Antibiotic producer identification: Chlorotetracycline (a broad-spectrum tetracycline) is industrially produced by which Streptomyces species?

Introduction / Context:
Matching antibiotics to their producer organisms is a core skill in pharmaceutical microbiology. Chlorotetracycline (trade name: Aureomycin) was the first tetracycline discovered and remains a teaching example.

Given Data / Assumptions:

• We must identify the original industrial producer of chlorotetracycline.
• Options include several classic Streptomyces.

Concept / Approach:
Chlorotetracycline is produced by Streptomyces aureofaciens, historically associated with its golden pigmentation and the name “Aureomycin.” Other species listed are known for different products: S. rimosus (oxytetracycline), S. venezuelae (chloramphenicol), S. erythreus (erythromycin; now Saccharopolyspora erythraea).

Step-by-Step Solution:
Recall signature pairs: chlorotetracycline ↔ S. aureofaciens. Eliminate close but different tetracycline producers (S. rimosus → oxytetracycline). Eliminate producers of unrelated antibiotics. Choose S. aureofaciens.

Verification / Alternative check:
Historic discovery records and industrial strain catalogs consistently assign chlorotetracycline to S. aureofaciens.

Why Other Options Are Wrong:

• S. rimosus: oxytetracycline, not chlorotetracycline.
• S. venezuelae: chloramphenicol.
• S. erythreus: erythromycin (macrolide).

Common Pitfalls:
Confusing the tetracycline family variants and their distinct producers.

Final Answer:
Streptomyces aureofaciens