Dokument: The role of nitrogen in the onset of metabolism

Titel:	The role of nitrogen in the onset of metabolism
URL für Lesezeichen:	https://docserv.uni-duesseldorf.de/servlets/DocumentServlet?id=61516
URN (NBN):	urn:nbn:de:hbz:061-20230130-092125-3
Kollektion:	Dissertationen
Sprache:	Englisch
Dokumententyp:	Wissenschaftliche Abschlussarbeiten » Dissertation
Medientyp:	Text
Autor:	do Nascimento Vieira, Andrey [Autor]
Dateien:	[Dateien anzeigen] Adobe PDF [Details] 14,19 MB in einer Datei [ZIP-Datei erzeugen] Dateien vom 15.12.2022 / geändert 15.12.2022
Beitragende:	Prof. Dr. Martin, William F. [Gutachter] Preiner, Martina [Gutachter]
Dewey Dezimal-Klassifikation:	500 Naturwissenschaften und Mathematik » 570 Biowissenschaften; Biologie
Beschreibung:	Life is a set of chemical reactions that unfolded shortly after the planet's formation 4.5 billion years ago. Although direct geochemical evidence of metabolic origins is scarce, phylogenetic reconstructions of the last universal common ancestor (LUCA) shed some light on what conditions took place before and during the time of origins some 4.2 billion years ago. These reconstructions point toward aqueous, metal-bearing, serpentinizing environments such as those found in modern-day alkaline hydrothermal vents. The mechanisms of nitrogen assimilation at origins have been under intense debate for the last century due to its low geologic abundance and reactivity. Despite its relative availability, the Redfield ratio, a hypothetical formula for life, indicates the ubiquitous importance of nitrogen to cellular life. As such, a question remains. How did nitrogen get available in substantial amounts to feed early autocatalytic networks? Given the high partial pressure of dinitrogen in the atmosphere, it is plausible that this gas was the starting point to a series of reactions that would result in the formation of highly soluble and reactive nitrogen-bearing species. In this work, the mechanisms of nitrogen assimilation into prebiotically relevant organics were tested under alkaline hydrothermal conditions. The synthesis of formamide and acetamide from ammonia was attained overnight in the presence of suitable catalysts in the liquid phase, as demonstrated by 1H-NMR at 70 °C. Alanine and glycine, two proteinogenic amino acids, were also observed, but efforts to increase yields and facilitate detection are yet to be optimized. These results indicate that when given the right conditions, a simple mixture of dinitrogen (N2), carbon dioxide (CO2), ammonia (NH3), molecular hydrogen (H2), and suitable catalysts can yield the formation of organic acids and C-N-bearing molecules. These 16-hour reactions give us a glimpse of what could unfold in geologic timescales.
Lizenz:	Dieses Werk ist lizenziert unter einer Creative Commons Namensnennung 4.0 International Lizenz
Fachbereich / Einrichtung:	Mathematisch- Naturwissenschaftliche Fakultät
Dokument erstellt am:	30.01.2023
Dateien geändert am:	30.01.2023
Promotionsantrag am:	19.05.2022
Datum der Promotion:	28.10.2022