Medicine from the Sea

From slime to sponges, scientists are plumbing the ocean's depths for new medications to treat cancer, pain and other ailments

Fred Rainey was standing aboard the 100-foot-long spree about seven miles off the marshy Louisiana coast, rocking on four-foot swells. All around, oil-rig platforms rose like skyscrapers from the heaving waters of the Gulf of Mexico’s “oil patch,” a 64,000-square-mile stretch of shallow ocean where 4,000 steel platforms pump enough petroleum to account for one-third of the nation’s production. But Rainey was not prospecting for oil. Amicrobiologist at Louisiana State University, he was on the trail of an unlikely quarry: slime. In particular, he sought algae, sponges, sea urchins, soft corals and other squishy, mostly immobile organisms that have attached to the oil platforms’ undersides in tangled mats up to a foot and a half thick.

Scientists believe that from such lowly marine creatures a number of medications may one day be derived. Compounds from marine sources are now being tested as treatments for chronic pain, asthma and various malignancies, including breast cancer. (A new generation of industrial chemicals as well— particularly, powerful adhesives—are on the horizon.) Slime, it turns out, is absolutely brilliant at producing useful biochemicals.

Botanists and chemists have long prospected in tropical forests and other terrestrial ecosystems for unusual substances to meet human needs. But the world’s oceans, which may contain as many as two million as yet undiscovered species, have remained largely untapped. Denizens of exotic, difficult-to-reach locations, such as deep-sea hot vents and seabed sediments, have hardly been documented. However, as advances in diving technology open new underwater realms to exploration, and developments in molecular biology and genetics allow labs to isolate molecules at a pace unimagined even a decade ago, the sea’s potential as a biochemical resource is becoming apparent. Over the past 30 years, scientists have extracted at least 20,000 new biochemical substances from marine creatures. Dozens have reached clinical trials; a handful may soon be reviewed by the FDA for possible approval. “Because we humans live on land, that’s where we’ve always looked,” says organic chemist William Fenical, director of the Center for Marine Biotechnology and Biomedicine at the Scripps Institution of Oceanography in La Jolla, California. “But if you were to ask from scratch ‘Where should we explore?’ the answer would always be the sea. Now we’re there.”

Rainey, an easygoing native of Belfast, Northern Ireland, has collected microbes on high-Arctic islands and extremely dry deserts, including the Atacama in northern Chile. An unabashed nondiver, he claims he is unable to identify most marine specimens that aren’t microbes—except perhaps starfish. “If you can see it with the naked eye, I probably can’t help you,” he quips. He made his first foray into marine bioprospecting in 2001, when the Department of the Interior asked Louisiana State University to survey life-forms on oil and natural-gas platforms in the Gulf of Mexico.Marine biologists (and fishermen) have long been aware that offshore oil platforms function as artificial islands, creating new frontiers especially for sessile, or stationary, organisms such as sponges and coral; these organisms typically reproduce by releasing eggs and sperm that, when fertilized, become lar vae. The larvae, in turn, may drift hundreds of miles before attaching to something solid.

Recently, a research team led by Rainey that included specialists in mollusks, algae and foraminifera (tiny one-celled shell-builders) conducted a three-day collecting expedition aboard the spree, a chartered vessel. They embarked from Port Fourchon, Louisiana, a hamlet surrounded by saltwater bayous that are punctuated by giant oil-industry installations and the occasional Cajun fishing shack. The plan was to collect samples at five oil-rig platforms. The researchers and several divers pulled up to the dock with piles of gear and a sixfoot- high freezer for storing specimens. They winched it onto the Spree’s upper deck and lashed it down with industrial- strength straps. The skipper, who insisted on being addressed as Captain Frank, was a large, gruff man with flaming red hair; his feet were bare, his toenails painted purple. He resembled a Viking marauder who had changed into shorts and T-shirt.

We cast off and met in the cabin to talk strategy. At each rig, the divers would chisel off a few pounds of whatever was growing on the platform legs at depths of 60 feet and 30 feet and at the sea-air interface. They would also use large sterile syringes to collect seawater (and thus the microbes inhabiting it). The waters around oil platforms are dangerous environments. Tidal surges and currents can bash a diver’s head against a steel platform. The platform’s legs and crossbraces harbor remnants of commercial fishing nets, not to mention lines fitted with fishhooks. Some platforms are equipped with large intake pipes that draw vast quantities of water; a diver who strays too close could be sucked in and drowned.

Within an hour we were in open water, though on all sides a city of steel oil platforms stretched to the horizon. At some points, I could count 50 at a time. The smallest consisted of just a few girders and pipes, rising 20 or 30 feet out of the water. The largest—gargantuan contraptions fitted with stairways, piping systems, winches, sheds, tanks and satellite dishes—towered 100 feet or higher. Helicopters buzzed from one to another, ferrying crews. Fishing boats bobbed everywhere: the platforms are piscine magnets. Some fish come to hide from predators, others to feed off organisms that have made the platforms home.

The first platform we visited, 42-C, was a rusty yellow monster 16 miles offshore in about 100 feet of murky green water. It sat on three massive legs, its nine well-stems, thick as utility poles, plunging through the center of the platform. Two-foot swells washed up and down its waterline, revealing the topmost layer of what the scientists were seeking: a wrinkled crust of barnacles six inches thick. Acrewman tied the spree to the structure with a heavy rope.Adiver, Sam Salvo, plunged overboard and fastened a bright yellow safety line to one leg about 20 feet down. Rainey had high hopes. “There are so many microbes out here,” he said from the aft deck. “Half of what they bring back will be new to science.”

People have long exploited potent chemicals made by marine creatures. In imperial Rome, historians speculate, Nero’s mother, Agrippina the Younger, paved the way for her son’s reign by lacing hapless relatives’ food with a poison extracted from a shell-less mollusk known as the sea hare. On the Hawaiian island of Maui, native warriors dipped spears in a lethal tidal-pool coral; enemies succumbed if they were so much as nicked.

Scientists have pursued such historical clues with some success. They have isolated a series of powerful toxins from Dolabella auricularia—the sea hare that was most likely the source of the poison that dispatched Nero’s rivals. Today, researchers, including a group at Arizona State University, are investigating the compounds, called dolastatins, for their potential anticancer properties. Chemists have also discovered a perhaps even more toxic compound, palytoxin, from the soft coral Palythoa toxica, likely the organism used to deadly effect by Hawaiian warriors. Researchers at Harvard, Northwestern and Rockefeller universities are trying to determine this compound’s potential.


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