Low-Temperature conformation of Mg2+-Poly(U) in D2O as revealed by IR and Raman Spectroscopy and by normal-mode analysis treatment

✍ Scribed by Jagdeesh Bandekar; Georg Zundel

• Publisher: Wiley (John Wiley & Sons)
• Year: 2007
• Tongue: English
• Weight: 878 KB
• Volume: 23
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.360231132

✦ Synopsis

Infrared and Raman spectra of the Mgz+ salt of poly(U) in DzO were recorded in the 16W1800 cm-' region and between 1 and 20°C. The ir spectra showed a melting curve similar to the uv melting curves with a temperature of transition of about 6.5"C. This spectral change is assumed to be associated with the formation of the secondary structure of Mg2+-poly(U) in D20 at this temperature. Three double-helical and two triple-helical structures were used as inputs to compute the normal modes of vibration. A doublehelical structure was found to give the best agreement with the observations. Knowledge of the C=O eigenvectors, and of the expression for transition probability from quantum mechanics, was used to explain the so far unanswered question of H.