Chirality-Induced Spin Selectivity in Biology:The Role of Spin-Polarized Electron Current in Biological Electron Transport & Redox Enzymatic Activity

生物学中手性诱导的自旋选择性：自旋极化电子流在生物电子传输中的作用

基本信息

批准号：
BB/X002810/1
负责人：
Ismael DIEZ PEREZ
金额：
$ 57.93万
依托单位：
King's College London
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2023
资助国家：
英国
起止时间：
2023 至无数据
项目状态：
未结题

来源：
https://gtr.ukri.org/projects?ref=BB%2FX002810%2F1
关键词：
Chirality Induced Spin Selectivity Biology

项目摘要

Quantum mechanics is the fundamental theory that describes the behaviour of nanoscale systems. In the past three decades, we have seen a growing number of manifestations of quantum mechanical effects in a variety of biomolecular systems connected to essential biological functions. In photosynthesis, long-lived vibrational coherences have been detected for light-harvesting photosynthetic complexes. Such unexpected long-living quantum coherence at room temperature confers remarkable energy transfer efficiencies to natural photosynthetic complexes. In avian navigation, photo-generation of a radical pair inside a cryptochrome protein is exploited as a mechanism of magnetoreception. The time the radical pair stays in a singlet (inactive) or a triplet (active) spin state is influenced by the direction of the weak terrestrial magnetic field. This is exploited as a precise compass in many bird species and plants. The above mentioned radical pair mechanism offers also scientific foundations to explain the production and control of Reactive Oxygen Species (ROS), with essential roles in cell signalling and homeostasis.The above cases provide a quick survey of examples in the emerging field of Quantum Biology, which extends to other very different areas such as olfaction, cognition, DNA oxidative damage, etc. The most striking point in all the above examples is not just the manifestation of quantum mechanics itself, which arises when studying the biological system down to the molecular level, but in how nature has evolved to control such molecular-scale processes to fulfil vital functions. Understanding how nature orchestrate quantum mechanical processes to its advantage is of much relevance to the current quantum technology era.The above examples have taught us about the unexpected important role of the electronic spin in biological processes. This project proposes to study a new quantum biological effect based on the electron spin whose impact extends to all chiral redox biomolecular systems. The key underlying mechanism is based on the Chirality-Induced Spin Selectivity (CISS), which refers the inherent ability of chiral molecular structures to select one particular component of electronic spin, thereby leading to spin polarization. When an electric current flows through a chiral molecular system, the transient electrons experience a degree of spin polarization similar to what occurs in a standard magnetic device under applied magnetic fields. The CISS effect presents two essential ingredients relevant to biology; (1) it occurs at room temperature and (2) operates in the absence of external magnetic fields. The translation of the CISS effect into biology means a chiral peptide scaffold surrounding a redox co-factor acts as a "smart matrix" which magnetically prepares the spin of the crossing electrons going into the redox centre.Our working team brings a unique theoretical-experimental approach combining advanced single-peptide/protein electrical characterization and the latest developments in the theory of spin-polarized electron transport. Using this synergistic approach, this consortium has already demonstrated exceedingly large electron spin polarization (>60%) in an individual 3 nanometres long alpha-helical peptide sequence trapped in a controlled nanoscale gap immersed in a physiological medium. This project builds upon these outstanding results to (1) generate an atomistic picture of the CISS effect in a helical peptide, (2) quantify the impact of (1) in the charge transport across a redox protein, and (3) study the CISS effect on a redox enzymatic reaction. We anticipate our results will open a new area in quantum biology bringing fundamental knowledge to biological redox chemistry relevant to disease mechanisms and bioenergy. This knowledge transcends the biological arena bringing revolutionary solutions to the design of new materials and applications in quantum information.

量子力学是描述纳米级系统行为的基础理论。在过去的三十年中，我们在与基本生物功能相关的各种生物分子系统中看到了越来越多的量子力学效应的表现。在光合作用中，已检测到光捕获光合复合物的长寿命振动相干性。这种在室温下出人意料的长寿命量子相干性为自然光合作用复合物带来了显着的能量转移效率。在鸟类导航中，隐花色素蛋白内自由基对的光生成被用作磁感受机制。自由基对保持单重态（不活跃）或三重态（活跃）自旋状态的时间受到弱地磁场方向的影响。许多鸟类和植物都将其用作精确的指南针。上述自由基对机制还为解释活性氧（ROS）的产生和控制提供了科学基础，其在细胞信号传导和体内平衡中发挥着重要作用。上述案例提供了对量子生物学新兴领域的示例的快速调查，延伸到其他非常不同的领域，如嗅觉、认知、DNA氧化损伤等。上述所有例子中最引人注目的一点不仅仅是量子力学本身的表现，它在研究生物系统直至分子时出现水平，而是自然如何进化以控制这种分子尺度的过程来实现重要功能。了解大自然如何协调量子力学过程以发挥其优势，与当前的量子技术时代密切相关。上述例子告诉我们电子自旋在生物过程中意想不到的重要作用。该项目提议研究一种基于电子自旋的新量子生物效应，其影响延伸到所有手性氧化还原生物分子系统。关键的潜在机制基于手性诱导自旋选择性（CISS），它是指手性分子结构选择电子自旋的一种特定成分的固有能力，从而导致自旋极化。当电流流过手性分子系统时，瞬态电子会经历一定程度的自旋极化，类似于标准磁性装置在施加磁场下发生的情况。 CISS 效应呈现出与生物学相关的两个基本要素： (1) 它发生在室温下，(2) 在没有外部磁场的情况下工作。将 CISS 效应转化为生物学意味着围绕氧化还原辅因子的手性肽支架充当“智能矩阵”，以磁性方式准备进入氧化还原中心的交叉电子的自旋。我们的工作团队带来了独特的理论实验该方法结合了先进的单肽/蛋白质电学表征和自旋极化电子传输理论的最新发展。利用这种协同方法，该联盟已经在浸入生理介质的受控纳米级间隙中捕获的单个 3 纳米长的 α 螺旋肽序列中展示了极大的电子自旋极化 (>60%)。该项目以这些杰出成果为基础，(1) 生成螺旋肽中 CISS 效应的原子图，(2) 量化 (1) 氧化还原蛋白上电荷传输的影响，以及 (3) 研究 CISS对氧化还原酶促反应的影响。我们预计我们的结果将开辟量子生物学的新领域，为与疾病机制和生物能源相关的生物氧化还原化学提供基础知识。这些知识超越了生物领域，为新材料的设计和量子信息的应用带来了革命性的解决方案。