Drugs from the sea may help medical experts

International scientists have successfully cloned marine DNA in a breakthrough they say will provide promising "drugs from the sea" to treat cancer and viral diseases.

The team, working at the Australian Institute of Marine Science (AIMS), said on Friday that the cloning of DNA from marine organisms like sponges and sea squirts into E.coli bacteria could provide a sustainable supply of marine-derived pharmaceuticals.

AIMS called the breakthrough a "world-first achievement" that would eliminate supply obstacles that have stalled the development of many promising drugs.

Walt Dunlap, a leading biochemist at AIMS, said compounds from sea squirts, sponges and other marine organisms showed "exceptional promise for the treatment of cancer, inflammation and viral diseases".

"The main problem has been obtaining a large-scale supply of these complex chemicals for worldwide use in an ecologically sustainable and economically viable way," Dunlap said in a statement.

The new methodology, developed by an international team of scientists from AIMS, the University of Aberdeen and the London School of Pharmacy, has removed "a huge hurdle to the development of new drugs from the sea," he said.

"Using gene technology we need not return to the sea again to obtain the drug for worldwide use."

The lead AIMS scientist on the project, Chris Battershill, called his group's success "one of the most important breakthroughs in marine biotechnology in recent times".

Despite their potential in curing disease, few marine-derived drugs reach the market because of the considerable cost of developing a guaranteed supply for clinical use.

"Without an assured source pharmaceutical companies are unwilling to invest the estimated $800-million it takes to get a drug from the sea to the shelves," Battershill said.

"To produce a cancer-fighting drug from a marine-source, for example, we might need to harvest 20 000 tons of a particular sponge per year to meet the global market need and this is ecologically unsound," he said.

The AIMS team solved the problem by taking the genes responsible for manufacturing a cancer-fighting chemical produced by a sea squirt and placing them in E.coli - an easy-to-culture bacterium - that then produced the chemical.

"Using this methodology, we need only one small collection of the sea squirt to obtain a long-term supply of the chemical, which has potential for the treatment of certain types of lymphoma," said Paul Long, a team member from the London School of Pharmacy.

Details of the research were published in the July edition of the international journal ChemBioChem.

Source: www.iol.co.za