振动强耦合体系中溶剂–离子协同效应对ATP水解的调控作用

Modulation of ATP Hydrolysis Kinetics by Solvent-Ion Synergy in a Vibrational Strong Coupling Regime

摘要: 振动强耦合(vibrational strong coupling, VSC)通过溶剂–离子–光子协同作用重塑三磷酸腺苷(adenosine triphosphate, ATP)水解动力学。通过将法布里–珀罗腔与水的O-H振动(3404 cm⁻¹)耦合，我们发现，在富含Ca²⁺的磷酸盐缓冲液中，VSC使水解速率提升2.4倍，优于纯水体系(1.6倍)。Ca²⁺通过中和ATP磷酸基团的负电荷减少静电排斥，同时VSC诱导的振动杂化(拉比分裂能735 cm⁻¹)通过重构氢键网络优化质子传递路径，二者协同优化了酶–底物结合构象。红外光谱研究表明，VSC重构了氢键网络，优化了质子转移。这一“溶剂–离子–振动强耦合”三元模型为光控酶工程开辟了新途径，可应用于高效生物能源系统及纳米医学。

Abstract: Vibrational strong coupling (VSC) reshapes adenosine triphosphate (ATP) hydrolysis kinetics through solvent-ion-photonic synergy. Using a Fabry-Pérot cavity coupled to water’s O-H vibration (3404 cm⁻¹), we reveal that VSC in Ca²⁺-enriched phosphate-buffered saline (PBS) boosts hydrolysis rates by 2.4-fold, outperforming pure water (1.6-fold). Ca²⁺ mitigate electrostatic repulsion by neutralizing the negative charges on ATP’s phosphate groups. Concurrently, VSC induces vibrational hybridization—evidenced by a Rabi splitting energy of 735 cm⁻¹, which reconstructs the hydrogen-bond network and facilitates proton transfer. This synergistic effect between Ca²⁺ and VSC optimizes the enzyme-substrate binding conformation. Infrared spectroscopy confirms that VSC reorganizes the hydrogen-bonding landscape to promote efficient proton transfer. This integrated “solvent-ion-VSC” triad model offers a novel strategy for light-regulated enzyme engineering and holds promise for applications in high-efficiency bioenergy systems and nanomedicine.