2plb

Publication Abstract from PubMed

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.

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^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.