title: Toward Closing the Gap: Quantum Mechanical Calculations and Experimentally Measured Chemical Shifts of a Microcrystalline Lectin.
abstract: NMR chemical shifts are exquisitely sensitive probes for conformation and dynamics in molecules and supramolecular assemblies. Although isotropic chemical shifts are easily measured with high accuracy and precision in conventional NMR experiments, they remain challenging to calculate quantum mechanically, particularly in inherently dynamic biological systems. Using a model benchmark protein, the 133-residue agglutinin from Oscillatoria agardhii (OAA), which has been extensively characterized by us previously, we have explored the integration of X-ray crystallography, solution NMR, MAS NMR, and quantum mechanics/molecular mechanics (QM/MM) calculations for analysis of13Cαand15NHisotropic chemical shifts. The influence of local interactions, quaternary contacts, and dynamics on the accuracy of calculated chemical shifts is analyzed. Our approach is broadly applicable and expected to be beneficial in chemical shift analysis and chemical-shift-based structure refinement for proteins and protein assemblies.
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware , Newark, Delaware 19716, United States.|Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine , 1051 Biomedical Science Tower 3, 3501 Fifth Avenue, Pittsburgh, Pennsylvania 15261, United States.
authors.forename: Matthew
authors.initials: M
authors.lastname: Fritz
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware , Newark, Delaware 19716, United States.|Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine , 1051 Biomedical Science Tower 3, 3501 Fifth Avenue, Pittsburgh, Pennsylvania 15261, United States.
authors.forename: Caitlin M
authors.initials: CM
authors.lastname: Quinn
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware , Newark, Delaware 19716, United States.|Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine , 1051 Biomedical Science Tower 3, 3501 Fifth Avenue, Pittsburgh, Pennsylvania 15261, United States.
authors.forename: Mingzhang
authors.initials: M
authors.lastname: Wang
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware , Newark, Delaware 19716, United States.
authors.forename: Guangjin
authors.initials: G
authors.lastname: Hou
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware , Newark, Delaware 19716, United States.|Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine , 1051 Biomedical Science Tower 3, 3501 Fifth Avenue, Pittsburgh, Pennsylvania 15261, United States.
authors.forename: Xingyu
authors.initials: X
authors.lastname: Lu
authors.affiliation: Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine , 1051 Biomedical Science Tower 3, 3501 Fifth Avenue, Pittsburgh, Pennsylvania 15261, United States.|Department of Structural Biology, University of Pittsburgh School of Medicine , 1051 Biomedical Science Tower 3, 3501 Fifth Avenue, Pittsburgh, Pennsylvania 15261, United States.
authors.forename: Leonardus M I
authors.initials: LMI
authors.lastname: Koharudin
authors.affiliation: Department of Chemistry and Biochemistry, University of Delaware , Newark, Delaware 19716, United States.|Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine , 1051 Biomedical Science Tower 3, 3501 Fifth Avenue, Pittsburgh, Pennsylvania 15261, United States.
authors.forename: Tatyana
authors.identifier: 0000-0002-0346-1131
authors.initials: T
authors.lastname: Polenova
authors.affiliation: Pittsburgh Center for HIV Protein Interactions, University of Pittsburgh School of Medicine , 1051 Biomedical Science Tower 3, 3501 Fifth Avenue, Pittsburgh, Pennsylvania 15261, United States.|Department of Structural Biology, University of Pittsburgh School of Medicine , 1051 Biomedical Science Tower 3, 3501 Fifth Avenue, Pittsburgh, Pennsylvania 15261, United States.
authors.forename: Angela M
authors.identifier: 0000-0001-9072-3525
authors.initials: AM
authors.lastname: Gronenborn
mesh_terms: D000373:Agglutinins / Q000737:chemistry*; D000465:Algorithms; D018360:Crystallography, X-Ray; D056004:Molecular Dynamics Simulation; D019906:Nuclear Magnetic Resonance, Biomolecular; D054300:Oscillatoria / Q000737:chemistry; D011789:Quantum Theory
chemical_list: D000373:Agglutinins