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E H Battley

Publications and source records attributed to E H Battley.

6 recordsLinked to original sources
PubMed1979

Alternate method of calculating the free-energy change accompanying the growth of saccharomyces cerevisiae (Hansen) on three substrates.

A method is described for determining the free energy of formation of the cells of Saccharomyces cerevisiae (Hansen) that are formed as the result of anaerobic growth on glucose, and aerobic growth on glucose and ethanol. The method is based on the direct relationship that exists between the enthalpy changes and the free-energy changes that accompany the oxidation of 1 g cellular material formed during these growth reactions and the degree of reduction of the same material. When the results of these calculations are used together with the free energies of formation of the reactants and of other products of a given growth reaction, it becomes possible to calculate the free-energy change accompanying this reaction. These free-energy changes are in excellent agreement with those calculated by another method based on the hypothesis that the free-energy change accompanying the conversion of the substrate plus other reactants into cellular material plus other products is equal to zero.

Aerobiosis↗
PubMedDate not supplied

A reevaluation of the thermodynamics of growth of Saccharomyces cerevisiae on glucose, ethanol, and acetic acid.

Statistically determined values for the free energy and enthalpy change per equivalent accompanying the combustion of organic substances have been used to test the hypothesis that the free energy, enthalpy, and entropy changes accompanying anabolism are zero or nearly so. It is found that while this can be true in some cases, it is not always so, because the free energy and entropy changes per available electron accompanying biological combustion are different for different small molecular weight substrates although they are constant for cellular biomass. If the average energy change per equivalent accompanying the biological combustion of the cells is markedly different from that of the substrate, there will be a corresponding change in energy accompanying anabolism that is determined by the difference between them. The efficiency of available electron conservation is proposed as being preferable to free energy, enthalpy, and entropy efficiencies in that the latter parameters all have different values, whereas the former is common to all three of the latter. Free energy, enthalpy, and entropy efficiencies can be calculated from available electron conservation efficiencies if the biological combustion energies of the substrate, cells, and products are known per electron transferred. The methods described are applicable equally to aerobic and anaerobic growth process systems.

Acetates↗