Chirality and Life (eBook)

Part I. Physico-chemical Principles 1. Introduction2. Formation of primordial bioorganic molecules  3. Hidden Aspects of Chirality 4. RNAs and their constituents                                                       5. Proteins and their constituents                                                   6. Membranes7. Compounds Required for Life                                                        Part II. Scenarios of Ancient Worlds8. The RNA World Involves RNA as a First Genetic System9. Peptide and Protein World10. Combinations of the RNA with the peptide world      11. The Precellular World of Viruses                                              12. Combinations of Different Worlds                            13. The Iron Sulfide World of Proto-Metabolism                       14. The Genetic Code

Chirality and Life 3
Preface and Acknowledgments 5
Contents 7
Abbreviations 9
Part I: Physicochemical Principles 11
Chapter 1: Introduction 12
Chapter 2: Formation of Primordial Bioorganic Molecules 15
Chapter 3: Hidden Aspects of Chirality 16
3.1 Asymmetric UV Photolysis of a Racemic Amino Acid 17
3.2 Occurrences of a-Methyl Amino Acids in Meteorites 18
3.3 Partial Transfer of Enantiomeric Excess of a-Alkyl Amino Acids to Standard Amino Acids 20
3.4 Amplification of Enantiomeric Concentrations Without Catalysis 20
3.5 Thermodynamic Control of Asymmetric Amplification in Amino Acid Catalysis 20
3.6 Asymmetric Organocatalysis: Special Importance of Chiral Proline 21
3.7 Amplification of Ribonucleosides 22
3.8 The Soai Reaction 23
3.9 Spontaneous Formation of Chiral Crystals of Cytosine During Mechanical Stirring 25
3.10 The Butlerov or Formose Reaction 26
3.11 Conclusions from the Aspects of Chirality 27
Chapter 4: RNAs and Their Constituents 29
4.1 Nucleobases 29
4.2 Carbohydrates 29
4.3 Phosphodiester 30
4.4 Classes of RNA 31
4.4.1 Transfer RNA 31
4.4.2 Ribosomal RNA 32
4.4.3 Messenger RNA 32
4.4.4 Micro and Small RNAs 33
4.4.5 RNA Modifications 33
Chapter 5: Proteins and Their Constituents 34
5.1 Amino Acids 34
5.2 Posttranslational Modification 37
5.3 Protein Structural Motifs: a-Helix, beta-Sheet, beta-Turns 37
5.4 Protein Domains 37
Chapter 6: Membranes 38
6.1 Long Chain Fatty Acids Esterified with Phosphoryl Groups: Lipid Bilayer of Bacterial Membranes 38
6.2 Prenyl Chains Linked to Di-Isoprene Phosphate via Ether Bridges: Lipid Mono- and Bilayers of Archaeal Membranes 38
Chapter 7: Compounds Required for Life 43
7.1 Water 43
7.2 Coenzymes 43
Part II: Scenarios of Ancient Worlds 46
Chapter 8: The RNA World: RNA as a First Genetic System 47
Chapter 9: Peptide and Protein Worlds 49
Chapter 10: Combination of Ribozymes with Peptides: The Evolving RNA Peptide World 50
Chapter 11: The Precellular World of Viruses 53
Chapter 12: Combinations of Different Worlds 55
Chapter 13: The Iron Sulfide World of Protometabolism 56
Chapter 14: The Evolution of the Genetic Code 60
References 62
Subject Index 64