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From a watery grave - Bacteria that feast on whale bones reveal the secret of cool washes

点击量:   时间:2018-02-09 08:02:12

By Andy Coghlan WHALE corpses rotting deep in the Pacific Ocean are yielding bacterial enzymes that could let us wash our dirty laundry in cold water. Samples from whale carcasses have been shown to contain enzymes that readily digest oils and fats between 15 °C and 20 °C. “That’s ideal for cold-water detergents,” says Jeff Stein, principal scientist at Diversa, a biotechnology company in San Diego, California. Diversa is collaborating with oceanographer Craig Smith and his colleagues at the University of Hawaii at Manoa. Smith studies the creatures that live on whale corpses using a submersible called Alvin, owned by the US Navy and operated by the Woods Hole Oceanographic Institution in Massachusetts. Smith knows of five whale corpses off the coast of southern California. One, which he discovered by chance in 1987 and nicknamed the Grateful Dead Whale, is the oldest and has been rotting for at least 15 years. Another was discovered by the US Navy while searching for a stray torpedo. The other three are beached whales that Smith sank to help his research. The corpses teem with unusual bacteria, crabs and worms. After the flesh has been eaten away, which takes a few months, slimy mats of bacteria coat the bones. “The bacteria subsist on the oils that ooze out of these bones,” says Stein. The fat-digesting enzymes in conventional biological washing powders work efficiently only at temperatures higher than 40 °C. Because the seabed is so cold—around 5 °C—the bacteria that colonise whale corpses have evolved unusual enzymes to digest the oils. These enzymes become more active if warmed slightly, and Diversa’s tests suggest that they could be used for washing clothes at 15 °C. So far, Smith has handed Diversa bones and tissue from three whales, and more expeditions are planned thanks to a $300 000 grant awarded to Smith’s team last month by the US National Science Foundation. Diversa’s scientists are now tinkering with the enzymes to make them even more potent against fats such as palmitic acid, which is found in butter and margarine and is responsible for some of the most stubborn stains on clothes. Smith says he never expected his academic work on whale decomposition to yield any commerical spinoffs. “It’s a good example of how, in basic science, you don’t know where the applications will come,