General Microbiology - Schlegel, H. 1987

Prokaryotes: A Systematic Review
Taxonomy: A Review of the Prokaryotic System

The taxonomy is based on the Classification of Bacteria into morphologically distinct forms that are easily distinguishable under a Microscope (cocci, bacilli, spirilla), Gram staining, and their relationship to molecular oxygen (aerobes, anaerobes), referencing the 19 groups of bacteria outlined in Bergey's Manual of Determinative Bacteriology (8th edition, 1974). Cyanobacteria were added as the 20th group.

1. Cocci — spherical bacteria

A. Gram-positive cocci

Aerobic

Group 14. Gram-Positive Cocci

Micrococcus, Staphylococcus, Streptococcus, Leuconostoc, Pediococcus

Anaerobic

Peptococcus, Peptostreptococcus, Ruminococcus, Sarcina

B. Gram-negative cocci

Aerobic

Group 10. Gram-Negative Cocci and Coccobacilli

Neisseria, Moraxella, Acinetobacter, Paracoccus, Lampropedia

Anaerobic

Group 11. Gram-Negative Cocci

Veillonella, Acidaminococcus, Megasphaera

2. Bacilli — elongated cylindrical bacteria

A. Gram-positive bacteria

Aerobic

Group 16. Gram-Positive Asporogenous Rods

Lactobacillus, Listeria, Erysipelothrix Caryophanon

Aerobic

Group 17. Coryneform Bacteria and Actinomycetes

Corynebacterium, Arthrobacter, Brevibacterium, Cellulomo- nas, Rhodococcus, Propionibacterium, Eubacterium

Bifidobacterium, Mycobacterium, Nocardia

Actinomyces, Franckia, Actinoplanes, Dermatophilus, Micro- monospora, Microbispora, Streptomyces, Streptosporangium

Aerobic

Group 15. Endospore-Forming Rods and Cocci

Bacillus, Sporolactobacillus, Sporosarcina, Thermoactinomy- ces

Anaerobic

Clostridium, Desulfotomaculum, Oscillospira

B. Gram-negative bacteria

Aerobic

Group 7. Gram-Negative Aerobic Rods and Cocci

Pseudomonas, Xanthomonas, Zoogloea, Gluconobacter,

Acetobacter

Azotobacter, Azomonas, Beijerinckia, Derxia

Rhizobium, Agrobacterium, Alcaligenes

Brucella, Legionella, Thermus

Aerobic

Group 12. Gram-Negative Aerobic Chemolithotrophic Bacteria

Nitrobacter, Nitrospina, Nitrococcus, Nitrosomonas, Nitrosospira, Nitrosococcus, Nitrosolobus

Thiobacillus, Sulfolobus1, Thiobacterium, Thiovulum.

Aerobic

Group 3. Chlamydobacteria

Sphaerotilus, Leptothrix; Streptothrix, Crenothrix

Facultatively anaerobic

Group 8. Gram-Negative Facultatively Anaerobic Rods

Escherichia, Klebsiella, Enterobacter, Salmonella, Shigella, Proteus, Serratia, Erwinia

Yersinia

Vibrio, Aeromonas, Photobacterium

Strictly anaerobic

Group 9. Gram-Negative Anaerobic Bacteria

Bacteroides, Fusobacterium, Leptotrichia

Strictly anaerobic

Group 13. Methane-Producing and Other Archaebacteria

Methanobacterium (G+)1, Methanothermus (G+), Methanosarcina (G+), Metanothrix, Methanococcus

Aerobic

Halobacterium, Halocоccus (G+), Sulfolobus, Thermoplasma

Anaerobic

Thermoproteus, Pyrodictium, Desulfurococcus

1 According to modern data, Sulfolobus belongs to archaea. Ed. note.

3. Curved Rods or flexible Cells

Aerobic

Group 6. Gram-Negative Spiral and Curved Bacteria

Spirillum, Aquaspirillum, Azospirillum, Oceanospirillum, Campylobacter

Bdellovibrio, Microcyclus, Pelosigma

Anaerobic

Group 9. Gram-Negative Curved Anaerobic Bacteria

Desulfovibrio

Succinivibrio, Butyrivibrio

Selenomonas

Aerobic and anaerobic

Group 5. Spirochetes

Spirochaeta, Cristispira, Treponema, Borrelia, Leptospira

4. Major distinct groups

Group 2. Gliding Bacteria (all Gram-negative)

Myxococcus, Archangium, Cystobacter, Melittangium, Stigmatella, Polyangium, Nannocystis, Chondromyces

Cytophaga, Sporocytophaga, Flexibacter, Herpetosiphon, Saprospira

Beggiatoa, Thiothrix, Thioploca, Achromatium, Leucothrix,

Vitreoscilla

Simonsiella, Alysiella

Group 4. Budding and Appendaged Bacteria

Нyphomicrobium, Hyphomonas

Caulobacter, Asticcacaulis, Planctomvces

1 (G+) Gram-positive staining.

Ancalomicrobium, Prosthecomicrobium, Metallogenium, Blastobacter, Seliberia, Gallionella, Nevskia

Group 18. Obligately Parasitic Bacteria: Rickettsiae and Chlamydiae

Rikkettsia, Coxiella, Chlamydia

Group 19. Mycoplasma Group (Mollicutes)

Mycoplasma, Acholeplasma, Spiroplasma

Group 1. Anaerobic anoxygenic phototrophic Bacteria

Rhodospirillum, Rhodopseudomonas, Rhodomicrobium1

Chromatium, Thiocystis, Thiosarcina, Thiocapsa, Thiospirillum, Thiopedia, Amoebobacter, Ectothiorhodospira,

Lamprocystis, Thiodictyon

Chlorobium, Prosthecochloris, Pelodictyon, Chloroherpeton

Chloroflexus

Group 20. Aerobic Oxygenic Phototrophic Bacteria: Cyanobacteria (Blue-Green Algae)

Synechococcus, Gloeocapsa, Gloeothece, Gloeobacter

Pleurocapsa, Dermocarpa, Myxosarcina

Oscillatoria, Spirulina, Lyngbya, Phormidium, Plectonema

Anabaena, Nostoc, Calothrix, Fischerella



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