Protein Electron Transfer: Gating and Dynamics.

无机化学、生物无机化学和金属有机化学项目的这一奖项支持蒙大拿大学的布鲁斯·E·鲍勒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。被研究的模型体系是基于细胞色素c(Cytc)的碱性构象。ET门控的速率和涉及门控的构象变化的速率将被独立测量，并将评估构象变化的热力学。在iso-1-Cytc模型体系中，门控ET的速率将通过(1)改变组氨酸配体在由碱性构象展开的表面环中的位置作为一种扩展可用的门控速率范围的手段来确定，(2)引入Phe 82的取代以微调His 73-血红素碱性构象的100 ms门控速率，以及(3)用Gly取代Pro 76以简化ET门控动力学。还将探讨52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位的表面环的动力学。将在iso-1-Cytc模型系统中开发用于光导门控ET的衬底。这些研究将为蛋白质中影响电子转移的因素提供基本的见解，并为基于蛋白质的分子电子器件提供实用策略。该研究为本科生和研究生提供独立的前沿研究项目。因此，在这个项目中接受培训的学生将为走向新兴的分子电子学领域做好准备。

This award in the Inorganic, Bioinorganic and Organometallic Chemistry program supports research by Professor Bruce E. Bowler at the University of Montana 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.