The electrostatically driven Monte Carlo (EDMC) method has been greatly improved by adding a series of new features. A procedure for cluster analysis of the accepted conformations was included. This information is used in the proedure to guide the search for the global minimum. Also, alternative procedures for generating perturbed conformations - used for sampling the conformational space - were included. These procedures are found to enhance the efficacy of the method by generating a larger number of low-energy conformations. The improved EDMC method has been used to explore the conformational space of a 20-residue polypeptide chain whose sequence corresponds to the membrane-bound portion of melittin. The ECEPP/3 algorithm was used to describe the conformational energy of the chain. After an exhausting search involving 14 independent runs of the procedure, the lowest-energy conformation (LE) (-91.0 kcal/mol) of the entire study was encounagered in four of the runs, while conformations higher in energy by no more than 1.8 kcal/mol were found in the remaining runs with the exception of run 8. LEC is identical to the conformation reported recently by Lee, et.al. (1997) as the lowest-energy conformation obtained in their study using the conformational space annealing method. These results suggest that this conformation may correspond to the global energy minimum of the ECEPP/3 potential function for this specific sequence.

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Biotechnology Resource Grants (P41)
Project #
5P41RR004293-10
Application #
6411731
Study Section
Project Start
2000-12-01
Project End
2001-11-30
Budget Start
1996-10-01
Budget End
1997-09-30
Support Year
10
Fiscal Year
2001
Total Cost
$12,855
Indirect Cost
Name
Cornell University
Department
Type
DUNS #
872612445
City
Ithaca
State
NY
Country
United States
Zip Code
14850
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

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