Basicmedical Key

20.1 INTRODUCTION TO BACTERIAL VIRUSES (BACTERIOPHAGES) Bacterial viruses, known as bacteriophages or phages (from the Greek phagein, “to eat”), were discovered independently by Frederick Twort (1915) and Felix d’Herelle (1917)….

19.1 INTRODUCTION TO HEPADNAVIRUSES The hepadnaviruses got their name because they cause hepatitis and they have DNA genomes. They are known as hepatitis B viruses (HBVs) and are classified in…

14.1 INTRODUCTION TO PICORNAVIRUSES Members of the family Picornaviridae are found in mammals and birds. These viruses have features in common with many plant viruses, and are classified with them…

15.1 INTRODUCTION TO RHABDOVIRUSES The rhabdoviruses have minus-strand RNA genomes in the size range 11–15 kb. The name of these viruses is derived from the Greek rhabdos, which means a…

22.1 INTRODUCTION TO EMERGING VIRUSES The term “emerging virus” is used in a number of contexts: it may refer to a virus that has recently made its presence felt by…

18.1 INTRODUCTION TO HIV There are two types of human immunodeficiency virus (HIV-1 and HIV-2), which each evolved from a different simian immunodeficiency virus (SIV). Both HIVs emerged in the…

17.1 INTRODUCTION TO RETROVIRUSES The retroviruses are RNA viruses that copy their genomes into DNA during their replication. Until the discovery of these viruses it had been dogma that the…

11.1 INTRODUCTION TO HERPESVIRUSES The word herpesvirus is derived from the Greek herpein, meaning to creep. More than 100 herpesviruses have been isolated and classified in the order Herpesvirales. Those…

21.1 INTRODUCTION TO ORIGINS AND EVOLUTION OF VIRUSES In this chapter we shall speculate on how viruses may have originated and consider the mechanisms by which viruses evolved in the…

6.1 INTRODUCTION TO TRANSCRIPTION, TRANSLATION, AND TRANSPORT In this chapter we deal with three terms derived from the Latin trans, meaning across. For our purposes, transcription refers to the writing…