Mineralization of [14C]octadecane by Acinetobacter calcoaceticus S19

Uptake of octadecane by Acinetobacter calcoaceticus S19 was found to be 70% during growth (doubling time of 4 h), of which 60% was incorporated into the cells and 40% was oxidized to (CO2)-C-14. The ratio of [C-14]octadecane uptake to its mineralization by whole cells was similar to that found during the growth of A. calcoaceticus S19. After 4 h of incubation of cells with [C-14]octadecane, 44% was mineralized to (CO2)-C-14, while the rest remained associated with the cells. Octadecane uptake was not observed under anaerobic conditions, indicating an absolute requirement for oxygen. Acinetobacter calcoaceticus S19 converted octadecane to the corresponding octadecanol and octadecanoic acid; the corresponding aldehyde was not detected, however. Octadecanoic acid was partially degraded through beta-oxidation to CO2 and partly assimilated as cell biomass.