Biology, Consciousness and the Double Helix
The Biology of the Double Helix
Why Does DNA have a Double Helix Structure
An important property of nucleic acids is 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.
The discovery of ribozymes and then the demonstration that ribosomal peptide synthesis is a ribozyme-catalysed reaction strengthened the case for an early RNA World. In this context, the central problem for origin-of-life studies is to understand how this seminal world became established on the primitive Earth. Plausible scenarios for the prebiotic chemistry have been proposed, but the problem is far from being solved. A recurrent theme is that RNA may have emerged from an earlier world under extreme conditions of pressure and/or temperature and pH. In all scenarios, molecules with backbones forming stable double helices held together by Watson–Crick base pairing appear as crucial intermediates or crucial building blocks. This fact led to a programme to examine the behaviour of such molecules under high pressure.
Crystals of the nucleotide were compressed up to 2 GPa at 295 K. The geometry of Watson–Crick base pairings remains essentially invariant in the pressure domain up to 1.39 GPa. These results highlight the remarkable adaptation of the base-paired double-helix architecture to high pressure.
The Watson–Crick type of base-pair association, which represents the foundation of the genetic code transmission, could be another way for the helix to ‘breathe’ transversally.
The remarkable adaptation of d(GGTATACC) to high pressure is clearly associated to the base-paired double-helix topology of the molecule, by which it behaves as a molecular spring. These properties are probably shared by molecules featuring similar topology, with sugar-phosphate or polypeptide backbones. At the prebiotic stage, the base-paired double-helix architecture was crucial in the emergence of molecules with catalytic properties and able to store genetic information. Such architectures could withstand not only pressure in the deepest sea trenches but also much higher pressures found in Earth's interior or in the context of rare events such as impact of a meteorite. We suggest that this remarkable adaptation to harsh conditions may have played an important role during the sequence of events that led to the seminal RNA World.
Adaptation of the base-paired double-helix molecular architecture to extreme pressure Oxford Journal – Nucleic Acids Research-Eric Girard, Thierry Prangé et al 2002
Sunlight and DNA – Marek Lassota
Life did not emerge through chemistry or physics alone, but a combination of sunlight and quantum mechanics, said Marek Lassota, a 57-year-old Polish-born engineer.
The theory is laid out in Lassota's book, "Life Decoded: The Sun, Your Origin and the Creation of Life in the Universe” The basis of his code theory lies in the wave-like nature of light. The peaks and valleys of light waves can be charted with a machine that breaks light into its constituent colours, ranging from the infra-red through the visible spectrum (red, yellow, green, etc.) to the ultraviolet (spectrograph). The colour bands are crossed by dark lines known as Fraunhofer Lines, named for the German scientist Joseph von Fraunhofer, who discovered them in 1814.Each line indicates the presence of a specific chemical element (which is how astronomers are able to determine the chemical composition of the sun and other stars).
But what's the connection between Fraunhofer Lines and RNA/DNA? First, they represent similar organizations of a huge amount of data. Second, put the lines and DNA patterns side by side, and they both look alike.
Lassota said "These are the only two instances in nature where massive amounts of information are organized in the same way. It's just star spectrum and life"………
“Information from sunlight transfers to RNA/DNA through photosynthesis, but chemistry can't do it alone. Physics and quantum mechanics appear to play critical roles, too. For the first time, a direct link has been made between physics and the origin of life."
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