Three Share Nobel Prize for Chemistry

Israeli, two Americans explained how the body’s cells create all-important proteins

Vancouver Sun – October 8, 2009 p. B3

Two Americans and an Israeli who used X-ray crystallography to map the precise structure of the ribosome, the cell’s crucial protein-making factory, won the 2009 Nobel Prize for chemistry on Wednesday.

Their independent work, published in 2000, provides fundamental information about the workings of the cellular machinery at the atomic level and is already being exploited by pharmaceutical companies working to make new, more effective antibiotics.

The $1.4-million prize will be shared equally by Thomas A Steitz of Yale University; Venkatraman Ramakrishnan of the MRC Laboratory of molecular Biology in Cambridge, England, who was born in India but is now a U.S. citizen; and Ada E. Yonath of the Weizmann Institute of Science in Rehovot, Israel.

Yonath is the first woman to win the chemistry Nobel since Dorothy Crowfoot Hodgkin of Britain received the 1964 prize, 1 and who was also honoured for her contributions to X-ray crystallography. Yonath is also the first Israeli woman to win a Nobel.

“Its true that a woman hasn’t won since 1964,” she told Israeli radio. “But I don’t know what that means. Does it mean that I’m the best woman since then? I don’t think gender played a role here.”

X-ray crystallography is a time-consuming and tedious science that requires excruciating patience and care to produce crystals of cellular proteins and then sophisticated mathematics to analyse the X-ray patterns that arise when an X-ray beam is focused on such crystals. This is a difficult process with small proteins from cells, and many researchers thought it would be impossible with the ribosome, which is one of the largest proteins in living organisms.

The ribosome translates the cell’s genetic information into the proteins that actually make the cell function.

After 20 years of work, it became apparent that Yonath could finally produce such crystals, and other researchers such as Seitz and Ramakrishnan joined the race to complete the work.

Steitz’s contribution was to determine how the ribosomes oriented within the crystal. That, combined with the information from heavy metals, finally made it possible to determine phase angles and, in 1998, Steitz published the first crude crystal structure of the ribosome’s large subunit.

In 2000, Steitz published the refined structure of the large subunit of the ribosome and Yonath and Ramakrishnan independently published the structure of the small subunits.

Many antibiotics work by blocking the activity of ribosomes in bacteria without affecting those in human cells, but bacteria have grown resistant to most of them. Using the new ribosome images, pharmaceutical companies have been able to determine how the antibiotics actually function and to design new molecules that will circumvent resistance.

Scientists around the world are using the winners’ research to develop new antibiotics that can be used in the ongoing battle against antibiotic-resistant bacteria that cause so much illness, suffering and death,” said Thomas H. Lane, president of the American Chemical Society.

Thomas H. Maugh II Los Angeles Times