The Regulation of Peroxisomal Enzyme Systems of Tetrahymena pyriformis by Fatty Acid Composition, Glucose and Oxygen in the Medium

• Published in: Journal of biochemistry (Tokyo) Vol. 97; no. 6; pp. 1631 - 1636
• Main Authors: TAKEI, Mineo, GOTOH, Ken-ichi, WATANABE, Takafumi, SUGA, Tetsuya
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01.06.1985
• Subjects: Acyl-CoA Dehydrogenases - metabolism; Acyl-CoA Oxidase; Animals; Biological and medical sciences; Cell metabolism, cell oxidation; Cell physiology; Centrifugation, Density Gradient; Culture Media; Fatty Acids - pharmacology; Fundamental and applied biological sciences. Psychology; Glucose - pharmacology; Microbodies - drug effects; Microbodies - enzymology; Molecular and cellular biology; Oxidoreductases - metabolism; Oxygen - pharmacology; Palmitates - pharmacology; Substrate Specificity; Tetrahymena pyriformis; Tetrahymena pyriformis - drug effects; Tetrahymena pyriformis - enzymology; Tetrahymena pyriformis - growth & development; Culture medium; Protozoa; Oxygen; Regulation(control); Enzyme; Tetrahymena pyriformis; Peroxisome; Oxidation; Glucose; Fatty acids; Glyoxylate cycle
• ISSN: 0021-924X; 1756-2651
• DOI: 10.1093/oxfordjournals.jbchem.a135220

The effect of the chain length of fatty acids on peroxisomal enzyme activities of Tetrahymena pyriformis was investigated. The growth of cells and the activities of peroxisomal enzymes were inhibited markedly by the addition of medium-chain fatty acids (C6–C12) to the culture medium, whereas the addition of longer-chain fatty acids (C14–C18) resulted in a slight increase of growth and in the marked stimulation of enzyme activities concerned with fatty acid β-oxidation and the glyoxylate cycle in peroxisomes. Peroxisomal β-oxidation (fatty acyl-CoA oxidase) was more potent towards longer-chain fatty acids than the mitochondrial activity (fatty acyl-CoA dehydrogenase). The induction of the peroxisomal β-oxidation system by palmitate was repressed both by the addition of glucose and the aeration of the culture medium, whereas that of the peroxisomal glyoxylate cycle was repressed only by the addition of glucose to the medium. These results indicate that peroxisomal enzyme systems related to the β-oxidation of fatty acids and the glyoxylate cycle are regulated by the compositions of fatty acids, glucose, and oxygen in the medium.