Cleaves, H.J., Scott, A.M., Hill, F.C., Leszczynski, J., Sahai, N. & Hazen, R.
Chemical Society Reviews, 41(6), pp 5502-5525.
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It remains unknown how life started on Earth. It is generally assumed that organic compounds were supplied by some environmental source (endogenous, i.e. atmospheric or geothermal, or exogenous, i.e. extraterrestrial materials such as comets, meteorites and interstellar dust particles). Regardless of the source, these compounds were probably brought together in terrestrial watery environments where mineral surfaces were present, in locations such as beaches, lagoons and submarine hydrothermal vents. These diverse mineral surfaces could have been crucial for concentrating and organizing organic materials and for catalyzing reactions which led to the origin of life.
Life is generally believed to have originated on Earth sometime between 4.4–3.5 billion years ago, via processes in which organic compounds supplied by the environment (e.g. from atmospheric or geochemical synthesis or from extraterrestrial input in the form of comets, meteorites, and interstellar dust particles) became self-organized into systems capable of replication with hereditary mutation. This process likely took place in the presence of water and mineral surfaces, for example in environmental niches such as drying beaches, small ponds, or deep in the ocean near submarine hydrothermal vents (e.g. around “black smokers”).
There are some 4400 known naturally occurring minerals, though it is likely that many of the ones present on the modern Earth were not common in the early environment, and others which are uncommon today were rather more so then. Each mineral type presents a different chemical environment, which can have a markedly different affinity for various organic compounds, depending on their type. The behavior of organic compounds on minerals surfaces is also governed by various environmental factors, such as temperature, pH, salinity, the presence of various dissolved salts, etc. Given the combination of a likely very heterogeneous organic chemical mixture and a plethora of mineral types, there are many thousands of potential interactions worth exploring with respect to the self-organization of organic matter into living systems.
Mineral surfaces thus present rich opportunities for heterogeneous catalysis and concentration which may have significantly altered and directed the process of prebiotic organic complexification leading to life. In this paper. we review general concepts in prebiotic mineral-organic interfacial processes, as well as recent advances in the study of mineral surface-organic interactions of potential relevance to understanding the origin of life. These include experimental and computational approaches, which are likely to be complementary.