After the great achievements in the field of molecular foundations of genetics and protein synthesis, molecular biology undertook the successful deciphering of a number of other important biological problems. By this time ecology in its various branches was far enough advanced to tackle the problems arising at the level of molecular biology. The monograph of Professor Alexandrov, which takes as an example the adaptation of organisms to habitat temperatures, presents a vivid picture of this major ecological problem as viewed at the cellular and molecular levels. As main theme of the book the author advances a hypothesis on a correlation between the level of conformational flexibility of protein molecules and the temperature ecology of a species, as a result of which the protein molecules are maintained in a semilabile state. This principle may also be applied to other factors of the environment which affect the level of flexibility of protein macro molecules. The principle of semistability is shown to be applicable also to the nucleic and fatty acids.

Inhalt

1. Modificational Changes of the Primary Thermoresistance of Cells.- 1.1 The Primary Thermoresistance of Cells.- 1.2 The Level of Primary Thermostability of Cells and Habitat Temperature.- 1.3 Changes in the Cellular Primary Thermostability Produced by Non-Temperature Factors.- 2. Genotypic Changes of the Primary Thermoresistance of Cells.- 2.1 Animals.- 2.2 Plants.- 2.3 Microorganisms.- Summary.- 3. Variations in Thermostability of Protoplasmic Proteins as a Basis for Changes in the Level of Primary Cellular Thermoresistance.- 3.1 Are the Shifts in Cellular Thermoresistance Accompanied by Alteration of the Cellular Resistance to Other Injurious Agents ?.- 3.2 Changes in Protein Thermostability Caused by Isolation of the Proteins From Cells.- 4. Adaptive Modifications of Conformational Flexibility of Macromolecules as a Basis for Changes of the Protein Thermostability.- 4.1 The Correlation Between Thermostability of Proteins and the Environmental Temperature Conditions of a Species' Life Cannot be Explained by an Adaptive Significance of the Level of Thermostability.- 4.2 A Hypothesis of the Adaptive Significance of a Correspondence of the Conformational Flexibility Level of the Protein Molecules to the Environmental Temperature Conditions of Species' Life.- 4.3 The Level of Conformational Flexibility of Protein Molecules and Their Resistance to Non-Thermal Agents.- 5. The Plausible Points of Application of the Natural Selection During Alteration of a Correspondence Between the Level of Conformational Flexibility of Protein Molecules and the Temperature Ecology of a Species.- 5.1 Activation Energy.- 5.2 Affinity of Enzymes to Substrates, the Michaelis Constant.- 5.3 A Temperature Optimum for Enzyme Activity.- Summary.- 5.4 Lifetime of Proteins in the Cell.-Summary.- 6. Plausible Mechanisms of Regulation of the Level of Conformational Flexibility of Proteins.- 6.1 Modificational Changes of the Conformational Flexibility of Protein Macromolecules.- 6.2 Genotypic Changes of the Conformational Flexibility of Protein Molecules.- 7. Thermostability of Nucleic Acids and the Temperature Environment of Species' Life.- Summary.- 8. Saturation of Fatty Acids and the Temperature Conditions of Life.- Summary.- Epilogue.- References.