EAGER: Quantum-coherent transport in bacterial protein nanowires

该项目旨在评估量子相干在细菌生长、呼吸和通信中的作用。该项目的PI发现，常见的土壤细菌已经进化出金属蛋白纳米线，以消除新陈代谢产生的电子。纳米线允许细菌在恶劣的环境中生存，这些环境缺乏氧气等膜透过性电子受体。这一发现表明，一种独特的量子材料，表现出类似金属的性质，具有理论预测的电子相干和量子相干电子转移，可以用光进一步加速。令人惊讶的是，这种相干性在极端的水和酸性环境中仍能保持。了解是什么使这种相干在无序和噪声面前茁壮地生存，将有助于设计细菌群落，这些细菌群落可以：保持相干以加速电荷运输，自主优化它们在不断变化的环境中的表现，以及感觉和信号损伤以启动自我修复。PIS将把这项研究整合到针对各级学生的一系列教育和推广活动中，利用这项多学科研究作为一种工具，加强对学生的招生、保留、教育和培训，并通过利用我们现有的基础设施来提高多样性和包容性，关注那些来自代表性不足的群体。PIS将为蛋白质纳米线的量子性质开发新的合成、表征和建模系统。通过表征电子、离子、激子和手性诱导的高度极化的自旋在纳米线中的传输，以惊人的超快速度和厘米距离，PI将量化自旋松弛、扩散长度以及相干长度和时间，以阐明设计原则和机制。该项目由生物科学部门分子和细胞生物科学司分子生物物理学集群支持。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The project seeks to evaluate the role of quantum coherence in bacterial growth, respiration and communication. The PIs of this project have discovered that common soil bacteria have evolved metalloprotein nanowires to get rid of electrons derived from metabolism. The nanowires allow bacteria to survive in harsh environments that lack membrane-permeable electron acceptors such as oxygen. This discovery suggests a unique quantum material, exhibiting metal-like properties, with theoretically-predicted electronic coherence, and quantum-coherent electron transfer, that can be further accelerated with light. Surprisingly, the coherence is preserved under extreme aqueous and acidic environments. Understanding what makes this coherence robust to survive in the face of disorder and noise will help in designing bacterial communities that can: preserve coherence to accelerate charge transport, autonomously optimize their performance in changing environments as well as sense and signal damage to initiate self-repair. The PIs will integrate this research into a range of educational and outreach activities for students at all levels by using this multidisciplinary research as a vehicle to enhance recruitment, retention, education, and training of students, with attention to those from underrepresented groups by leveraging our existing infrastructure to enhance diversity and inclusion.The PIs will develop new systems of synthesis, characterization, and modeling for quantum properties of protein nanowires. By characterizing transport of electrons, ions, excitons, and chirality-induced, highly-polarized spins in nanowires, at surprising ultrafast rates and centimeter distances, the PIs will quantify the spin relaxation, diffusion length as well as coherence length and time to elucidate design principles and mechanisms.This project is supported by the Molecular Biophysics Cluster of the Division of Molecular and Cellular Biosciences in Biological Sciences Directorate.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.