N.m.r. and computer‐simulated conformational analyses of a nonapeptide found in a human salivary proline‐rich glycoprotein
- 1 August 1988
- journal article
- research article
- Published by Wiley in International Journal of Peptide and Protein Research
- Vol. 32 (2) , 130-140
- https://doi.org/10.1111/j.1399-3011.1988.tb00673.x
Abstract
The amino acid sequence G(1)-P(2)-P(3)-P(4)-H(5)-P(6)-G(7)-K(8)-P(9) occurs twice in the proline-rich glycoprotein (PRG) found in human parotid saliva. As part of our efforts to elucidate the structure-function relationships of PRG, this nonapeptide sequence (PRG9) was synthesized for the purpose of conformational analyses by high-resolution proton n.m.r. spectroscopy and computer-modeling. The empirical n.m.r. spectrum differed from the simulated spectrum in that the overall chemical shift locations were displaced from their random coil positions and the five proline residues had non-degenerate C.alpha.H.alpha. protons. Other n.m.r. data indicated that no intramolecular hydrogen-bonding was present in the PRG. In conjunction with X-ray crystallographic data on a triporline-containing model compound (Kartha, g., Ashida, T. and Kakudo, M. (1974) Acta Cryst. B30, 1861-1866), four energy-minimized PRG9 structures were obtained. Two of the structures were energetically unfavorable, while the other two conformations were reasonable. The two most likely structures gave all prolines an S-type ring pucker, the P(2)-P(3)-P(4) sequence as a poly-L-proline II helix, the H(5).vphi. = -90.3.degree., P(6) and P(9) with trans peptide bond orientation, G(7) in an extended state, and the K(8).vphi. = -93.2.degree. or -146.8.degree. for structures #1 and #2, respectively.Keywords
This publication has 21 references indexed in Scilit:
- N.m.r. analyses of the histidine microenvironments in a human salivary proline‐rich glycoproteinInternational Journal of Peptide and Protein Research, 1988
- Conformational analysis of the cholecystokinin C-terminal octapeptide: a nuclear magnetic resonance and computer-simulation approachBiochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology, 1986
- Calibration of the angular dependence of the amide proton-Cα proton coupling constants, 3JHNα, in a globular proteinJournal of Molecular Biology, 1984
- A two-dimensional nuclear overhauser experiment with pure absorption phase in four quadrantsJournal of Magnetic Resonance (1969), 1982
- Structure of the carbohydrate chains of the proline-rich glycoprotein from human parotid salivaBiochemical and Biophysical Research Communications, 1982
- Investigation of complex networks of spin-spin coupling by two-dimensional NMRJournal of Magnetic Resonance (1969), 1981
- Improvement of 2D NOE and 2D correlated spectra by symmetrizationJournal of Magnetic Resonance (1969), 1981
- Spin—spin coupling and the conformational states of peptide systemsProgress in Nuclear Magnetic Resonance Spectroscopy, 1976
- Improved component vicinal coupling constants for calculating side-chain conformations in amino acidsJournal of Magnetic Resonance (1969), 1976
- Vicinal Proton Coupling in Nuclear Magnetic ResonanceJournal of the American Chemical Society, 1963