Prospecting Beneath the Seas
For decades, scientists have searched for plants that contain disease-fighting compounds. Some powerful cancer drugs are derived from a flower that grows in the forests of Madagascar. But experts say a better place to search for these natural medicines may be among the myriad life forms that dwell in the ocean. As NPR's Eric Niiler reports, researchers are now scouring the seven seas in hopes of finding the next blockbuster drug.
Marine scientist William Fenical doesn't actually look for new creatures in the ocean. He looks below it -- in the mud on the seafloor. Thousands of feet beneath the water's surface, he's discovered a new group of mud-loving bacteria with some amazing properties: the ability to produce a powerful human antibiotic.
"What's different here is that we're looking at a resource in the ocean that no one conceived would have any value in medicine, or any value at all," said Fenical, a professor of marine chemistry at the Scripps Institution of Oceanography.
Fenical and colleagues collected samples of seafloor mud from the Red Sea, the Caribbean and Mexico's Sea of Cortez. Back at the lab, the researchers processed the sediments, sorting for antibiotic-producing microbes. Their results, published in October 2002 and January 2003 in two scientific journals, were startling.
"Somewhere around 35 percent of the strains we tested contain new molecules that are antibiotic, potential fungal inhibitors and also inhibitors of fungal cell growth," Fenical said.
Fenical's findings are just the latest development in the field of marine bio-prospecting, a sort of underwater treasure hunt for medicinal and commercial compounds. San Diego-based biotech firm Diversa is working with microbes harvested from whale bones and carcasses -- which are rich in oils and lipids -- found in the deep, cold waters off California and Hawaii.
Diversa scientists have used the whale bacteria to make a laundry detergent that works in cold water. The same mechanism the microbes use to digest whale fat can also break down greasy stains. And that's not all that undersea bacteria can do.
"These enzymes can be applied to things like novel pharmaceuticals, food, cosmetics, pulp and paper treatment," said Jay Short, president and CEO of Diversa.
Researchers are also searching for new drugs amid the animals stuck to coral reefs in the tropics. Because they can't swim away from predators, these animals rely on other tricks to prevent being eaten, including poisons that affect the hearts or nervous systems of their enemies. According to Elliott Norse, president of the Marine Conservation Biology Institute in Redmond, Wash., that kind of poison might also work against human cancer cells.
One promising drug, bryostatin -- an anti-cancer agent made from a moss-like animal called a bryozoan -- is now undergoing clinical trials for use in humans. Other drugs are being made from toxins found in corals, sponges and shell animals. Each year, the National Cancer Institute (NCI) screens tens of thousands of plant and animal samples for medicinal properties.
But Gordon Cragg, director of NCI's Natural Products Branch, warns it can take many years to develop drugs from the sea. Since the Institute's screening began in 1960, it has produced only two approved drugs.
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