Enzyme-level molecular simulation-assisted screening of functional bacteria for rapid bioelectrochemical sensing

Biochemical oxygen demand (BOD) is a key indicator of organic pollution in aquatic environments, and its rapid and accurate determination is crucial for monitoring and controlling the quality of water. Microbial fuel cell -based BOD sensing has attracted increasing attention; however, the limited electron transfer capability of microorganisms restricts the speed of sensor response. This study proposes an integrated framework combining molecular dynamics (MD) simulations and molecular docking for the detection of highly electroactive microorganisms. Hexokinase enzymes form stable complexes with glucose through hydrogen bonds and carbon-hydrogen bonds. During simulations, these complexes exhibit stable conformational changes and demonstrate optimal affinity and binding capacity. The mechanisms of electron generation and transfer were further analyzed in conjunction with electrochemical performance. Following implementation of this strategy and conduct of experiments, the results demonstrated that the sensor's response time was reduced to 10 min, representing a 50 % improvement over the previous measurements. The detection range was established at 73.3-440.0 mg/L. Furthermore, a strong correlation was exhibited between BOD concentration and actual performance (R² = 0.987), which fully confirms the sensor's rapid responsiveness and high accuracy for the detection of BOD. This work accelerates sensor response and introduces a novel framework of enzyme-level MD simulation for optimizing strain selection and provide an effective strategy for real-time BOD monitoring.