In silico investigations towards homochirality in the context of the origin of life

Huber, Laura (2023): In silico investigations towards homochirality in the context of the origin of life: symmetry breaking by consecutive amplification & atmospheric modelling of a reaction network in a prebiotic context & system validation for a soai autocatalysis. Dissertation, LMU München: Fakultät für Chemie und Pharmazie

Abstract

The future of the improvements of industrial and chemical processes is likely to be data-based. An elementary implementation for this are continuously developed tools to gain in-sights into complex reaction networks. This work provides insights into the design and ap-plication of two reaction kinetic tools and exhibits the broad application potential thereof ranging from autocatalysis to prebiotic reaction networks. The first context in which the developed program for reaction network analysis was applied to, was an Origin of Life project. Since the approaches to fathom the origin of homochirality are diverse, explicit model development is crucial. In this dissertation, a cheminformatics approach was chosen for the first topic (chapter 3) to observe symmetry breaking at the molecular level. This is particularly interesting because the tool SMK.exe we developed, can be adapted for a multitude of different chemical reaction networks. First, an insight into the program structure and functionality was given. Input and output requirements were discussed as well as the validation of reproducibility. Then, this efficient method for studying the reaction kinetics of single molecules was applied to several model systems including both autocatalysis systems and a cascade reaction. Important implica-tions for the combination of kinetic requirements towards symmetry breaking on a molecular level by statistical sampling were obtained. By means of a statistical analysis and a long-term simulation, it could be confirmed that the system has not exhibit any bias and that the formation of a preferred enantiomer is random. In the second subject area (chapter 4) the primordial atmosphere of a planet was examined with a further developed cheminformatics tool (RNA.exe). Based on experimental findings, a robust atmospheric model was developed. With this model, a large-scale in silico catalysis was carried out in which important organic molecules were formed from atmospheric gases. A novel marker within the system for CO2 fixation, building block formation and thus the Origin of Life was identified. The crucial role of H2 formation and consumption was demon-strated. The general significance of whether any early Earth-like metallosilicate planet would be able to provide evidence of the emergence of life was discussed. The third subject area was the validation of the advanced RNA.exe tool (chapter 5) in an autocatalytic setting. The program was validated using experimental kinetic data on the SOAI reaction. The refinement method and the accuracy of the simulated sets were shown.

• Dokumententyp: Dissertationen (Dissertation, LMU München)
• Keywords: Chiral Symmetry Breaking, Prebiotic Complexity, Origin of Homochirality, Origin of Life, Soai Autocatalysis, Single Molecule Reaction Kinetics
• Themengebiete: 500 Naturwissenschaften und Mathematik ; 500 Naturwissenschaften und Mathematik > 540 Chemie
• Fakultäten: Fakultät für Chemie und Pharmazie
• Sprache der Hochschulschrift: Englisch
• Datum der mündlichen Prüfung: 14. Juli 2023
• 1. Bericht­erstatter:in: Trapp, Oliver