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2pkv
From Proteopedia
D-(GGTATACC) ambient pressure
Overview
The behaviour of the d(GGTATACC) oligonucleotide has been investigated by X-ray crystallography at 295 K in the range from ambient pressure to 2 GPa (approximately 20,000 atm). Four 3D-structures of the A-DNA form (at ambient pressure, 0.55, 1.09 and 1.39 GPa) were refined at 1.60 or 1.65 A resolution. In addition to the diffraction pattern of the A-form, the broad meridional streaks previously explained by occluded B-DNA octamers within the channels of the crystalline A-form matrix were observed up to at least 2 GPa. This work highlights an important property of nucleic acids, their capability to withstand very high pressures, while keeping in such conditions a nearly invariant geometry of base pairs that store and carry genetic information. The double-helix base-paired architecture behaves as a molecular spring, which makes it especially adapted to very harsh conditions. These features may have contributed to the emergence of a RNA World at prebiotic stage.
About this Structure
Full crystallographic information is available from OCA.
Reference
Adaptation of the base-paired double-helix molecular architecture to extreme pressure., Girard E, Prange T, Dhaussy AC, Migianu-Griffoni E, Lecouvey M, Chervin JC, Mezouar M, Kahn R, Fourme R, Nucleic Acids Res. 2007;35(14):4800-8. Epub 2007 Jul 7. PMID:17617642 Page seeded by OCA on Sun May 4 13:19:18 2008
