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PubMed · 2764957

Sequence specificity in spermine-induced structural changes in CG-oligomers.

K Majumder·S K Brahmachari
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Abstract

The role of spermine in inducing A-DNA conformation in deoxyoligonucleotides has been studied using CCGG and GGCC as model sequences. It has been found that while CCGG adopts an alternating B-DNA conformation in low salt solution at low temperature, addition of spermine to this medium induces a B --greater than A transition. In contrast, the A-DNA-like structure of GGCC in low salt solution at low temperature does not change under the influence of spermine. This suggests a sequence-dependent behaviour of spermine. Further these results suggest that the A-DNA conformation observed in the crystals of d(iCCGG) and d(GGCC)2 might have been due to the presence of spermine in the crystallization cocktail.

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Circular DichroismMagnetic Resonance SpectroscopyNucleic Acid ConformationOligodeoxyribonucleotidesSpermineTemperatureJournal ArticleResearch Support, Non-U.S. Gov't

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K Majumder, S K Brahmachari. 1989. Sequence specificity in spermine-induced structural changes in CG-oligomers.. https://pubmed.ncbi.nlm.nih.gov/2764957/

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