Spectroscopic identification of binding modes of anthracene probes and DNA sequence recognition
UNSPECIFIED. (2006) Spectroscopic identification of binding modes of anthracene probes and DNA sequence recognition. PHOTOCHEMISTRY AND PHOTOBIOLOGY, 82 (1). pp. 20-30. ISSN 0031-8655Full text not available from this repository.
Official URL: http://dx.doi.org/10.1562/2005-05-24-RA-539
The binding properties of two anthracene derivatives with calf thymus DNA (CT DNA), poly(dA-dT), and poly(dG)-poly(dC) are reported. One contained bulky, cyclic cationic substituents at the 9 and 10 positions, and the other carried acylic, branched, cationic substituents. Binding of the probes to the DNA was examined by calorimetry, spectroscopy and helix melting studies. The cyclic derivative indicated exothermic binding, strong hypochromism, bathochromism, positive induced circular dichroism (CD, 300-400 nm), significant unwinding of the helix, large increases in the helix melting temperature, strong but negative linear dichroism (LD, 300-400 nm) and considerable stabilization of the helix. In contrast, the acyclic analog indicated thermoneutral binding, smaller hypochromism, no bathochromism, very weak induced CD, and no change in the helix melting temperature with any of the DNA polymers. A sharp distinction between the binding properties of the two probes is indicated, and both have intrinsic binding constants of similar to 10(6) M-1 for the three polymers. However, when the ionic strength of the medium was lowered (10 mM NaCl), the absorption as well as CD spectral changes associated with the binding of the acyclic derivative corresponded with those of the cyclic derivative. The acyclic derivative showed large preference (10-fold) for poly(dG).oly(dC) over poly(dA-dT), whereas the cyclic analog showed no preference. The characteristic spectroscopic signatures of the two distinct binding modes of these probes will be helpful in deciphering the interaction of other anthracene derivatives with DNA.
|Item Type:||Journal Article|
|Subjects:||Q Science > QD Chemistry
Q Science > QH Natural history > QH301 Biology
|Journal or Publication Title:||PHOTOCHEMISTRY AND PHOTOBIOLOGY|
|Publisher:||AMER SOC PHOTOBIOLOGY|
|Number of Pages:||11|
|Page Range:||pp. 20-30|
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