Which of the following is a bile-tolerant anaerobe?
a. Bacteroides
b. Escherichia
c. Shigella
d. Prevotella

Verified step by step guidance

1. Identify the characteristics of bile-tolerant anaerobes, which are bacteria that can survive in environments with bile and do not require oxygen for growth.
2. Review the list of bacteria provided in the options: Bacteroides, Escherichia, Shigella, and Prevotella.
3. Consider the typical environments where these bacteria are found. Bile-tolerant anaerobes are often found in the gastrointestinal tract where bile is present.
4. Recall that Bacteroides and Prevotella are known to be part of the gut microbiota and are anaerobic, meaning they can grow without oxygen.
5. Determine which of these bacteria are known to be bile-tolerant anaerobes based on their ability to thrive in the gut environment.

Key Concepts

Bile Tolerance

Bile tolerance refers to the ability of certain bacteria to survive and grow in the presence of bile salts, which are components of bile produced by the liver. This characteristic is crucial for bacteria that inhabit the gastrointestinal tract, as bile can inhibit the growth of many microorganisms. Bile-tolerant anaerobes can thrive in environments where bile is present, making them significant in gut microbiota.

Anaerobic Bacteria

Anaerobic bacteria are microorganisms that do not require oxygen for growth and may even be harmed by its presence. These bacteria can be found in various environments, including the human gut, where they play essential roles in digestion and maintaining a balanced microbiome. Understanding anaerobic metabolism is key to identifying and classifying these organisms.

Genus Identification

Genus identification involves classifying bacteria into groups based on shared characteristics, such as morphology, genetic makeup, and metabolic capabilities. In the context of the question, recognizing which genera (like Bacteroides, Escherichia, Shigella, and Prevotella) contain bile-tolerant anaerobes is essential for selecting the correct answer. This classification helps in understanding the ecological roles and clinical significance of these bacteria.