A comparative study of pyridine nucleotide metabolism in yeast and mammalian cells by microfluorimetry-microelectrophoresis.

Abstract

1. The microfluorimetric-microelectrophoretic technique which was initially used in irradiated and non-irradiated tissue culture ascites cells (EL2 cells) for the exploration of metabolic compartments and control mechanisms has been extended now to other cell types such as: chinese hamster cells, mesenchymal cells grown from brown fatty tissue of newborn rats, human liver cells in culture and hexaploid yeast. 2. A typical model in which two metabolically divergent cells are brought to almost equality by inhibitors is seen in comparative experiments between non-irradiated EL2 cells (EL2SG) and X-ray produced EL2 giants (EL2G). Although the glycolytic responses of the EL2 G are much more intense than those of the EL2 SG, after treatment with Dicumarol and Rotenone these two cell types differ very little. 3. These experiments revealed common sets of responses, such as the selective localization of glycolytic events in the extramitochondrial space for all cell types investigated. Nonirradiated Chang cells, EL2 and chinese hamster cells in aerobic condition show all a weak response or no response to glycolytic intermediates, but considerable potentiation of these responses in presence of Rotenone. X-ray produced EL2 and Chang giants show a more active glycolytic response at aerobiosis and a lesser Rotenone-sensitivity than their non-irradiated counterparts. 4. So far the nuances observed in the fluorescence behaviour of various cell types treated with metabolites allows their grouping in five categories: non-irradiated cells responding to G6P only in presence of Rotenone, Chinese hamster and Chang cells; cells responsive to G6P in aerobic condition, but with response further enhanced by inhibitors such as Dicumarol and Rotenone (EL2SG); irradiated cells responsive to G6P in aerobic condition and little influenced by Rotenone (Chang giant); same as preceding but with more intense G6P response; (EL2G) and non-irradiated microorganisms behaving like irradiated giants (hexaploid yeast).