From: rokimoto557@gmail.com   
      
   On 8/21/2025 6:26 PM, MarkE wrote:   
   > A perspective on OoL from Dr. Edward T. Peltzer. Quotes following are   
   > interview excerpts.   
   > _______   
   >   
   > I did have many discussions with Miller and Bada on many subjects, but   
   > the issues of pre-biotic chemistry and the origin of life were the most   
   > common. Both were excellent chemists. You could ask them about almost   
   > anything and they would have an answer or know where one could look to   
   > find out. In some cases, I suspected they already knew, but wanted to   
   > give me the experience of scouring the library to find out. One could   
   > say that they taught me everything I new about prebiotic chemistry at   
   > the time.   
   >   
   > During his doctoral studies at the Scripps Institution of Oceanography   
   > (SIO), he was mentored by two luminaries in prebiotic chemistry: Stanley   
   > Miller, renowned for the Miller-Urey experiment simulating early Earth   
   > conditions, and Jeffrey Bada, an expert in the field of amino acid   
   > racemization and a prominent figure in the study of organic compounds in   
   > meteorites.   
   >   
   > As for the various individual [OoL] theories, here are a few of the   
   > fatal errors. Hydrothermal vents do not make organic compounds, they   
   > destroy them.   
   >   
   > Surface based synthesis might yield a few useful compounds, but many   
   > compounds with a diverse range of functionality are needed for the first   
   > organism. RNA is too unstable outside a living cell to offer much hope   
   > of it doing anything in the pre-biotic soup if somehow it was formed   
   > (which is exceptionally unlikely).   
   >   
   > My least favorite theory among all the options is the lipid world.   
   > Assuming that one could get a collection of similar chain length fatty   
   > acids bonded to glycerol to make triglycerides (which itself is highly   
   > unlikely in the pre-biotic soup of randomly generated compounds), then   
   > one could form an artificial vesicle (alternatively called a coacervate   
   > or liposome) with a lipid bilayer film. What you then have is not much   
   > more than a “soap bubble.” There is no interior metabolism, no ion-   
   > transport pathways in the “membrane”; it is nothing more than a film-   
   > coated droplet. How it would acquire an internal metabolism, etc., is   
   > anyone’s guess. But guesses, as entertaining as they might be, are not a   
   > scientific explanation of how life arose abiotically.   
   >   
   > Random undirected chemistry does not yield biopolymers. Organisms need   
   > proteins, DNA &/or RNA, polysaccharides, etc. These polymers are uniform   
   > in that they are composed of a monomeric class of compounds bound   
   > together in very specific ways: proteins are chains of amino acids   
   > linked by peptide bonds; DNA & RNA are chains of nucleotides linked by   
   > phosphate bridges; polysaccharides (e.g., starch & cellulose) are chains   
   > of glucose molecules linked by α-(1,4) glycosidic bonds in starch   
   > (amylose) and β-(1,4) glycosidic bonds in cellulose. Random, undirected   
   > chemical reactions do not yield these pure polymers. Instead, they yield   
   > polymers formed by random condensations of whatever compounds are at   
   > hand, producing high molecular weight compounds without a well-defined   
   > structure. Examples of this are fulvic and humic acids, melanoids, etc.   
   > Their structures are complex, involve monomers from a variety of   
   > compound classes and without a common bonding pattern. As such, they   
   > exhibit little to no biological activity and store no information.   
   >   
   > The biggest challenge of all will be to convince the folks who dream up   
   > the various theories for the origin of life to include the impact of   
   > competing reactions on their pathways as opposed to writing “just so   
   > stories.”   
   >   
   > The origin of homochirality (D-sugars, L-amino acids, etc.) has proved   
   > to be a difficult problem to solve. The goal needs to be chiral purity   
   > otherwise just a single wrong isomer can completely foul the   
   > functionality of the biopolymer (protein, DNA/RNA, etc.). Homochirality   
   > is always up against racemization, the process by which chiral molecules   
   > get mixed with their mirror images (enantiomers). Any such lack of   
   > purity among chiral molecules is deadly to life. All three of the   
   > proposed processes to achieve homochirality fail for such reasons.   
   > First, they are slow and only achieve a partial enrichment of the   
   > desired form. Second, racemization reactions work faster to undo this   
   > enrichment. What little progress is made is quickly lost. Third, the   
   > racemization rate increases with temperature. So, the condition needed   
   > to speed-up other synthesis processes works against homochirality. The   
   > source of homochirality remains an unsolved mystery.   
   >   
   > Another problem for abiotic synthesis is that some amino acids have two   
   > amino groups, and some have two carboxylic acid groups. This leads to   
   > the possibility that the carboxlic acid group can bind with the wrong   
   > amino group (or vice-versa) and thus branches can form in undirected   
   > syntheses. None of the proteins in living systems have “branches” as   
      
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