Evolution prebiotic

Buick R, Thornett JR, McNaughton NJ, Smith JB, Barley ME, Savage M (1995) Nature 375 574 Bungenberg de Jong H, Decker WA, Swan OS (1930) Biochem Z 221 392 Deamer DW (1998) Membrane Compartments in Prebiotic Evolution. In Brack A (Ed.) The Molecular Origins of Life. Cambridge University Press, p 189 Deamer DW, Dworkin JP (2005) Chemistry and Physics of Primitive Membranes. In Walde P (Ed.)... 

Plankensteiner, K., Righi, A., and Rode, B. M. (2002). Glycine and diglycine as possible catalytic factors in the prebiotic evolution of peptides. Orig. Life Evol Biosph., 32, 225-36. 

More refined laboratory experiments have provided good evidence that many of the chemical components of living cells, including polypeptides and RNA-like molecules, can form under these conditions. Polymers of RNA can act as catalysts in biologically significant reactions (as we discuss in Chapters 26 and 27), and RNA probably played a crucial role in prebiotic evolution, both as catalyst and as information repository. 

A large number of successful experimental studies which tried to work out plausible chemical scenarios for the origin of life have been conducted in the past (Mason, 1991). A sketch of a possible sequence of events in prebiotic evolution is shown in Figure 3. Most of the building blocks of present day biomolecules are available from different prebiotic sources, from extraterrestrial origins as well as from processes taking place in the primordial atmosphere or near hot vents in deep oceans. Condensation reactions and polymerization reactions formed non-in-structed polymers, for example random oligopeptides of the protenoid type (Fox... 

Y. Yamagata, H. Watanabe, M. Saitoh and T. Namba (1991). Volcanic production of polyphosphates and its relevance to prebiotic evolution. Nature (London), 352, 516-519. 

Deamer, D. W. (1998). Membrane compartments in prebiotic evolution. In The Molecular Origins of Life, ed. A.Brack. Cambridge, UK Cambridge University Press, pp. 189-205. 

The situation is somewhat reminiscent of a content-addressable memory [72], in which partial information is converted by the brain to recover the complete information. Such content-addressable memories [72], as well as the energy landscape [73] suitable for prebiotic evolution [74], have been modeled through spin glasses [75]. The energy landscape of spin glasses is also characterized by diversity and stability arising from randomness and frustration, which is quite distinct from the the physical mechanisms of short tubes in the marginally compact phase. 

As already mentioned, all these processes are basically driven by hydrophobic interactions. Formation of the vesicles is therefore a process which is accompanied by a decrease of free energy, as the coming together of lipophilic molecules to form a lipid cluster liberates water molecules from an energetically unfavorable situation and this brings about an increase of entropy. A similar situation is encountered in the binding processes of hydrophobic compounds onto the bilayer. It is a remarkable ordering process, a very basic one, and one which is under thermodynamic control. The question then automatically arises why should not Nature have used these processes as a start for the prebiotic evolution In fact, this... 

To make the existence of an RNA world as a step in prebiotic evolution feasible, not only self-replicating ribozymes are essential, but also a second type of catalytically active molecules. The transition from a world based on RNA catalysis to a world of protein enzymes demands ribozymes which are able to synthezise peptides from activated amino acids. 

Vijayan, M. (1980). Prebiotic evolution An approach to polymerisation based on crystal structures, FEES Lett. 112 135. 

In fact, the specific structure of DNA is not occasional, it is more likely to be the final result of natural selection. Cui conceived a possible route for the prebiotic evolution as follows. 

Biosynthesis, biogenesis synthesis by the metabolic reactions of a living organism. B. is distinct from the formation of compounds that appeared during prebiotic evolution by geological processes, or later in the laboratory under simulated primitive earth conditions. It must also be distinguished from the la-... 

Living systems have existed for more than a billion (10 ) years. ET reactions may have been of importance from the early beginning, since they are possible in proteins at a quite large distance ( 15 A) and hence there are no serious restrictions due to diffusion limitations for reactants and products. Efficient ET and PT systems must have developed spontaneously at an early stage of a chemical evolution (the prebiotic evolution), which preceded the biological evolution. 

The probability for drastic changes is small. RNA or photosynthetic reaction centers cannot have been created in seconds, just because all constituent atoms and molecules happened to meet at a certain time. Life may have started from a single cell, when such a cell finally existed after millions of years of prebiotic evolution. Still, there have been many possibilities for variation during the biological evolution. On another planet, plants may be red or black and ducks may be able to talk and use boats and sails. There is no reason to believe that present life is perfect. 

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