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A conformational transition in the structure of a 2'-thiomethyl-modified DNA visualized at high resolution.

ABSTRACT: Crystal structures of A-form and B-form DNA duplexes containing 2'-S-methyl-uridines reveal that the modified residues adopt a RNA-like C3'-endo pucker, illustrating that the replacement of electronegative oxygen at the 2'-carbon of RNA by sulfur does not appear to fundamentally alter the conformational preference of the sugar in the oligonucleotide context and sterics trump stereoelectronics.

SUBMITTER: Pallan PS

PROVIDER: S-EPMC2909737 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature

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A conformational transition in the structure of a 2'-thiomethyl-modified DNA visualized at high resolution.

Pallan Pradeep S PS Prakash Thazha P TP Li Feng F Eoff Robert L RL Manoharan Muthiah M Egli Martin M

Chemical communications (Cambridge, England) 20090226 15

Crystal structures of A-form and B-form DNA duplexes containing 2'-S-methyl-uridines reveal that the modified residues adopt a RNA-like C3'-endo pucker, illustrating that the replacement of electronegative oxygen at the 2'-carbon of RNA by sulfur does not appear to fundamentally alter the conformational preference of the sugar in the oligonucleotide context and sterics trump stereoelectronics. ...[more]

PMID: 19333476

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