Adsorption and Polymerization of Amino Acids on Mineral Surfaces: A Review

Abstract

The present paper offers a review of recent (post-1980) work on amino acid adsorption and thermal reactivity on oxide and sulfide minerals. This review is performed in the general frame of evaluating Bernal's hypothesis of prebiotic polymerization in the adsorbed state, but written from a surface scientist's point of view. After a general discussion of the thermodynamics of the problem and exactly what effects surfaces should have to make adsorbed-state polymerization a viable scenario, we examine some practical difficulties in experimental design and their bearing on the conclusions that can be drawn from extant works, including the relevance of the various available characterization techniques. We then present the state of the art concerning the mechanisms of the interactions of amino acids with mineral surfaces, including results from prebiotic chemistry-oriented studies, but also from several different fields of application, and discuss the likely consequences for adsorption selectivities. Finally, we briefly summarize the data concerning thermally activated amide bond formation of adsorbed amino acids without activating agents. The reality of the phenomenon is established beyond any doubt, but our understanding of its mechanism and therefore of its prebiotic potential is very fragmentary. The review concludes with a discussion of future work needed to fill the most conspicuous gaps in our knowledge of amino acids/mineral surfaces systems and their reactivity.

Silica Surface Features and Their Role in the Adsorption of Biomolecules: Computational Modeling and Experiments

“…Other relevant data can be found in several more general reviews, such as Parida et al 204 (small organic molecules on silica, including some biomolecules), Lambert 205 (amino acids on divided oxides, written in a prebiotic perspective) or Fenoglio et al 165 (interaction of biomacromolecules with inorganic surfaces).…”

Chiral interactions of histidine in a hydrated vermiculite clay

“…Though the view that life arose through an "RNA World" is widely supported [3][4] , there is also an alternative hypothesis that proteins originated first on the early Earth 5 . Lambert has recently reviewed the organization and polymerization of amino acids at mineral surfaces 6 .…”

The Formation and Self‐Assembly of Long Prebiotic Oligomers Produced by the Condensation of Unactivated Amino Acids on Oxide Surfaces

“…[12] However, we studied also amorphous SiO 2 (see Materials in the SI) due to its importance in the abiotic polymerization of amino acids. [3,13] The primary results for the admission of Gly vapors onto HA (for comparison), SiO 2 and TiO 2 are summarized in Figure 1.…”