New anthrax-fighting drugs are to be developed on home and office PCs, according to Oxford University, Intel, Microsoft and United Devices. The four organisations have combined to create software that can run on millions of PCs around the world, receiving commands and returning results over the Internet. The program, which can be downloaded and run by anyone with a Windows PC, works by using idle time when the computer isn't working on user programs. As most computers spend most time waiting for keystrokes and mouse movements from their users, this can typically be 85 percent of the working day.
The software, described by Oxford University as 'in-silico' testing, has previously been used by United Devices for an ongoing programme of screening molecules for anti-cancer properties, and follows the groundbreaking work of the University of Stanford's Seti@Home project. Seti@Home is by far the world's largest distributed computing system, with three and a half million users contributing a total of 868,000 years processing to date; the United Devices software is currently on around a million PCs.
Molecular testing works by checking billions of potential compounds to see which ones will bind to certain sites on proteins within the anthrax toxin. Such compounds would prevent the lethal factor -- which forms when seven copies of the anthrax toxin form a ring -- from forming, and thus from being able to enter cells. The process of finding the blocking compound has been compared to doing a three-dimensional jigsaw puzzle with random pieces in random orientations, a brute-force approach that is only possible with massive computing power but that lends itself to being split up into millions of simultaneous tests.
Distributed processing like this has been enthusiastically accepted by users, but has led to problems. One system administrator who put the anti-cancer system on many computers under his control at a state college in Georgia, US, was threatened with 30 years in jail for illegal use of the equipment: he agreed out of court to pay a small fine instead. And a small number of users remain cynical -- one commented on a bulletin board that they would be running the anti-cancer system but "it would probably save more lives if they included anti-smoking adverts that popped up from time to time."