4: Redox and Mechanism
- Page ID
- 131128
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Microorganisms drive oxidation-reduction reactions (i.e., redox reactions) forward to obtain energy for life functions and to obtain nutrients needed to make biomass. Those reactions play a central role in the two-way interactions between microbes and their environments. Environments influence what redox reactions are available to the microbial community, and by driving the reactions forward, the microbes influence the geochemical evolution of the system.
Because of these relationships, understanding redox chemistry is essential to developing a strong foundation for geomicrobiology. We begin this chapter by reviewing some of the basics of redox reactions and then discuss the major categories of microbial metabolisms.
- 4.1: Redox basics
- Basic principles of redox reactions, identifying redox reactions, and rules for identifying oxidation states/oxidation numbers. Includes practice problems.
- 4.2: Balancing redox reactions
- Procedure for writing and balancing simple redox reactions. Includes worked examples and practice problems.
- 4.3: Metabolism
- Simple classification of the metabolic strategies of microorganisms, based on how they obtain energy and carbon.
- 4.4: Chemotrophy
- Division of chemotrophic metabolic reactions into catabolism and anabolism. Respiration and fermentation reactions in chemical catabolism, and how ATP is generated.
- 4.5: Phototrophy
- Metabolic reactions of oxygenic and anoxygenic photoautotrophs.