Nucleic acid ultraviolet spectroscopy

Optical Spectroscopy General principles and overview, 246, 13 absorption and circular dichroism spectroscopy of nucleic acid duplexes and triplexes, 246, 19 circular dichroism, 246, 34 bioinorganic spectroscopy, 246, 71 magnetic circular dichroism, 246, 110 low-temperature spectroscopy, 246, 131 rapid-scanning ultraviolet/visible spectroscopy applied in stopped-flow studies, 246, 168 transient absorption spectroscopy in the study of processes and dynamics in biology, 246, 201 hole burning spectroscopy and physics of proteins, 246, 226 ultraviolet/visible spectroelectrochemistry of redox proteins, 246, 701 diode array detection in liquid chromatography, 246, 749. 

UV and NMR studies showed that l-methyl-A -hydroxycytosine and its methyl derivatives exist predominantly in the oxo-imino form (up to 90%) (98BPC87). A review of the structure and properties of isolated nucleic acid bases with the special attention given to metal-cation-assisted tautomerization and the solvent effects has been published (99CR3247). Tautomerism of protonated cytosine has been studied experimentally by IR and Raman spectra and theoretically by ab initio and DFT calculations (96JPC5578). Neutral and protonated forms of cytidine monophosphate have been studied by ultraviolet resonance Raman spectroscopy. The amino oxo tautomer was found to be the most stable, followed by the imino oxo form. The imino-hydroxy tautomer was determined to be the least stable one. Upon protonation, the amino-oxo structure is retained (93JA760). 

Glycol nucleic acid (GNA) is a simplified DNA analogue that has an acyclic three-carbon propylene glycol phosphodiester backbone (Fig. 4) (39). Variable temperature ultraviolet (UV) spectroscopy was used to demonstrate that complementary 18-mer GNA oligomers that contain T and A bases form antiparallel, helical duplexes based on Watson-Crick base pairing, which are more stable than the analogous DNA or RNA duplexes. No NMR or X-ray structure of GNA or hybrid GNA-DNA duplexes is yet available. Both GNA and LNA oligomers can be synthesized by standard solid-phase DNA synthetic methods, because the backbone of both molecules is formed by phosphodiester bonds. 

Ultraviolet radiation, X-rays, and y-rays can all produce free radicals whose characteristics are well studied by EPR spectroscopy. Solvent water can give rise to the H- and OH- radicals which, in turn, can produce radical species in proteins and nucleic acids. In some cases the sulfur-containing amino acids give rise to S-centered radicals. 

No two instructors teach organic chemistry exactly the same way. This book covers all the fundamental topics in detail, building each new concept on those that come before. Many topics may be given more or less emphasis at the discretion of the instructor. Examples of these topics are C NMR spectroscopy, ultraviolet spectroscopy, conservation of orbital symmetiy, amino acids and proteins, nucleic acids, and the special topics chapters, lipids and synthetic polymers. 

D.C. Blazej, W.L. Peticolas, Ultraviolet resonant Raman spectroscopy of nucleic acid components. Pioc. Natl. Acad. Sci. U.S.A. 74, 2639-2643 (1977)... 

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