Effect of. Oxygen and Carbon Dioxide on the Mitochondria of Sclerotium Rolfsh

Abstract

The number of mitochondria apparently vary with the energy requirements of the cell (see Rouiller 1960). Although swelling and multiplication of mitochondria have been observed to occur in cells, a quantitative analysis of these changes has not been recorded. Matile and Bahr (1968) have recently provided electron micro-scopic evidence of the heterogeneity of density, mass, and volume of the mitochon-drial population in respiring baker's yeast. There are reports in the literature of the complete absence of mitochondria in yeast cells growing under anaerobic conditions (see Marchant and Smith 1968). Griffin and Nair (1968) demonstrated that the growth of Sclerotium rolfsii was inhibited by concentrations of oxygen below 4% and by concentrations of carbon dioxide above 0·03 %. It was, therefore, thought worthwhile to study the changes in mitochondria of this fungus when the cells are subjected to external stresses of low oxygen and high carbon dioxide levels.