par De Coen, Jean-Louis 
Référence Journal of Molecular Biology, 49, 2, page (405-414)
Publication Publié, 1970-04
Référence Journal of Molecular Biology, 49, 2, page (405-414)
Publication Publié, 1970-04
Article révisé par les pairs
| Résumé : | The folding of the polypeptide chain, as it grows on the ribosome, has been simulated with the aid of a computer. Calculations of conformational energy have been carried out at each stage of the synthesis. A simple model has been considered in detail. It consists of a polyalanine chain containing some spots where hydrogen bond formation is prevented. It is assumed that, at the beginning of the synthesis, the peptide searches for a conformation corresponding to a deep trough of minimum energy. By calculating the energy of a great number of sterically allowed structures it is shown that such a state, which is the result of the co-operative effect of various forces, arises only when the peptide has grown to about six residues. The assumption is made that at this stage of the synthesis the amino-terminal peptide freezes and does not change its conformation as the chain grows further. The frozen structure is thereafter considered as a germ of crystallization upon which the rest of the polypeptide will continue to grow. In this way, a metastable state is constructed. Comparison with experimental data indicates that the calculated conformation does in fact exist in a known protein. © 1970. |
