ALL-OIL DIET

How does the metabolism of oil-eating bacteria break down oil? And how do they survive when no oil is available?

The most closely studied of these rod-shaped bacteria, Alcanivorax borkumensis, was first identified in 1998 near the Isle of Borkum in the North Sea. It has several efficient enzymes that break down a variety of the components of crude oil called alkanes.

The process transforms these large hydrocarbon molecules into smaller components, producing energy and carbon. The bacteria can also use some other organic compounds found in oil. Certain strains of the organism were found to produce a previously unknown class of glucose lipids that reduce the surface tension of water, and most of their degradation action takes place where oil meets water.

The bacteria are widespread and are found in barely detectable concentrations wherever even a thin film of oil is present in the ocean, a common phenomenon resulting from natural oil deposits as well as oil spills.

When there is a large supply of oil, Alcanivorax borkumensis quickly become the dominant microorganism and thrive on the contamination. The species is said to have a competitive advantage over other bacteria because its multiplicity of enzymes lets it use so many of the components of crude oil.