title: [Possibility of spectrophotometric registration of conformation changes of polynucleotides in the system poly(A:U)-pyronine G].
abstract: The spectrophotometric study of poly(A:U) (90:10)-pyronine G (PG) complex formation has shown that the interaction of PG with polyriboadenylic acid pH = 6.3 is not changed despite the presence of 10% of pyrimidine bases in the single-stranded polynucleotide chain. Analysis of the dependence of complex formation versus acidity increase in the visible spectral range suggests that there are two forms of protonated double-stranded helix of poly(A:U) (90:10), as well as poly(A). PG dye does not interact with the more strongly protonated form by means of the aggregation. There is a strong resemblance between the interaction of PG with the less strongly protonated form and with the neutral single-stranded form of poly(A:U) (90:10). One can determine pH-transition ranges of the two poly(A:U) (90:10) protonated forms using the difference in their interaction with PG at low concentrations of polynucleotide.
authors.forename: E B
authors.initials: EB
authors.lastname: Kruglova
authors.forename: T L
authors.initials: TL
authors.lastname: Zinenko
mesh_terms: D006863:Hydrogen-Ion Concentration; D009690:Nucleic Acid Conformation; D011063:Poly A-U; D011754:Pyronine; D013056:Spectrophotometry, Ultraviolet; D014966:Xanthenes
chemical_list: D014966:Xanthenes; D011063:Poly A-U; D011754:Pyronine
vernacular_title: Vozmozhnost' spektrofotometricheskoĭ registratsii konformatsionnykh izmeneniĭ polinukleotida v sisteme poli(A:U)-pironin G.