Facultative anaerobe

Definition

A facultative anaerobe is a microorganism that can grow with or without oxygen. It utilizes aerobic respiration when oxygen is present and switches to anaerobic methods like fermentation in its absence.

5 Must Know Facts For Your Next Test

1. Facultative anaerobes have versatile metabolic pathways, allowing them to adapt to varying oxygen levels.
2. They perform better and grow faster in the presence of oxygen due to the efficiency of aerobic respiration.
3. In anoxic conditions, they rely on fermentation or anaerobic respiration for energy production.
4. Common examples include Escherichia coli and Saccharomyces cerevisiae.
5. The ability to switch between aerobic and anaerobic metabolism allows facultative anaerobes to colonize diverse environments.

Review Questions

Related terms

Obligate Aerobe: An organism that requires oxygen for cellular respiration and cannot survive without it.

Obligate Anaerobe: An organism that cannot tolerate oxygen and relies entirely on anaerobic processes for growth.

Aerotolerant Anaerobe: An organism that does not require oxygen but can survive and grow in its presence by using fermentation exclusively.