By Maggie Fox

WASHINGTON: Scientists using the power of more than a million home computers, all linked together and cranking along as one, have come up with thousands of possible compounds that could be developed as a cure for anthrax, officials said on Friday.

The British researchers who helped organize the project, which they said they completed with unprecedented speed, handed over two compact disks containing 300,000 potential drugs to U.S. and British government officials.

Of these, they said 12,000 looked like good candidates for a cure for anthrax infection -- not an antibiotic, but an antitoxin to counter the lethal effects of the bacteria.

"This has enabled us to have an enormous amount of power," Graham Richards, a chemistry professor at Britain's Oxford University who helped organize the project, told a news conference.

"In only 24 days we could test 3.5 billion molecules," said Richards, adding that he believed this would be more than any pharmaceutical company could do on its own. Using traditional methods, he said, the project would have taken years.

"This is an historic first use of the Internet as a computing platform to solve a critical, real-world problem with a scope and a speed that simply could not be achieved using traditional computing methods," Ed Hubbard, Chief Executive Officer of United Devices, a Texas-based company that helped in the effort, told the news conference.

Anthrax can easily be treated using antibiotics, but only if people start taking the drugs before symptoms progress too far. That is no good if the patient does not know he or she has been exposed -- as was the case with thousands of U.S. postal workers who handled anthrax-laced letters last October.

Two postal workers were among the five people who died in those attacks last year. All were treated with antibiotics, but it was too late. Anthrax bacteria make a toxin that causes a deadly overreaction by the immune system, and while antibiotics kill the bacteria, they do nothing to the toxin already in the body.

Work has been underway to find an antitoxin, an effort that has accelerated since the October attacks. Late last year, scientists found a potential target -- a place that could be blocked on the anthrax bacteria that should stop the effects of the toxin.

Knowing the shape of this target, scientists can look for molecules that will fit into it, like a lock and key, and block it. But screening the billions of known compounds takes a huge amount of computing power.

The National Foundation for Cancer Research, a U.S. group that funds cancer research, has had a project going since April in collaboration with Oxford, United Devices and Intel Corp. to screen potential treatments for leukemia.

Like the SETI@home project, which uses home computer downtime to process radio emissions in a search for extraterrestrial life, it uses computer time donated by personal computer users.

When a person downloads the screensaver, found at http://www.chem.ox.ac.uk/anthrax/, the first thing it does is dial the Austin server and ask what this particular personal computer can do. It gets its assignment and crunches numbers when the computer is not in use.

The NFCR has 1.5 million computer users in 215 countries, including two in the Vatican. They will eventually screen 26 compounds for possible leukemia cures. The companies, along with Microsoft, adapted the cancer software to work for anthrax. The anthrax project, started on Jan. 22, was finished by Feb. 14.

The list of 300,000 drug candidates goes to the U.S. Department of Defense and Britain's Office of Science and Technology, Ministry of Defense and Department of Health. Dr. Anna Johnson-Winnegar, deputy assistant defense secretary for chemical and biological defense, said the list would be shared with the Health and Human Services Department, which oversees the National Institutes of Health.

Both the defense department and the NIH have labs that can test screened compounds against anthrax. It usually takes, on average, 10 years to bring an experimental new drug to market, but Richards said he believed any product to emerge from this search could be used more quickly -- perhaps within two to four years.

"This would be somewhat different," Richards said. "This is more likely to initiate something you would provide to protect troops, or postal workers even, who are suspected of being attacked."

(C) Reuters Ltd.