* Karplus, Levitt and Warshel pioneers in computer analysis
* Work has accelerated progress in medicine and industry
* Computational chemistry now used at all pharma companies
By Mia Shanley and Sven Nordenstam
STOCKHOLM, Oct 9 (Reuters) - Three U.S. scientists won theNobel chemistry prize on Wednesday for pioneering work oncomputer programs that simulate complex chemical processes andhave revolutionised research in areas from drugs to solarenergy.
The Royal Swedish Academy of Sciences, awarding the prize of8 million crowns ($1.25 million) to Martin Karplus, MichaelLevitt and Arieh Warshel, said their work had effectively takenchemistry into cyberspace. Long gone were the days of modellingreactions using plastic balls and sticks.
"Today the computer is just as important a tool for chemists as the test tube," the academy said in a statement."Computer models mirroring real life have become crucial formost advances made in chemistry today."
Chemical reactions occur at lightning speed as electronsjump between atomic nuclei, making it virtually impossible tomap every separate step in chemical processes involving largemolecules like proteins.
Powerful computer models, first developed by the threescientists in the 1970s, offer a new window onto such reactionsand have become a mainstay for researchers in thousands ofacademic and industrial laboratories around the world.
'LIKE A MOVIE'
In drug design, for example, scientists can now usecomputers to calculate how an experimental medicine will reactwith a particular target protein in the body by working out theinterplay of atoms.
"The field of computational modelling has revolutionised howwe design new medicines by allowing us to accurately predict thebehaviour of proteins," said Dominic Tildesley, president-electof Britain's Royal Society of Chemistry.
Today, all pharmaceutical companies use computationalchemistry to screen experimental compounds for potential asmedicines before further testing them on animals or people.
The ability to model chemical reactions has also grown ascomputers have become more powerful, while progress inbiotechnology has produced ever more complex large molecules foruse in treating diseases like cancer and rheumatoid arthritis.
"It has revolutionised chemistry," Kersti Hermansson,professor in organic chemistry at Uppsala University, said ofthe computer modelling. "When you solve equations on thecomputer, you obtain information that is at such detail it isalmost impossible to get it from any other method."
"You can really follow like a movie, in time and in space.This is fantastic detail..."
Karplus, a U.S. and Austrian citizen, carries out researchat the University of Strasbourg and Harvard University. Levitt,a U.S. and British citizen, is at the Stanford University Schoolof Medicine. Warshel, a U.S. and Israeli citizen, is a professorat the University of Southern California, Los Angeles.
The approach has applications in industrial processes, suchas materials science, the design of solar cells or catalystsused in cars. For the former, programs can be used to mimic theprocess of photosynthesis by which green leaves absorb sunlightand produce oxygen.
It was not an easy scientific journey, however. Warshel saidhe had been convinced of the case for using computers tosimulate chemical reactions since 1975 but did not know if hewould live to see it adopted.
"I always knew it was the right direction, but I hadinfinite difficulties and setbacks in the research. None of mypapers were ever published without being rejected first," hetold Reuters.
Karplus said his early work using computers was initiallymet coldly by many of his scientific colleagues in the '70s.
"My chemistry colleagues thought it was a waste of time," hetold reporters at Harvard in Cambridge, Massachusetts, addingthat the next generation of scientists should be courageous and"not believe their colleagues necessarily if they say they can'tdo something."
Karplus's family brought him to the United States in 1938after the Nazi annexation of Austria. Austrian President HeinzFischer said on Wednesday the Nobel Committee's decision toaward the prize to Karplus "is gratifying and at the same timean occasion to reflect on Austria's responsibility."
A unique insight of the trio's work was to use computersimulations to combine quantum mechanics, which explains themaking and breaking of chemical bonds, with classical Newtonianmechanics, which captures the movement of proteins.
Ultimately, the ability to computerise such complex chemicalprocesses might make it possible to simulate a complete livingorganism at the molecular level - something Levitt has describedas one of his dreams.
"I am a computer geek," Levitt told Reuters.
Back in the 1960s there were no personal computers, he said,so the only way for scientists to get their hands on a computerwas to find ways to use it in their work.
"That's not to say that I became a computational chemist inorder to play with computers, but a large part of any creativeactivity is to feel that you're playing."
"I think if everybody did everything with passion, the worldwould be a better place," he said.
Chemistry was the third of this year's Nobel prizes. Theprizes for achievements in science, literature and peace werefirst awarded in 1901 in accordance with the will of businessmanand dynamite inventor Alfred Nobel.
- Martin Karplus
- Computational chemistry
- Chemical reactions
- Nobel chemistry prize