Valetti F, Sadeghi S J, Meharenna Y T, Leliveld S R, Gilardi G
Department of Biochemistry, Imperial College of Science, Technology and Medicine, London, UK.
Biosens Bioelectron. 1998 Sep 15;13(6):675-85. doi: 10.1016/s0956-5663(98)00021-9.
This work demonstrates that non-physiological electron transfer (ET) can occur in solution between wild type D. vulgaris flavodoxin (Fld) and horse heart cytochrome c (cyt-c), D. vulgaris cytochrome c553 (cyt-c553) and the haem domain of B. megaterium cytochrome P450 (cyt-P450 BMP). Second order rate constants of the ET reaction between [Fld]sq/[cyt-c]ox, [Fld]sq/[cyt-c553]ox and [Fld]sq/[cyt-P450 BMP]ox, were found to be 6.16 x 10(5), 1.80 x 10(4) and in the region of 10(5) respectively. These data are interpreted in terms of complementarity between the surfaces of the two proteins, their surface and redox potentials. Analysis of the ET results obtained from the separate wild type proteins supported the rational design approach in the creation of Fld-based chimeras. The preliminary design of the chimeras reported here is a 3D prototype for an artificial flavo-cytochrome obtained by covalent linkage of a Fld module to cyt-c553 via a disulphide bond. Theoretical ET rates calculated on the modelled flavo-cytochrome are encouraging the construction of these chimeric systems at DNA level. This work is now underway. The relevance of this molecular lego approach is to be seen in the long term goal of producing engineered multi-domain systems to be applied in the field of biosensors and bioelectronics to fulfil specific requirements. Novel catalytic devices can be obtained by using natural redox proteins in different combinations: this process mimics the natural evolution of proteins such as gene shuffling and gene fusion.
这项工作表明，非生理性电子转移（ET）可以在溶液中野生型普通脱硫弧菌黄素氧还蛋白（Fld）与马心细胞色素c（cyt-c）、普通脱硫弧菌细胞色素c553（cyt-c553）以及巨大芽孢杆菌细胞色素P450（cyt-P450 BMP）的血红素结构域之间发生。[Fld]sq/[cyt-c]ox、[Fld]sq/[cyt-c553]ox和[Fld]sq/[cyt-P450 BMP]ox之间ET反应的二级速率常数分别为6.16×10⁵、1.80×10⁴和10⁵左右。这些数据根据两种蛋白质表面之间的互补性、它们的表面和氧化还原电位进行了解释。对从单独的野生型蛋白质获得的ET结果的分析支持了基于Fld的嵌合体构建中的合理设计方法。本文报道的嵌合体的初步设计是一种人工黄素 - 细胞色素的三维原型，它是通过二硫键将Fld模块与cyt-c553共价连接而获得的。在模拟的黄素 - 细胞色素上计算的理论ET速率鼓励在DNA水平构建这些嵌合系统。这项工作正在进行中。这种分子积木方法的相关性将在生产工程化多结构域系统以应用于生物传感器和生物电子学领域以满足特定要求的长期目标中体现出来。通过以不同组合使用天然氧化还原蛋白可以获得新型催化装置：这个过程模仿了蛋白质的自然进化，如基因改组和基因融合。
