Acinetobacter HO1-N grown on hexadecane as a sole source of carbon and energy was demonstrated to cytoplasmically sequester this hydrocarbon. Cultures grown with hexadecane and heptadecane accumulated intracytoplasmically both hydrocarbons. The accumulation of specific alkanes was non-specific while the oxidation of the pooled hydrocarbon was highly specific. Naphthalene was highly inhibitory to the growth of this microorganism but slowly co-oxidized in the presence of hexadecane.