Dr. Venkatraman Ramakrishnan

Dr. Thomas A. Steitz

Two of this year's three recipients of the Nobel Prize in Chemistry conducted a substantial part of their award-winning research at the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory.

Dr. Venkatraman Ramakrishnan, a former employee in Brookhaven's biology department and long-time user of the NSLS, now at the Medical Research Council Laboratory of Molecular Biology in Cambridge, UK, and Dr. Thomas A. Steitz of Yale University, also a long-time NSLS user, share the prize with Ada E. Yonath of the Weizmann Institute of Science "for studies of the structure and function of the ribosome."

Ribosomes make the thousands of proteins that are required for the structure and function of each living cell. Specifically, the ribosome translates the genetic instructions encoded by DNA into chains of amino acids that make up proteins. It is composed of two subunits: 30S, which reads the code, and 50S, which links up the amino acids.

Starting in the late 1990s, both Drs. Ramakrishnan and Steitz used a technique called x-ray crystallography at the NSLS to gather atomic-level structures of these two ribosome subunits—Dr. Ramakrishnan on 30S and Dr. Steitz on 50S. In this technique, scientists analyze how a beam of powerful x-rays is scattered by molecules arranged in a crystal to determine the positions of the molecule's individual atoms.

Dr. Ramakrishnan began his work on ribosomes while employed in Brookhaven's biology department from 1983 to 1997, first at the High Flux Beam Reactor and later at the NSLS. Even after leaving the lab to join the University of Utah, he used the NSLS to collect crystallography data that contributed directly to his Nobel Prize. In 1999, his research at NSLS beamlines, especially X25, resulted in the first report of a low-resolution structure of the 30S subunit. In 2000, Dr. Ramakrishnan helped uncover the high-resolution version of the structure, which was based on data from the NSLS, the Advanced Photon Source (APS) at Argonne National Laboratory, and the European Synchrotron Radiation Facility.

At about the same time, Dr. Steitz worked with Brookhaven's biology department to collect NSLS data on the 50S subunit. The first low-resolution structures were solved in 1998 and 1999 using NSLS beamlines X12B and X12C. In 2000, Dr. Steitz' team presented the first high-resolution structure of the 50S subunit using data from NSLS beamlines X12B and X25 and from the APS.

These studies map ribosome functionality at the most basic, atomic level—providing information that is a springboard for researchers to more detailed investigations. The structures of 30S and 50S have been crucial to understanding everything from how the ribosome achieves its amazing precision to how different antibiotics bind to the ribosome, knowledge that could help researchers come to grips with the problem of drug-resistant bacteria.