二氧化碳跨生物膜的传递机制研究进展

二氧化碳(CO₂)作为生物体内的代谢产物和反应底物,其与外界环境的气体交换是保证生物体正常生命活动的重要基础。CO₂在生物体尤其是细胞内的传递对于控制碳排放、构建高效碳循环、开发新型碳捕集技术具有重要意义。本文对生物体内CO₂的传递机制进展进行了综述,重点介绍了CO₂跨膜运输的不同方式与相应机制,针对水通道蛋白对CO₂的促进传递作用进行了较为详细的分析,指出在膜对CO₂自渗透性低时水通道蛋白对CO₂的跨膜运输才能发挥重要作用。近期研究进展表明,水通道蛋白四聚体的中央孔道和水通道赋予其对CO₂的促进传递作用。此外,碳酸酐酶和HCO₃^–-Cl^–转运蛋白的存在能加速细胞内酸化过程,提高CO₂的传递速率。期望本综述能够为开发新的仿生膜材料及其碳捕集技术提供理论方面的一些参考。

Research progress on the transfer mechanisms of CO2 across biological membranes

CO₂,as a vital metabolic product and reaction substrate in living organisms,can make gas exchange with external environment,which is crucial to ensure the normal physiological activities of living organisms. The transfer of CO₂ in organisms,especially in cells,is of great significance for controlling the emission of CO₂,constructing efficient carbon cycle and exploring the carbon capture technology. This review presents a brief overview of the research progress on CO₂ transport mechanisms in organisms,including the detailed analysis of different models about the CO₂ transmembrane transport mechanisms,and in particular the facilitated transport of CO₂ by aquaporin protein,with the conclusion that the aquaporin-mediated CO₂ permeation plays an important role in membrane with a low intrinsic CO₂ permeability. Recent researches also show that the water channels and central pore along the fourfold axis of the tetramer of aquaporin are supposed to function in the CO₂ transmembrane transport. Moreover,the existence of carbonic anhydrase and HCO₃^–-Cl^– transporter can accelerate intracellular acidification process,thus increase the CO₂ transmembranetransport rate. This review could offer theoretical reference for developing new biomimetic membrane materials and carbon capture technology.