When you see Bacteroides, immediately think "gut anaerobe." They are the dominant Gram-negative anaerobes in the human colon, and their claim to fame is digesting the complex carbs (fiber) in our diet.
Anaerobic, gram-negative, nonspore-forming rods and usually nonmotile.
Not able to degrade cellulose, pectins, and other complex carbohydrates.
Hide Solution
Verified By Collegedunia
The Correct Option isC
Solution and Explanation
Step 1: Understanding the Concept:
The question asks for the correct description of bacteria belonging to the genus Bacteroides. These bacteria are a major component of the mammalian gut microbiota. Step 2: Detailed Explanation:
Let's evaluate each description:
(A) Chemoautotrophs, aerobic and gram positive: This is incorrect on all counts. Bacteroides are chemoheterotrophs, obligate anaerobes, and are Gram-negative.
(B) Causative agents of Lyme diseases: This is incorrect. Lyme disease is caused by the spirochete Borrelia burgdorferi.
(C) Anaerobic, gram-negative, nonspore-forming rods and usually nonmotile: This is the correct textbook description of the genus Bacteroides. They thrive in the anaerobic environment of the large intestine.
(D) Not able to degrade cellulose, pectins, and other complex carbohydrates: This is incorrect. In fact, the opposite is true. Bacteroides are renowned for their extensive repertoire of enzymes that allow them to ferment and degrade complex plant polysaccharides that are indigestible by humans. This is their key ecological role in the gut.
Step 3: Final Answer:
The most accurate description of organisms from the genus Bacteroides is given in option (C).
