Artículos de revistas
Pressure Dependence of N-15 Chemical Shifts in Model Peptides Ac-Gly-Gly-X-Ala-NH2
Fecha
2012Registro en:
MATERIALS, BASEL, v. 5, n. 10, pp. 1774-1786, OCT, 2012
1996-1944
10.3390/ma5101774
Autor
Koehler, Joerg
Erlach, Markus Beck
Crusca Júnior, Edson
Kremer, Werner
Munte, Claudia E.
Kalbitzer, Hans Robert
Institución
Resumen
High pressure NMR spectroscopy has developed into an important tool for studying conformational equilibria of proteins in solution. We have studied the amide proton and nitrogen chemical shifts of the 20 canonical amino acids X in the random-coil model peptide Ac-Gly-Gly-X-Ala-NH2, in a pressure range from 0.1 to 200 MPa, at a proton resonance frequency of 800 MHz. The obtained data allowed the determination of first and second order pressure coefficients with high accuracy at 283 K and pH 6.7. The mean first and second order pressure coefficients <B-1(15N)> and <B-2(15N)> for nitrogen are 2.91 ppm/GPa and -2.32 ppm/GPa(2), respectively. The corresponding values <B-1(1H)> and <B-2(1H)> for the amide protons are 0.52 ppm/GPa and -0.41 ppm/GPa(2). Residual dependent (1)J(1H15N)-coupling constants are shown.