Mosaic nonequilibrium thermodynamics

Another attempt to overcome the phenomenological character of nonequilibrium thermodynamics is called mosaic nonequilibrium thermodynamics. In the formulation of mosaic nonequilibrium thermodynamics, a complex system is considered a mosaic of a number of independent building blocks. The species and each process are separately described and hence the biochemical and biophysical structures of the system are included in the description. The mosaic nonequilibrium thermodynamics model can be expanded to complex physical and biological systems by adding the well-characterized steps. These steps obey the thermodynamic laws and kinetic principles. 

The theory of mosaic nonequilibrium thermodynamics has been applied to the following biological free-energy converters (Westerhoff and Dam, 1987)  

The terms Lu, L0, and are the transport coefficients for proton, oxygen, and ATP flows, respectively. The y factors 

The mosaic nonequilibrium thermodynamics approach was also used for studying microbial growth. In a simple configuration, aerobic microbial metabolism is considered a combination of three elemental steps that are mutually 

---

In mosaic nonequilibrium thermodynamics formulations not all the flows are dependent on all the fiee-energy differences, mainly because only a subset of catalytic components affects each flow relation. In this respect, the models differ from classical nonequilibrium thermodynamics where all flows are a function of all forces. 

The mosaic nonequilibrium thermodynamics formulation of oxidative phosphorylation uses the chemiosmotic model as a basis, besides assuming that the membrane has certain permeability to protons, and that the ATP synthase is a reversible pump coupled to the hydrolysis of ATP. It is assumed that the reversibility of the reactions allows the coupled transfer of electrons in the respiratory chain for the synthesis of ATP, and the proton gradient across the inner mitochondrial... 

The terms L, Lq, and Tp are the transport coefficients for proton, oxygen, and ATP flows, respectively. The y factors describe the enzyme-catalyzed reactions with the rates having different sensitivities in the change of free energy for the proton pump and other reactions. This differential sensitivity is a characteristic of the enzyme and is reflected by the mosaic nonequilibrium thermodynamics formulation of the flow-force relationships of that enzyme. The term h shows the number of protons translocated per ATP hydrolyzed, while Jh, Jq, and Jp indicate the flows of hydrogen, oxygen, and ATP, respectively. 

---