PREDICTING SOLVATED PEPTIDE CONFORMATIONS VIA GLOBAL MINIMIZATION OF ENERGETIC ATOM-TO-ATOM INTERACTIONS

A global optimization method is described for identifying the global m inimum energy conformation, as well as lower and upper bounds on the g lobal minimum conformer of solvated peptides. Potential energy contrib utions are calculated using the ECEPP/3 force field model. In consider ing the effects of hydration, two implicit free energy models are comp ared. One method is based an the calculation of solvent-accessible sur face areas, while the other uses information on the solvent-accessible volume of hydration shells. Detailed information on the potential and salvation energy contributions is presented for the terminally blocke d single.residue peptides. In addition, based on a procedure that allo ws the exclusion of domains of the (phi, psi) space, a number of oligo peptide structure prediction problems are considered, and the role of the solvation model in defining global minimum conformations is addres sed. (C) 1998 Elsevier Science Ltd. All rights reserved.