Obligate (strict) aerobe

Definition

An obligate (strict) aerobe is an organism that requires oxygen for cellular respiration and cannot grow without it. These microorganisms utilize oxygen as the terminal electron acceptor in their metabolic processes.

5 Must Know Facts For Your Next Test

1. Obligate aerobes are found in environments where oxygen is plentiful, such as the surface of soil and water.
2. They generate energy through aerobic respiration, which produces more ATP compared to anaerobic pathways.
3. Common examples of obligate aerobes include Mycobacterium tuberculosis and Pseudomonas aeruginosa.
4. Growth of obligate aerobes is inhibited or halted in the absence of oxygen due to their inability to perform fermentation or anaerobic respiration.
5. They possess enzymes like superoxide dismutase and catalase that protect them from toxic forms of oxygen.

Review Questions

Related terms

Facultative Anaerobe: An organism that can grow with or without oxygen by switching between aerobic and anaerobic metabolism.

Microaerophile: An organism that requires lower levels of oxygen than are present in the atmosphere for optimal growth.

Anaerobe: An organism that does not require oxygen for growth and may even die in its presence.