BIOTIN AND THE METABOLISM OF BAKER'S YEAST

摘要: Based on experimental results and the presented in literature a model for metabolism of baker's yeast under biotin deficiency is presented. In these conditions most sensitive point carboxylation pyruvate to oxaloacetate catalyzed by biotin-containing carboxylase. Because rate glycolysis not affected biotin-deficiency accumulates cells partially excreted into medium. The high pool means that mainly fermentative even vigorously aerated cultures. oxidation acetyl-CoA proceeds almost unaffected, as can be seen production elevated amounts ethyl acetate grown sub-optimal concentrations. Acetyl-CoA carboxylase, which also has prosthetic group, this growth factor without fatty acids lipids are same or higher than optimal conditions. from towards TCA cycle glutamate strongly aspartate, present strictly limited amounts. This causes an over-production metabolic intermediates, e.g. diazotizable arylamine hypoxanthine well citrulline. Their conversion normal cell constituents, purine nucleotides arginine, dependent aspartate available thus depressed lack biotin.