Researchers in Illinois have created what is believed to be the first atomic-level computer-based simulation of a complete functioning organism.

According to the scientists, the breakthrough has the potential to speed development of new drugs to combat viruses in plants, animals and, ultimately, people.

A research team led by Professor Klaus Schulten at the University of Illinois at Urbana-Champaign simulated a plant virus with as many as one million moving atoms.

The achievement is described by the team as historic due to the sheer complexity of the problem. Had the researchers relied on today's desktop computer systems, they would not have finished until 2041.

Professor Schulten's team used part of an SGI Altix 3700 Bx2 system located at the National Center for Supercomputing Applications. The Altix system allowed them to calculate how all the atoms interact every femtosecond, or one-millionth-of-a-billionth of a second.

Although the virus is so small that biologists refer to it as a particle, the ability to simulate the organism as it functions holds tremendous promise for medical research.

"It allows us to see how the virus assembles and disassembles," said Peter Freddolino, a member of the Illinois research team which also includes physicist Anton Arkhipov.

"Because assembly and disassembly are two of the key steps in the viral life cycle, understanding these events could lead to the development of drugs designed to attack them at these vulnerable points."