PT  - JOURNAL ARTICLE
AU  - Jorge Fernandez-de-Cossio-Diaz
AU  - Alexei Vazquez
TI  - A physical model of cell metabolism
AID  - 10.1101/209551
DP  - 2017 Jan 01
TA  - bioRxiv
PG  - 209551
4099  - http://biorxiv.org/content/early/2017/10/26/209551.short
4100  - http://biorxiv.org/content/early/2017/10/26/209551.full
AB  - Cell metabolism is characterized by three fundamental energy demands to sustain cell maintenance, to trigger aerobic fermentation and to achieve maximum metabolic rate. Here we report a physical model of cell metabolism that explains the origin of these three energy scales. Our key hypothesis is that the maintenance energy demand is rooted on the energy expended by molecular motors to fluidize the cytoplasm and counteract molecular crowding. Using this model and independent parameter estimates we make predictions for the three energy scales that are in quantitative agreement with experimental values. The model also recapitulates the dependencies of cell growth with extracellular osmolarity and temperature. This theory brings together biophysics and cell biology in a tractable model that can be applied to understand key principles of cell metabolism.