화학공학소재연구정보센터
Journal of the American Chemical Society, Vol.130, No.28, 9072-9079, 2008
Backbone dynamics in the DNA Hhal protein binding site
The dynamics of the phosphodiester backbone in the [5'-GCGC-3'](2) moiety of the DNA oligomer [d(G(1)A(2)T(3)A(4)G(5)C(6)G(7)C(8)T(9)A(10)T(11)C(12))](2) are studied using deuterium solid-state NMR (SSNMR). SSNMR spectra obtained from DNAs nonstereospecifically cleuterated on the 5' methylene group of nucleotides within the [5'-GCGC-3'](2) moiety indicated that all of these positions are structurally flexible. Previous work has shown that methylation reduces the amplitude of motion in the phosphodiester backbone and furanose ring of the same DNA, and our observations indicate that methylation perturbs backbone dynamics through not only a loss of mobility but also a change of direction of motion. These NMR data indicate that the [5'-GCGC-3'](2) moiety is dynamic, with the largest amplitude motions occurring nearest the methylation site. The change of orientation of this moiety in DNA upon methylation may make the molecule less amenable to binding to the Hhal endonuclease.