From: rokimoto557@gmail.com   
      
   On 8/25/2025 9:23 PM, Chris Thompson wrote:   
   > sticks wrote:   
   >> On 8/23/2025 8:06 AM, MarkE wrote:   
   >>> On 22/08/2025 11:19 pm, RonO wrote:   
   >>>> 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-   
      
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