Energy transducing processes, interaction between

The information about energy-transducing processes presented above shows that these systems do not operate independently, but that they are closely coupled. This interaction between primary and secondary transport systems, substrate level phosphorylation and biosynthetic processes is given in the following scheme ... 

In their work on oxidative phosphorylation in mitochondria, Baum et al.(1971) pioneered the use of double inhibitor titration of electron transfer reactions and of ATPase as an approach for the study of the interaction between energy transducers. In the chemiosmotic model, the coupling between two enzyme complexes is mediated by the "delocalized" protons, so that if one of the two transducers is kinetically limiting the overall rate, the inhibition of the other complex should not influence the overall velocity of the process. 

The bond graph in Figure 14.2 contains a dissipative coupling between flows A and B, in which only an interacting fraction is involved in the process. Therefore, the linear transducer TD, which converts energy from one form to another, thereby conserving power, is introduced into the bond graph. The operation of transducer is characterized by a modulus r, which may be a function of the parameter of state, such as temperature or concentration, and is independent of flows and forces. 

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