In 1963, the first edition of Chemistry of Viruses was published as a contribution to the series on viruses sponsored by Protoplasmatologia. An aim of the first edition was to review some major principles and techniques of chemical virology in a concise manner and to accompany this review with a compilation of pertinent references. It was anticipated that this exercise would be helpful to the author in his teaching and research and, hopefully, would be useful to readers as well. The literature of virology has grown enormously since then, and it is even more urgent to have a succinct survey. In addition, few authors have attempted to integrate the findings pertaining to the various major classes of viruses (that is, animal, bacterial, and plant viruses) but, rather, have chosen to assemble large monographs dealing in depth with facts and fancies pertaining to specific groups of viruses. Such works are valuable for pursuit of particular topics but fail to yield a brief, integrated view of virology. The present edition of Chemistry of Viruses aspires to such a review. A serious attempt was made to deal concisely with every major topic of chemical virology and to present examples from different classes of viruses. Numerous references are given to original articles and review papers as well as to selected books.
I. Some Events Leading to the Chemical Era of Virology.- II. Purification of Viruses.- A. Some General Principles.- 1. Centrifugation.- a. Differential Centrifugation.- b. Density-Gradient Centrifugation.- 2. Enzymatic Treatment.- 3. Extraction with Organic Solvents.- 4. Precipitation Methods.- 5. Adsorption Methods.- 6. Serological Methods.- 7. Electrophoresis.- 8. Partition in Liquid Two-Phase Systems.- 9. Criteria of Purity.- III. Composition of Viruses.- A. Proteins.- 1. Preparation of Viral Proteins.- a. The Mild Alkali Method.- b. The Cold 67 Percent Acetic Acid Method.- c. The Guanidine Hydrochloride Method.- d. The Warm Salt Method.- e. The Cold Salt Method.- f. The Phenol Method.- g. The Detergent Method and General Conclusions.- 2. Analysis of Viral Proteins.- a. Amino Acid Analyses.- b. Protein End Groups.- c. Protein Subunits.- d. Amino Acid Sequences.- 3. Function of Viral Proteins.- B. Nucleic Acids.- 1. Preparation of Viral Nucleic Acids.- a. The Hot Salt Method.- b. Detergent Method.- c. Combined Detergent and Hot Salt Method.- d. The Phenol Method.- e. Phenol-Detergent Method.- f. Guanidine Hydrochloride Method.- g. Alkaline Method.- 2. Analysis of Viral Nucleic Acids.- a. Determination of the Base Ratios in RNA by Acid Hydrolysis and Paper Chromatography.- b. Determination of the Base Ratios in RNA by Alkaline Hydrolysis and Paper Electrophoresis.- c. Determination of the Base Ratios in DNA by Acid Hydrolysis and Paper Chromatography.- d. Determination of the Nucleotide Ratios in 32P-labeled RNA by Alkaline Hydrolysis and Column Chromatography.- e. Determination of Base Ratios in DNA from Buoyant Density and Thermal Denaturation Values.- f. Proportions of Nucleotides in Some Viral Nucleic Acids.- g. Polynucleotide End Groups and Other Structural Features.- h. Nucleotide Sequences.- i. Two Ways to Compare Nucleotide Sequences Without Sequencing: Nearest Neighbor Analysis and Hybridization.- j. Secondary and Higher Structure of Nucleic Acids.- 3. Function of Viral Nucleic Acids.- a. A Suggestive Idea from Bacterial Transformation.- b. A Hint from the Chemical Analysis of Spontaneous Mutants of Tobacco Mosaic Virus.- c. RNA Shown Essential for Plant Virus Duplication.- d. Role of DNA in Infection by T Phages.- e. Infectious Nucleic Acid from Tobacco Mosaic Virus.- C. Lipids.- 1. Preparation of Viral Lipids.- 2. Analysis of Viral Lipids.- 3. Function of Viral Lipids.- D. Carbohydrates.- 1. Preparation of Viral Carbohydrates.- 2. Analysis of Viral Carbohydrates.- 3. Function of Viral Carbohydrates.- E. Polyamines and Metals.- F. Summary: Composition of Viruses.- IV. Morphology of Viruses.- A. Nonenveloped Spheroidal Viruses.- B. Large Enveloped Spheroidal and Elongated Viruses.- C. Brick-Shaped Viruses.- D. Elongated Viruses.- E. Tailed Viruses.- F. Encapsulated Viruses.- V. Action of Chemical and Physical Agents on Viruses.- A. Inactivation of Viruses.- 1. Inactivation of Viruses by Heat.- 2. Inactivation of Viruses by Radiations.- 3. Inactivation of Viruses by Chemicals.- a. Enzymes.- b. Protein Denaturants.- c. Nitrous Acid.- d. Formaldehyde and Other Aldehydes.- e. Hydroxylamine.- f. Alkylating Agents.- g. Other Inactivating Chemicals.- h. In Vivo Inactivators of Viruses.- B. Mutation.- 1. Molecular Mechanisms of Mutation.- a. Nitrous Acid.- b. Hydroxylamine.- c. Alkylating Agents.- d. Base Analogs.- e. Intercalating Chemicals.- 2. Effect of Mutations on Viral Proteins.- 3. Gene Location.- a. Mating and Mapping.- b. Hybridization and Electron Microscopy.- c. Selective Mutagenesis.- d. Comparison of Amino Acid and Nucleotide Sequences.- VI. Reproduction of Viruses and Viral Constituents.- A. Virus Reproduction in Cells.- 1. Simple Infection.- 2. Complex or Mixed Infection.- 3. Viroids.- B. Extracellular Reproduction of Viruses and Viral Constituents.- 1. Reconstitution.- 2. Cell-free Synthesis of Viral Proteins.- 3. Cell-free Synthesis of Viral Nucleic Acids.- C. Origin of Viruses.- General References.- References.