, Volume 13, Issue 8, pp 301–307 | Cite as

Zeitbedarf der Längsteilung von miteinander verzwirnten Fadenmolekülen

  • Werner Kuhn


The time requirement is treated for a longitudinal fission by Brownian movement of a very long particle consisting of two or more filaments twisted a great number of times round each other to form a double spiral. It is shown that a comparatively swift disintegration is obtained by partial rotation or torsion round the axis of the spiral, resulting in a loosing of the spiral structure and subsequent separation of the constituents by translational Brownian movement. The time required to separate a double spiral consisting of about 900 turns of a height of 3.4 × 10−7 cm and a radius of 10−7 cm, thus having a length of 3 × 10−4 cm being realized approximately by deoxyribonucleic acid is found by this mechanism to be about 50 to 80 s. The time required to undo the same spiral by unwrapping it turn by turn would be about 150 days. The result of the considerations is related to observations published byAlexander andSteacy on deoxyribonucleic acid. An additional remark stresses the importance of stereochemical asymmetry for the practicability of the mechanism and therefore the importance of optical activity for the time requirement of such disintegrations or transformations of high polymer material occurring in living organisms.


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  1. 1.
    F. H. Crick undJ. D. Watson, Proc. Roy. Soc. [A]223, 80 (1954), Nature171, 737 (1953).Google Scholar
  2. 2.
    P. Doty, M. E. Reichmann, S. A. Rice undC. A. Thomas, J. Amer. chem. Soc.76, 3047 (1954). Siehe auchR. E. Franklin undR. G. Gosling, Nature171, 740 (1953);172, 153 (1953), sowieM. H. F. Wilkins, A. R. Stokes undH. R. Wilson, Nature171, 739 (1953).CrossRefGoogle Scholar
  3. 3.
    P. Alexander undK. A. Stacey, Trans. Farad. Soc.50, 303 (1954); Biochem. J.60, 194 (1954); Nature176, 162 (1955).CrossRefGoogle Scholar
  4. 5.
    Für eine Zusammenstellung siehe zum Beispiel:W. Kuhn, H. Kuhn undP. Buchner, Ergebn. exakt. Naturwiss.25, 1 (1951), insbes. S. 16 und 88.Google Scholar
  5. 5a.
    W. Kuhn, Z. physik. Chem. [A]161, 1 (1932).Google Scholar
  6. 6.
    Siehe die nachfolgende Mitteilung vonP. Alexander undK. A. Stacey.Google Scholar
  7. 7.
    A. Rich undF. H. Crick, Nature176, 915 (1955).PubMedGoogle Scholar
  8. 7a.
    P. M. Cowan, S. M. Gavin undA. C. T. North, Nature176, 1062 (1955).PubMedGoogle Scholar
  9. 7b.
    H. Zahn, Angew. Chem.64, 295 (1952).Google Scholar
  10. 7c.
    G. N. Ramachandran undG. Kartha, Nature176, 593 (1955).PubMedGoogle Scholar
  11. 7d.
    H. Boedtker undP. Doty, J. Am. chem. Soc.78, 4267 (1956).CrossRefGoogle Scholar
  12. 8.
    Für die, soweit mir bekannt ist, erstmalige Begründung dieser Beziehung sieheW. Kuhn, Helv. chim. Acta35, 1684 (1952), insbesondere Gl. (10a) daselbst S. 1692.Google Scholar

Copyright information

© Birkhäuser Verlag 1957

Authors and Affiliations

  • Werner Kuhn
    • 1
  1. 1.Physikalisch-Chemisches Institut der Universität BaselSwitzerland

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