Thermophilic Bacteria

Jakob K. Kristjansson

• Publisher: CRC Press
• Year: 2021
• Print ISBN: 9780849352393
• eBook ISBN: 9781000141696
• Edition: 1
• Topic: Biological Sciences
• Subtopic: Biology
• Index: Biological Sciences

Thermophilic Bacteria is a comprehensive volume that describes all major bacterial groups that can grow above 60-65°C (excluding the Archaea). Over 60 different species of aerobic and anaerobic thermophilic bacteria are covered. Isolation, growth methods, characterization and identification, ecology, metabolism, and enzymology of thermophilic bacteria are examined in detail, and an extensive compilation of recent biotechnological applications and the properties of many thermostable enzymes are also included.Major topics discussed in the book include a general review on thermophilic bacteria and archaea; heterotropic bacilli; the genus Thermus; new and rare genera of aerobic heterophophs, such as Saccharococcus, Rhodothermus, and Scotohermus; aerobic chemolithoautotrophic thermophilic bacteria; obligately anaerobic thermophilic bacteria; and hyperthermophilic Thermotogales and thermophilic phototrophs. Extensive bibliographies are also provided for each chapter. The vast amount of information packed into this one volume makes it essential for all microbiologists, biochemists, molecular biologists, and students interested in the expanding field of thermophilicity. Biotechnologists will find the book useful as a source of information on thermophiles or thermostable enzymes of possible industrial use.

Chapter 1

THERMOPHILIC BACTERIA

Jakob K. Kristjansson and Karl O. Stetter

TABLE OF CONTENTS

I. Introduction

II. Definitions and Terminology

III. Characteristics of Thermophiles

A. Archaea

B. Bacteria

IV. Ecology of Thermophiles

A. Geothermal Habitats

B. Other Thermal Habitats

C. Ecology of Thermophilic Archaea

D. Ecology of Thermophilic Bacteria

E. Diversity of Thermophiles

V. The Evolution of Thermophiles

A. Phylogeny of Thermophiles

B. Thermophiles and Geochemical History

VI. Conclusions

Acknowledgments

References

I. INTRODUCTION

Thermophilic microorganisms have been known for a long time but usually considered as some sort of biological eccentrics. Thermostable microbes and spores have previously been looked at as pests in the food processing and canning industry. In the past we generally learned that living organisms and also their individual components such as proteins are killed or denatured by heating. It is, therefore, very difficult to comprehend that some organisms do not only survive at high temperatures, but actually thrive in boiling water.^1,2

The possible exploitation of the thermostable properties of thermophiles has been recognized for some time but has only recently really started to be realized in industry.^3,4,5

Many enzymatic or microbiological industrial processes are already run at a high temperature and those that are not could, in many cases, benefit from increased heating if not prevented by some unstable components in the process. The main advantages of increased temperature are generally higher reaction rates, higher solubility of most chemicals, and increased fluidity and diffusion rates. The early notion that high temperature prevents microbial contamination is only partly correct. It does, in fact, prevent growth of most environmental mesophilic microorganisms and pathogens but thermophilic microbes, especially spore formers, are surprisingly common contaminants in many processes which are run at an elevated temperature.^4,6

The main interest in thermophiles in recent years has been on two fronts. On the scientific front has been the discovery of many new extremely thermophilic archaea, some of which can grow at 100°C and even above.² On the biotechnological front has been the realization that thermophilic microorganisms can serve as excellent sources for more thermostable biocatalysts than are presently available.^4,7 More stable biocatalysts can open up many new possibilities that were not known before, for example, in bioorganic synthesis and in biosensors.

The discovery of archaea as a third domain of life in addition to eucarya and bacteria (previously named archaebacteria, eubacteria, and eucaryotes) was a major scientific happening,^8,8a It came at a time when scientific microbiology was going through a slowly evolving period. The scientific community had the general feeling that all major scientific discoveries had already been made and that the time of great exploring missions was really over. This discovery, therefore, created a sensation in biological science, especially among microbiologists.

The discovery of several new extremely thermophilic and hyperthermophilic bacteria during the last few years, and the fact that almost all of them belonged to the archaea made the area even more exciting.^8a In view of this, it is not surprising that thermophilic archaea have received much attention in the last few years and that thermophilic bacteria have been overshadowed.

Considerable research work on thermophilic bacteria is still going on, and several new groups have also been discovered a...

Table of contents

• Cover
• Title Page
• Copyright Page
• Preface
• The Editor
• Contributors
• Table of Contents
• Chapter 1 Thermophilic Bacteria
• Chapter 2 Heterotrophic Thermophilic Bacilli
• Chapter 3 The Genus Thermos
• Chapter 4 The Heterotrophic, Thermophilic Genera Thermomicrobium, Rhodothermus, Saccharococcus. Acidothermus, and Scotothermus
• Chapter 5 The Aerobic, Chemolithoautotrophic, Thermophilic Bacteria
• Chapter 6 The Anaerobic Thermophilic Bacteria
• Chapter 7 The Thermotogales: Hyperthermophilic and Extremely Thermophilic Bacteria
• Chapter 8 Thermophilic Phototrophs
• Index