Structural analysis of anti-cancer and carcinogenic drug complexes with DNA, RNA and proteins, using capillary electrophoresis, FTIR, Raman, UV-visible and CD spectroscopic techniques as well as molecular modeling. In this regards, drug complexes such as DES (diethylstilbestrol), taxol, chlorophyllin, chlorophyll, aspirin, cisplatin, chromium-tannin, oxovanadium compounds and Cr(III), Cr(VI), Fe(II), Fe(III), AZT, cationic lipids, naturally occurring antioxidant flavonoids, carotenoids and resveratrol with calf-thymus DNA, yeast RNA, tRNA, RNase A, DNase I, Na,K-ATPase and human serum albumin have been characterized and reported by our research group Biomacromolecules ......(2007); Biochemistry and Cell Biology 85, 311-318 (2007); J. Agric. Food Chemistry 55, 970-977(2007); J. Biol. Chem. 279, 42041-42054 (2004); DNA&Cell Biology 23, 135-140 (2004); Biophys. J. 84, 2460-2466 (2003); Biochemistry 42, 11839-11845 (2003); Biophys. J. 81, 1580-1587 (2001); J. Biol. Chem. 275, 10150-10153 (2000); Biochim. Biophys. Acta 1478, 61-68, (2000), Biophys. J. 76, 2177-2182 (1999); J. Biol. Chem. 272, 8901-8904 (1997); J. Biol. Chem. 271, 8140-8143 (1996); FEBS Lett. 370, 105-108 (1995).
A part of our present research is focussed on the antioxidant activity of naturally occurring polyphenolic compounds such as flavonoids and resveratrol and their interactions with DNA, RNA and proteins. In this regard we determine the stability of the adducts formed bewteen polyphenolic compounds and nucelic acids and protein (J. Biomol. Struct. Dyn. 24, 277- 283, 2006 and Biomacromolecules, in press 2007). The results of this investigation will be useful in determination of protective roles of flavonoids aganist DNA damage that are associated with anticancer and antiviral activities of these natural products.
Other part of our investigation based on using molcular modeling in combination with other spectroscopic measurements to locate the presence of lipids (cationic and neutral lipids) in the major and minor grooves of DNA and RNA duplex. This study has direct application in gene therapy using cationic lipids as vehicles for gene delivery.
A part of our ongoing investigation is also on DNA-protein and RNA-protein interactions using capillary electrophoresis and spectroscopic methods. In this regards the strong and weak affinity bindings with nucleoic acids are located and the binding constants for different types of protein-polynucleotide complexes have been determined (DNA&Cell Biology 25, 65-68, 2006).
The structural information generated here at molecular level are used to determine the mechanism of action of biomolecular interactions and in particular the antitumor activities of drugs used in our investigations. This information can be useful in drug design and to improve the efficacy of drugs in clinical trials.