Journal of Biomolecular NMR

, Volume 4, Issue 2, pp 171–180

The 13C Chemical-Shift Index: A simple method for the identification of protein secondary structure using 13C chemical-shift data

  • David S. Wishart
  • Brian D. Sykes
Research Paper

DOI: 10.1007/BF00175245

Cite this article as:
Wishart, D.S. & Sykes, B.D. J Biomol NMR (1994) 4: 171. doi:10.1007/BF00175245


A simple technique for identifying protein secondary structures through the analysis of backbone 13C chemical shifts is described. It is based on the Chemical-Shift Index [Wishart et al. (1992) Biochemistry, 31, 1647–1651] which was originally developed for the analysis of 1Hα chemical shifts. By extending the Chemical-Shift Index to include 13Cα, 13Cβ and carbonyl 13C chemical shifts, it is now possible to use four independent chemical-shift measurements to identify and locate protein secondary structures. It is shown that by combining both 1H and 13C chemical-shift indices to produce a ‘consensus’ estimate of secondary structure, it is possible to achieve a predictive accuracy in excess of 92%. This suggests that the secondary structure of peptides and proteins can be accurately obtained from 1H and 13C chemical shifts, without recourse to NOE measurements.


Chemical shiftSecondary structure13C NMR

Copyright information

© ESCOM Science Publishers B.V 1994

Authors and Affiliations

  • David S. Wishart
    • 1
  • Brian D. Sykes
    • 1
  1. 1.Protein Engineering Network of Centres of Excellence, Department of BiochemistryUniversity of AlbertaEdmontonCanada