Molecular spectroscopy assignment

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KIM 4106 SEM 1 18/19 ASSIGNMENT

QUANTUM ORIGIN OF LIFE

NAME : SARMILLA SREE A/P MUNIANDY (S43906) PROGRAMME : BACHELOR OF SCIENCE (CHEMICAL SCIENCES) LECTURER’S NAME: PROF DR KU HALIM BIN KU BULAT

Quantum Origin of Life Some defines life as an illusion and some defines as the living matter and, as such, matter that shows certain attributes that include responsiveness, growth, metabolism, energy transformation and reproduction. Although there is no agreement in definition of life, Davies said that all living things are information processors whereby they store a genetic database and replicate it, with occasional errors, thus providing the basis for natural selection. The great scientist, Schrödinger also argued that the stable transmission of genetic information from generation to generation in discrete bits implied a quantum mechanical process, although he was unaware of the role of or the specifics of genetic encoding in 1944. Biological molecules do not only specialized in chemical role but they are also specialized in informational role. In recent years our understanding of the nature of information has undergone something of a revolution with the development of the subjects of quantum computation and quantum information processing. The starting point of this enterprise is the replacement of the classical “bit” by its quantum counterpart, the “qubit”. As a quantum system evolves, information is processed, stated by Davies, 2003. In the case of familiar DNA based life, the information represented by the base-pair sequence such as adenine, guanine, tyrosine and cytosine are replicated together. Thus information replication is tied to structural replication. But at the quantum level there are alternative possibilities. Consider, for example, a cellular automaton, such as the Game of Life. One of the great question of biology is, to synthesise these informative molecules, all we need is only 13 amino acids. Then why the genetic basis in life involves 20 amino acids? An international team of researchers has created a quantum chemistry models that explains what triggered the inclusion of the additional 7 amino acids in 2018. A spike in the levels of oxygen in our biosphere, coupled with the discovery that the newer amino acids have a greater chemical reactivity than the older ones. Moosmann and his colleagues created a quantum chemistry model that compared amino acids on Earth to amino acids from space that had arrived via meteorites. There's less to react to out in space than there is on Earth, so while in space the handful of older amino might suffice, life inside our atmosphere required a little extra help. The researchers found that the younger the amino, the more reactive it is to external forces, making it more adaptable—an advantage in pretty much anything involving the evolutionary process. The researchers conducted additional experiments which verified their theoretical results. They found that at least three of the newer amino such as methionine, tryptophan and selenocysteine that were included in response to the rising levels of oxygen in our atmosphere. We find that the energetic HOMO–LUMO gap, a correlate of chemical reactivity, becomes incrementally closer in modern amino acids, reaching the level of specialized redox cofactors in the late amino acids tryptophan and selenocysteine due to evolutionary position in the genetic code. (Granold

et al.,

2018). This results in primordial life to deploy increasingly soft molecules such as in mammals and fungi.

References Davies, P. C. W. (1953). A Quantum Origin of Life ? https://doi.org/10.1142/9781848162556_0001

Molecular Biology

, 3–18. Granold, M., Hajieva, P., Toşa, M. I., Irimie, F.-D., & Moosmann, B. (2017). Modern diversification of the amino acid repertoire driven by oxygen.

Proceedings of the National Academy of Sciences

,

115

(1), 201717100. https://doi.org/10.1073/pnas.1717100115

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