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Abstract

Oligomers of the negatively-charged amino acids, glutamic acid, aspartic acid, and O-phospho-L-serine are adsorbed by hydroxylapatite and illite with affinities that increase with oligomer length. In the case of oligo-glutamic acids adsorbed on hydroxylapatite, addition of an extra residue results in an approximately four-fold increase in the strength of adsorption. Oligomers much longer than the 7-mer are retained tenaciously by the mineral. Repeated incubation of short oligo-glutamic acids adsorbed on hydroxylapatite or illite with activated monomer leads to the accumulation of oligomers at least 45 units long. The corresponding reactions of aspartic acid and O-phospho-L-serine on hydroxylapatite are less effective in generating long oligomers, while illite fails to accumulate substantial amounts of long oligomers of aspartic acid or of O-phospho-L-serine.

The origin and emergence of life under impact bombardment

“…In many hydrothermal systems, such as those of Popigai crater, Russia; Carswell crater, Canada and Manson crater, USA, illite is to be found in the lithic breccias and melt rocks (suevite; Naumov 2005). Illite can act as a template for the synthesis of polypeptides (Hill et al 1998;Liu & Orgel 1998;Orgel 1998). Ferris et al (1996) synthesized polypeptides with over 55 monomers on illite clays.…”

Polyesters as a Model System for Building Primitive Biologies from Non-Biological Prebiotic Chemistry

“…In biochemistry, peptides are synthesized from amino acids through a complex system of enzyme-mediated, energy-consuming reactions. Abiotic peptide synthesis is often accomplished with varying degrees of success through activation (e.g., [47][48][49][50]), heating, and/or low water activity conditions (e.g., [51][52][53]). Alternatively, polyesters, which have a considerably lower energy for bond formation (~0 kcal mol −1 [54]), have been considered as possible ancestral precursors of peptides [36,55].…”

Mineral Surface-Templated Self-Assembling Systems: Case Studies from Nanoscience and Surface Science towards Origins of Life Research

“…Although these examples are all of modern peptide self-assemblies in applicational settings, peptide self-assemblies, including those templated by mineral surfaces, are still relevant to prebiotic chemistry as they are structures that can provide structural and functional complexity to early living systems. Although amino acids produced on early Earth through atmospheric discharge [ 101 , 102 ], from extraterrestrial sources including meteorites [ 103 ] and in undersea hydrothermal systems [ 104 , 105 ] can then polymerize into simple peptides through volcanic-gas activation of amino acid monomers [ 106 , 107 ] or on clay mineral surfaces coupled with wet–dry cycles [ 23 , 24 , 25 , 108 ], the ability of mineral surfaces to catalyze the polymerization of very long peptides with catalytic functions remains poorly studied and understood. Thus, self-assembly of short peptides may be one energetically favorable way for an early Earth system to access emergent architectures or functional properties.…”

“…Minerals are produced during the formation of terrestrial planets [ 9 ], and various minerals, including apatites (Ca 5 (PO 4 ) 3 (F,Cl,OH)) [ 10 ], phosphate minerals such as schreibersite ((Fe,Ni)3P) [ 11 , 12 ], and borates such as colemanite (Ca 2 B 6 O 11 ·5H 2 O) [ 13 , 14 ] (although boron is fairly common in different sedimentary rocks, a mechanism by which high concentrations of specific borate minerals could have accumulated on early Earth is unclear [ 15 ]), can catalyze the synthesis of nucleotides and amino acids from simple chemical precursors like phosphates, nucleosides, or formamide. These nucleotides and amino acids can adsorb onto clay minerals such as montmorillonite ((Na,Ca) 0.33 (Al,Mg) 2 (Si 4 O 10 )(OH) 2 ·nH 2 O), illite ((K,H 3 O)(Al,Mg,Fe) 2 (Si,Al) 4 O 10 [(OH) 2 ,(H 2 O)]), and kaolinite (Al 2 Si 2 O 5 (OH) 4 ) [ 16 , 17 , 18 ], which can catalyze their polymerization into more complex biopolymers such as nucleic acids [ 19 , 20 , 21 , 22 ] and peptides [ 23 , 24 , 25 , 26 , 27 ]. Various mineral surfaces such as montmorillonite [ 28 ], silicates (such as aluminum silicate, Al 2 SiO 5 ), carbonates (such as hydrotalcite, Mg 6 Al 2 CO 3 (OH) 16 ·4(H 2 O)) [ 29 ], and sulfides (such as pyrite, FeS 2 ), among others [ 30 ] have also been shown to promote fatty acid vesicle formation, an important process in the initial development of primitive cells by which biopolymers become stably encapsulated within a compartment, i.e., a protocell.…”