Alcohol dehydrogenase activity and electron transport in living yeast.
1. The excretion of H(+) ions, with practically equivalent uptake of K(+) ions (from 0.1m-potassium chloride), occurs during the aerobic oxidation of ethanol. 2. Acetaldehyde and acetic acid formed at the same time are quantitatively equal to the amount of ethanol oxidized. 3. A slow uptake of K(+) ions occurs during the oxidation of acetaldehyde and a more rapid uptake during the oxidation of d-glyceraldehyde 3-phosphate. 4. The anaerobic reduction of methylene blue is studied, and the inhibitory effect of K(+) and other inorganic cations on the system demonstrated. 5. The cation requirement for equal inhibitory effect is parallel with the reciprocals of the transport affinities for the ;physiological K-carrier' (as taken from Conway & Duggan, 1958). 6. The cation inhibition of methylene blue reduction is reversed by treatment of the yeast with Teepol or by freezing-and-thawing. 7. Azide is shown to inhibit the reduction of methylene blue with intact cells. The inhibition is partially reversed by Teepol treatment and completely by freezing-and-thawing.
D000429:Alcohol Oxidoreductases / Q000378:metabolism*; D001386:Azides / Q000494:pharmacology; D004579:Electron Transport; D000431:Ethanol / Q000378:metabolism; D006859:Hydrogen / Q000378:metabolism; D008751:Methylene Blue; D010084:Oxidation-Reduction; D010101:Oxygen Consumption; D010619:Phenazines / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism; D012440:Saccharomyces / Q000378:metabolism*
D001386:Azides; D010619:Phenazines; D000431:Ethanol; D006859:Hydrogen; D000429:Alcohol Oxidoreductases; D011188:Potassium; D008751:Methylene Blue