|MadSci Network: Microbiology|
One reason you may be having trouble finding it, is that there is no one answer. Let us look at the problem from a historical context. The original strain that was constructed in the late '70s to early '80s which was sometimes called a superbug was a strain of Pseudomonas, in fact it was Pseudomonas putida. Those researchers transferred a series of plasmids from different natural isolates into one strain so that it had the capacity to degrade long chain hydrocarbons, the stuff of oil. Although it was great publicity, this strain didn't really prove all that useful. It worked fine in the lab, but not in the wild. Since that time people have identified many different bacteria that can degrade components of oil. Certainly many Pseudomonads can, as well as species of Rhodococcus and a variety of other strains as well. However these days they usually don't employ any one single strain, but rather rely on what is called a consortium, or a mixture of different bacteria. Each bacteria is best suited for degrading one or a few things, but in combination they work most effectively to clean up an oil spill. Often times commercial firms sell these bacterial mixtures which they isolated from the wild, and don't always even know all the different bacteria that is in the mixture. Therefore, there is no single bacterial species that we can say is the one that eats oil. There are many that can do it, but combinations of them are what work best.
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