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Assimilation of acetate and its enhancement by light was investigated in the green alga, Chlamydomonas mundana. The increase of both acetate assimilation and respiration appears related to photosynthetic ATP production, but not photosynthetic oxygen production. The inability of the organism to grow in the dark with acetate is due to limited oxidative phosphorylation. The primary products of a photosynthetic fixation, using 1,2-C14-acetate, are lipids. β-Hydroxybutyrate polymers are not present in significant quantity. Light assimilation of C14 -bicarbonate gave greatest radioactivity in amino acids and lipids. In the dark, activity from both acetate and bicarbonate was primarily in amino acids. Cell-free extracts incorporated little activity into lipids in the light. Isocitritase activity was found in cells grown in the presence of acetate. Cells grown with bicarbonate, as the carbon source, contained a lower concentration of this enzyme. The organism shows both glyoxalate cycle and Krebs cycle activity. In the light, 2.5-4.7 per cent of the total radioactivity incorporated from acetate and bicarbonate was found in NAD+ when cell suspensions were kept anaerobic. [ABSTRACT FROM AUTHOR]

The article reports on the effect of sodium fluoride and sodium oxalate on the heart ventricles and kidney mesonephra of chick embryos and tests the hypothesis that fluoride inhibits calcium in tissues. The findings are that sodium fluoride is more toxic than sodium oxalate and there is a loss of intercellular cohesiveness.