Accession Number : AD0453592

Title :   NUCLEIC ACID INTERACTIONS. V. EFFECTS OF CYCLOBUXINE,

Corporate Author : INDIANA UNIV BLOOMINGTON

Personal Author(s) : Mahler,H. R. ; Dutton,Gary

Report Date : 07 JUL 1964

Pagination or Media Count : 19

Abstract : In aqueous media of low ionic strength (Na+ = 0.006 M) the alkaloid cyclobuxine, a steroidal diamine, exerts a profound effect on the stability of helical polynucleotides (DNA, S-RNA and dAT:dAT). This effect is biphasic in the sense that at low concentrations of the agent (< or = 0.0001) there is stabilization of the native, while ac higher concentrations (> or = 0.0005) there is stabilization of the denatured conformation. In a medium containing 51% methanol only the labilizing interaction persists while at high ionic strength both types of interaction are eliminated. These effects of cyclobuxine are restricted to the reversible order-disorder transition and do not extend to strand separation or re-combination. Cyclobuxine effects the absorption spectrum of DNA and other polynucleotides by producing a generalized hyperchromicity centered at 270 millimicrons. (Author)

Descriptors :   (*RIBONUCLEIC ACIDS, STABILITY), (*NUCLEOTIDES, STABILITY), (*ALKALOIDS, NUCLEIC ACIDS), COMPLEX COMPOUNDS, SOLUTIONS(MIXTURES), IONS, ALKALI METAL COMPOUNDS, SODIUM, POLYMERS, THERMODYNAMICS, PHASE STUDIES, ABSORPTION SPECTRA, REACTION KINETICS, STEREOCHEMISTRY

Distribution Statement : APPROVED FOR PUBLIC RELEASE