| 초록 |
Proteins are linear heteropolymers consisting of 20 possible types of monomeric units (amino acid residues) and fold into their unique native structure within time scale of 1 msec ~ 1 min. This rapid search for the unique structure in the conformational space is only possible when both of thermodynamic and kinetic requirements are satisfied. For proteins consisting of relatively small number of residues, it has been suggested that the pronounced energy minimum in the energy spectrum of conformations is the necessary condition for thermodynamic and kinetic foldicity of the proteins. Despite this knowledge, a systematic study about the factors governing the kinetics of protein folding still remains incomplete. In this study, we investigate the topological effects on folding kinetics in terms of contact order, which is defined as the averaged sequence separation between contacting residues. Using a folding simulation based on a lattice Monte Carlo technique, the folding rates are measured as a function of the contact order of model proteins and the results are discussed in connection with the free energy landscape. |
