Utilization of Primary and Secondary Alcohols by the Detergent-degrading Bacterium Pseudomonas C12B

Abstract

SUMMARY: The capacity of the detergent-degrading bacterium Pseudomonas C12B to grow on, and oxidize, a range of primary and secondary alcohols of chain lengths from C2 to C16 was examined. The organism was able to grow on most primary alcohols tested, and especially well on the C10–C12 homologues. Of several secondary alcohols, C11–C13 homologues of alkan-2-ols supported good growth, as did some long-chain symmetrical or near symmetrical alcohols. There was constitutive synthesis of primary and alkan-2-ol dehydrogenase activities, enabling the organism to oxidize primary alcohols and alkan-2-ols up to at least C11. Experiments with resolved d- and l-octan-2-ols suggested that the constitutive alkan-2-ol dehydrogenase activity was specific for d-isomers. Growth on secondary alcohols induced synthesis of l-alkan-2-ol dehydrogenase(s) and also greatly increased the capacity of extracts to oxidize racemic alkan-2-ols in the range C6–C11. An enzyme with high activity towards symmetrical alcohols was also induced by growth on secondary (especially symmetrical) alcohols. Collectively, the various alcohol dehydrogenase activities detected would enable Pseudomonas C12B to oxidize all the alcohols liberated from mixed alkyl sulphate detergents by the organism's complement of two primary and three secondary alkylsulphatases.