Unique structures formed by pyrimidine-purine DNAs which may be four-stranded.
نویسندگان
چکیده
منابع مشابه
Unique structures formed by pyrimidine-purine DNAs which may be four-stranded.
Pyrimidine-purine DNAs with repeating sequences can be made to undergo a reversible transition to possibly a tetra-stranded complex. Physicochemical characterization of the new structures and model building are consistent with, in the case of d(TC)n-d(GA)n, a tetra-stranded complex forming by the addition of d(GA)n to the remaining space in the major groove of the triple-stranded complex d(TC)n...
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A 30 base pair parallel-stranded (ps) duplex ps-L1.L2 composed of two adjoined purine-purine and purine-pyrimidine sequence blocks has been characterized thermodynamically and spectroscopically. The 5'-terminal 15 residues in both strands ('left-half') consisted of the alternating d(GA)7G sequence that forms a ps homoduplex secondary structure stabilized by d(G.G) and d(A.A) base pairs. The 3'-...
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Nucleotide bases are ubiquitous in living organisms, but the fate of these compounds in natural environments is poorly understood. Here we studied the metabolism of selected purines and pyrimidines in estuarine bacterial assemblages from the Øresund, Denmark. Depletion of nucleotide bases in the incubations was followed by the appearance of urea. The purine guanine and the catabolic intermediat...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 1978
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.75.4.1637