title: Characterization of the conformational domains of bradykinin by computational methods.
abstract: The AMBER 4.0 force field was used to perform a characterization of the conformational profile of the nonapeptide bradykinin. A thorough conformational search was carried out using molecular dynamics as sampling technique, by computing cycles of high (900 K) and low (300 K) temperature trajectories. A total of 2400 minima were generated and subsequently clustered using the root-mean-square of the backbone dihedral angles as criterium. After the use of a tolerance value of 20 degrees, the conformations were clustered in 233 unique conformations with energies up to 40 kcal/mol above the lowest minimum. The analysis of the low-energy conformations indicate that the peptide exhibits a high tendency to adopt a beta-turn at the C-terminus and a propensity to adopt a bent structure at the N-terminus. These results are in agreement with the experimental evidence reported in the literature and provide detailed information necessary to understand the conformational preferences of the peptide.
authors.affiliation: Department d'Enginyeria Quimica, Universitat Politecnica de Catalunya, Barcelona, Spain.
authors.forename: J J
authors.initials: JJ
authors.lastname: Perez
authors.forename: Y M
authors.initials: YM
authors.lastname: Sanchez
authors.forename: N B
authors.initials: NB
authors.lastname: Centeno
mesh_terms: D000595:Amino Acid Sequence; D001920:Bradykinin / Q000737:chemistry*; D002942:Circular Dichroism; D006860:Hydrogen Bonding; D015394:Molecular Structure; D011487:Protein Conformation; D013816:Thermodynamics
chemical_list: D001920:Bradykinin