Computed and experimental chemical shift parameters for rigid and flexible YAF peptides in the solid state

0374912 - ÚMCH 2012 RIV US eng J - Článek v odborném periodiku
Pawlak, T. - Trzeciak-Karlikowska, K. - Czernek, Jiří - Ciesielski, W. - Potrzebowski, M. J.
Computed and experimental chemical shift parameters for rigid and flexible YAF peptides in the solid state.
Journal of Physical Chemistry B. Roč. 116, č. 6 (2012), s. 1974-1983. ISSN 1520-6106. E-ISSN 1520-5207
Grant CEP: GA MŠMT 2B08021
Výzkumný záměr: CEZ:AV0Z40500505
Klíčová slova: NMR * CST * DFT
Kód oboru RIV: CB - Analytická chemie, separace
Impakt faktor: 3.607, rok: 2012

DFT methods were employed to compute the 13C NMR chemical shift tensor (CST) parameters for crystals of YAF peptides (Tyr-Ala-Phe) with different stereochemistry for the Ala residue. Tyr-D-Ala-Phe 1 crystallizes in the C2 space group while Tyr- L-Ala-Phe crystallizes in either the P21212 space group (2a) or the P65 space group (2b). PISEMA MAS measurements for samples with a natural abundance of 1H and 13C nuclei and 2H QUADECHO experiments for samples with deuterium labeled aromatic rings were used to analyze the geometry and time scale of the molecular motion. The theoretical values of the CST were obtained for isolated molecules (IM) and clusters employing the ONIOM approach. The experimental 13C δii parameters for all of the samples were measured via a 2D PASS sequence. We show that the quality of the 13C σii/13C δii correlations, when properly interpreted, can be a source of important information about local molecular motions.
Trvalý link: http://hdl.handle.net/11104/0006915