title: [Method for calculation of low-energy conformations of alpha-helical pairs of globular proteins].
abstract: The computer model of folding of two alpha-helices of globular proteins was developed. The radicals of amino acids were approximated by spheres with centers located in C beta-atoms. The functional of energy took into account the hydrophobic interactions of alpha-helices, electrostatic contacts of charged and polar side groups of amino acid, Van der Waals' interactions. The conformations with minimum energies of two-helical superstructures G--H from alpha- and beta-chains of horse hemoglobin, sperm whale myoglobin, and erythrocruorin were computed. They have mean deviation 0.7--1.8 A from native conformations of these proteins. Hence, at the self-organization process alpha-helices firstly are "roughly" oriented by hydrophobic interactions, but the choice of stable conformation occurs by Van der Waals' and electrostatic interactions. On this stage the low-energy conformation becomes "frozen" and cannot be significantly rearranged later. The mutual orientation of secondary protein structures are determined mainly by amino acid radical volumes, their hydrophobicity and charge.
mesh_terms: D000818:Animals; D004902:Erythrocruorins; D005916:Globulins; D006454:Hemoglobins; D046911:Macromolecular Substances; D008433:Mathematics; D008722:Methods; D008958:Models, Molecular; D009211:Myoglobin; D011487:Protein Conformation; D014907:Whales
chemical_list: D004902:Erythrocruorins; D005916:Globulins; D006454:Hemoglobins; D046911:Macromolecular Substances; D009211:Myoglobin
vernacular_title: Metod rascheta nizkoénergeticheskikh konformatsiĭ par al'fa-spiraleĭ v globuliarnykh belkakh.