Streptomycin and actinomycin were discovered by

Options

A. Streptococcus
B. Staphylococcus
C. Lactobacillus
D. Saccharomyces

Answer

**Step-by-Step Solution:**

1. **Identify the Compounds**: The question asks about the discovery of two antibiotics: streptomycin and actinomycin.

2. **Research the Discovery of Streptomycin**:
- Streptomycin is an antibiotic that was discovered in 1943.
- It was isolated from the soil bacterium *Streptomyces griseus*.
- The key individuals involved in its discovery are biochemists Selman Waksman, Albert Schatz, and Elizabeth Bugie.

3. **Research the Discovery of Actinomycin**:
- Actinomycin was discovered earlier, in 1940.
- It was also isolated from a strain of *Streptomyces*, specifically *Streptomyces antibioticus*.
- The discovery of actinomycin is credited to Selman Waksman and his colleague Woodruff.

4. **Summarize the Findings**:
- Both streptomycin and actinomycin were discovered by researchers associated with the *Streptomyces* genus.
- The main contributors to the discovery of these antibiotics are Selman Waksman, Albert Schatz, Elizabeth Bugie, and Woodruff.

5. **Conclude the Answer**:
- Therefore, the correct answer to the question is that streptomycin and actinomycin were discovered by Selman Waksman and his colleagues.

**Final Answer**: Streptomycin and actinomycin were discovered by Selman Waksman, Albert Schatz, Elizabeth Bugie, and Woodruff, from the *Streptomyces* genus.

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