BETTY ANN BOWSER: Australia's Great Barrier Reef has long been famous as a tourist destination, has served as a protective barrier for the Australian coastline, and has been a rich habitat for all sorts of exotic sea life.
But now the coral reefs of the world have become a potential source of chemicals to make lifesaving drugs. Finding those chemicals has only become possible in recent years, with equipment that allowed scientists to spend long periods of time underwater.
LYNDON LLEWELLYN: And that makes it very difficult to work with the team.
BETTY ANN BOWSER: Lyndon Llewellyn thinks there's much to discover.
LYNDON LLEWELLYN: What we're looking for out there is to try and find new chemicals that we haven't even imagined. We can't even think of how we might make these chemicals.
Nature's already made these things. They've been making them for many millions of years. And we want to find them and see if there's any useful applications for them.
BETTY ANN BOWSER: Ironically these discoveries are coming at a time when the coral reefs of the world are in trouble. In just 50 years, nearly half of the coral worldwide has been destroyed by pollution, over-fishing and global warming. And now there is concern over the impact the Asian tsunami has had on reefs in that region. International scientists are still in the field surveying the damage.
Coral reefs are known as the rainforests of the sea, because they support such a wide range of living things. And nowhere on Earth is there a wider range of that biodiversity than on the Great Barrier Reef of Australia.
Many of the creatures living here are not found anywhere else on Earth -- 1,500 species of fish, 4,000 different kinds of shellfish, and 300 varieties of corals. And according to Australian Institute of Marine Science biologist Terry Done, they live in a complex competition with each other.
TERRY DONE: It's plant against plant or it's plant against animal. When you think about it, in a given acre of coral reef, you've got thousands of things trying to occupy this given acre. And the way they do that is through some very novel chemical defenses. The chemistry which goes on, it could be the same source of chemistry and the same sort of compounds which may be helpful for humans in medicine.
BETTY ANN BOWSER: In his lab at the Australian Institute of Marine Science, called AIMS, Walt Dunlap has discovered a chemical that may slow down the process of aging. And he found the raw materials for it on the Great Barrier Reef.
WALTER DUNLAP: We were looking at some marine bacteria, which live in the surface of corals. And there's some very specific bacteria that live in this environment. And so, what we'd like to do is to take what we discovered in the bacteria and to see if we can apply it to human tissues.
And therefore be able to have a much healthier metabolism as we age. And also because there's an antioxidant role to this, it would also have the ability to retard some of the degenerative processes of aging, particularly degenerative disease.
BETTY ANN BOWSER: Dunlap has also discovered another chemical living inside the brightly colored corals that live on the Great Barrier Reef. It produces a sunscreen more effective than anything on today's market.
WALTER DUNLAP: The coral are an animal, but they have a symbiotic algae that lives inside the tissue. And it's really quite interesting. It's the algae that makes the sunscreen, and it donates the sunscreen to the animal because if the animal got sunburned and died, so would the algae. So it's a very close symbiosis, one partner helping the other.
BETTY ANN BOWSER: Even the simplest of marine life is complex, says Chris Battershill, one of Australia's leading marine chemical scientists.
CHRIS BATTERSHILL: The genomes of a lot of these lower marine organisms are large and they have incredible complexity in terms of the type of chemistry that they can create, that they can biosynthesize. And I think there's growing awareness that the answers are there if we just know where to go and look for them.
BETTY ANN BOWSER: A case in point is the solitary sea sponge. It turns out there's more to these creatures than meets the eye. AIMS scientist Alan Duckworth studies the more than 400 species of sponges that live on the Great Barrier Reef.
ALAN DUCKWORTH: Sponges are sea cell marine invertebrates. That means that they cannot swim away or move away in danger. So they've evolved a chemical defense to stop turtles or fish from eating them.
They also use their chemical defense in competition, and also to stop say potential diseases from infecting them. We can use some of those sponge biologically active metabolites to cure our own diseases.
BETTY ANN BOWSER: The hard part is taking these chemicals as they're found in corals and sponges, and turning them into drugs people can use to fight disease. Because the chemicals found on the reefs are so complex, it takes time to transform them into an experimental drug, known as a lead compound. But scientists are getting better at it every day.
CHRIS BATTERSHILL: In the pipeline, as they say, there's actually quite a large number of leads making their way through. I think the reason that we're not seeing any one of these as a success story in terms of pills and bottles on shelves right now, is that the very nature of these chemicals that make them of interest in cancer therapies is also the thing that is the largest stumbling block, and that is that they're very complex molecules; very hard to make.
LYNDON LLEWELLYN: One of the chemicals that is closest to market is a small protein drug that was based upon a toxin found in the venom of cone snails. And one the small proteins found in that toxin has been developed -- well, has been synthesized and is now a drug that is being applied to treating chronic pain. Morphine, in many people who have AIDS and cancer, is unable to be tolerated. They cannot take any more morphine.
So this drug is being developed to be able to treat people. And it's better than morphine. It can replace the morphine for these patients. There's another compound which has been found in a sponge which is being developed as an anti-asthmatic. So it's been used to open up the airways for people who have asthma.
BETTY ANN BOWSER: Do you think there's a cure for certain kinds of cancer out there?
LYNDON LLEWELLYN: Absolutely. There are already a whole range of chemicals being found from marine organisms that have been trialed for anti-cancer treatments.
BETTY ANN BOWSER: Scientists like Llewellyn say they have just scratched the surface. Over the next 10 to 15 years, they think the oceans of the world may hold the answers to medical dilemmas that have stymied scientists for centuries.