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Context. Homochirality is a generic and unique property of life on Earth and is considered a universal and agnostic biosignature. Homochirality induces fractional circular polarization in the incident light that it reflects. Because this…

Homochirality is a generic and unique property of all biochemical life and the fractional circular polarization of light it induces therefore constitutes a potentially unambiguous biosignature.} However, while high-quality circular…

The identification of a universal biosignature that could be sensed remotely is critical to the prospects for success in the search for life elsewhere in the universe. A candidate universal biosignature is homochirality, which is likely to…

Biological molecules are characterized by an intrinsic asymmetry known as homochirality. The result is optical activity of biological materials and circular polarization in the light scattered by microorganisms, cells of living organisms,…

地球与行星天体物理 · 物理学 2014-06-13 Lev Nagdimunov , Ludmilla Kolokolova , Daniel Mackowski

We describe circular polarization as a remote sensing diagnostic of chiral signatures which may be applied to Mars. The remarkable phenomenon of homochirality provides a unique biosignature which can be amenable to remote sensing through…

地球与行星天体物理 · 物理学 2015-06-11 William Sparks , James H. Hough , Thomas A. Germer , Frank Robb , Ludmilla Kolokolova

Photosynthesis is an ancient metabolic process that began on the early Earth, offering plentiful energy to organisms that utilize it, to the extent that they can achieve global significance. The potential exists for similar processes to…

Circular polarization spectroscopy has proven to be an indispensable tool in photosynthesis research and (bio)-molecular research in general. Oxygenic photosystems typically display an asymmetric Cotton effect around the chlorophyll…

Photosynthetic eukaryotes show a remarkable variability in photosynthesis, including large differences in light harvesting proteins and pigment composition. In vivo circular spectropolarimetry enables us to probe the molecular architecture…

生物大分子 · 定量生物学 2018-08-27 C. H. Lucas Patty , Freek Ariese , Wybren Jan Buma , Inge Loes ten Kate , Rob J. M. van Spanning , Frans Snik

(abridged) We review recent studies of chirality using circularly polarized light, along with the birth and evolution of life and planetary systems. Terrestrial life consists almost exclusively of one enantiomer, left-handed amino acids.…

星系天体物理 · 物理学 2011-12-08 Tsubasa Fukue

Does life exist outside our Solar System? A first step towards searching for life outside our Solar System is detecting life on Earth by using remote sensing applications. One powerful and unambiguous biosignature is the circular…

Most biomolecules occur in mirror, or chiral, images of each other. However, life is homochiral: proteins contain almost exclusively levorotatory (L) amino acids, while only dextrorotatory (R) sugars appear in RNA and DNA. The mechanism…

天体物理学 · 物理学 2009-06-23 Marcelo Gleiser , Joel Thorarinson , Sara Imari Walker

Most amino acids and sugars molecules occur in mirror, or chiral, images of each other, knowns as enantiomers. However, life on Earth is mostly homochiral: proteins contain almost exclusively L-amino acids, while only D-sugars appear in RNA…

地球与行星天体物理 · 物理学 2022-12-29 Marcelo Gleiser

The homochirality of biological molecules on the Earth is a long-standing mystery regarding the origin of life. Circularly polarized ultraviolet (UV) light could induce the enantiomeric excess of biological molecules in the interstellar…

星系天体物理 · 物理学 2023-06-28 Hajime Fukushima , Hidenobu Yajima , Masayuki Umemura

Our Earth, being the only living planet that we know, provides us with clues that photosynthetic life-forms may be dominant on other exoplanets for billions of years. Spectropolarimetric signatures of the terrestrial photosynthetic life…

Spectropolarimetry of intact plant leaves allows to probe the molecular architecture of vegetation photosynthesis in a non-invasive and non-destructive way and, as such, can offer a wealth of physiological information. In addition to the…

A key open question in the study of life is the origin of biomolecular homochirality: almost every life-form on Earth has exclusively levorotary amino acids and dextrorotary sugars. Will the same handedness be preferred if life is found…

生物大分子 · 定量生物学 2015-06-04 Marcelo Gleiser , Sara Imari Walker

We present a comprehensive set of spectropolarimetric observations of Earthshine as obtained by FORS2 at the VLT for phase angles from 50degree to 135degree (Sun-Earth-Moon angle), covering a spectral range from 430nm to 920nm. The degree…

地球与行星天体物理 · 物理学 2019-01-30 Michael F. Sterzik , Stefano Bagnulo , Daphne M. Stam , Claudia Emde , Mihail Manev

Many biologically produced chiral molecules such as amino acids and sugars show a preference for left or right handedness (homochirality). Light reflected by biological materials such as algae and leaves therefore exhibits a small amount of…

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…

生物物理 · 物理学 2021-10-06 Noemie Globus , Roger D. Blandford , Anatoli Fedynitch

The search for life elsewhere in the universe is a pivotal question in modern science. However, to address whether life is common in the universe we must first understand the likelihood of abiogenesis by studying the origin of life on…

天体物理学 · 物理学 2008-11-11 Marcelo Gleiser , Sara Imari Walker
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