abstract
We present a complete set of experimental approaches for the NMR assignment of powdered tripeptide glutathione at natural isotopic abundance, based on J-coupling and dipolar NMR techniques combined with H-1 CRAMPS decoupling. To fully assign the spectra, two-dimensional (2D) high-resolution methods, such as H-1-C-13 INEPT-HSQC/PRESTO heteronuclear correlations (HETCOR) H-1-H-1, double-quantum (DQ), and H-1-N-14 D-HMQC correlation experiments, have been used. To support the interpretation of the experimental data, periodic density functional theory calculations together with the GIPAW approach have been used to calculate the H-1 and C-13 chemical shifts. It is found that the shifts calculated with two popular plane wave codes (CASTEP and Quantum ESPRESSO) are in excellent agreement with the experimental results.
keywords
H-1-H-1 DOUBLE-QUANTUM; CPMAS-NMR; MOLECULAR-STRUCTURE; CRYSTAL-STRUCTURES; CHEMICAL-SHIFTS; AMINO-ACIDS; SPECTROSCOPY; CRYSTALLOGRAPHY; PACKING; N-14
subject category
Chemistry; Physics
authors
Sardo, M; Siegel, R; Santos, SM; Rocha, J; Gomes, JRB; Mafra, L
our authors
João Rocha
Full Professor
José R. B. Gomes
Principal Researcher
Luís Mafra
Principal Researcher
Mariana Coutinho Sardo
Assistant Researcher
Sérgio Miguel Fernandes dos Santos
Assistant ResearcherProjects
acknowledgements
We thank FCT, QREN, COMPETE, and EU for financial support and postdoc grants for M.S. (SFRH/BPD/65978/2009), RS. (SFRH/EPD/44355/2008) and S.M.S. (SFRH/BPD/64752/2009). The Portuguese NMR Network (RNRMN) is acknowledged for granting access to the 18.8 T NMR Bruker spectrometer at ITQB. FCT is also acknowledged for other funding, R&D Projet: PTDC/QUI-QUI/100998/2008, Programme Ciencia 2007, and PEst-C/CTM/LA0011/2011. L.M. also greatly acknowledges the Campus de Excelencia Internacional Ad Futurism de la Universidad de Oviedo (FUTTALENT Program).