Oxidation of selected alkanes and related compounds by aPseudomonas strain

The oxidation of octane and decane by a gram-negative bacterium, identified as aPseudomonas species, has been studied. The same rates of growth of the organism were observed in culture media supplemented with alkanes as sole source of carbon, irrespective of whether growth had previously taken place in media containing either octane or glucose. However, only cells previously grown in medium supplemented with octane oxidised this paraffin in the Warburg apparatus. Although 1-octene was not utilised for growth, the rate of oxidation of the olefin by resting cells was the same whether these were previously grown with octoic acid or with octane as sole source of carbon. Small amounts of 1-octanol and 1-octanal were oxidised by resting cells, but at higher concentrations respiration was inhibited.The organism was grown at the expense of radioactive decane (l-C¹⁴) and at least half of the added substrate was oxidised to carbon dioxide. No evidence was found for the accumulation of fatty acids either in the cells or in the culture medium.