Heterotrophic Carbon Dioxide Fixation Products of Euglena

Abstract

The metabolic products of heterotrophic (dark) CO(2) fixation by Euglena gracilis Klebs strain Z Pringsheim were separated and identified. They consisted of amino acids, phosphorylated compounds, tricarboxylic acid cycle intermediates, and nucleotides. Exposure of the cells to NH(4) (+) after a period of NH(4) (+) deprivation stimulated heterotrophic CO(2) fixation almost 4-fold, modifying the spectrum of the fixation products. In particular, the NH(4) (+) treatment stimulated fixation of CO(2) into glutamine, glycine, alanine, and serine.