3 Win Nobel Prize for Work Mapping Cells' Key Machinery

STOCKHOLM, Oct. 7 -- Two Americans and an Israeli won a Nobel Prize in chemistry Wednesday for creating detailed blueprints of the protein-making machinery within cells, research that is being used to develop new antibiotics.

Venkatraman Ramakrishnan, Thomas Steitz and Ada Yonath will split the $1.4 million award for their atom-by-atom description of ribosomes.

Yonath, 70, is the fourth woman to win the Nobel chemistry prize and the first since 1964.

Ribosomes are key to life. They use instructions from genes to make thousands of proteins that control what happens in the body. Many antibiotics kill bacteria by attacking their ribosomes, and the detailed descriptions by the new Nobel winners are being used to develop drugs.

The three scientists worked independently and published their results virtually simultaneously in 2000.

"I didn't feel it was a personal competition, but it was a bit of a race," said Steitz, 69, a professor at Yale University. "We were all taking separate approaches."

Yonath works at the Weizmann Institute of Science in Rehovot, Israel. Ramakrishnan, 57, is at the MRC Laboratory of Molecular Biology in Cambridge, England, where he went after working in the United States. Steitz is a professor of molecular biophysics and biochemistry at Yale and is an investigator with the Howard Hughes Medical Institute.

The academy called Yonath a "strong-willed pioneer" for starting on the quest in the 1970s, when most people thought it would be impossible. She, and eventually her co-winners, used a technique called X-ray crystallography to try to pinpoint the positions of individual atoms in the ribosome. Basically, that technique involves showering the ribosome with X-rays and determining how the rays scatter.

Ramakrishnan described his work on ribosomes as an attempt to understand "this large molecular machine that takes information from genes and uses it to stitch together protein."