Collective aspects of conformons and the electron transfer chain

The bhopalator: a molecular model of the living cell based on the concepts of conformons and dissipative structures

A molecular model of the living cell has been formulated based on a new theory of enzymic catalysis which takes into account the complementary roles of free energy and genetic information. The elementary units of free energy and genetic information that are necessary and sufficient for effectuating molecular mechanisms responsible for the life of the cell are called conformons. Conformons are visualized as a collection of a small number of catalytic residues of enzymes or segments of nucleic acids that are arranged in space and time with appropriate force vectors so as to cause chemical transformations or physical changes of a substrate or a bound ligand. So defined, conformons provide a plausible molecular means to link the genetic information stored in DNA and its ultimate expression, namely networks of coupled intracellular biochemical reactions and physical processes maintained by a continuous dissipation of free energy--dissipative structures of Prigogine. The proposed model of the living cell appears to possess the potential for bridging the gap between molecular biology and the biology of multicellular systems.

Physical basis of charge pairing in mitochondria

The postulate of charge pairing in the mitochondrial inner membrane is justified by applying a formula due to Fuoss to calculate the probability density for the distance between a positive and a negative charge. For dielectric constants 10 or less pairing is absolute, for 20 there is some tendency towards pairing, and at 78 it is nonexistent. Pairing, partner exchange or charge substitution, inhibition, and antiport uncoupling can be rationalized within this framework.

Theory of rate processes and the compensation rule

The rate of intermolecular charge transfer as involved in the theory of rate processes is derived for a quadratic generalization of Holstein's one-dimensional linear polaron theory. The activation energy and the activation entropy are shown to be proportional to the number of vibrational degrees of freedom associated with each molecular site. The activation entropy is found to be negative in this model, thus decreasing the reaction rate. A spin-polaron model is introduced where the electron is coupled in a specific way to N spins at each site. In this model both the activation parameters are positive and are proportional to N. Thus, the oscillator model gives a negative and the spin model gives a positive compensation temperature.