The effect of charge on the volume change of DNA binding with intercalator DAPP.
To study the effect of ligand charge on DNA-ligand binding, we measured the difference in volume change of the noncovalent complex formed between calf thymus DNA and the charged and uncharged form of 3,8-diamino-6-phenylphenanthridine (DAPP). We found that the volume change for binding with the charged DAPPH+ is about 7.8 +/- 1.5 cm3 mol(-1) more positive than with the neutral DAPP. We hypothesize that this large difference in interaction volume originates from partial desolvation of the charge of DAPPH+ when it is bound to DNA.
Shi
Xuesong
X
Macgregor
Robert B
RB
D004247:DNA / Q000737:chemistry*; D004996:Ethidium / Q000031:analogs & derivatives* / Q000737:chemistry; D007364:Intercalating Agents / Q000737:chemistry*; D009690:Nucleic Acid Conformation; D055672:Static Electricity; D013816:Thermodynamics
D007364:Intercalating Agents; C029154:3,8-diamino-6-phenyl-phenanthridine; D004247:DNA; C427203:calf thymus DNA; D004996:Ethidium