Regulation of Glycolytic Flux and Ethanol Production in Saccharomyces cerevisiae: Effects of Intracellular Adenine Nucleotide Concentrations on the In Vitro Activities of Hexokinase, Phosphofructokinase, Phosphoglycerate Kinase, and Pyruvate Kinase †

AUTOR(ES)

Alterthum, Flavio

RESUMO

The progressive decline in the glycolytic activity of Saccharomyces cerevisiae during batch fermentation is accompanied by changes in adenine nucleotide pools. The relative activities of four glycolytic enzymes were examined in vitro in the presence of nucleotide concentrations equivalent to intracellular pools. Phosphofructokinase and pyruvate kinase were not inhibited. Phosphoglycerate kinase was inhibited by AMP but was judged unlikely to be of physiological consequence owing to enzyme abundance. Both isoenzymes of hexokinase were strongly inhibited by AMP. The degree of hexokinase inhibition was sufficient to account for the observed decline in glycolytic activity during batch fermentation.

Documentos Relacionados

• Organization and nucleotide sequences of the Spiroplasma citri genes for ribosomal protein S2, elongation factor Ts, spiralin, phosphofructokinase, pyruvate kinase, and an unidentified protein.
• Ethanol production during batch fermentation with Saccharomyces cerevisiae: changes in glycolytic enzymes and internal pH.
• Identification of a novel operon in Lactococcus lactis encoding three enzymes for lactic acid synthesis: phosphofructokinase, pyruvate kinase, and lactate dehydrogenase.
• Effects of Pyruvate Decarboxylase Overproduction on Flux Distribution at the Pyruvate Branch Point in Saccharomyces cerevisiae
• Glycolytic Flux and Hexokinase Activities in Anoxic Maize Root Tips Acclimated by Hypoxic Pretreatment.