Structural Prediction of Peptides Bound to MHC Class I
Autor: | Jean-Charles Cerottini, Theres Fagerberg, Olivier Michielin |
---|---|
Rok vydání: | 2006 |
Předmět: |
Models
Molecular chemistry.chemical_classification Binding Sites HLA-A Antigens biology Histocompatibility Antigens Class I Ab initio Solvation Genes MHC Class I Water Peptide Human leukocyte antigen Protein Structure Tertiary Molecular dynamics Crystallography chemistry Structural Biology MHC class I Cluster (physics) biology.protein Humans Peptides Molecular Biology Conformational isomerism Algorithms |
Zdroj: | Journal of Molecular Biology. 356:521-546 |
ISSN: | 0022-2836 |
DOI: | 10.1016/j.jmb.2005.11.059 |
Popis: | An ab initio structure prediction approach adapted to the peptide-major histocompatibility complex (MHC) class I system is presented. Based on structure comparisons of a large set of peptide-MHC class I complexes, a molecular dynamics protocol is proposed using simulated annealing (SA) cycles to sample the conformational space of the peptide in its fixed MHC environment. A set of 14 peptide-human leukocyte antigen (HLA) A0201 and 27 peptide-non-HLA A0201 complexes for which X-ray structures are available is used to test the accuracy of the prediction method. For each complex, 1000 peptide conformers are obtained from the SA sampling. A graph theory clustering algorithm based on heavy atom root-mean-square deviation (RMSD) values is applied to the sampled conformers. The clusters are ranked using cluster size, mean effective or conformational free energies, with solvation free energies computed using Generalized Born MV 2 (GB-MV2) and Poisson-Boltzmann (PB) continuum models. The final conformation is chosen as the center of the best-ranked cluster. With conformational free energies, the overall prediction success is 83% using a 1.00 Angstroms crystal RMSD criterion for main-chain atoms, and 76% using a 1.50 Angstroms RMSD criterion for heavy atoms. The prediction success is even higher for the set of 14 peptide-HLA A0201 complexes: 100% of the peptides have main-chain RMSD valuesor =1.00 Angstroms and 93% of the peptides have heavy atom RMSD valuesor =1.50 Angstroms. This structure prediction method can be applied to complexes of natural or modified antigenic peptides in their MHC environment with the aim to perform rational structure-based optimizations of tumor vaccines. |
Databáze: | OpenAIRE |
Externí odkaz: |