Biopolym. Cell. 1989; 5(3):43-48.
Structure and Function of Biopolymers
Stability of secondary structure of the oligonucleotide substrates. The effect of Ecodam DNA-methylase
1, 2Rechkunova N. I., 2Lokhov S. G., 1Gorbunov Yu. A., 1Zinoviev V. V., 3Buryanov Ya. I., 1Malygin E. G.
  1. All-Union Research Institute of Molecular Biology
    Koltsovo, Novosibirsk Region, USSR
  2. Institute of Bioorganic Chemistry, Siberian Branch of the Academy of Sciences of the USSR
    Novosibirsk, USSR
  3. Institute of Biochemistry and Physiology of Microorganisms, Academy of Sciences of the USSR
    Pushchino, Moscow Region, USSR


Oligonucleotide complexes containing various defects in Ecodam methylase recognition site have been investigated for their stability. Partial duplex structure of the single-stranded 20-base long oligonucleotide containing a self-complementary hexanucleotide sequence is observed only below 5 °C. Other complexes are melting within the narrow temperature range of 22–31 °C in 30 mM of potassium-phosphate buffer, pH 7.8. Presence of Ecodam methylase results in an increase of complex melting point at least by 5 °C.


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