Hydrogen bonds are fundamental to the structure and function of biological macromolecules and have been explored in detail. The chains of hydrogen bonds (CHBs) and low-barrier hydrogen bonds (LBHBs) were proposed to play essential roles in enzyme catalysis and proton transport. However, high-resolution structural data from CHBs and LBHBs is limited. The challenge is that their ‘visualization’ requires ultrahigh-resolution structures of the ground and functionally important intermediate states to identify proton translocation events and perform their structural assignment. Our true-atomic-resolution structures of the light-driven proton pump bacteriorhodopsin, a model in studies of proton transport, show that CHBs and LBHBs not only serve as proton pathways, but also are indispensable for long-range communications, signaling and proton storage in proteins. The complete picture of CHBs and LBHBs discloses their multifunctional roles in providing protein functions and presents a consistent picture of proton transport and storage resolving long-standing debates and controversies.

氢键是生物大分子结构和功能的基础，并已被详细探索。氢键链（CHBs）和低势垒氢键链（LBHBs）被认为在酶催化和质子运输中发挥重要作用。然而，来自 CHB 和 LBHB 的高分辨率结构数据是有限的。挑战在于它们的“可视化”需要地面的超高分辨率结构和功能重要的中间状态来识别质子易位事件并执行它们的结构分配。我们的光驱动质子泵细菌视紫红质的真实原子分辨率结构是质子传输研究的模型，表明 CHB 和 LBHB 不仅作为质子通路，而且对于远程通信也是必不可少的，蛋白质中的信号传导和质子储存。CHBs 和 LBHBs 的全貌揭示了它们在提供蛋白质功能方面的多功能作用，并呈现了质子运输和储存的一致图景，解决了长期存在的争论和争议。