Evolution has been Disproven

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Mammuthus, I wish to clarify something about my chirality point. You state "once the first molecule was formed" referring to a replicator, such as DNA, but I ask how the first molecule was formed with specific chirality.

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Okay, fair question. Try this on for size: Bailey, JM 1998 RNA-directed amino acid homochirality FASEB Journal 12:503-507

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The phenomenon of L-amino acid homochirality was analyzed on the basis that protein synthesis evolved in an environment in which ribose nucleic acids preceded proteins, so that selection of L-amino acids may have arisen as a consequence of the properties of the RNA molecule. Aminoacylation of RNA is the primary mechanism for selection of amino acids for protein synthesis, and models of this reaction with both D- and L-amino acids have been constructed. It was confirmed, as observed by others, that the aminoacylation of RNA by amino acids in free solution is not predictably stereoselective. However, when the RNA molecule is constrained on a surface (mimicking prebiotic surface monolayers), it becomes automatically selective for the L-enantiomers. Conversely, L-ribose RNA would have been selective for the D-isomers. Only the 2' aminoacylation of surface-bound RNA would have been stereoselective. This finding may explain the origin of the redundant 2' aminoacylation still undergone by a majority of today's amino acids before conversion to the 3' species required for protein synthesis. It is concluded that L-amino acid homochirality was predetermined by the prior evolution of D-ribose RNA and probably was chirally directed by the orientation of early RNA molecules in surface monolayers. (emphasis added)
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So, given preexisting homochirality of RNA (and some particular conditions) homochirality of amino acids could occur. That doesn’t address the question of how homochirality arose.In addition, no mention is made of the amino acids polymerizing, so they appear to just be individual, free amino acids: that is, bonded to ribonucleotides but not to each other. Hence, no proteins or even polypeptides.

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Mammuthus, I wish to clarify something about my chirality point. You state "once the first molecule was formed" referring to a replicator, such as DNA, but I ask how the first molecule was formed with specific chirality.

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The same way they all do except without a protein catalyst.

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Wrong. The diagram you showed includes protein catalysts implicitly. Under non-enzymatic reactions carried out using racemic mixtures, both enantiomers of ribose are incorporated into growing chains leading to enantiomeric cross inhibition and termination of chain growth.By the way, another reason we can tell that your diagram uses some kind of catalyst is that 5’-activated RNA nucleotides tend to form "incorrect" bonds spontaneously: the two nucleotides preferentially bond between the 5’ carbon of one nucleotide and the 5’ carbon of the other; then between the 2' of one and the 5' of the other; and third, as in biological RNA, between the 3' and 5' carbons.Also, triphosphates are not what OOL researchers typically use when working with ribonucleotides.****************************
Off the topic, but I was at first confused by the diagrams. All diagrams I have seen of RNA/DNA show the 3’ carbon on the left of the 2’ carbon. It’s as if the diagrams are mirror-reversed from left to right. It took a few seconds for me to reorient.***************************
Gee, looks like I was more thrown off that I thought. I just noticed that the diagram shows "RNA polymerase", the biological enzyme that synthesizes RNA polynucleotides.[This message has been edited by DNAunion, 12-18-2003]