Which doesn’t mean there is no hope or no information. Read on.
I had to write just to defend the poor chemist, John D. Sutherland. The problem of making ribose and proteins-a la Miller and Urey, is that the reaction removes a water molecule when making the bond between amino acids–so it only works in a dry environment–on the other hand, the other reactions for making glycine or amino acids need a wet environment. If I recall correctly, the same dichotomy applies to synthesis of RNA, DNA and nucleotides, in which some bonds are broken by water, some are made in water.
In a very similar way, heat is needed to drive some reactions forward (endothermic), but also breaks other bonds driving reactions backward (exothermic). So both water and heat are these Janus-faced gods that are both necessary and deadly to biotic chemistry.
In a living cell, enzymes perform the magic to drive reactions in the absence of heat or water, but for abiotic chemistry, one can’t invoke them. These conundra are just two of many reasons why Origin-of-Life people are such a glum bunch, and despite 60 years since Miller-Urey, they haven’t solved the problem of abiotic synthesis of biomaterials.
Sutherland’s research was finding a one-step synthesis for these chemicals that didn’t involve water or heat. He’s been working on it for at least a decade. A breakthrough was announced in Nov 2009 in Nature “Synthesis of activated pyrimidine ribonucleotides in prebiotically plausible conditions,” where they said :
The starting materials for the synthesis-cyanamide, cyanoacetylene, glycolaldehyde, glyceraldehyde and inorganic phosphate-are plausible prebiotic feedstock molecules, and the conditions of the synthesis are consistent with potential early-Earth geochemical models. Although inorganic phosphate is only incorporated into the nucleotides at a late stage of the sequence, its presence from the start is essential as it controls three reactions in the earlier stages by acting as a general acid/base catalyst, a nucleophilic catalyst, a pH buffer and a chemical buffer. For prebiotic reaction sequences, our results highlight the importance of working with mixed chemical systems in which reactants for a particular reaction step can
also control other steps.”
In this “plausible mixture”, the phosphate turns out to be critical in doing many of the jobs of water. The “heat” problem is solved by adding UV light–a peculiar kind of heat as anyone with a sunburn can tell you–which can be tuned to the reaction that needs it without triggering the degradation that doesn’t need it. The recent bit of pom-pom waving involves the use of hydrogen cyanide directly instead of the organo-cyanide molecules, which is “more plausible” than the previous plausible mixture, and no doubt every year we will be subjected to greater and greater claims of plausibility with nary an acknowlegement of implausibility.
Now like you, I’m not a big fan of one-pot-pasta, but the mere fact Sutherland has accomplished this job is astonishing. For 60 years, no one had been able to fix Miller-Urey, and Sutherland has finally made some progress. This cautions all of us against extrapolating from lab difficulties to theoretical impossibilities. Now I don’t think this is really a “plausible” mixture for OOL research, but it does highlight the sort of fine-tuning necessary for the chemistry to work. Like Behe’s Edge of Evolution , it quantifies the amount of chemical information in a step which previously was a dreamy “plausible scenario”. And the information content is enormous.
See also: Suzan Mazur: A non-linear language needed for life? Meet Luis Villareal (“It’s clear to me from reading your papers that you have issues with neo-Darwinism.”)
Understanding the problems with origin of life research
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