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PubMed · 2924908

Parallel stranded DNA with AT base pairing.

A K Shchyolkina·Lysov YuP·I A Il'ichova·A A Chernyi·Golova YuB·B K Chernov·B P Gottikh·V L Florentiev
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Abstract

The concentration and temperature dependences of the UV and CD spectra of the oligonucleotide 3'-d(ApTpApTpApTpApTpApTp)-O(CH2)6O-5'-d(pApTpApTpApTpApT pApT) (eicosamer) in aqueous solution at pH 7 in the presence of 0.5 M NaCl were studied. At less than 10(-6) M, the eicosamer was shown to form in solution a hairpin with parallel orientation of chains (parallel hairpin). From thermal denaturation profiles [A260(T)] the thermodynamic parameters, delta H degrees, delta S degrees and Tm for parallel hairpin formation were calculated to be -90 +/- 8 kJ/mol. -300 +/- 20 J.mol-1.K-1 and 40.5 degrees C, respectively. The CD spectra of the parallel double helix differed from those of B-form DNA and had characteristic features: decreasing magnitude of the positive maximum at 265 nm and a negative peak at 285 nm.

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AdenineBase CompositionBase SequenceCircular DichroismDNAHot TemperatureNucleic Acid ConformationNucleic Acid DenaturationSpectrophotometry, UltravioletThermodynamicsThymineJournal Article

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A K Shchyolkina, Lysov YuP, I A Il'ichova, A A Chernyi, Golova YuB, B K Chernov, B P Gottikh, V L Florentiev. 1989-02-13. Parallel stranded DNA with AT base pairing.. https://doi.org/10.1016/0014-5793(89)81157-3

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PubMed1992

Purine-cytosine permease of Saccharomyces cerevisiae. Effect of external pH on nucleobase uptake and binding.

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