A physical model of cell metabolism

Cell metabolism involves distinct energy demands, yet the origin of maintenance energy remains unexplained. Established knowledge includes enzymatic cost constraints for aerobic fermentation and maximum metabolic rate. This paper introduces a novel hypothesis about maintenance energy. Prior research has shown that molecular crowding affects cellular function. No prior work had resolved the physical basis of maintenance energy. This gap motivated a new theoretical approach. The model integrates biophysics and cell biology. It offers a framework to understand energy scales in cells. This paper's contribution is a physical explanation for maintenance energy.

This study aims to explain the origin of three energy demands in cell metabolism. The focus is on the maintenance energy demand. The authors propose a physical model to address this gap. They hypothesize that maintenance energy arises from molecular motors. These motors fluidize the cytoplasm and counteract crowding. The model predicts energy scales matching experimental data. The purpose is to unify biophysics and cell biology. This approach provides a new perspective on metabolic energy.

The researchers developed a physical model of cell metabolism. They focused on cytoplasmic fluidization by molecular motors. The model uses independent parameter estimates. It incorporates energy expenditure from molecular motors. The model predicts three energy scales. These predictions align with experimental values. The model also explains growth dependencies on osmolarity. It accounts for temperature effects on cell growth.

The model predicts maintenance energy from molecular motor activity. Predictions match experimental values for energy scales. The model explains the transition to aerobic fermentation. It also accounts for maximum metabolic rate. Growth dependencies on osmolarity are captured. Temperature effects on growth are also explained. The model integrates biophysics with cell biology. It provides a quantitative framework for metabolic energy.

The authors propose that maintenance energy stems from molecular motors. The model aligns with experimental data on energy scales. It explains growth dependencies on osmolarity and temperature. The model bridges biophysics and cell biology. It offers a tractable framework for metabolic energy. The theory suggests fluidization as a key mechanism. The model can be applied to understand cell metabolism. It provides a new perspective on energy demands.