Mineral Surface Directed Membrane Assembly

Abstract

The transition from non-living to living matter may have resulted from the self-organizing properties of organic molecules and their interactions with a chemically rich inorganic environment. We have shown that a solution containing RNA, fatty acids and clay produces structures that contain a potentially catalytic surface (clay) and a potential informational biopolymer (RNA) encapsulated within a membrane. This highlights the ability of mineral surfaces to bring together and organize key components of primordial life. We have extended our analysis of mineral-mediated vesicle catalysis to include other natural minerals and synthetic surfaces of varying shape, size, and charge density. Our results show that while RNA polymerization on minerals may be restricted to the surface environment provided by montmorillonite, vesicle formation is enhanced in the presence of disparate types of surfaces. A model is presented in which new sheets of amphiphiles form just proximal to a surface. Similar interactions between amphiphiles and minerals on early Earth may have resulted in the encapsulation of a diverse array of mineral particulates with catalytic properties.

Catalysis in the Primordial World

“…The hypothesis is experimentally supported by studying vesicle formation in the presence of various minerals, e.g., pyrite and montmorillonite. 159,160 However, experiments aimed at synthesis of amino acids and nucleic bases from CO 2 using FeS/H 2 S system failed, 161 and it was shown that sulphide minerals stimulate degradation of RNA by catalysing the hydrolysis of phosphodiester bonds. 146 …”

Stochastic Prebiotic Chemistry within Realistic Geological Systems

“…Other studies on membrane self-assembly processes which allow cellular compartmentalisation have been carried out with amphiphiles ( [75] and references therein). Hanczyc and colleagues [76] found that the presence of naturally occurring clay minerals, such as montmorillonite, can help in the assemblage of vesicles and, in the process, bring bound RNA …”

On the Emergence of a Proto-Metabolism and the Assembly of Early Protocells

“…Many mineral surfaces promote vesiculation (Hanczyc et al 2003;Hanczyc et al 2007), in this case the mineral surfaces seems to facilitate bilayer formation by promoting ordering of molecules on their surfaces in specific configurations.…”