(a) Computational study of packing a collagen-like molecule: The lateral packing of a collagen-like molecule has been examined by energy minimization with the ECEPP/3 force field. Two current packing models, the Smith collagen microfibril twisted equilateral pentagon model and the quasi-hexagonal packing model, have been extensively investigated. The quasi-hexagonal packing structure is found to be energetically more favorable than the Smith microfibril by as much as 31.2 kcal/mol of five triple helices. (b) New optimization method for conformational energy calculations on polypeptides: Conformational space annealing: A new optimization method is presented to search for the global minimum-energy conformations of polypeptides. It combines essential aspects of the build-up procedure and the genetic algorithm, and it introduces the important concept of conformational space annealing. When tested on Met-enkephalin, a 24-dihedral angle problem, the accepted global minimum-energy conformation is obtained for all 100 independent runs after about 2600 local minimizations on average. The algorithm is ideally suited for parallel computations, and the parallelization of the algorithm is in progress, which would make it possible to investigate larger polypeptides.
Chiang, Chi-Tung; Shores, Kevin S; Freindorf, Marek et al. (2008) Size-restricted proton transfer within toluene-methanol cluster ions. J Phys Chem A 112:11559-65 |
Kazmierkiewicz, Rajmund; Liwo, Adam; Scheraga, Harold A (2003) Addition of side chains to a known backbone with defined side-chain centroids. Biophys Chem 100:261-80 |
Kazmierkiewicz, Rajmund; Liwo, Adam; Scheraga, Harold A (2002) Energy-based reconstruction of a protein backbone from its alpha-carbon trace by a Monte-Carlo method. J Comput Chem 23:715-23 |
Liwo, Adam; Arlukowicz, Piotr; Czaplewski, Cezary et al. (2002) A method for optimizing potential-energy functions by a hierarchical design of the potential-energy landscape: application to the UNRES force field. Proc Natl Acad Sci U S A 99:1937-42 |
Scheraga, Harold A; Pillardy, Jaroslaw; Liwo, Adam et al. (2002) Evolution of physics-based methodology for exploring the conformational energy landscape of proteins. J Comput Chem 23:28-34 |
Scheraga, Harold A; Vila, Jorge A; Ripoll, Daniel R (2002) Helix-coil transitions re-visited. Biophys Chem 101-102:255-65 |
Pillardy, J; Arnautova, Y A; Czaplewski, C et al. (2001) Conformation-family Monte Carlo: a new method for crystal structure prediction. Proc Natl Acad Sci U S A 98:12351-6 |
Vila, J A; Ripoll, D R; Scheraga, H A (2001) Influence of lysine content and pH on the stability of alanine-based copolypeptides. Biopolymers 58:235-46 |
Pillardy, J; Czaplewski, C; Liwo, A et al. (2001) Recent improvements in prediction of protein structure by global optimization of a potential energy function. Proc Natl Acad Sci U S A 98:2329-33 |
Czaplewski, C; Rodziewicz-Motowidlo, S; Liwo, A et al. (2000) Molecular simulation study of cooperativity in hydrophobic association. Protein Sci 9:1235-45 |
Showing the most recent 10 out of 20 publications