title: Toward the quantum chemical calculation of nuclear magnetic resonance chemical shifts of proteins.
abstract: Despite the many protein structures solved successfully by nuclear magnetic resonance (NMR) spectroscopy, quality control of NMR structures is still by far not as well established and standardized as in crystallography. Therefore, there is still the need for new, independent, and unbiased evaluation tools to identify problematic parts and in the best case also to give guidelines that how to fix them. We present here, quantum chemical calculations of NMR chemical shifts for many proteins based on our fragment-based quantum chemical method: the adjustable density matrix assembler (ADMA). These results show that (13)C chemical shifts of reasonable accuracy can be obtained that can already provide a powerful measure for the structure validation. (1)H and even more (15)N chemical shifts deviate more strongly from experiment due to the insufficient treatment of solvent effects and conformational averaging.
authors.affiliation: Department of Chemistry and Zukunftskolleg, University of Konstanz, Konstanz D-78457, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Frank
authors.forename: Ionut
authors.initials: I
authors.lastname: Onila
authors.forename: Heiko M
authors.initials: HM
authors.lastname: Möller
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Exner
mesh_terms: D002247:Carbon Isotopes / Q000737:chemistry; D006859:Hydrogen / Q000737:chemistry; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D010455:Peptides / Q000737:chemistry; D011487:Protein Conformation; D011506:Proteins / Q000737:chemistry*; D011789:Quantum Theory; D015203:Reproducibility of Results; D013816:Thermodynamics
chemical_list: D002247:Carbon Isotopes; D010455:Peptides; D011506:Proteins; C508725:Trp-cage peptide; D006859:Hydrogen