Comparative Virology

Karl Maramorosch, Edouard Kurstak

• Publisher: Academic Press
• Year: 2014
• ISBN:
  9781483269696
• Topic: Biological Sciences
• Subtopic: Evolution
• Index: Biological Sciences

Comparative Virology provides an integrated comparison of viruses, based on their chemical and morphological characteristics. These descriptions will not only give the reader a background but also a detailed analysis of the various groups. In some instances the groups are still host related, as in the case of bacteriophages and polyhedral insect viruses. In others, for instance in pox viruses, the group comprises viruses of vertebrates and invertebrates. The hosts of the bacilliform Rhabdovirales range from man and other warm-blooded vertebrates through invertebrate animals to plants. A special chapter is devoted to viruses devoid of protein—a group that is of great interest and that has only recently been recognized. Since there is historical and practical interest in écologie groupings, such as arboviruses and oncogenic viruses, chapters on such groups have also been included. The book opens with a discussion on the classification of viruses. Chapters dealing with DNA viruses and RNA viruses follow, and the ecologically and disease-oriented groups complete the volume. It is hoped that ""Comparative Virology"" will help bring unity to the science of virology through the comparative approach that is not dependent on virus-host interactions. The combined efforts of eminent contributors to discuss and evaluate new information will hopefully benefit all who are interested in virology

CHAPTER 1

Remarks on the Classification of Viruses

ANDRÉ LWOFF and PAUL TOURNIER

Publisher Summary

This chapter presents remarks on viruses, phanerogram, cryptogram, and gymnogram. It discusses various characteristics of the families of viruses. Viruses are defined by the sum of the distinctive traits of the virion. These distinctive traits are as follows: (1) presence of a single nucleic acid; (2) incapacity to grow and to divide; (3) reproduction from the genetic material only; (4) absence of enzymes for energy metabolism; (5) absence of ribosomes; (6) absence of information for the production of enzymes in the energy cycle; (7) absence of information for the synthesis of the ribosomal proteins; and (8) absence of information for the synthesis of ribosomal RNA and transfer RNA. The viral infectious particle presents a great diversity in composition and structure. Order could be achieved only through a classification, which is a system of order. The goal of biological classification is to group together organisms presenting certain analogies and certain affinities and, if possible, to also bring out phylogenic relationships. The conceptions relative to the methodology of taxonomy, which is the science of classification, are diverse. A virus may have evolved from a given sector of DNA within the host cell. It could also very well have derived from the corresponding RNA messenger that contains the same information, both qualitatively and quantitatively. Therefore, theoretically, different viruses could have originated from nucleic acids of different but complementary nature. The nucleic acid of viruses is either single- or double-stranded. Viruses, as is generally accepted, derive from the nucleic acid of their host. Thus, RNA viruses could possibly have their origin in the RNA messenger.

To know, is to classify.

Stuart Mill

The coining and application of any collective or generic term represents an act of classification.

Ernst Mayr

I Introduction

II The LHT system

A The System

B Discussion

C Remarks on Viruses without Capsid

III Prons and Cons of the LHT System

A Pros

B Cons

IV Phanerogram, Cryptogram, and Gymnogram

A Phanerogram

B Cryptogram

C Comparative Values of the Characteristics of the Phanerogram and the Cryptogram

D Other Characters of the Cryptogram

E General Remarks

F Gymnogram

V Evaluation of Characteristics

VI Categories and Taxons; Nomenclature

A Names, Categories, Taxons

B Remarks on the Term “Group”

C Rules of Nomenclature

D Classification and Nomenclature

E Opposition to Binominal Nomenclature

F Competence of International Committees for Nomenclature

VII Lanni’s System

VIII Bellett’s System

A The System

B Nucleic Acids versus Capsids: Uroviruses

IX Miscellaneous Remarks

A Symmetry

B RNA and DNA Viruses

C Single- and Double-Stranded Viruses

D The Frequency of the Doublet Patterns

E Doublet Frequency and Selection

X Gibb’s Classification

XI The Classification of the Classifications

XII Conclusions

References

I Introduction

Only a few years ago, the viral world was a chaos of “small infectious particles.” Consequently, it embraced, at the same time, viruses and bacteria. Today, the viruses are well defined by the sum of the distinctive traits of the virion. These distinctive traits are as follows:

1. Presence of a single nucleic acid.

2. Incapacity to grow and to divide.

3. Reproduction from the genetic material only.

4. Absence of enzymes for energy metabolism.

5. Absence of ribosomes.

6. Absence of information for the production of enzymes in the energy cycle.

7. Absence of information for the synthesis of the ribosomal proteins.

8. Absence of information for the synthesis of ribosomal RNA and transfer RNA.

It would appear that a correlation exists among all these characteristics: only one of them is, in fact, sufficient to establish that an infectious particle belongs to the viral world. In the group of viruses recognized as such by the virtue of a definition, it became evident that order was mandatory.

In fact, the remarkable homogeneity, attested to by the number and extent of the common characteristics, masks a no less remarkable diversity. The viral infectious particle presents, in fact, a great diversity in composition and structure. Order could be achieved only through a classification, which is a system of order. The goal of biological classification is to group together organisms presenting certain analogies and certain affinities and, if possible, to also bring out phylogeni...

Table of contents

• Cover image
• Title page
• Table of Contents
• CONTRIBUTORS
• Copyright
• List of Contributors
• Preface
• Chapter 1: Remarks on the Classification of Viruses
• Chapter 2: Small DNA Viruses
• Chapter 3: The Papovavirus Group
• Chapter 4: Adenoviruses
• Chapter 5: Herpesviruses: Current Information on the Composition and Structure
• Chapter 6: Comparative Observations on Poxviruses of Invertebrates and Vertebrates
• Chapter 7: A Comparative Study of the Structure and Biological Properties of Bacteriophages
• Chapter 8: Picornaviral Architecture
• Chapter 9: Arboviruses: Incorporation in a General System of Virus Classification
• Chapter 10: Comparative Properties of Rod-Shaped Viruses
• Chapter 11: Bullet-Shaped Viruses
• Chapter 12: Structure and Transcription of the Genomes of Double-Stranded RNA Viruses
• Chapter 13: The Structure and Assembly of Influenza and Parainfluenza Viruses
• Chapter 14: A Plant Virus with Properties of a Free Ribonucleic Acid: Potato Spindle Tuber Virus
• Chapter 15: The Viruses Causing the Polyhedroses and Granuloses of Insects
• Chapter 16: Oncogenic Viruses: A Survey of Their Properties
• Author Index
• Subject Index