Conformational preferences of two peptides DYASL and DYA from haemagglutinin of influenza virus and their possible role in the initiation of protein folding

The conformational preferences of two peptides DYASL and DYA from haemagglutinin of influenza virus were studied using PCILO programme. This was done to understand the possible role of DYAS in the initiation of protein folding and to understand the contribution of the fourth residue serine in the formation of turn. Our results indicate that this sequence shows an inherent preference for turn conformation, with a stabilizing Asx turn. DYA with NH group in the C-terminal protection models a type I beta turn more closelythan DYAS, because serine has a weak potential for turn conformation.