title: Absolute configurations of DNA lesions determined by comparisons of experimental ECD and ORD spectra with DFT calculations.
abstract: The usefulness of modern density functional theory (DFT) methods is considered for establishing the absolute configurations of DNA lesions by comparisons of computed and experimentally measured optical rotatory dispersion (ORD) and electronic circular dichroism (ECD) spectra. Two rigid, structurally different DNA lesions (two spiroiminodihydantoin stereoisomers and four equine estrogen 4-hydoxyequilenin-DNA stereoisomeric adducts) have been investigated. In all cases, the signs and shapes of the computed ORD spectra reproduced the experimentally measured ORD spectra, although the magnitudes of the computed and experimental ORD values do not coincide exactly. The computed ECD spectra also reproduced the shapes of the experimental ECD spectra rather well, but are blue-shifted by 10-20 nm. Since the assignments of the absolute configurations of the DNA lesions studied based on computed and experimental ORD and ECD spectra are fully consistent with one another, the computational DFT method shows significant promise for determining the absolute configurations of DNA lesions. Establishing the stereochemistry of DNA lesions is highly useful for understanding their biological impact, especially when sufficient amounts of material are not available for other methods of structural characterization.
authors: Department of Biology, New York University, New York, USA.
authors: Shuang
authors: S
authors: Ding
authors: Alexander
authors: A
authors: Kolbanovskiy
authors: Alexander
authors: A
authors: Durandin
authors: Conor
authors: C
authors: Crean
authors: Vladimir
authors: V
authors: Shafirovich
authors: Suse
authors: S
authors: Broyde
authors: Nicholas E
authors: NE
authors: Geacintov
mesh_terms: D002942:Circular Dichroism / Q000295:instrumentation / Q000379:methods*; D004247:DNA / Q000737:chemistry*; D018736:DNA Adducts / Q000737:chemistry*; D004581:Electronics; D008968:Molecular Conformation; D015394:Molecular Structure; D009690:Nucleic Acid Conformation; D009905:Optical Rotatory Dispersion; D013056:Spectrophotometry, Ultraviolet; D013237:Stereoisomerism
chemical_list: D018736:DNA Adducts; D004247:DNA