以高疏水性大米蛋白为例的多物理场耦合胁迫对蛋白质高级结构及功能的作用机制

大米蛋白极具营养特性及生物相容性，但其疏水性属植物蛋白之首。我们已发现，大米蛋白经离子胁迫导致的溶融态（MG）转变后，机械胁迫可保持其一级结构的同时，显著提高其溶解性。为此，基于多物理场耦合胁迫的增效作用，深入探讨多重物理场胁迫对大米蛋白构象及功能的影响机制：（1）在离子液体营造的高质子活力环境中，实施微通道胁迫，形成蛋白质小聚体，揭示离子液体胁迫-微通道胁迫影响MG结构的分子学机制；（2）以溶剂晶体作为能量传递介质，搭建外来机械能做功于蛋白质小聚体构象的分子梯，揭示离子液体胁迫-微通道胁迫-分子梯机械胁迫改变大米蛋白高级结构的作用机理；（3）建立并验证多物理场耦合胁迫与蛋白质构象变化的结构层次和程度间的数学模型，以实现大米蛋白功能性改善的定向定量设计。本项目将建立多物理场耦合胁迫改性大米蛋白高级结构的理论机制和技术方法，也可为其它疏水性蛋白质的高级结构物理改性研究提供新的理论和途径。

Rice proteins, with extremely high nutritional and biocompatible value, are among the most hydrophobic proteins. For the first time, our group prepared rice proteins with high solubility but intact molecular integrity by imposing multi-field coupling stresses, i.e., molten globule transition by ionic stress followed by mechanical stresses of different origin. In this proposal, we aim to unveil the synergistic effects of these physical stresses by investigating: (1) the relationship between proton activity (PA) and the degree of MG transition, as well as the molecular basis of disaggregation of rice proteins induced by micro-fluidization; (2) the effects of ionic stress-micro-fluidization stress-molecular ladder mechanical stress on the sub-aggregates of rice proteins based on the molecular ladder formed by phase transition of the solvents; (3) the targeted design of modified rice proteins with tunable functionalities based on the establishment of a mathematical model describing the relationship between the strength of multi-field coupling stresses and the degree of structural modifications. Meanwhile, the research will lay the theoretical and technical foundations of protein modifications under multi-field coupling technique.