Astrochemistry

Polarized Muons And The Origin Of Biological Homochirality

By Keith Cowing

physics.bio-ph

October 5, 2021

Filed under astrochemistry

Polarized Muons And The Origin Of Biological Homochirality — The figure shows the 3D structure of the DNA molecule and protein, and their mirror images. The direction of the helical conformation of the nucleic acids derives from the underlying chemical chirality of the sugar backbone. The nucleic acids contain only right-handed sugars (D-ribose in RNA, D-deoxyribose in DNA), shown in the right-hand side of the figure. They naturally assume a right-handed helical conformation. In the mirror world (left-hand side in the figure), the nucleic acids would contain only left-handed sugars (L-ribose or L-deoxyribose) and would assume a predominantly left-handed helical conformation. Note that "left-handed" and "right-handed" are only human conventions.

While biologists have not yet reached a consensus on the definition of life, homochirality – the specific molecular handedness of biomolecules – is a phenomenon only produced by life.

The unraveling of its origin requires interdisciplinary research, by exploring fundamental physics, chemistry, astrophysics and biology. Here, we consider the origin of biological homochirality in the context of astrophysics and particle physics. The weak force, one of the fundamental forces operating in nature, is parity-violating.

On Earth, at ground level, most of our cosmic radiation dose comes from polarized muons formed in a decay involving the weak force. We discuss how the magnetic polarization is transmitted in cosmic showers within several different environments which are prime targets in the search for the origin of life. We consider how this polarization could have induced a biological preference for one type of chirality over the other, and discuss the implications for the search of life in other worlds.

Noemie Globus, Roger D. Blandford, Anatoli Fedynitch

Comments: Proceedings of the ICRC 2021 PoS(ICRC2021)031
Subjects: Biological Physics (physics.bio-ph); Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2110.01975 [physics.bio-ph] (or arXiv:2110.01975v1 [physics.bio-ph] for this version)
Submission history
From: Noemie Globus
[v1] Thu, 16 Sep 2021 23:52:41 UTC (4,865 KB)
https://arxiv.org/abs/2110.01975
Astrobiology, Astrochemistry

Keith Cowing

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻

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