Amino Acid Asymmetry – AAAs

A special gas cell will be developed that will allow us to generate CD and anisotropy data. The gas cell, with a 500 mm optical path length, will operate in the range from the vacuum ultraviolet to the visible. The gas cell will be pressure-controlled and can be heated up to 200 °C to allow for a sufficient amino acid gas phase density. CD and anisotropy spectra of amino acids will be systematically studied in the gas phase at the Danish synchrotron facility ASTRID2.

We have developed a gas cell that is temperature and pressure controlled. The cell is mounted on the AU-CD beam line, where CD measurements were performed

The results obtained on the origin of the chiral molecular building blocks of life, i.e., amino acids and ribose sugars, will be interpreted using our data from both the ongoing cometary Rosetta-Philae mission and the scheduled ExoMars mission. AAAs coordinator Meierhenrich is co-investigator in both missions (COSAC and MOMA). Through the combination of laboratory with space data (comet and Mars), the AAAs project aims to decipher the asymmetric origin of life on Earth.

Garcia A.D., Meinert C., Sugahara H., Jones N.C., Hoffmann S.V., Meierhenrich U.J.: The Astrophysical Formation of Asymmetric Molecules and the Emergence of a Chiral Bias. Life 9 (2019), 1-21.
www.mdpi.com/2075-1729/9/1/29

Leseigneur G., Garcia A.D., Meinert C., Le Sergeant d'Hendecourt L., Meierhenrich U.J.: Rosetta and ExoMars sur les traces des origines moléculaires de la vie.L'Actualité Chimique 455 (2020), 17-23.
www.lactualitechimique.org/Rosetta-et-ExoMars-sur-les-traces-des-origines-moleculaires-de-la-vie

Pepino R.L., Garcia A.D., Bockova J., Garcia A., Danger G., Meierhenrich U.J., Meinert C.: Les innombrables applications de la chromatographie bidimensionnelle en phase gazeuse. L’Actualité Chimique (2021) in print

Meinert C., Garcia A.D., Meierhenrich U.J., Nahon L., Kaiser R.I., Jones N.C., Hoffmann S.V., d’Hendecourt L.: Photochemical synthesis, chirality and detection of the building blocks of life in ‘simulated’ cometary matter (invited). Astrobiology Science Conference, Seattle, Washington, US, 24–28 June 2019.

Nahon L.: VUV circularly-polarized light in interaction with chiral matter: possible implications for the origin of life’s homochirality (Invited lecture). Bioscience Department of LALN, Los Alamos, USA, 14 November 2019.

Meierhenrich U.J.: Comet and Interstellar Ice and the Molecular Origins of Life. PETRA IV online Workshop (invited). Hamburg, Germany, 2 – 4 November 2020.

Meierhenrich U.J.: 3D Presentation Rosetta Philae – The Detection of Organic Molecules on the Surface of a Cometary Nucleus (invited talk, online conference). GDCh 27th Lecture Conference on Photochemistry, Kiel, Germany 14–15 September 2020.

Meierhenrich U.J.: 3D Presentation Rosetta-Philae – The Detection of Organic Molecules on the Surface of a Cometary Nucleus (invited talk, online conference), Molecular Origins of Life, Munich, Germany, 8–10 July 2020.

Proteins and nucleic acids are functional biopolymers composed of L-amino acids and D ribose subunits that break chiral symmetry. The origin of the symmetry-breaking event is unknown. The photochemistry model by which circularly polarized light (cpl) can induce an enantiomeric excess (e.e.) in organic molecules has recently been strengthened by the observation of cpl in the star-forming region of Orion and the detection of photochemically produced organics in cometary ices by the Rosetta-Philae mission. The ‘Amino Acid Asymmetry’ (AAAs) project proposes to characterize chiroptical properties of chiral amino acids and their volatile aldehyde precursor molecules for the first time in the gas phase, where the initial asymmetric interactions between chiral photons and life’s molecular subunit precursors are assumed to occur. Gas phase circular dichroism (CD) and anisotropy spectra of amino acids have never been recorded.

A special gas cell will be developed that will allow us to generate CD and anisotropy data. The gas cell, with a 500 mm optical path length, will operate in the range from the vacuum ultraviolet to the visible. The gas cell will be pressure-controlled and can be heated up to 200 °C to allow for a sufficient amino acid gas phase density. CD and anisotropy spectra of amino acids will be systematically studied in the gas phase at the Danish synchrotron facility ASTRID2.

After recording the amino acid chiroptical data, we will expose amino acids in the gas phase to circularly polarized synchrotron radiation at the DESIRS beamline of the synchrotron SOLEIL in France. The asymmetry of the chiral photons will be transferred to racemic amino acids in the gas phase. After condensation of the gas-phase irradiated amino acids, the samples will be analyzed for the determination of the induced enantiomeric excess. These analyses will be performed by using enantioselective multidimensional gas chromatography at the University Nice Sophia Antipolis. Furthermore, we will simulate the photochemical and low-temperature/low-pressure interstellar formation of pristine organic molecules: Amino acids will be photo-chemically formed from C1 and N1 reactants such as methanol, ammonia, and water by using circularly polarized synchrotron radiation at the DESIRS beamline, SOLEIL. Reactants will be 13C-labeled to distinguish the photochemical products from contaminants. The AAAs project will investigate and characterize the asymmetry transfer from chiral photons to pristine chiral organic species. Data will be employed to decipher the asymmetric origin of functional biopolymers.

The results obtained on the origin of the chiral molecular building blocks of life, i.e., amino acids and ribose sugars, will be interpreted using our data from both the ongoing cometary Rosetta-Philae mission and the scheduled ExoMars mission. AAAs coordinator Meierhenrich is co-investigator in both missions (COSAC and MOMA). Through the combination of laboratory with space data (comet and Mars), the AAAs project aims to decipher the asymmetric origin of life on Earth.