This book provides an interdisciplinary review of one of the great unsolved mysteries that has fascinated scientists for over 150 years: the origin of chirality in biomolecules. It was Pasteur who first initiated the search for a deterministic theory to explain the ‘handedness’ of biomolecules. His theory, that a ‘dissimetric’ force was involved, was correct in essence but he never saw the fruits of his labour. Current thinking tells us that asymmetry in the universe has its origins in the forces that unfolded after the Big Bang and, more specifically, the weak force. Being ‘left handed’, the weak force imprinted its signature on the evolving Universe. However, at the molecular level, the weak force does not provide a straightforward explanation of biomolecular homochirality. In fact, it is yet to be proved beyond doubt that a causal link exists at all. Many alternative theories have been put forward, some of them resting on solid ground, but all lacking definitive experimental evidence to back them up. Some postulate that the handedness of molecules in the biosphere arose by chance but this is hard to test. Others rely on discovering life on similar planets and making comparisons with Earth. Alternative theories have emerged from a range of backgrounds including geology, biology, chemistry, physics and astronomy. Current advances in fields as diverse as space exploration, prebiotic chemistry and high-energy physics may help to provide an answer. Important pieces of information will come from observations at the two frontiers of science: outer space and the subatomic world. Observation of distant planets, galaxies, and even actual sampling of celestial objects from beyond the solar system are projects currently underway. At the other end of the spectrum, there are experiments that study the elemental properties of matter, such as symmetry, and interactions with the fundamental forces. All these efforts will render their fruits soon. This volume unifies all the theories of the origin of biomolecular homochirality together in one source. The various chapters focus on chance mechanisms, physical forces such as the ‘weakinteraction’, fluid dynamics, amplification of chirality, the organic contents of meteorites and comets and, finally, the physical view of an intrinsically asymmetric universe. This complete, interdisciplinary review of an intriguing subject condenses a large and disparate range of contributions from journals in almost every scientific field. The various theories have been organized, interrelated and explained in a unified way. One of the book’s strengths is its extensive use of graphic material to aid understanding the many subjects covered. It is fundamental, comprehensive and structured to be accessible for educational purposes.
Table des matières
Chapter 1 Introduction and historical background. Chapter 2. Classification of the theories of the origin of biomolecular homochirality: Chance theories; Amplification of tiny stochastic imbalances; The racemic state; Polymerizations above a critical chain length macromolecules; Deterministic theories. Chapter 3. The concept of chirality: The basic symmetry operations; The space inversion: the Parity operator: ; The time reversion: the Time reversal operator: ; The charge conjugation: the Charge conjugation operator: ; The failure of the experiments of L. Pasteur, P. Curie and others. Experiments in the absence of chirality. Experiments under the influence of false chirality or true chirality; Absence of chiral field; Experiments under false chiral influence; Experiments under true chiral influence; Expected effect of true and false chirality on molecules. Chapter 4. Chiral physical forces: The Weak Interaction and the Parity Violation; Introduction. The Fundamental Interactions: Gravitational, weak interaction, electromagnetic and strong interaction; The ?-decay; Parity violation; Experimental confirmation of the parity violation in weak interactions; The ?+ and ?- decays and the conservation of the symmetry operator ; The Principle of Invariance; Unification of forces; The Electroweak Theory; The neutral Z¦ boson; Quantification of the Parity violation in molecules: ?Epv; Experimental tests for parity-violating energies ?Epv in molecules; ?-Radiolysis; Asymmetric photolysis and photosynthesis; Circularly polarized light. Circular dichroism; The magnetochiral effect; Fluid Dynamics: Vortex motion. Chapter 5. Mechanisms of Amplification: Autocatalysis; The Frank Model; Theoretical Models derived from Frank’s original model; Autocatalytic amplification of the weak force; Amplification of Chirality in chemical reactions; Non-linear effects; Asymmetric autocatalytic reactions; Self-replication; Amplification of the chirality by cooperative forces: growing polymers and supramolecular assembles; Amplification of the chirality in polymerizations; Amplification of the chirality in supramolecular assembles; The Yamagata cumulative mechanism; The Salam phase transition; Amplification of scalemic compounds. Eutectic mixtures; Solubility properties; Sublimation proterties; Amplification of chirality in serine octamers; Homochiral preference and chiral amplification; Chemistry of serine octamers; Sublimation experiments. Chapter 6. Spontaneous Symmetry Breaking: Spontaneous Symmetry Breaking in Crystallizations. Chapter 7. Outside Earth: Meteorites and Comets: Meteorites; Comets. Chapter 8. Other local deterministic theories: Chiral crystals and faces on crystals; Quartz; Calcite, gypsum, clay minerals and others; Organic crystals: Glycine; Two-dimensional chirality. Chapter 9. Intrinsic Assymetry of the Universe: The Arrow of Space-Time and the unequal occurrence of matter and antimatter. Amplification of the chirality in polymerizations; Amplification of the chirality in supramolecular assembles; The Yamagata cumulative mechanism; The Salam phase transition; Amplification of scalemic compounds. Eutectic mixtures; Solubility properties; Sublimation proterties; Amplification of chirality in serine octamers; Homochiral preference and chiral amplification; Chemistry of serine octamers; Sublimation experiments. Chapter 6. Spontaneous Symmetry Breaking: Spontaneous Symmetry Breaking in Crystallizations. Chapter 7. Outside Earth: Meteorites and Comets: Meteorites; Comets. Chapter 8. Other local deterministic theories: Chiral crystals and faces on crystals; Quartz; Calcite, gypsum, clay minerals and others; Organic crystals: Glycine; Two-dimensional chirality. Chapter 9. Intrinsic Assymetry of the Universe: The Arrow of Space-Time and the unequal occurrence of matter and antimatter.
A propos de l’auteur
Albert Guijarro received his MSc and Ph D from the University of Alicante. He then spent three years at the University of Nebraska before returning to Alicante where he became Associate Professor in 2003. His current research interests are in the field of physical organic chemistry, specifically in the study of highly reduced anionic electron systems. He is co-author of 32 papers, has supervised four Ph D students, and has participated in/directed numerous research projects. He is a research member of the ISO (Institute of Organic Synthesis) in Alicante and co-founder of MEDALCHEMY, S.L. Miguel Yus is based at the University of Alicante where he is currently head of the Organic Synthesis Institute (ISO). He has been visiting professor at various institutions including ETH-Zentrum and the Universities of Oxford, Harvard, Uppsala, Tucson, Okayama, Paris and Strasbourg. Professor Yus is on the Advisory Board of numerous learned journals and is Regional Editor of Letters in Organic Chemistry. He is co-author of over 400 papers, has given more than 150 lectures and supervised 43 Ph D students. He has received accolades including the Japan Society for the Promotion of Science Prize, the French-Spanish Prize of the SocietÚ Franþaise de Chimie, the C.A. Stiefvater Memorial Lecture Award, the Nagase Science and Technology Foundation fellowship, and the Cellchem Lectureship. He is co-founder of MEDALCHEMY, S.L.
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