ISSN:
1573-6776
Keywords:
Alcohol dehydrogenase
;
aldehyde dismutase
;
enzyme kinetics
;
Saccharomyces cerevisiae
;
yeast
Source:
Springer Online Journal Archives 1860-2000
Topics:
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Abstract Yeast alcohol dehydrogenase (EC 1.1.1.1) is able to catalyze the oxidation of acetaldehyde by NAD+ with a concomitant formation of ethanol, at pH 8.8 and pH 7.1; the stoichiometry of aldehyde oxidation vs. ethanol formation is 2:1. This enzymatic reaction obeys the Michaelis-Menten kinetics and was characterized by a high KM for acetaldehyde (68 mM) and a low kcat (2.3 s−1), at pH 8.8, 22 °C. There is no visible burst of NADH during the reaction, from pH 7.1–10.1. Therefore, we have concluded that the enzyme catalyzes an apparent dismutation of two molecules of acetaldehyde into a molecule of acetic acid and a molecule of ethanol.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1005476115349
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