Protein Electron Transfer: Gating and Dynamics.

这个无机、生物无机和有机金属化学项目的奖项支持丹佛大学的Bruce E. Bowler教授研究蛋白质中电子转移（ET）反应的门控和动力学的基本方面。所研究的模型体系是基于细胞色素c （Cytc）的碱性构象。我们将分别测量ET的门控速率和门控过程中构象变化的速率，并对构象变化的热力学进行评估。在iso-1-Cytc模型系统中，门控ET的速率将通过(1)改变组氨酸配体在碱性构象展开的表面环中的位置来确定，这是延长门控速率范围的一种方法，(2)引入Phe 82的替代品来调整His 73-血红素碱性构象的100 ms门控速率，(3)用Gly取代Pro 76来简化ET门控动力学。还将探讨52位和67位突变对电子耦合的影响，这些突变调节了Cytc中从40位到57位的表面环路的动力学。将开发iso-1-Cytc模型系统中光诱导门控ET的衬底。这些研究将为蛋白质中影响电子转移的因素和基于蛋白质的分子电子器件的实用策略提供基本的见解。该研究为本科生和研究生提供了独立的前沿研究项目。因此，在这个项目中训练的学生将准备走向新兴的分子电子学领域。

This award in the Inorganic, Bioinorganic and Organometallic Chemistry program supports research by Professor Bruce E. Bowler at the University of Denver to investigate fundamental aspects of gating and dynamics of electron transfer (ET) reactions in proteins. The model system to be investigated is based on the alkaline conformer of cytochrome c (Cytc). The rate of ET gating and the rate of the conformational change involved in gating will be measured independently and the thermodynamics of the conformational change will be assessed. Rates of gated ET in the iso-1-Cytc model system, will be determined by (1) varying the position of the histidine ligand in the surface loop unfolded by the alkaline conformer as a means of extending the range of gating rates available, (2) introducing substitutions for Phe 82 to fine-tune the 100 ms gating rate of the His 73-heme alkaline conformer and (3) replacing Pro 76 with Gly to simplify ET gating kinetics. The effect on electronic coupling by mutations at positions 52 and 67, which modulate the dynamics of the surface loop running from positions 40 to 57 in Cytc will also be probed. Substrates for photoinducible gated ET in the iso-1-Cytc model system will be developed. These studies will provide fundamental insight into the factors that affect electron transfer in proteins and practical strategies for protein-based molecular electronics devices. The research provides undergraduate and graduate students with independent forefront research projects. Consequently, the students trained in this project will be primed to move toward the emerging field of molecular electronics.