Induction of NAD+ dependent alcohol dehydrogenases with activity towards long chain aliphatic alcohols in mesophilic, thermophilic and extreme thermophilic microorganisms

The production of alcohol dehydrogenases with the capacity of oxidizing long chain aliphatic alcohols by mesophilic, thermophilic and hyperthermophilic strains induced by aliphatic alcohols and alkanes with 2-24 carbon atoms has been studied. Seven strains were tested: the mesophilic yeast Candida tropicalis ATCC20336, the thermophilic bacterium Thermus AB1and five hyperthermophilic bacterial strains: Thermus thermophilus HB27, HNI11, NR17, PRQ16 and PRQ25. Only C. tropicalis ATCC20336, Thermus AB1 and T. thermophilus PRQ25 produced alcohol dehydrogenases with the capacity of oxidizing aliphatic alcohols with 22 and 24 carbon atoms, after induction with 1-hexacosanol, 1-docosanol and 1-eicosanol, respectively. Higher initial reaction rates of oxidation of docosanol and eicosanol were obtained with the enzyme from C. tropicalis ATCC20336, with values of 196.9 and 218.8 μmol NADH min−1 g of protein−1, respectively.