What are the differences between a facultative and an obligate anaerobe?

Question

Accepted Answer

Basis of differentiation

Facultative anaerobe

Obligate anaerobe

Definition

Is an organism that is capable of growing and living in both aerobic and anaerobic environments

Is an organism that can only survive in an anaerobic environment in the total absence of oxygen

Types of cellular respiration

Exhibits aerobic respiration, anaerobic respiration and fermentation

Exhibits anaerobic respiration and fermentation

Effect of oxygen

Can survive in the presence and absence of molecular oxygen

Cannot survive in the presence of molecular oxygen

Presence in a culture tube

Collects at the bottom of the culture tube

Usually collects at the top of the culture tube but may also disperse throughout the culture medium

Examples

Salmonella
Streprococcus spp
Listeria
Staphylococcus spp
Escherichia coli

Clostridium
Propionibacterium 
Actinomyces
Veillonella 
Bacteroides

Basis of differentiation	Facultative anaerobe	Obligate anaerobe
Definition	Is an organism that is capable of growing and living in both aerobic and anaerobic environments	Is an organism that can only survive in an anaerobic environment in the total absence of oxygen
Types of cellular respiration	Exhibits aerobic respiration, anaerobic respiration and fermentation	Exhibits anaerobic respiration and fermentation
Effect of oxygen	Can survive in the presence and absence of molecular oxygen	Cannot survive in the presence of molecular oxygen
Presence in a culture tube	Collects at the bottom of the culture tube	Usually collects at the top of the culture tube but may also disperse throughout the culture medium
Examples	Salmonella Streprococcus spp Listeria Staphylococcus spp Escherichia coli	Clostridium Propionibacterium Actinomyces Veillonella Bacteroides