Obligate anaerobes

Definition

Obligate anaerobes are organisms that cannot survive in the presence of oxygen. They obtain energy through anaerobic processes, such as fermentation or anaerobic respiration.

5 Must Know Facts For Your Next Test

1. Obligate anaerobes thrive in environments devoid of oxygen.
2. Fungi can include obligate anaerobes, particularly within soil and aquatic habitats where oxygen is limited.
3. These organisms typically utilize fermentation to generate energy in the absence of oxygen.
4. Exposure to oxygen can be toxic for obligate anaerobes, leading to their death.
5. Clostridium, a genus containing several obligate anaerobe species, is an example found in both bacteria and fungal contexts.

Review Questions

• What environments do obligate anaerobes primarily thrive in?
• How do obligate anaerobes generate energy without oxygen?
• Why is exposure to oxygen detrimental for obligate anaerobes?

Related terms

Facultative Anaerobes:

Organisms that can survive with or without oxygen by switching between aerobic and anaerobic metabolism.

Aerotolerant Anaerobes: Microorganisms that tolerate the presence of oxygen but do not use it for growth.

Fermentation: A metabolic process that converts sugar to acids, gases, or alcohol in the absence of oxygen.