Facultative Anaerobe Bacteria Identification

A facultative anaerobe is a microorganism that can grow both in the presence of oxygen (aerobic respiration) and in the absence of oxygen (anaerobic respiration or fermentation). Understanding the oxygen requirements of different bacteria is crucial for their classification.

Bacterial Oxygen Requirements Analysis

Let's examine the oxygen requirements for each bacterium listed:

• Pseudomonas: Typically considered aerobic, meaning they require oxygen for growth.
• Bacteroides: These are obligate anaerobes, meaning they grow only in the absence of oxygen and are often killed by its presence.
• Escherichia: Commonly known as E. coli, this bacterium is a classic example of a facultative anaerobe. It can perform aerobic respiration when oxygen is present but can switch to fermentation or anaerobic respiration when oxygen is absent.
• Clostridium: These are also obligate anaerobes, similar to Bacteroides, and cannot survive in oxygenated environments.

Conclusion on Facultative Anaerobes

Based on the analysis, Escherichia is the bacterium classified as a facultative anaerobe among the given options.