Petroleum microbiology oil while A. borkumensis simutaneously increases synthesis of anionic glucoproteins, which are used to emulsify hydrocarbons in the environment and increase their bioavailability. The presence of crude oil along with appropriate levels of nitrogen and phosphor catalyzes the removal of petroleum either by mechanisms that enhance the efficiency of substrate uptake or by direct biodegradation of aliphatic chains. Two well-known oil spills exemplify large scale marine bioremediation applications: In 1989, the Exxon Valdez ran aground, spilling 41.6 million liters of crude oil, and launching one of the first major bioremediation efforts for an oil spill. Cleanup of Alaskan shorelines relied
Exxon Valdez oil spill effectively a bill of attainder, a regulation that was unfairly directed at Exxon alone. In 2002, the 9th Circuit Court of Appeals ruled against Exxon. As of 2002, OPA had prevented 18 ships from entering Prince William Sound. OPA also set a schedule for the gradual phase in of a double hull design, providing an additional layer between the oil tanks and the ocean. While a double hull would likely not have prevented the "Valdez" disaster, a Coast Guard study estimated that it would have cut the amount of oil spilled by 60 percent. The "Exxon Valdez" supertanker was towed