Originally created 08/28/99

Studies focus on ribosomes

New and more effective antibiotics could be the end result of two studies by scientists who have made progress in deciphering the structure of ribosomes -- complex particles that make the proteins needed for cell functions and structure.

Both studies in the current issue of the scientific journal Nature were based on data generated by a technique called X-ray crystallography, performed at Brookhaven National Laboratory's National Synchroton Light Source.

Scientists hope better understanding of ribosomal structure will lead to the development of more advanced antibiotics to replace those that have lost their effectiveness. New industrial applications are possible as well.

As a result of their success in studying the protein builders, scientists hope someday to produce an antibiotic that would attack the ribosomes in bacterial cells that cause certain diseases.

Researchers from the University of Utah, the Medical Research Council Laboratory of Molecular Biology in Cambridge, England, and Brookhaven Lab in New York worked on the two studies. The scientists include Malcolm Capel, a biophysicist at Brookhaven who was a co-author for both Nature studies; William Clemons Jr., Joanna May, Brian Wimberly and John McCutcheon, all from the University of Utah; Venki Ramakrishnan from the University of Utah and the Medical Research Council; and Nenad Ban, Pul Nissen, Peter Moore and Thomas Steitz, all from Yale University.

"This research is a technical and scientific tour de force," said Dr. Capel. "On a basic science level, these findings represent a giant step on the road to understanding how living organisms make proteins. On a more practical level, many bacterial infections are stopped by antibiotics, which work by inhibiting the production of ribosomes in bacterial cells."

Dr. Capel explained that the successful study of ribosomes using X-ray crystallography could point to progress in the years ahead using the same methodology as a way to seek treatments for various diseases.

"This is the most complex structure ever attempted to be studied or solved by X-ray crystallography," Capel said.

A ribosome reads messenger mRNA (ribonucleic acid), which interacts with transfer RNA and amino acids to build new proteins. It translates the mRNA into chains of amino acids that make up the proteins.

The scientists grew crystals of ribosomes and then froze them to a temperature of minus-173 degrees Celsius in order to prevent radiation damage. An X-ray beam from the Light Source penetrated the crystals, enabling researchers to perform measurements and build a molecular model of the ribosomal structure.