Biopolym. Cell. 1988; 4(4):177-182.
Structure and Function of Biopolymers
Phase surface of the B–Z equilibrium for poly[d(G–C)] solution in coordinates: non-electrolyte fraction, ionic strength, temperature
1Minyat E. E., 2Karapetyan A. T., 2Vardevanyan P. O., 1Ivanov V. I.
  1. Institute of Molecular Biology, Academy of Sciences of the USSR
    Moscow, USSR
  2. Kirovokan State Pedagogical Institute
    Kirovokan, USSR


A fragment of the B and Z interfaces of poly[d(G–C)] within 45–58% ethanol, 10–45 °C and 0.5–3 mM NaCl is a plane. A projection (ethanol fraction, ionic strength) testifies to the occurrence of the reverse Z→B transition with an ionic strength increase, which was predicted by a polyelectrolyte theory but up to now was not observed with poly [d(Q-C)]. Using the polyelecfrolyte model the projection (temperature, ionic strength) permits estimating enthalpy of the Z–B transition: ΔHBZ = – 1.4 kcal/mol.


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