Biomaterial Database

[Analysis of defects in the structure of the complex poly(G).poly(C)]. 1994

A L Timkovskiĭ, and Z Baltsarova, and V Brabets

Institute of Biophysics, Czechian Academy of Sciences, Brno, Republic of Czechia.

The concentration of free poly(C) in solution in the course of its interaction with poly(G) as well as in the presence of preformed complex poly(G).poly(C) was measured by differential pulse polarography (DPP) at a mercury dropping electrode. Poly(C) binding with poly(G) was shown to hamper its electrochemical interaction with the mercury electrode and registration by DPP. It was concluded that the extremely low DPP signal from poly(C) in the presence of preformed complex was the result of its interaction with the distortions in the secondary structure of complex molecules containing free guanines. For quantitative testing of these defects, measurement of Tb3+ ion fluorescence was applied. It was shown that preliminary denaturation of the poly(G) secondary structure reduced the amount of structural defects in the complex and restored of complete DPP registration of redundant poly(C) added to this complex. These results show that the combination of DPP and Tb3+ fluorescence measurements permits one to detect at the quantitative level the structural defects in the poly(G).poly(C) complex.

UI	MeSH Term	Description	Entries
D009690	Nucleic Acid Conformation	The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.	DNA Conformation,RNA Conformation,Conformation, DNA,Conformation, Nucleic Acid,Conformation, RNA,Conformations, DNA,Conformations, Nucleic Acid,Conformations, RNA,DNA Conformations,Nucleic Acid Conformations,RNA Conformations
D009691	Nucleic Acid Denaturation	Disruption of the secondary structure of nucleic acids by heat, extreme pH or chemical treatment. Double strand DNA is "melted" by dissociation of the non-covalent hydrogen bonds and hydrophobic interactions. Denatured DNA appears to be a single-stranded flexible structure. The effects of denaturation on RNA are similar though less pronounced and largely reversible.	DNA Denaturation,DNA Melting,RNA Denaturation,Acid Denaturation, Nucleic,Denaturation, DNA,Denaturation, Nucleic Acid,Denaturation, RNA,Nucleic Acid Denaturations
D011066	Poly C	A group of cytosine ribonucleotides in which the phosphate residues of each cytosine ribonucleotide act as bridges in forming diester linkages between the ribose moieties.	Cytosine Polynucleotides,Polycytidylic Acid,Polycytidylic Acids,Acid, Polycytidylic,Acids, Polycytidylic,Polynucleotides, Cytosine
D011068	Poly G	A group of guanine ribonucleotides in which the phosphate residues of each guanine ribonucleotide act as bridges in forming diester linkages between the ribose moieties.	Guanine Polynucleotides,Polyguanylic Acids,Acids, Polyguanylic,Polynucleotides, Guanine
D004563	Electrochemistry	The study of chemical changes resulting from electrical action and electrical activity resulting from chemical changes.	Electrochemistries
D013050	Spectrometry, Fluorescence	Measurement of the intensity and quality of fluorescence.	Fluorescence Spectrophotometry,Fluorescence Spectroscopy,Spectrofluorometry,Fluorescence Spectrometry,Spectrophotometry, Fluorescence,Spectroscopy, Fluorescence