Thermostable type III alcohol dehydrogenase. For oxidation activity, the best substrates are 1-butanol and 1-hexanol, followed by ethanol. Shows lower activity with ethylene glycol, isopentanol, isopropanol and glycerol. Displays higher reduction activity in the presence of butanal, followed by acetaldehyde. Has lower activity with hexanal and acetone. a primary alcohol + NAD(+) = an aldehyde + H(+) + NADH butan-1-ol + NAD(+) = butanal + H(+) + NADH hexan-1-ol + NAD(+) = H(+) + hexanal + NADH ethanol + NAD(+) = acetaldehyde + H(+) + NADH Dependent on a divalent cation for ethanol oxidation, among which Mn(2+) is optimal. Compared with the oxidation reaction, displays about 30% acetaldehyde reduction in the absence of divalent cation. Shows maximal reduction activity in the presence of Fe(2+). kcat is 0.27 sec(-1) for ethanol oxidation. kcat is 69 sec(-1) for acetaldehyde reduction. Optimum pH is 8.5 for oxidation and 7.0 for reduction. Optimum temperature is 75 degrees Celsius for both ethanol oxidation and acetaldehyde reduction. Belongs to the iron-containing alcohol dehydrogenase family.