Chatper 19 : Taxonomic Overview

Abstract:

Taxonomy of many proteobacteria, protists, and fungi is in flux, and a “tree of life” is a continuous “construction site”. This chapter talks about prions, viruses, bacteria, protists, fungi, and helminths. Prions are misfolded, transmissible proteins that withstand ordinary heat treatment. Hosts, histopathology, and proteomics are used to define phenotypes. Viruses are biochemical units characterized by a core from nucleic acid (RNA or DNA) and a shell from protein, without or with an envelope. Taxonomy uses hosts, cytopathology, ultrastructure, genomics, phylogeny, and response to antivirals such as nucleoside antagonists, enzyme inhibitors, and interferon-a. Taxonomy uses hosts, in vitro growth and metabolism, staining and morphology, genomics, phylogeny, and response to antimycobacterials and antibiotics such as β-lactams, macrolides, quinolones, and aminoglycosides. Taxonomy uses growth on substrates, reproduction, ultrastructure, genomics, phylogeny, and response to antifungals such as triazoles, amphotericin B, and terbinafine.