Azotobacter

bacteria

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June 18, 2026

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Azotobacter are a genus of large, rod-shaped or spherical bacteria found in soil and sewage. These bacteria are significant because they are capable of fixing atmospheric nitrogen, converting it into a form usable by plants. This process is crucial for the nitrogen cycle, as nitrogen is essential for plant growth. Azotobacter are classified as free-living, or nonsymbiotic, nitrogen-fixing bacteria, distinguishing them from symbiotic bacteria like Rhizobium that associate with specific plants.12

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bacteria
Diversity of structure of bacteria
…are relatively large, such as Azotobacter, which has diameters of 2 to 5 μm or more; and Achromatium, which has a minimum width of 5 μm and a maximum length of 100 μm, depending on the species. Giant bacteria can be visible with the unaided eye, such as Thiomargarita namibiensis,…
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…are relatively large, such as Azotobacter, which has diameters of 2 to 5 μm or more; and Achromatium, which has a minimum width of 5 μm and a maximum length of 100 μm, depending on the species. Giant bacteria can be visible with the unaided eye, such as Thiomargarita namibiensis,…
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bacteria
Sporulation
…produced by dormant members of Azotobacter, Bdellovibrio (bdellocysts), and Myxococcus (myxospores). They are resistant to desiccation and other harmful conditions but to a lesser degree than are endospores. In encystment by the nitrogen-fixing Azotobacter, cell division is followed by the formation of a thick, multilayered wall and coat that surround…
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…produced by dormant members of Azotobacter, Bdellovibrio (bdellocysts), and Myxococcus (myxospores). They are resistant to desiccation and other harmful conditions but to a lesser degree than are endospores. In encystment by the nitrogen-fixing Azotobacter, cell division is followed by the formation of a thick, multilayered wall and coat that surround…
Read More