A Theory for the Helix/Coil Transition of Oligopeptide Chain Dimer

올리고펩티드 사슬이합체의 헬릭스-코일 전이 이론

  • Kim, Younggu (Department of Chemistry, Seoul National University) ;
  • Pak, Hyungsuk (Department of Chemistry, Seoul National University)
  • 김영구 (서울대학교 자연과학대학 화학과) ;
  • 박형석 (서울대학교 자연과학대학 화학과)
  • Published : 19951000


A theory of the helix/coil transition for $\alpha$ helical dimer such as $\alpha$ tropomycin and paramycin is developed. The treatment differs from those formulated previously for oligopeptide dimer which is explained by the matrix method using Zimm-Bragg parameter: In the present treatement, it is explained by the zipper model which can account for the dangling H-bond. We calculate the fractional helicity in $\alpha$ helical dimer as a function of helix initiation $constant(\sigma)$, helix stability constant(${\xi}$) and hydrophobic interaction parameter(w). For $\alpha$ tropomycin, the helix stability profile is also calculated. The transitions of this oligomer due to the change of temperature and the concentration of oligopeptide involve simultaneous dissociation of the dimer. The transitions of dimers which have cross-linked S-S bonds or have long chains don't occur, because they keep always helical structures. The transitons due to the concentration of the oligopeptides are steeper than those due to the chain length or temperature.



  1. J. Chem. Phys. v.31 Zimm, B. H.;Bragg, J. K.
  2. Biophys. J. v.36 Johnson, M. L.;Correia, J. J.;Yphantis, D. A.;Halvor, H. R.
  3. J. Ameri, Chemi. Soci. v.114 Fairmann, R.;Spencer, J. A.;Degrado, W. F.
  4. Biochemistry v.4 Holtzer, A.;Clark, R.;Lowey, S.
  5. Comp. Biochem. Physiolo. v.69B Crmmins, D.;Isomm, L.;Holtzer, A.
  6. Biochemistry v.20 Wu, C. S.;Ikeda, K.;Yang, J. T.
  7. Stastistical Mechanics Mayer, J.;Mayer, M.
  8. Protein Science v.2 Zhu, B.;Zhou, N. E.;Kay, C. M.;Hodges, R. S.
  9. Macromolecules v.16 Holtzer, M. E.;Holtzer, A.;Skolnick, J.
  10. Proc. Natl. Acad. Sci. USA v.30 Pauling, L.;Corey, R. B.;Branson, H. R.
  11. Protein Data Bank #67
  12. Biochem. J. v.6 David, B.;Fasman, G. D.
  13. J. Polymer Sci. v.23 Doty, P. et al.
  14. Proc. Natl. Acad. Sci. USA v.69 Sodek, J.;Hodegs, R. S.;Smillie, L. B.
  15. Science v.254 O'shera, E. K.;Klemm, J. D.;Kim, P. S.;Alber, T.
  16. Proc. Natl. Acad. Sci. U. S. A. v.64 Goodman, M. et al.
  17. Macromolecules v.15 Skolnick, J.;Holtzer, A.
  18. Macromolecules v.18 Skolnick, J.;Holtzer, A.
  19. J. Amer. Chem. Soci. v.79 Cohen, C.;Szent-Gyorgyri, A. G.
  20. Biopolymers v.24 Mattice, W. L.
  21. Macromolecules v.5 Platzer, K. E. B. et al.
  22. Aust. J. Biol. Soci. v.29 Woods, E.
  23. J. Chem. Phys. v.34 Lifson, S.;Loig, A.
  24. Science v.250 O'Neil, K. T.;Degrado, W. F.