Determination of the backbone conformation of secretin by restrained molecular dynamics on the basis of interproton distance data

Eur J Biochem. 1988 Feb 1;171(3):479-84. doi: 10.1111/j.1432-1033.1988.tb13814.x.


The backbone conformation of the 27-residue polypeptide hormone secretin has been investigated using nuclear magnetic resonance spectroscopy and restrained molecular dynamics calculations under conditions where it adopts a fully ordered structure (40% v/v trifluoroethanol). The basis for the restrained molecular dynamics calculations consists of 52 nuclear-Overhauser-enhancement-derived interproton distance restraints involving the NH, C alpha H and C beta H protons. It is shown that convergence to similar extended structures is achieved starting from four different initial structures, namely an alpha helix, a mixed alpha/beta structure, a beta strand and a polyproline helix. The converged structures are made up of short N- and C-terminal strand-like regions and a central region comprising two irregular helices connected by a 'half-turn'.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Energy Transfer
  • Magnetic Resonance Spectroscopy
  • Models, Chemical
  • Protein Conformation
  • Protons
  • Secretin / analysis*
  • Software


  • Protons
  • Secretin