There are natural, genetically modified and otherwise enhanced species of bacteria that thrive on certain components of oil and under certain conditions. When the aromatics in oil, such as benzine have vented off, the excessive amounts of oil are removed and when the oil is spread out enough to allow for high enough oxygen levels, certain species of fungi, bacteria and even some higher species of living things actually metabolize the hydrocarbons in oil for energy and nutrition. There must also be temperature and pH levels within certain ranges.
Pseudomonas, flavobacterium, arthrobacter, and azotobacter are common bacterial types that “eat” oil. These bacteria occur naturally at an estimated 0.1 percent of the bacterial population.
Zooglea, Alkaligenes, Frateuria, Putida, and Aeruginosa are five of the pseudomonas family that have been discussed in oil eating bioremediation.
A specific bacteria, oleophilic bacteria or Oil Eating Bacteria (OEM) is introduced to supplement the naturally occuring species that help to consume oil after a spill.
In 1981 Mohan Chakrabarty patented the first version of a genetically engineered oil eating bacteria. This led to the landmark Supreme Court decision that allowed the patenting of life forms. Mr Chakrabarty removed plasmids from the four species of pseudomonas oil eating bacteria, combined them, then exposed it all to ultravioliet light to create the single, more stable species.
Of the psuedomonas family, there are said to be four species that went into Mr Chakrabarty’s recipe. It is said that the genetically engineered OEM were a meld of the four original species, but it is very difficult to identify all of the possibilities. The four species were found to compete with each other, decimating the population, so a hybrid was created to reduce the competition. This modified and more stable species was patented in 1971 and has been in use since then.
The controversy is in two areas: the “side effects” of the pseudomonas activity include a lot of slime and jelly and the possibility of this potentially harmful bacteria becoming a mutated health problem of enormous proportions.
In summary, the work of identifying and modifying oil eating life forms and of improving their oily environments will continue to be an issue as the current British Petroleum oil spill and past oil spills continue to create needs for bioremediation after the excessive amounts of oil are removed. But, as with all modified life forms, these life forms have the potential to create much controversy and fear of them going out of control.
CR-4, “Oil Eating Bacteria Thread”, February 2009
Christina Agapakis, “Oil Eating Bacteria”, June 2010
Sarah Castor-Perry, “This Week In Science History, The First Genetic Patent”
P.U.M. Rhavigan and M. Vivekanandan, “Bioremediation of oil spill sites through seeding of naturally adapted Pseudomonas putida”
E. Harder, “The effects of essential elements on bioremediation”, Little Flower Academy