Model of protein folding: incorporation of a one-dimensional short-range (Ising) model into a three-dimensional model.

In this paper, we have incorporated a one-dimensional short-range model into a three-dimensional model for protein folding. It has been applied, by extending the concept of the three-step mechanism for protein folding proposed in our previous paper, to simulate the folding of bovine pancreatic trypsin inhibitor, using a Monte Carlo procedure in all three steps, A, B, and C. The statistical mechanical ensemble treatment of the short-range model serves as a constraint on the Monte Carlo procedure, in which conformational transitions are introduced. The preliminary results of 10 independent Monte Carlo trials indicate that, while folding is achieved, improvements are required in order to account for the correct three-dimensional structure of a globular protein.