Valin Posted February 15 Share Posted February 15 Feb. 14 2021 In this prologue episode, Dr. James Tour explains why he is addressing abiogenesis and common misconceptions in this series of lectures. After providing the outline for the course, Dr. Tour provides a sneak peak of the upcoming critique. Video Index: 00:00 - Introduction & Dr. Tour's Background 02:52 - Some Background on the Series 07:01 - Reasons & Intent of this Abiogenesis Series 12:22 - Unskilled & Unaware 14:29 - "Biochemistry"? And what's in a name? 17:29 - Abiogenesis Series Outline 19:53 - Thermodynamics Addendum 22:12 - Origin of Life: Low Entropy & High Energy 25:03 - Closing Remarks & What's Link to interview with Dr. Brian Miller: https://youtu.be/RJeUH7IhQHo (Snip) Link to Professor Dave's video: https://youtu.be/SixyZ7DkSjA Link to post Share on other sites
Valin Posted February 16 Author Share Posted February 16 Feb. 15 2021 In this episode, Dr. James Tour defines abiogenesis and describes the characteristics for life, including a discussion on early Earth's conditions and challenges for prebiotic chemistry. After reviewing the four classes of molecules needed for life, Dr. Tour elaborates on the synthesis problems currently facing today's origin of life researchers. Video Index: 00:00 - Introduction 00:44 - Reasons & Intent of this Abiogenesis Series 02:34 - Abiogenesis Defined 04:39 - Life's Characteristics 06:40 - Early Earth Conditions 11:01 - Prebiotic Chemistry Defined 12:23 - Four Classes of Molecules and their Building Blocks 14:37 - Car Parts: Assembly, Collection, Degradation 17:30 - The Synthesis Problem 22:54 - Closing Remarks: "Molecules Don't Care About Life" and What's Next in this Series | Addressing Abiogenesis & Common Misconceptions ====== (Snip) Link to post Share on other sites
Valin Posted February 17 Author Share Posted February 17 Feb. 16 2021 In this brief episode, groundwork is still being laid, as Dr. James Tour explains the early Earth primordial soup concept and enlightens the listener on the layperson's understanding. Dr. Tour then shows what the contemporary belief is, what levels of education it is held, and where it is taught. Video Index: 00:00 - Introduction 00:42 - Reasons & Intent of this Abiogenesis Series 02:54 - Primordial Soup, Laypersons, and Talking Points 05:12 - Education Confirmation: "Not too bad at all" (and sans correction) 08:31 - A Survey on Primordial Soup 11:52 - Summary and What's Next (Snip) Link to post Share on other sites
Valin Posted February 18 Author Share Posted February 18 Feb. 17 2021 In this episode, Dr. James Tour examines hyperbole surrounding origin of life claims. Beyond a mere attribution to the press for creating hype, Dr. Tour looks into the published works by researchers themselves, discovering a more proper attribution of the source. He then elaborates how this snowballs further by the press into confusion by professors and laypersons. Finally, some agreement on prebiotic relevance is revealed. Video Index: 00:00 - Introduction 00:36 - Reasons & Intent of this Abiogenesis Series 02:24 - To be clear: Not just press. Researchers too. 04:32 - Example: This is common chemistry? 24:19 - Example: How close are we? 28:14 - Example: OOL reproduced in the lab? 32:55 - Example: This is self-replication? 34:44 - Example: Simple Extant Imaginations 38:07 - Example: Fair Representation? 39:19 - Example: Deck Stacking, No Resemblance, Misappropriation 45:42 - Prototurkey for Thanksgiving 47:15 - Agreement on Prebiotic Relevance Requirement 48:18 - Summary and What's Next (Snip) Link to post Share on other sites
Valin Posted February 18 Author Share Posted February 18 Related........... Feb. 17 2021 Link to post Share on other sites
Valin Posted February 19 Author Share Posted February 19 Feb 18 2021 Diving into the science on homochirality, Dr. James Tour teaches the core chemistry concepts of enantiomers and chirality, exposing enormous challenges in the prebiotic synthesis and resolution of the molecules needed for life. By digging into the cited video's only provided reference, Dr. Tour puts ink on paper and shows how the devil is in the details when it comes to proper interpretation of the data. Finally, Dr. Tour touches on the stereoisomeric challenges facing synthetic chemists doing origin-of-life, prebiotic research. Video Index: 00:00 - Introduction 00:37 - Recall Dunning-Kruger 01:06 - Reasons & Intent of this Abiogenesis Series 03:01 - Enantiomers, Diastereomers, and Chirality 07:36 - Resolution of Enantiomers, Methods, and Requirements 09:26 - Quoting the Only Reference Cited 11:20 - Homochirality Explained 14:17 - Digging into the Misread of that Reference 23:26 - Summary and What's Next (Snip) Link to post Share on other sites
Valin Posted Sunday at 03:26 AM Author Share Posted Sunday at 03:26 AM Feb 20 2021 n this episode on carbohydrates, Dr. James Tour comes right out of the gate refuting the claimed triviality of biomolecular synthesis. Rather than agree with the claim on the ease of polysaccharide synthesis, Dr. Tour explains the difficulty of their creation, including homochirality and the prebiotic problems facing multiple isomers, blind pathways, and polymerization and positioning. Also, Dr. Tour points out the fallacy of borrowing products from biology in prebiotic syntheses, and the challenge of early Earth blindly working through unfathomable procedures. Video Index: 00:00 - Introduction 00:48 - Reasons & Intent of this Abiogenesis Series 02:45 - Correcting the Record on Polysaccharide & Biomolecular Synthesis 07:28 - Before Nucleotides, Ribose 09:48 - Cannizzaro vs Formose 13:01 - Eschenmoser's attempt 19:47 - Time & Equilibrium 22:18 - "homo-DNA" instead 23:36 - Real world difficulties 25:53 - Polymerization - Hooking the Sugars 42:36 - Summary and What's Next (Snip) Link to post Share on other sites
Valin Posted Tuesday at 05:00 AM Author Share Posted Tuesday at 05:00 AM Feb. 22 2021 n this episode, Dr. James Tour pauses and goes back to the basics, in a most literal sense. The matter at hand is not merely synthesizing the four classes of compounds needed for life – polysaccharides/carbohydrates, proteins, nucleic acids, and lipids – but rather their respective building blocks – monomeric sugars; amino acids; nucleotides; and fatty acids and glycerol. When restricted to prebiotic chemicals and methods, and with no store from which to purchase these building blocks while remembering homochirality, is biomolecular synthesis easy? Video Index: 00:00 - Introduction 00:39 - Reasons & Intent of this Abiogenesis Series 03:25 - Car Parts' Building Blocks 07:16 - "Easy" Misconception Regarding Building Block Syntheses 11:56 - Cellular Building Blocks & their origin 14:01 - Convenience vs Prebiotic Rocks & Atmosphere 15:59 - Summary and What's Next (Snip) Link to post Share on other sites
Valin Posted 8 hours ago Author Share Posted 8 hours ago Feb. 24 2021 In this episode, Dr. James Tour identifies gross speculatory language and refers to published literature stating the implausibility of the sudden emergence of peptides from amino acids. Without careful activation, side chain protection, and water-free conditions, amino acids do not polymerize into peptides. Dr. Tour also dispels the view that human-made synthesizers, which were not present on prebiotic earth, somehow render polypeptide synthesis as trivial, let alone the fact that amino acids themselves have never been prepared in homochiral fashion using a prebiotically relevant route. Finally, with no solution to the amino acid sequence that comprises functional proteins, Dr. Tour then shows how some ignore the sequence specificity question necessary for the informational code, and how this dilemma is being pushed to the extraterrestrial in a plea to the heavens. Video Index: 00:00 - Introduction 00:47 - Reasons & Intent of this Abiogenesis Series 02:58 - On Speculatory Fallacies 06:26 - Synthetic Chemists: "Inconceivable" 10:36 - Interesting Proposal Still Falls Short 12:45 - Basics: Amino Acids, Peptides, Proteins 16:47 - Separating Amino Acids and Peptides 18:29 - Solid-Phase Peptide Synthesis 22:53 - Peptide Structures Explained 26:03 - Protein Synthesizer Machine Prebiotically Relevant? 30:57 - Peptide Synthesis: Requirements and Efficiency 38:23 - Pushing the Amino Acid Sequence to the Celestial 48:13 - Summary, Equilibrium Memo, and What's Next (Snip) Link to post Share on other sites
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