title: The interaction of polyamines with DNA: a 23Na NMR study.
abstract: The interaction between a variety of polyamines, both naturally occurring and synthetic, and calf thymus DNA has been studied using 23Na NMR. The relaxation behaviour of 23Na reflects the extent of interaction of Na+ with DNA phosphate groups and therefore the extent of charge neutralisation of DNA phosphate groups (P) by polyamine amino and imino groups (N) in solutions of DNa, polyamine and Na+. The studies reveal that whereas spermine and spermidine are capable of expelling nearly all of the Na+ ions from DNA at N/P approximately 1, diamines such as putrescine and homologues of spermine and spermidine are capable of neutralising only roughly 50% of DNA phosphates. The results provide a challenge to current models of DNA-polyamine interactions.
mesh_terms: D000818:Animals; D002417:Cattle; D004247:DNA / Q000378:metabolism*; D004563:Electrochemistry; D009682:Magnetic Resonance Spectroscopy; D011073:Polyamines / Q000378:metabolism*; D012964:Sodium; D013950:Thymus Gland
chemical_list: D011073:Polyamines; D004247:DNA; D012964:Sodium