Question

Match List I with List II
List I (Antibiotics): A. Bacitracin, B. Colicine, C. Gramicidin, D. Polymyxin
List II (Microorganism): I. Bacillus polymyxa, II. Bacillus brevis, III. Bacillus subtilis, IV. E. coli

• A. A‐III, B‐IV, C‐I, D‐II
• B. A‐III, B‐ IV, C‐II, D‐I
• C. A‐IV, B‐III, C‐I, D‐II
• D. A‐III, B‐I, C‐IV, D‐II

Hint:

Mnemonic for antibiotics:
- Polymyxin = Polymyxa.
- Colicine = E. coli.
- Gramicidin = B. brevis (think of short "brief" Brevis).
- Bacitracin = B. subtilis.

Answer 1

The Correct Option is B

Step 1: Understanding the Question:
The question requires matching various antibiotics with the specific bacterial species that produce them. Many important antibiotics are secondary metabolites of soil bacteria.

Step 2: Detailed Explanation:

• Bacitracin (A): Produced by the Bacillus subtilis group (specifically Bacillus licheniformis). It is used in topical ointments. Thus, A matches with III.

• Colicine (B): These are bacteriocins produced by Escherichia coli (IV) to kill closely related bacterial strains. Thus, B matches with IV.

• Gramicidin (C): This is a heterogeneous mixture of antibiotic compounds produced by Bacillus brevis (II). It is effective against Gram-positive bacteria. Thus, C matches with II.

• Polymyxin (D): As the name suggests, it is produced by Bacillus polymyxa (I). It is used to treat Gram-negative infections. Thus, D matches with I.

• Assembly: A-III, B-IV, C-II, D-I. This corresponds to Option (B).

Step 3: Final Answer:
The correct matching sequence is A-III, B-IV, C-II, D-I.