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From Proteopedia
SOLUTION STRUCTURE OF DNA SEQUENCE GGGTTCAGG FORMS GGGG TETRADE AND G(C-A) TRIAD.
Overview
We have designed a DNA sequence, d(G-G-G-T-T-C-A-G-G), which dimerizes to form a 2-fold symmetric G-quadruplex in which G(syn). G(anti).G(syn).G(anti) tetrads are sandwiched between all trans G. (C-A) triads. The NMR-based solution structural analysis was greatly aided by monitoring hydrogen bond alignments across N-H...N and N-H...O==C hydrogen bonds within the triad and tetrad, in a uniformly ((13)C,(15)N)-labeled sample of the d(G-G-G-T-T-C-A-G-G) sequence. The solution structure establishes that the guanine base-pairs with the cytosine through Watson-Crick G.C pair formation and with adenine through sheared G.A mismatch formation within the G.(C-A) triad. A model of triad DNA was constructed that contains the experimentally determined G.(C-A) triad alignment as the repeating stacked unit.
About this Structure
Full crystallographic information is available from OCA.
Reference
A two-stranded template-based approach to G.(C-A) triad formation: designing novel structural elements into an existing DNA framework., Kettani A, Basu G, Gorin A, Majumdar A, Skripkin E, Patel DJ, J Mol Biol. 2000 Aug 4;301(1):129-46. PMID:10926497 Page seeded by OCA on Fri May 2 15:51:27 2008
