg ATP synthase-1 was achieved with monomerized bacteriorhodopsin compared with a rate of up to 45 nmol ATP min-1 mg-1 found for proteoliposomes containing bacteriorhodopsin in the form of purple membrane patches. The different rates are explained by the finding that monomeric bacteriorhodopsin is more homogeneously distributed among the liposomes than the purple membrane patches. The final activities depended on both the purification method for the two proteins and the coreconstitution procedure. Furthermore, the ratio (lipid to bacteriorhodopsin to ATP synthase) could be optimized. Light-driven ATP synthesis depends also on the type of detergent used. The best result was obtained by deoxycholate. Also the relationship between proton translocation (by bacteriorhodopsin) and ATP synthesis activity was measured. A constant H+/ATP ratio was found at higher light intensities. This ratio increased strongly at lower light intensities.
已对将细菌ATP合酶和细菌视紫红质构建到卵磷脂脂质体中以及光驱动ATP合成的条件进行了优化。与含有呈紫色膜片形式的细菌视紫红质的蛋白脂质体中高达45 nmol ATP min⁻¹ mg⁻¹的速率相比，单体化细菌视紫红质实现的最大速率为280 nmol ATP min⁻¹ mg ATP合酶⁻¹。不同的速率是由于发现单体细菌视紫红质在脂质体中的分布比紫色膜片更均匀。最终活性取决于两种蛋白质的纯化方法和构建过程。此外，（脂质与细菌视紫红质与ATP合酶的）比例可以优化。光驱动的ATP合成也取决于所用去污剂的类型。脱氧胆酸盐获得了最佳结果。还测量了（由细菌视紫红质进行的）质子转运与ATP合成活性之间的关系。在较高光强度下发现了恒定的H⁺/ATP比率。在较低光强度下该比率大幅增加。
