[DNA conformation and thermostability of aqueous solutions of beta-alanine and gamma-aminobutyric acid].
It has been shown that at low concentrations of rare amino acids (from 10(-3) M to 10(-1) M of the substance) stechiometric complexes amino acid -- DNA are formed, which bring about partial substitution of counterions screening phosphate groups and to a change of spatial structure of DNA water molecules. The DNA-solvent molecular interactions are changed, accompanied by an abrupt decrease of helix-coil enthalpy transition which leads to the unwinding of DNA double helix. In the region of amino acid high concentrations (greater than 1-1,5 M) a rise of thermostability and winding of DNA double helix is observed. It has been established that B----C-like conformational transition stimulated by the rise of DNA thermostability is a result of counterions dehydration and the increase of effective ionic strength of the solution which is due to the rise of amino acid-zwitterions content in it.
D000409:Alanine; D000818:Animals; D002417:Cattle; D004247:DNA; D003681:Dehydration; D005998:Glycine; D006358:Hot Temperature; D009690:Nucleic Acid Conformation; D013950:Thymus Gland; D014466:Ultraviolet Rays; D014783:Viscosity; D015091:beta-Alanine; D005680:gamma-Aminobutyric Acid
D015091:beta-Alanine; D005680:gamma-Aminobutyric Acid; D004247:DNA; D000409:Alanine; D005998:Glycine
Konformatsiia i termostabil'nost' DNK v vodnykh rastvorakh beta-alanina i gamma-aminomaslianoĭ kisloty.