Extracellular Accumulation of DNA by Hydrocarbon-utilizing Bacteria

Some hydrocarbon-utilizing bacteria grown on n-paraffin as the sole source of carbon accumulated extracellularly a considerable amount of DNA (0.1 g to 0.6 g per liter) which was free from intact cells and slime materials. This was particularly noted when the strains belonging to Pseudomonad were employed. n-Paraffin was a preferable carbon source for the accumulation of DNA by Pseudomonad, while a strain of Arthrobacter accumulated DNA by growing it on glucose.

The DNA thus accumulated was easily isolated and purified free from other cellular components. The purified DNA was highly polymerized (above 4 × l0⁶ daltons), having the same base composition as the cellular DNA.