Prescott’s Microbiology

Book Preface

In February 2012, the National Aeronautics and Space Administration (NASA) reported that over 2,000 potential planets had been discovered by the 2009 Kepler mission. Using a telescope in space, the light emanating from stars as far as 3,000 light-years away had been monitored every half-hour. The Kepler telescope identified planets as they circulated their star and caused a brief decrease in emitted light; just as an object is detected as a blip by radar, a blip of “darkness” indicates a planet.

Unless you are a science fiction fan, you might wonder why NASA is interested in finding planets. By finding other planets, scientists can gather evidence to support or refute current models of planet formation. These models predict a process that is chaotic and violent. Planets are thought to begin as dust particles circling around newly formed stars. As these particles collide, they grow in size, forming larger chunks. Eventually a series of such collisions results in planet-sized bodies. Astrobiologists are interested in identifying characteristics of a planet that may allow it to support life. Using Earth as a model, they hypothesize that life-supporting planets will share many features with Earth. But how will life be recognized? Again, scientists look to life on Earth to answer this question, and increasingly they are turning to microbiologists for help.

Earth formed 4.5 billion years ago. Within the next billion years, the first cellular life forms-microbes-appeared. Since that time, microorganisms have evolved and diversified to occupy virtually every habitat on Earth: from oceanic geothermal vents to the coldest Arctic ice. The diversity of cellular microorganisms is best exemplified by their metabolic capabilities. Some carry out respiration, just as animals do. Others perform photosynthesis, rivaling plants in the amount of carbon dioxide they capture, forming organic matter and releasing oxygen into the atmosphere. Indeed, Prochlorococcus, a cyanobacterium (formerly called a blue-green alga), is thought to be the most abundant photosynthetic organism on Earth and Artist’s rendition of the six planets orbiting a star called Kepler-11. The drawing is based on observations made of the system by the Kepler spacecraft on August 26,2010. Some are Earth-sized and may be habitable by life. thus a major contributor to the functioning of the biosphere. In addition to these familiar types of metabolism, other microbes are able to use inorganic molecules as sources of energy in both oxic (oxygen available) and anoxic (no oxygen) conditions. It is these microbes that are of particular interest to NASA scientists, as it is thought that the organisms on other planets may have similar unusual metabolisms.

Our goal in this chapter is to introduce you to this amazing group of organisms and to outline the history of their evolution and discovery. Microbiology is a biological science, and as such, much of what you will learn in this text is similar to what you have learned in high school and college biology classes that focus on large organisms. But microbes have unique properties, so microbiology has unique approaches to understanding them. These too will be introduced. But before you delve into this chapter, check to see if you have the background needed to get the most from it. Readiness Check:

Based on what you have learned previously, you should be able to:

• List the features of eukaryotic cells that distinguish them from other cell types
• List the attributes that scientists use to determine if an object is alive

Brief Contents

About the Authors iii
Preface iv
Part One Introduction to Microbiology
1 The Evolution of Microorganisms and Microbiology
2 Microscopy 22
3 Bacterial Cell Structure 42
4 Archaeal Cell Structure 82
5 Eukaryotic Cell Structure 92
6 Viruses and Other Acellular Infectious Agents 112
Part Two Microbial Nutrition, Growth, and Control
7 Microbial Growth 133
8 Control of Microorganisms in the Environment 172
9 Antimicrobial Chemotherapy 189
Part Three Microbial Metabolism
10 Introduction to Metabolism 210
11 Catabolism: Energy Release and Conservation 230
12 Anabolism: The Use of Energy in Biosynthesis 266
Part Four Microbial Molecular Biology and Genetics
13 Bacterial Genome Replication and Expression 287
14 Regulation of Bacterial Cellular Processes 325
15 Eukaryotic and Archaeal Genome Replication and Expression 353
16 Mechanisms of Genetic Variation 372
17 Recombinant DNA Technology 404
18 Microbial Genomics 424
Part Five The Diversity of the Microbial World
19 Microbial Taxonomy and the Evolution of Diversity 447
20 The Archaea 469
21 The Deinococci, Mollicutes, and Nonproteobacterial Gram-Negative Bacteria 489
22 The Proteobacteria 509
23 Firmicutes: The Low G + C Gram-Positive Bacteria 542
24 Actinobacteria: The High G + C Gram-Positive Bacteria 555
25 The Protists 568
26 The Fungi (Eumycota) 588
27 Viruses 604
Part Six Ecology and Symbiosis
28 Biogeochemical Cycling and Global Climate Change 632
29 Methods in Microbial Ecology 646
30 Microorganisms in Marine and Freshwater Ecosystems 660
31 Microorganisms in Terrestrial Ecosystems 679
32 Microbiallnteractions 699
Part Seven Pathogenicity and Host Response
33 Innate Host Resistance 723
34 Adaptive Immunity 753
35 Pathogenicity and Infection 789
Part Eight Microbial Diseases, Detection, and Their Control
36 Clinical Microbiology and Immunology 808
37 Epidemiology and Public Health Microbiology
38 Human Diseases Caused by Viruses and Prions
39 Human Diseases Caused by Bacteria 888
40 Human Diseases Caused by Fungi and Protists
Part Nine Applied Microbiology
41 Microbiology of Food 958
42 Biotechnology and Industrial Microbiology 979
43 Applied Environmental Microbiology 996
Appendix 1 A Review of the Chemistry of Biological Molecules A-1
Appendix 2 Common Metabolic Pathways A-9
Glossary G-1
Credits C-1
Index 1-1