DPNH oscillations in glycolyzing cell free extracts from beef heart

Abstract

The oscillatory responses of reduced pyridine nucleotide in Saccharomyces carlsbergensis have been the object of considerable attention ( Chance et al., 1964a, 1964b). The oscillations, first observed in intact cell suspensions, have also been obtained in cell free extracts from the same yeast strain ( Chance et al., 1964c, 1964d, 1965). The sensitivity of the oscillations to iodoacetic acid led to the conclusion that DPN, rather than TPN, was the nucleotide involved. ( Chance et al., 1964c). The assay of glycolytic intermediates and adenine rucleotides in the oscillating cells has also demonstrated oscillations in these intermediates, each having a definite phase relationship with reduced pyridine nucleotide ( Ghosh and Chance 1964; Betz and Chance, 1965a, 1965b). This communication reports some results that have been obtained with glycolyzing cell free extracts from beef heart. These preparations have shown cyclic oscillations of reduced pyridine nucleotide in a manner similar to that obseved in yeast extracts.