Nonproteobacteria

Definition

Nonproteobacteria are a diverse group of Gram-negative bacteria that do not belong to the Proteobacteria phylum. They include many different lineages with various metabolic capabilities and ecological roles.

5 Must Know Facts For Your Next Test

1. Nonproteobacteria include important groups such as Cyanobacteria, Chlorobi, and Spirochaetes.
2. Cyanobacteria are known for their role in oxygenic photosynthesis and can form harmful algal blooms.
3. Chlorobi, or green sulfur bacteria, perform anoxygenic photosynthesis using sulfur compounds as electron donors.
4. Spirochaetes have a distinctive helical shape and include pathogens like Treponema pallidum, which causes syphilis.
5. Many nonproteobacteria are extremophiles, thriving in environments with extreme temperatures, salinity, or pH.

Review Questions

• What is a defining characteristic of Nonproteobacteria?
• Name two groups within Nonproteobacteria and describe their metabolic processes.
• Why are Cyanobacteria ecologically significant?

Related terms

Proteobacteria:

A major phylum of Gram-negative bacteria including many well-known pathogens.

Oxygenic Photosynthesis: A process by which organisms use light energy to produce oxygen from water.

Anoxygenic Photosynthesis: Photosynthesis in which light energy is captured without producing oxygen.