Provisioning the origin and early evolution of life

Area of Science:

• Origin of Life Studies
• Astrobiology
• Biochemistry

Background:

• The origin of life requires access to essential biomolecules like ribonucleotides, amino acids, and lipids.
• A key debate concerns whether these building blocks were acquired pre-synthesized or synthesized by early life forms.
• The conditions and mechanisms for obtaining these precursors remain contentious in origin of life research.

Purpose of the Study:

• To evaluate the plausibility of prefabrication versus de novo synthesis for early life's building blocks.
• To investigate the environmental conditions required for the synthesis of biomolecules relevant to the origin of life.
• To challenge the hypothesis that early life synthesized its own complex organic molecules.

Main Methods:

• Review of experimental evidence regarding prebiotic synthesis pathways.
• Analysis of the feasibility of self-synthesis versus environmental acquisition of biomolecules.
• Comparative assessment of synthesis conditions required for prefabrication versus nascent biological synthesis.

Main Results:

• Experimental evidence supports the acquisition of pre-synthesized building blocks from the environment.
• Synthesis of biomolecules under life-compatible conditions, resembling extant biosynthesis, is deemed highly improbable without biological catalysts.
• The prefabrication model offers a more viable pathway for provisioning early life.

Conclusions:

• Early life likely relied on pre-existing, environmentally supplied building blocks.
• Nascent biological synthesis, especially resembling modern pathways, was likely not feasible without advanced catalytic systems.
• The origin of life may have been facilitated by environmental sources of complex organic molecules.