Sequence specificity in spermine-induced structural changes in CG-oligomers.
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.
Majumder
K
K
Molecular Biophysics Unit, Indian Institute of Science, Bangalore.
Brahmachari
S K
SK
D002942:Circular Dichroism; D009682:Magnetic Resonance Spectroscopy; D009690:Nucleic Acid Conformation / Q000187:drug effects; D009838:Oligodeoxyribonucleotides; D013096:Spermine / Q000494:pharmacology*; D013696:Temperature
D009838:Oligodeoxyribonucleotides; D013096:Spermine