A conformational study of glucagon.

@article{Gratzer1968ACS,
  title={A conformational study of glucagon.},
  author={W. Gratzer and G. H. Beaven and H. Rattle and E. Bradbury},
  journal={European journal of biochemistry},
  year={1968},
  volume={3 3},
  pages={
          276-83
        }
}
glucagon is a polypetide of 29 residues, which can be crystallised. Optical rotatory dispersion in dilute neutral, acid and alkaline solution suggests that the polypeptide chain is largely random, but contains about one turn of α-helix, which is eliminated in 6 M guanidine hydrochloride. Using thermal difference spectra, nuclear magnetic resonance, and the temperature-dependence of the optical retatory dispersion as criteria, it appears that glucagon possesses no difined tertiary structure in… Expand
Conformational nature of monomeric glucagon.
It has been shown that monomeric glucagon in aqueous solution does not have a stable globular structure, the conformation changing continuously with change of temperature or concentration ofExpand
Structural studies on polypeptide hormones. I. Fluorescence.
TLDR
Although glucagon appears to be almost completely unorganized in aqueous solution, it is α-helical when crystalline, and the structure of this polypeptide of 29 amino acid residues appears to undergo a helix to coil transition between its crystalline and aqueously states. Expand
Proton NMR studies of the association and folding of glucagon in solution
TLDR
The changes that occur support the belief that the aggregated form of glucagon found in freshly prepared concentrated solutions is a trimer, and the depen- dence of the spectrum on concentration in aqueous solutions is studied. Expand
Secondary structure and dynamics of glucagon in solution.
TLDR
The CD data show that the percentage of alpha-helix decreases with increasing temperature, but the rotational relaxation time of the glucagon increases with temperature, which suggests that the protein's shape changes with temperature in such a way that its volume is larger at 38 degrees C than at 5.5 degrees C. Expand
Presence ot trimers in glucagon solution.
TLDR
It is suggested that the trimeric form of high α-helix content may be equated with the rod-like trimers making up the asymmetric unit in the crystal. Expand
1H nuclear-magnetic-resonance studies of the molecular conformation of monomeric glucagon in aqueous solution.
TLDR
Dilute aqueous solutions of glucagon were investigated by high-resolution 1H nuclear magnetic resonance at 360 MHZ and it was found that the local spatial structure in the fragment 22--25 of glucagons is identical to that observed in the fragments 20--23 of the human parathyroid hormone. Expand
GLUCAGON AND PANCREATIC HORMONE III: X-RAY ANALYSIS, CONFORMATION AND RECEPTOR BINDING
Glucagon is a flexible hormone which has little secondary structure in aqueous solutions at high dilution, but which assumes a helical conformation in more concentrated solutions. The helix isExpand
Lipid‐induced conformational changes in glucagon, secretin, and vasoactive intestinal peptide
TLDR
The helical segment induced by interaction with anionic lipids may play an important physiological role in glucagon, secretin, and vasoactive intestinal peptide. Expand
The Conformation of Glucagon
The biological activity of glucagon is mediated through binding, with high affinity and specificity, to a membrane receptor, implying extensive and well-defined inter-molecular interactions (seeExpand
Structure-function relationships of S-carboxymethyl methionine27 glucagon.
TLDR
Findings indicate that a positive charge rather than bulk on the methionine side chain disrupts the binding of hormone to its receptor and recommends a flexible hormone with nucleation followed by conformational changes for complete binding and activation. Expand
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