Self-assembled prebiotic amphiphile-mixture exhibits tunable catalytic properties

Area of Science:

• Origin of life studies
• Biochemistry
• Surface chemistry

Background:

• Protocell formation relies on self-assembling amphiphiles and catalysis.
• Amino acid-based amphiphiles are potential candidates for prebiotic catalytic systems.

Purpose of the Study:

• Investigate histidine- and serine-based amphiphile formation under prebiotic conditions.
• Evaluate the catalytic activity of these self-assembled surfaces for hydrolytic reactions.

Main Methods:

• Synthesized histidine- and serine-based amphiphiles from amino acid-fatty alcohol/acid mixtures.
• Assessed catalytic activity of self-assembled surfaces for ester hydrolysis.
• Analyzed effects of chemical modifications (acylation, methylation) and co-assembled amphiphiles on catalysis.

Main Results:

• Histidine-based amphiphiles catalyzed hydrolysis with ~1000-fold rate increase.
• Catalytic efficiency was modulated by N- vs. O-acylation and N-methylation of histidine.
• Cationic serine amphiphiles enhanced catalysis, while anionic aspartic acid amphiphiles reduced it.
• Substrate selectivity observed, with hexyl esters showing higher hydrolysis rates.

Conclusions:

• Prebiotic amino acid-based surfaces act as efficient catalysts.
• Catalytic function is regulated by self-assembly, chemical modifications, and co-assembled components.
• These findings support the role of self-assembled amino acid amphiphiles in early bio-catalysis.