Site- and sequence-selective ultrafast hydration of DNA.

ABSTRACT: Water molecules in the DNA grooves are critical for maintaining structural integrity, conformational changes, and molecular recognition. Here we report studies of site- and sequence-specific hydration dynamics, using 2-aminopurine (Ap) as the intrinsic fluorescence probe and with femtosecond resolution. The dodecamer d[CGCA(Ap)ATTTGCG]2 was investigated, and we also examined the effect of a specific minor groove-binding drug, pentamidine, on hydration dynamics. Two time scales were observed: approximately 1 ps (bulk-like) and 10-12 ps (weakly bound type), consistent with layer hydration observed in proteins and DNA. However, for denatured DNA, the cosolvent condition of 40% formamide hydration is very different: it becomes that of bulk (in the presence of formamide). Well known electron tr

SUBMITTER: Pal SK 

PROVIDER: S-EPMC283492 | biostudies-literature | 2003 Nov

REPOSITORIES: biostudies-literature