Peptides, prebiotic synthesis

Palchetti I, Mascini M (2005) Electrochemical Adsorption Technique for Immobilization of Single-Stranded Oligonucleotides onto Carbon Screen-Printed Electrodes. 261 27-43 Pascal R, Boiteau L, Commeyras A (2005) From the Prebiotic Synthesis of a-Amino Acids Towards a Primitive Translation Apparatus for the Synthesis of Peptides. 259 69-122 Paulo A, see Santos I (2005) 252 45-84 Perez EM, see Leigh DA (2006) 265 185-208 Perret F, see Coleman AW (2007) 277 31-88 Perron H, see Coleman AW (2007) 277 31-88 Pianowski Z, see Winssinger N (2007) 278 311-342 Piestert F, see Gansauer A (2007) 279 25-52... 

Pascal R, Boiteau L, Commeyras A (2005) From the Prebiotic Synthesis of a-Amino Acids Towards a Primitive Translation Apparatus for the Synthesis of Peptides. 259 69-122 Paulo A, see Santos I (2005) 252 45-84... 

Bujdak, J., Eder, A., Yongyai, Y., Faybikova, K., and Rode, B. M. (1995). Peptide chain elongation a possible role of montmorillonite in prebiotic synthesis of protein precursors. Orig. Life Evol. Biosph., 5,431 1. 

From the Prebiotic Synthesis of a-Amino Acids Towards a Primitive Translation Apparatus for the Synthesis of Peptides... 

Formamide is itself hydrolyzed by water, meaning that it persists only in a relatively dry environment, such as a desert. Desert environments recently proposed as being potential sites for the prebiotic synthesis of ribose18 may hold formamide as well. Since formamide boils at —400 K, a mixture of formamide and water, if placed in the desert, would lose its water over time and end up as a pool of formamide. Within this pool, many syntheses are thermodynamically favorable polypeptides from amino acids, nucleosides from sugars and bases, nucleotides from nucleosides and inorganic phosphate, and RNA from nucleotides. Indeed, phosphate esters are also spontaneously synthesized. This includes ATP (from ADP and inorganic phosphate), nucleosides (from ribose borates and nucleobases), peptides (from amino acids), and others.19-21... 

Pascal R, Boiteau L, Commeyras A. From the prebiotic synthesis of a-amino acids towards a primitive translation apparatus for the synthesis of peptides. Top Curr Chem 2005 259 69-122. 

Mellersh AR A model for the prebiotic synthesis of peptides which throws hght on the origin of the genetic-code and the observed chiraUty of hfe. Orig Life Evol Biosph 1993, 23(4) 261-274. 

Fortunately, my graduate research in biochemistry at Baylor College of Medicine, in Houston, involved studies on the mechanism of formic acid oxidation in animal tissues and on the incorporation of this one-carbon compound into nucleic acid components and their precursors. This provided me with experience in the use of isotopic tracers and the background in biochemical research which proved crucial, in later years, for unraveUng the intermediates and mechanisms of synthesis of purines and other compounds, when I discovered the prebiotic synthesis of adenine and other building blocks of nucleic acids, and a general pathway or method for the prebiotic formation of oligodeoxynucleotides and peptides. 

More exotic alternatives to nucleosides have been proposed based on the peptide nucleic acid (PNA) analogues of Nielsen and coworkers (93). Miller and coworkers (94) were able to demonstrate the facile prebiotic synthesis of all of the components of PNA under the same chemical conditions required for the synthesis of the purines or pyrimidines. Nevertheless there are maity alternative structures, which have not yet been investigated. 

If prebiotic peptides and/or proteins were in fact initially formed in aqueous solution (the hypothesis of biogenesis in the primeval ocean ), the energy problems referred to above would have needed to be solved in order for peptide synthesis to occur. As discussed in Sect. 5.3, there is some initial experimental evidence indicating that the formation of peptide bonds in aqueous media is possible. An important criterion for the evolutionary development of biomolecules is their stability in the aqueous phase. The half-life of a peptide bond in pure water at room temperature is about seven years. The stability of the peptide bond towards cleavage by aggressive compounds was studied by Synge (1945). The following relative hydrolysis rates were determined experimentally, with the relative rate of hydrolysis for the dipeptide Gly-Gly set equal to unity ... 

A combination of SIPS with the stabilising and synthesis-favouring properties of clay minerals was studied by Rode et al. (1999) in experiments involving dry/wet cycles. The simultaneous use of both SIPS and clay minerals as catalytically active surfaces led to peptides up to and including the hexamer (Gly)6. The question as to whether this technique fulfils prebiotic conditions can (within certain limitations) be answered positively, since periodic evaporation phases in limited areas (lagoons, ponds) are conceivable. The container material could have consisted of clay minerals. Further progress in the area of peptide synthesis under conditions which could have been present on the primeval Earth can be expected. 

Keywords Amino acid synthesis Peptide formation Prebiotic chemistry Coevolution... 

Because of their abilities in both peptide and nucleic acid oligomerization, N-phosphoryl amino acids could have played an important role in prebiotic chemistry on condition that a plausible pathway of synthesis of these compounds is made available. 

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