PROTEIN STRUCTURE:
NMR Maps Giant Molecules As They Fold and Flutter
Michael Balter
OXFORD, UNITED KINGDOM--How do polypeptides--linear chains of up to 300 or more amino acids--arrive at the intricately folded, three-dimensional conformations characteristic of biologically active proteins? Powerful analytical techniques such as nuclear magnetic resonance (NMR) spectroscopy have begun to unravel the paradox by giving structural biologists a glimpse into the dynamics of proteins. At a meeting here on the biological uses of NMR, researchers presented some of the fruits of new NMR techniques that are providing much higher levels of resolution (see "Lining Up Proteins for NMR"). Using these new methods, researchers are opening a window on the intricate steps in the folding process and learning that proteins may be much more flexible and dynamic than previously thought--a finding that could have profound implications for how these macromolecules carry out their functions.