Phosphorylation energy hypothesis: open chemical systems and their biological functions.
Biochemical systems and processes in living cells generally operate far from equilibrium. This review presents an overview of a statistical thermodynamic treatment for such systems, with examples from several key components in cellular signal transduction. Open-system nonequilibrium steady-state (NESS) models are introduced. The models account quantitatively for the energetics and thermodynamics in phosphorylation-dephosphorylation switches, GTPase timers, and specificity amplification through kinetic proofreading. The chemical energy derived from ATP and GTP hydrolysis establishes the NESS of a cell and makes the cell--a mesoscopic-biochemical reaction system that consists of a collection of thermally driven fluctuating macromolecules--a genetically programmed chemical machine.
Qian
Hong
H
Department of Applied Mathematics, University of Washington, Seattle, WA 98195, USA. qian@amath.washington.edu
D007700:Kinetics; D008954:Models, Biological; D008956:Models, Chemical; D010766:Phosphorylation; D011506:Proteins / Q000737:chemistry / Q000378:metabolism; D013816:Thermodynamics
D011506:Proteins