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→Claims of "Self-Replicating" Chemicals: In response to Philip's question.
Glucose does require life to make it outside of the lab, that we know of. RNA does occur naturally as well as RNA replicase, both molecules are not and should not be considered life (some prions are nothing more than a small strand of RNA with replicase or reverse transcriptase contained in a glob of lipids, would not be considered a protocell). DNA does occur outside of the cell as well, if the conditions are right (very rare), and is much more stable than RNA. However, it is a huge leap from these molecules to life. The whole reason why self replication and self formation of these molecules is possible is that the sum has a more stable energy state than the parts. When the parts of these molecules are found in solution at a neutral pH they react (due to the [[zwitterion]]ic forms of the bases). The chemistry involved for this is not difficult, if you would like I can go into further detail.--[[User:Able806|Able806]] 19:58, 14 January 2009 (EST)
Glucose does require life to make it outside of the lab, that we know of. RNA does occur naturally as well as RNA replicase, both molecules are not and should not be considered life (some prions are nothing more than a small strand of RNA with replicase or reverse transcriptase contained in a glob of lipids, would not be considered a protocell). DNA does occur outside of the cell as well, if the conditions are right (very rare), and is much more stable than RNA. However, it is a huge leap from these molecules to life. The whole reason why self replication and self formation of these molecules is possible is that the sum has a more stable energy state than the parts. When the parts of these molecules are found in solution at a neutral pH they react (due to the [[zwitterion]]ic forms of the bases). The chemistry involved for this is not difficult, if you would like I can go into further detail.--[[User:Able806|Able806]] 19:58, 14 January 2009 (EST)
: I know that RNA (and RNA replicase) are not life; my point was that they require living things to make them. You say that they occur naturally—do you mean in the absence of living things or other RNA? If so, can you please provide evidence of that? [[User:Philip J. Rayment|Philip J. Rayment]] 20:45, 14 January 2009 (EST)
: I know that RNA (and RNA replicase) are not life; my point was that they require living things to make them. You say that they occur naturally—do you mean in the absence of living things or other RNA? If so, can you please provide evidence of that? [[User:Philip J. Rayment|Philip J. Rayment]] 20:45, 14 January 2009 (EST)
::Yes, RNA and RNA replicase do occur in the absence of living things, they are just molecules. What kind of evidence would you like? How these molecules can form without a host cell? Evidence of these molecules in nature? I gave an example (prions) of RNA found in nature (some prions can catalyze the formation of RNA particles by just being in a solution with the bases and ribose). Prions are not alive, however they are organic. You can detect RNA everywhere but it would be almost impossible to tell if the fragment came from a living source or not, so you will find very little published information on that. The point is, RNA can form on its own (RNA is a lower energy state than its parts, this has been observed in the lab) and is the only known macromolecule that can both encode genetic information and also act as a biocatalyst (cellular ribosomes, where proteins are made, are mostly RNA), both points very important when talking of self replication. Here is a list of some resources if you would like to read more about it.<ref>Eigen, M., Gardiner, W., Schuster, P. & Winkler-Oswatitsch, The origin of genetic information. R. Sci. Am. 244, 88 (1981). </ref><ref>Westheimer, F.H. Polyribonucleic acids as enzymes. Nature 319, 534 (1986). </ref><ref>Guerrier-Takada, C., Gardiner, K., Marsh, T., Pace, N. & Altman, S. The RNA moiety of ribonuclease P is the catalytic subunit of the enzyme. Cell 35, 849 (1983). </ref><ref>Guerrier-Takada, C. & Altman, S. Catalytic activity of an RNA molecule prepared by transcription in vitro. Science 223, 285 (1984).</ref><ref>Kruger, K. et al. Self-splicing RNA: autoexcision and autocyclization of the ribosomal RNA intervening sequence of Tetrahymena. Cell 31, 147 (1982). </ref><ref>Cech, T.R. Self-splicing RNA: implications for evolution. Int. Rev. Cytol. 93, 3 (1985). </ref><ref>Zaug, A.J. & Cech, T.R. The intervening sequence RNA of Tetrahymena is an enzyme. Science 231, 470 (1986). </ref><ref>Sharp, P.A. On the origin of RNA splicing and introns. Cell 42, 397 (1985). </ref><ref>White, H.B. III, Coenzymes as fossils of an earlier metabolic state. J. molec. Evol. 7, 101 (1976). </ref><ref>K. S. Huang, N. Carrasco, E. Pfund, and S. A. Strobel. Transition State Chirality and Role of the Vicinal Hydroxyl in the Ribosomal Peptidyl Transferase Reaction. Biochemistry 47, 8822-8827(2008)</ref><ref>S. A. Strobel. Ribonucleic general acid. Nature Chem. Biol. 1, 5-6 (2005)</ref><ref>J. Cochrane, R. Batey and S.A. Strobel. Quantitation of free energy profiles in RNA-ligand interactions by nucleotide analog interference mapping. RNA. 10, 1282-1289 (2003)</ref> If you would like I can provide a energy state diagram showing the states for each part and then for the total and provide the mechanisms that the molecules go through to achieve the final formation, all of which are progressively lower in energy therefore allowing for the formation of RNA to be a highly favorable chemical reaction.--[[User:Able806|Able806]] 10:58, 15 January 2009 (EST)
==References==
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