Chapter 5 in “Astrobiology: Emergence, Search and Detection of Life” (V.A. Basiuk Ed.), American Scientific Publishers, pp 97–154 Zagórski

ZP (2010b) Ranking of sites on early earth PX-478 price as cradles for life. Orig Life Evol Biosph 40:490–494 Zagórski ZP (2010c) Possible role of radon in prebiotic chemistry and in early evolution of Life on Earth. Nukleonika 55:555–558″
“Erratum to: Origins of Life and Evolution of Biospheres 41:621–632 DOI 10.1007/s11084-011-9261-2 The legend for figure 2 was accidentally replaced with the legend of figure 1. The find more correct legend reads: Figure 2: Rooted phylogeny of aliphatic aminoacyl-tRNA synthetases. IleRS and ValRS are sister paralogs, with LeuRS (not shown) included as outgroup. Domains within each paralog (colored) show differing topologies due to deep horizontal gene transfer events.”
“Introduction A common feature of all cellular life is the presence of boundaries composed of amphiphilic molecules that self-assemble as bilayers. These cell membranes are composed of phospholipids mixed with polycyclic compounds such as cholesterol, but it is likely that the first membranes consisted of much simpler amphiphilic species. Potential sources of these amphiphiles include synthesis through Fischer-Tropsch reactions associated with volcanism (McCollom and Seewald 2007; Rushdi and Simoneit

selleck chemicals llc 2001; Simoneit 2004) as well as extraterrestrial delivery of organic compounds during Rebamipide the early history of the solar system and the young Earth. For instance, Chyba and Sagan (1992) estimated the extraterrestrial delivery of carbon to be in the order of 109 kg per year during the early heavy bombardment phase. Carbonaceous meteorites contain pristine organic compounds, among them are monocarboxylic acids (Sephton 2002). These range from C2 (acetic acid) to C12 (dodecanoic acid), with decreasing abundance as

the carbon number increases. A suite of compounds extracted from the Murchison meteorite by organic solvents are amphiphilic and assemble into membranous vesicles (Deamer 1985; Deamer and Pashley 1989). From these and other studies, it seems likely that monocarboxylic acids (i.e. fatty acids) with chain lengths ranging between 8 and 12 carbons were able to be constituents of primitive cell membranes on the early Earth. In support of this hypothesis it was previously shown that pure fatty acids are able to self-assemble into vesicles in aqueous dispersions when the pH is similar to the pKa, because deprotonated and protonated head groups form hydrogen bonds that stablize bilayer structures (Monnard and Deamer 2002, 2003). Vesicles composed of fatty acid are dynamic assemblies: molecules constantly flip-flop between the inner and outer leaflets and rapidly exchange between the bilayer and the surrounding medium. Fatty acid vesicles can also grow and divide under simulated prebiotic conditions (Zhu and Szostak 2009).