13C-NMR chemical shift tensor and hydrogen-bonded structure of glycine-containing peptides in a single crystal

✍ Scribed by Naoto Takeda; Shigeki Kuroki; Hiromichi Kurosu; Isao Ando

• Publisher: Wiley (John Wiley & Sons)
• Year: 1999
• Tongue: English
• Weight: 149 KB
• Volume: 50
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/(sici)1097-0282(199907)50:1<61::aid-bip6>3.0.co;2-9

✦ Synopsis

C-nmr chemical shift tensor components are reported for a 13 C-labeled Gly 1 amide carbonyl carbon of a glycylglycine (Gly 1 Gly 2 ) single crystal, a GlyGly ⅐ HNO 3 single crystal and a GlyGly ⅐ HCl ⅐ H 2 O single crystal, for which the three-dimensional crystal structures have already been determined by x-ray diffraction. The tensor components were measured by changing the angle between the crystal plane and the applied magnetic field by using a goniometer designed in this work for use in conventional C cross-polarization/magic angle spinning nmr probe. From these experimental data, the principal values of the 13 C chemical shift tensor and its directions for the Gly 1 amide carbonyl carbon were determined. It was found that the 13 C chemical shift tensor components (␦ 11 , ␦ 22 , and ␦ 33 ) for the Gly 1 amide carbonyl carbon in GlyGly and GlyGly ⅐ HNO 3 with a ϾNH . . . OACϽ type of hydrogen bond depend on the hydrogen-bond length and the directions of the ␦ 22 components of these peptides are along the hydrogen-bonded ϾCAO bond axis. In addition, the magnitude of the deviation from the bond axis depends on the hydrogen-bond angle. Further, the experimental result for GlyGly ⅐ HCl ⅐ H 2 O with a OOOH . . . OACϽ type of hydrogen bond was discussed.