Biochemistry - The Chemical Reactions of Living Cells, Volume 1 - D. Metzler 1980

The Theater of Action
Simple Living Organisms
Classification of Bacteria

Bacteria exhibit extreme diversity in Chemical Composition and metabolic pathways, making The Development of a rational Classification system highly challenging. For higher organisms, METABOLISM/2.html">THE CONCEPT OF "species" can be defined as non-interbreeding forms; however, this criterion is meaningless for bacteria, rendering their division into species and genera often arbitrary. The currently employed scheme (Table 1-1) divides the prokaryotic kingdom into 19 groups, based on various characteristics including Morphology, staining properties, and chemical traits. The table includes the generic names of all bacteria mentioned in the text of this book.

Bacteria take the form of spheres or rods—either straight or curved. Some of them (such as actinomycetes) grow as branching, filamentous structures.

Bacterial names often reflect their morphology: coccus denotes a sphere, bacillus a rod, and vibrio a curved rod with a flagellum at one end. The term spirillum refers to helically twisted bacteria with a tuft of flagella at one or both poles. Overall, the classification of bacteria remains an unresolved issue, as identical names are frequently used for both individual species and families. A number of names reflect specific Chemical properties of the bacteria being described.



Last update: 06/08/2026

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