title: [Differentiation of the spatial mobility of lysine residues in immunoglobulin G using spin labels].
abstract: Some dynamic and conformational changes of Lys residue in molecules of human IgG have been studied by the spin label method using N-(1-oxyl-2,2,5,5-tetramethyl-3- pyrrolidinyl)maleimide, known to selectively modify the Lys residue in human IgG. The value of tau 20 C of the spin labelled IgG was found to be 26 +/- 2 ns, what is known to be characteristic for the labelling of the peptide residue in IgG. It has also been found that the spin-labelled Lys residues exist in two forms with different mobility and rigidity with the ratio of mobile to rigid forms of 3:1. The hypothesis that the reason for immobility of Lys residues in IgG lies in their drawing in the H-bonds formation is being proved. The study by the spin label method has shown that the often observed mobilization of the EPR spectra of the spin labelled IgG is caused by the process of autolysis in the stored samples. The use of the phenylmethylsulfonylfluoride can completely eliminate this phenomena.
authors.forename: V P
authors.initials: VP
authors.lastname: Timofeev
authors.forename: V A
authors.initials: VA
authors.lastname: Lapuk
authors.forename: B A
authors.initials: BA
authors.lastname: Samarianov
mesh_terms: D004578:Electron Spin Resonance Spectroscopy; D006860:Hydrogen Bonding; D007074:Immunoglobulin G / Q000737:chemistry*; D008239:Lysine / Q000032:analysis*; D013113:Spin Labels
chemical_list: D007074:Immunoglobulin G; D013113:Spin Labels; D008239:Lysine
vernacular_title: Differentsiatsiia prostranstvennoĭ podvizhnosti ostatkov lizina v immunoglobuline G metodom spin-metki.