A Simple, Robust Biomimetic Charge Separation Protein Domain

这项研究涉及一种人造蛋白质的设计、合成和分析，这种蛋白质在短脉冲光的激发下能够产生相对较长寿命的电荷分离状态。电荷分离过程是光合作用的第一步，也是最重要的一步，这种结构将使研究人员能够检查支持电荷分离的潜在物理过程。该项目涉及设计一个三辅因子螺旋束蛋白结构域，该结构域通过三种正交机制结合其辅因子：主要供体分子将是锌(II)-酞菁，它与单组氨酸五配位位点特异性结合。受体辅因子结合位点为六配位双组氨酸位点，能与多种含铁大环紧密稳定结合。使用细胞色素C生物发生系统，供体位点将含有C型血红素共价附着在体内。该电荷分离结构域将共价连接到邻苯二甲酸酯双加氧酶还原酶的黄蛋白还原酶结构域，使供体能够通过简单添加NADH通过天然蛋白质嵌合体将电子转移到主要供体酞菁辅助因子上。预期的最终产品将是一个简单、坚固的模块化蛋白质结构域，它将为许多不同的科学家和工程师创造太阳能驱动设备提供服务。更广泛的影响这项工作不仅将提高对电荷分离工程的理解，还将产生一系列具有可调动力学和能量学的蛋白质结构域，这些结构域可用于光激活纳米器件的创建。CCNY是一所公立城市大学，拥有一个极其多元化的多民族学生群体。此外，还将制定向本科生、研究生和纽约市公立高中教师介绍交叉学科生物物理学的教育计划。

Intellectual MeritThis research concerns the design, synthesis and analysis of an artificial protein which will have the ability to create a relatively long-lived charge separated state when excited with short bursts of light. The process of charge separation is the first, most important step in photosynthesis, and this construction will allow researchers to examine the underlying physical processes which support charge separation. The project involves the design of a three cofactor helical bundle protein domain which binds its cofactors by three orthogonal mechanisms: the primary donor molecule will be a zinc(II)-phthalocyanine which binds specifically to mono-histidine pentacoordinate sites. The acceptor cofactor binding site will be a hexacoordinate bis-histidine site which tightly and stably binds a variety of iron-containing macrocycles. The donor site will contain a C-type heme covalently attached in vivo using the cytochrome C biogenesis system. This charge separation domain will be covalently attached to the flavoprotein reductase domain of phthalate dioxygenase reductase, enabling the donor to be poised for electron transfer to the primary donor phthalocyanine cofactor via the natural protein chimera by the simple addition of NADH. The intended final product will be a simple, robust modular protein domain which will serve many different scientists and engineers in their creation of solar energy-driven devices.Broader ImpactThis work will not only improve the understanding of the engineering of charge separation, it will result in a series of protein domains with tunable kinetics and energetics which can be used in the creation of light-activated nanodevices. CCNY, a public, city university, has an extremely diverse multi-ethnic student body. An educational plan, which introduces undergraduates, graduate students and New York City Public High School teachers to the interdisciplinary science of biophysics, will be developed.