Results 261 to 270 of about 2,476,402 (307)

Conformational Flexibility of Nucleic Acids

1983
In consideration of the importance of conformational flexibility to the functioning of nucleic acids, NMR studies have been carried out to elucidate aspects of dynamics with molecular Mechanics calculations providing supplementary insight. Analysis of 31P and 13C NMR relaxation data in terms of plausible motions in a DNA helix indicate that winding and
Thomas L. James, Peter Bendel, Jacqueline L. James, Joe W. Keepers, Peter A. Kollman, Aviva Lapidot, Joseph Murphy-Boesch, John E. Taylor   +7 more
openaire   +1 more source

Forces involved in the Conformational Stability of Nucleic Acids

Nature, 1969
ONE of the most important problems in research on nucleic acid is the understanding of the forces which maintain the helical structure. After the elucidation of the double helix by Watson and Crick1, the helical secondary structure of DNA was thought to derive its stability from hydrogen bonding between the base pair. The discovery that polynucleotides
J C, Maurizot, J, Brahms, F, Eckstein
openaire   +2 more sources

Conformation of Viral Nucleic Acids in Situ

1969
Publisher Summary The problems that are discussed in this chapter are confined to viruses, and to be more exact, to the question of similarities and differences between the structure and properties of usual forms of nucleic acids in solution and that of nucleic acids inside viral particles.
openaire   +2 more sources

Conformational properties of nucleic acids in solution

International Journal of Quantum Chemistry, 2009
Principles which govern the conformational properties of nucleic acid structures in aqueous solution are derived from extensive nuclear magnetic resonance studies of nucleic acid components. These principles are then utilized to project the solution conformation of tRNA.
Ramaswamy H. Sarma, Steven S. Danyluk
openaire   +1 more source

Copper(II)-Nucleic acid interactions—A conformational study

Journal of Theoretical Biology, 1979
Abstract The effect of copper complexation upon the conformational angles in mononucleotides and dinucleotides was studied using classical potential energy expressions. The geometrical parameters were taken from crystallographic reports on the base-metal complexes.
J, Bandekar, B K, Sathyanarayana
openaire   +2 more sources

Alternative conformations of a nucleic acid four-way junction

Journal of Molecular Biology, 2000
A crystal structure of a 108 nucleotide RNA-DNA complex containing a four-way junction was solved at 3.1 A resolution. The structure of the junction differs substantially from the "stacked-X" conformation observed previously, due to a 135 degrees rotation of the branches.
J, Nowakowski, P J, Shim, C D, Stout, G F, Joyce   +3 more
openaire   +2 more sources

Conformational principles of nucleic acids

1981
From a conformational standpoint, nucleic acids are enormously complex. In order to rigorously describe, for example, the secondary structure of a repeating polynucleotide such as fibrous poly dA·dT, the values of twelve torsion angles must be ascertained (Figure 1.1); contrast this with a repeating polypeptide where only two conformation angles need ...
openaire   +1 more source

Conformational geometry and vibrational frequencies of nucleic acid chains

Biopolymers, 1975
AbstractNormal coordinate analysis of diethyl phosphate has been made, which predicts all observed Raman frequencies in the range 170–1300 cm−1. The force constants from this calculation have been transferred to a vibrational calculation for a simplified model of the backbone of nucleic acids, which also involves the OPO2−O phosphate group and the ...
E B, Brown, W L, Peticolas
openaire   +2 more sources

Evolution of conformational principles in nucleic acids

International Journal of Quantum Chemistry, 2009
The analysis of conformations of nucleic acids and polynucleotides have been greatly simplified by the important observations that the nucleotide building blocks exhibit two classes of preferred conformations and that the flexibility in the polynucleotide chain resides mainly in the internucleotide PO linkages.
openaire   +1 more source

Nucleic acid analogs: Conformation and their functionalities

Die Makromolekulare Chemie, 1985
Poly-L-, -D-, and -DL-lysine derivatives having pendant nucleic acid bases were prepared by using a polymer modification reaction. Conformation of the polymers was studied by CD and ORD measurements, and the effects of pH of the system, as well as the solvents on the helicity of the polymers were investigated in detail.
openaire   +1 more source