121 / 2023-10-10 23:10:31

The facilitation of trimetaphosphate on the protocell self-assembly

Trimetaphosphate, Protocell, N-acyl amino acid

Phosphorus in Origin of Life and Space Science > 1) The role of phosphorus in the origin of life

    As a prebiotic cell membrane precursor, fatty acid can form the protocell membrane with good permeability, which can facilitate the entry and exit of substances, and shape change. The peptide formation and membrane self-assembly in the origin of life have some synergistic effects^[1]. Sodium trimetaphosphate (P₃m), an available phosphorus source under prebiotic conditions, can activate amino acids to form peptides, link nucleosides with amino acids to form aa-N-XMP^[2], and to phosphorylate nucleoside to obtain nucleotide. Does P₃m also have some roles during the process of protocell self-assembly?

    Recently, we systematically investigated the sodium trimetaphosphate (P₃m) activated peptide formation reaction of 12 representative amino acids in an alkaline decanoic acid-decanol vesicle system. It was found that the peptide formation could competitively occur with N-acyl amino acid (NAA) formation. As a kind of membrane-forming amphiphile, NAA can form vesicles independently, reduce the critical vesicle concentration of the fatty-acid vesicles and promote the growth of decanoic acid-decanol vesicles. It has been reported that NNAs (N- Decanoylarginine, DA-Arg) can promote membrane growth and oligonucleotide RNA localization^[3]. Besides, Phe-Leu dipeptide can also promote the growth of the membrane. Our present work indicates that synergistic symbiosis between membrane and peptide can be realized via the P₃m activation effect. Through forming NAAs and functional peptides, P₃m facilitate the protocell self-assembly. NAAs possess a chiral centre. When NAAs are embedded into the protocell membrane, they may have the ability to regulate the entry of chiral molecules into the protocell.

Keywords: Trimetaphosphate, Protocell, N-acyl amino acid