RESUMO
The interaction between poly(9-vinyladenine) (PVAd) and poly[r(U)] was investigated by means of uv, CD, 1H-, and 31P-nmr spectroscopies. The interaction was dependent on the molecular weight of PVAd determined by uv and CD spectroscopies. Based on imino proton nmr, it was clearly found that PVAd formed the complex with poly[r(U)] by complementary hydrogen bonding. The interaction of PVAd with double- and triple-stranded helices of RNA was also investigated by uv melting behavior and 31P-nmr spectroscopy. The results suggested that PVAd could not interact with the double-stranded poly[r(A)].poly[r(U)] but did with the triple-stranded RNA.
Assuntos
Adenina/análogos & derivados , Poli A-U/química , Poli A/química , Poli U/química , Polivinil/química , RNA/química , Adenina/química , Dicroísmo Circular , Espectroscopia de Ressonância Magnética/métodos , Conformação de Ácido Nucleico , Desnaturação de Ácido Nucleico , Espectrofotometria Ultravioleta/métodosRESUMO
The nucleic acid analogues poly(9-vinyladenine) (PVAd), poly(9-adenylethyl methacrylate) and poly(thymylethyl methacrylate) (PTM) were chemically bonded to porous silica gel, which had been pretreated with 3-trimethoxysilylpropyl methacrylate, by free radical copolymerization to produce novel packing materials for affinity chromatographic columns. The columns separated nucleosides and nucleotide dimers on the basis of hydrophobic interaction using an aqueous buffer and complementary hydrogen bonding interaction in methanol as an eluent. The PVAd- and PTM-silica gel columns gave a nucleobase-selective separation of oligonucleotides differing in length from mixtures of oligoadenylic and oligouridylic acids. On the PVAd-silica gel column terminal phosphate isomers of oligouridylic acid up to seven mer were resolved and the elution order of the isomers was different from that on an ODS column.