Effects of the stripping solution concentrations on the separation degree in Donnan dialysis for binary systems of amino acids

Recent work has produced theoretical evidence for two sites, colliding neutron stars and neutron-star–Wolf–Rayet binary systems, which might produce amino acids with the left-handed chirality preference found in meteorites. The Supernova Neutrino Amino Acid Processing (SNAAP) model uses electron antineutrinos and the magnetic field from source objects such as neutron stars to preferentially destroy one enantiomer over another. Large enantiomeric excesses are predicted for isovaline and alanine; although based on an earlier study, similar results are expected for the others. Isotopic abundances of 13 C and 15 O in meteorites provide a new test of the SNAAP model. This presents implications for the origins of life.

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Heteromolecular compounds in binary systems of amino acids with opposite and same chiralities

CrystEngComm ◽

10.1039/c9ce01333d ◽

2020 ◽

Vol 22 (5) ◽

pp. 986-997 ◽

Cited By ~ 1

Author(s):

Anton I. Isakov ◽

Heike Lorenz ◽

Andrey A. Zolotarev ◽

Elena N. Kotelnikova

Keyword(s):

Amino Acids ◽

Binary Systems ◽

Side Chain

Equimolar and non-equimolar heterocompounds of amino acids are examined with a common approach considering their molecular dimers, side chain structures and conformations.

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Some Results of the Spectroscopic Study of Four Close Binary Systems of Early Spectral Types

International Astronomical Union Colloquium ◽

10.1017/s025292110002755x ◽

1965 ◽

Vol 5 ◽

pp. 120-130

Author(s):

T. S. Galkina

Keyword(s):

Spectroscopic Study ◽

Spectral Type ◽

Spectroscopic Investigation ◽

Binary Systems ◽

Quantitative Information ◽

Close Binary ◽

Physical Parameters ◽

Absorption And Emission ◽

Close Binary Systems ◽

Quantitative Estimates

It is necessary to have quantitative estimates of the intensity of lines (both absorption and emission) to obtain the physical parameters of the atmosphere of components.Some years ago at the Crimean observatory we began the spectroscopic investigation of close binary systems of the early spectral type with components WR, Of, O, B to try and obtain more quantitative information from the study of the spectra of the components.

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Homochirality as the Signature of Extra-Terrestrial Life

International Astronomical Union Colloquium ◽

10.1017/s0252921100015037 ◽

1997 ◽

Vol 161 ◽

pp. 505-510

Author(s):

Alexandra J. MacDermott ◽

Laurence D. Barron ◽

Andrè Brack ◽

Thomas Buhse ◽

John R. Cronin ◽

...

Keyword(s):

Amino Acids ◽

Protein Synthesis ◽

Optical Rotation ◽

Physical Origin ◽

Natural Choice ◽

Rosetta Mission ◽

Terrestrial Life ◽

Subsurface Layers ◽

Solar System Bodies ◽

Origin Of Homochirality

AbstractThe most characteristic hallmark of life is its homochirality: all biomolecules are usually of one hand, e.g. on Earth life uses only L-amino acids for protein synthesis and not their D mirror images. We therefore suggest that a search for extra-terrestrial life can be approached as a Search for Extra- Terrestrial Homochirality (SETH). The natural choice for a SETH instrument is optical rotation, and we describe a novel miniaturized space polarimeter, called the SETH Cigar, which could be used to detect optical rotation as the homochiral signature of life on other planets. Moving parts are avoided by replacing the normal rotating polarizer by multiple fixed polarizers at different angles as in the eye of the bee. We believe that homochirality may be found in the subsurface layers on Mars as a relic of extinct life, and on other solar system bodies as a sign of advanced pre-biotic chemistry. We discuss the chiral GC-MS planned for the Roland lander of the Rosetta mission to a comet and conclude with theories of the physical origin of homochirality.

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