Skip to main content
Log in

Stereochemical criteria for polypeptide and protein chain conformations

Part I. Evaluation of helical parameters

  • Published:
Proceedings of the Indian Academy of Sciences - Section A Aims and scope Submit manuscript

Summary

A large number of configurations are possible for a polypeptide structure depending upon the relative orientations of the two peptide groups linked at anα-carbon atom. If the linkages at theα-carbon atoms are identical, then the structure assumes a regular helical form. Such a regular helical structure can be specified by two parametersφ, φ′ which are the angles of rotation of the two groups about the N—αC andαC—C′ bonds meeting at anα-carbon atom. In this paper, a method of evaluating the helical parameters of a structure, namely, the number of residues per turnn, the unit translation along the axis of the helixh and the direction cosines of the helical axis with respect to a suitably chosen co-ordinate system, is described making use of rotation matrices. The evaluation has been done for three different values of the angle\(N\widehat{aC}C'\) at theα-carbon atom, namely, 105°, 110° and 115°. The results are shown graphically in the form of curves for constantn and constanth in theφ − φ′ plane.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  • Bragg, W. L., Kendrew, J. C. and Perutz, M. F...Proc. Roy. Soc. (London), 1950,203 A, 321.

    Google Scholar 

  • Corey, R. B. and Pauling, L... Ibid., 1953,141 B, 10.

    Google Scholar 

  • Donohue, J...Proc. Natl. Acad. Sci., U.S., 1953,39, 470.

    Article  Google Scholar 

  • Huggins, M. L...Chem. Revs., 1943,32, 195.

    Article  Google Scholar 

  • Miyazawa, T...J. Poly Sci., 1961,55, 215.

    Article  Google Scholar 

  • Mizushima, S. and Shimanouchi, T.Advances in Enzymology, 1961,23, 1.

    Article  Google Scholar 

  • Pauling, L., Corey, R. B. and Branson, H. R.Proc. Natl. Acad. Sci., U.S., 1951,37, 205.

    Article  Google Scholar 

  • Ramakrishnan, C. ..Proc. Ind. Acad. Sci., 1964, to be published.

  • Sasisekharan, V... InCollagen, Ed. by N. Ramanathan, John Wiley, New York, 1962, p. 39.

    Google Scholar 

  • Shimanouchi, T. and Mizushima, S.J. Chem. Phys., 1955,23, 707.

    Article  Google Scholar 

  • Whittaker, E. T. .. InA Treatise on the Analytical Dynamics of Particles and Rigid Bodies, Cambridge University Press, 1952, p. 8.

Download references

Author information

Authors and Affiliations

Authors

Additional information

Communicated by Prof. G. N. Ramachandran,f.a.sc.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Ramakrishnan, C. Stereochemical criteria for polypeptide and protein chain conformations. Proc. Indian Acad. Sci. 59, 327–343 (1964). https://doi.org/10.1007/BF03046447

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF03046447

Keywords

Navigation