The Effect of Divalent Metal Ions on the Temperature Stability of Poly(I:C) Duplex. (27th June 2020)

• Record Type: Journal Article
• Authors: Usenko, Evgeniya; Valeev, Vladimir; Glamazda, Alexander; Karachevtsev, Victor
• Other Names: Kim Jeongkwon Academic Editor.
• Is Part Of: Journal of spectroscopy. Volume 2020(2020)
• Publication Date: 2020-06-27
• Subjects: Spectrum analysis -- Periodicals; 543.505
• DOI: 10.1155/2020/8850214
• Languages: English
• ISSNs: 2314-4920

Abstract

Abstract : The effect of divalent ions on the thermal stability of the double-stranded polynucleotide polyinosinic:polycytidylic acid (poly(I:C)) in a buffer solution (pH 7) was studied by UV absorption spectroscopy and thermal denaturation by measuring the absorbance at 260 nm. The concentration dependence of the polynucleotide melting temperature ( T m ) in the presence of metal ions (2.5 × 10 −6 –10 −2 M) was obtained. It was found that the duplex thermal stability grew gradually upon an increase of Ca 2+ and Mn 2+ concentration. The thermal stability of the duplex in the presence of Cd 2+, Ni 2+, and Zn 2+ rises up to an ion concentration of about 10 −4 M and further falls. In contrast to these ions, the addition of Cu 2+ to the solution leads to a sharp decline in Т m of the duplex at a concentration above 10 −5 M. The observed difference in the influence of metal ions on the poly(I:C) thermal stability is explained by the different affinity of these ions to both the phosphate groups and the nitrogenous bases of the polynucleotides. Based on the analysis of the T m concentration dependence, the dominant binding of each ion to the specific polynucleotide components was proposed.