title: A general and efficient approach for NMR studies of peptide dynamics in class I MHC peptide binding grooves.
abstract: T-Cell receptor recognition of peptides bound by major histocompatibility complex (MHC) proteins initiates a cellular immune response. Dynamics of peptides within MHC binding grooves can influence TCR recognition, yet NMR studies which could address this rigorously have been hindered by the expense of isotopically labeled peptides and the large size of peptide-MHC complexes. Here we describe a methodology for characterizing peptide dynamics within MHC binding grooves via NMR, using a biosynthetic approach for producing labeled peptide. With the Tax(11-19) peptide bound to the human class I MHC HLA-A*0201, we demonstrate that peptide generated in this manner can be well characterized in MHC binding grooves by NMR, providing opportunities to more precisely study the role of peptide dynamics in TCR recognition. Demonstrating the utility of such studies, the data with the Tax(11-19) peptide indicate the presence of slow conformational exchange in the peptide, supporting an "induced-fit" style TCR binding mechanism.
authors.affiliation: Department of Chemistry and Biochemistry and Walther Cancer Research Center, 251 Nieuwland Science Hall, University of Notre Dame, Notre Dame, Indiana 46556, USA.
authors.forename: Francis K
authors.initials: FK
authors.lastname: Insaidoo
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Zajicek
authors.forename: Brian M
authors.initials: BM
authors.lastname: Baker
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D002247:Carbon Isotopes; D016356:Gene Products, tax / Q000737:chemistry; D015395:Histocompatibility Antigens Class I / Q000737:chemistry* / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000737:chemistry* / Q000276:immunology; D006801:Humans; D007553:Isotope Labeling; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008285:Major Histocompatibility Complex; D008958:Models, Molecular; D009842:Oligopeptides / Q000737:chemistry; D011487:Protein Conformation; D011948:Receptors, Antigen, T-Cell / Q000737:chemistry / Q000276:immunology
chemical_list: D002247:Carbon Isotopes; D016356:Gene Products, tax; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; D009842:Oligopeptides; D011948:Receptors, Antigen, T-Cell; C518303:leucyl-leucyl-phenylalanyl-glycyl-tyrosyl-prolyl-valyl-tyrosyl-valine