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Coenzymes in a pre-enzymatic metabolism
Quentin Dherbassy1, Robert J Mayer2, Joseph Moran1,3
1Institut de Science et d'Ingénierie Supramoléculaires (ISIS), CNRS UMR 7006, Université de Strasbourg - 8 Allée Gaspard Monge, 67000 Strasbourg, France.
Science Advances
|September 18, 2024
Summary
Coenzymes, essential for metabolism, catalyzed reactions before enzymes evolved. Key coenzymes like pyridoxal phosphate and adenosine diphosphate show activity without enzymes, suggesting their role in early life's origins.
Area of Science:
- Biochemistry
- Origin of Life Studies
- Metabolic Pathway Research
Background:
- Theoretical models propose coenzymes predated enzymes in catalyzing metabolic reactions.
- The Last Universal Common Ancestor (LUCA) likely relied on core metabolic processes.
- Understanding early metabolism is key to abiogenesis research.
Purpose of the Study:
- To experimentally validate the role of coenzymes in pre-enzymatic metabolism.
- To investigate the catalytic activity of essential coenzymes in the absence of enzymes.
- To provide insights into the prebiotic origins of metabolic pathways.
Main Methods:
- Conducting biochemical assays to test the activity of specific coenzymes.
- Replicating key metabolic reactions under cell-free conditions.
- Analyzing the catalytic efficiency of coenzymes without enzymatic support.
Main Results:
- Demonstrated catalytic activity of pyridoxal phosphate (PLP) in its metabolic reactions without enzymes.
- Confirmed adenosine diphosphate (ADP) and nicotinamide adenine dinucleotide (NAD) also function catalytically without enzymes.
- Experimental evidence supports coenzymes mediating core metabolic reactions prior to enzyme evolution.
Conclusions:
- Coenzymes played a crucial role in early abiogenesis and the development of metabolism.
- These findings challenge the traditional view of enzyme-centric metabolic evolution.
- Supports the hypothesis of a coenzyme-first origin of metabolic networks.
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