Solution structure of the immunodominant region of protein G of bovine respiratory syncytial virus.

The three-dimensional solution structure of the immunodominant central conserved region of the attachment protein G (BRSV-G) of bovine respiratory syncytial virus has been determined by nuclear magnetic resonance (NMR) spectroscopy. In the 32-residue peptide studied, 19 residues form a small rigid core composed of two short helices, connected by a type I' turn, and linked by two disulfide bridges. This unique fold is among the smallest stable tertiary structures known and could therefore serve as an ideal building block for the design of de novo proteins and as a test case for modeling studies. A characteristic hydrophobic pocket, lined by conserved residues, lies at the surface of the peptide and may play a role in receptor binding. This work provides a structural basis for further peptide vaccine development against the severe diseases associated with the respiratory syncytial viruses in both cattle and man.