Retroenantiomers— a close match indeed

Abstract

Researchers at Rockefeller University, New York City, have obtained direct evidence of the expected similarity between the surfaces of a complex cyclic peptide and its retroenantiomer. And they have shown that even very short peptides can be designed to form stable (Β-hairpin structures. Associate professor David Cowburn and postdoctoral fellows James M. McDonnell, David Fushman, and Sean M. Cahill at the Laboratory of Physical Biochemistry used nuclear magnetic resonance (NMR) spectroscopy to derive the solution structures of the cyclic peptide cyclo(L-262) and its retroenantiomer cyclo(n>262). The work, done in collaboration with Brian J. Sutton, a reader in molecular biophysics at Randall Institute, King's College, London, shows the two peptides have very similar topologies [ J. Am. Chem. Soc., 119, 5321 (1997)]. Cyclo(L-262) contains only naturally occurring L-amino acids and can be degraded by proteases. Substituting D-amino acids would result in a protease-resistant peptide, but it won't fit the tar...