Mineral Surfaces: Origin and archive of biological information – Surf_MEMO

Mineral Surfaces: Origin and archive of biological information (SURF_MEMO)
Wider research context
It has been suggested that mineral SURFaces can catalyze the oligomerization of nucleotides and play a key role in the origin of life. Moreover, new developments in evolutionary anthropology impressively demonstrate that the human and pathogen DNA can be preserved in mineral assemblages over hundreds of thousands of years, providing a biological MEMOry of the co-evolution of humans and their pathogens. However, a clear understanding of the underlying surface chemical processes is still lacking.
Objectives
SURF_MEMO tests the core hypothesis that the oligomerization of nucleotides and the preservation of ancient DNA over long timescales are governed by some of the same surface chemical mechanisms. In this context we will study a) the adsorption of mononucleotides, DNA and RNA on minerals such as hydroxyapatite and imogolite; b) the oligomerization process at mineral surfaces and its effect on the ternary secondary and ternary structure of oligonucleotides; c) the stability of the oligonucleotides, DNA and RNA on the surface and the protection from degradation processes; and d) the effect of organic surface layers on such processes.
Level of originality
The endeavour to understand the oligomerization of oligonucleotides (origin of life) and the preservation of DNA/RNA over long timescales (evolutionary anthropology) based on some of the same surface chemical molecular processes is highly innovative. More specifically our originality lies in the selection of the systems. Imogolite nanotubes are not only formed in volcanic soils (early Earth hypothesis), but their atomic structure and shape are particularly well adapted to fit with nucleic acid, RNA and DNA oligomers, in terms of phosphate groups distance and linkage to imogolite surface but also to make micrometre long assemblies. hydroxy-apatite is of paramount significance in mapping human evolution and migration history beyond a few hundred thousand years in finding potent and extractable DNA from the degraded bone materials. Our originality also lies in the possibility to custom minerals structure, shape, incorporation of trace metals, surface properties and also to custom nucleic acids from monomer to desired sequence of oligomers as well as nucleo-lipid to test the hydrophobic hypothesis. Besides a molecular scale understanding of these processes, the project may also provide practical guidelines for anthropologists regarding the extraction of ancient DNA from minerals and mineral-organic composites.
Approach
The proposed work is structured into 7 work packages. WP0 (project management) provides a seamless collaborative integration between project partners. WP1 focuses on (i) providing targeted minerals such as imogolite and apatite (synthesis and characterization) and nucleic acids with customized properties to other WPs, and (ii) conducting experiments to quantify the interaction between mineral surfaces and various nucleotides, oligomers and double stranded DNA. WP2 focuses on oligonucleotide polymerization on organic-coated and uncoated mineral surfaces. WP3 determines the role of mineral surfaces on the stabilization of secondary and ternary structure of oligonucleotides. WP4 identifies the protective effect of minerals against DNA and RNA degradation. WP5 determines the effect of organic layer properties on the protection of RNA and DNA. WP6 will disseminate our results to various audiences.
Primary researchers involved
The primary researchers are internationally recognized scientists: J. Rose (surface chemistry, CNRS, France), P. Barthelemy (organic/supramolecular chemistry, CNRS, U. of Bordeaux, France), S. Kraemer (biogeochemistry, University of Vienna, Austria). A collaboration with R. Pinhasi at the University of Vienna provides know-how in evolutionary anthropology.