The construction of the first recombinant DNA was done by using the native plasmid of

Options

A. E.coli
B. Salmonella typhimurium
C. B.thuringiensis
D. Yeast

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks about the native plasmid used in the construction of the first recombinant DNA.

2. **Identifying the Options**: The options provided are:
- E. coli
- Salmonella typhimurium
- Bacillus thuringiensis
- Yeast

3. **Background Knowledge**: The first recombinant DNA was constructed using a plasmid that had the ability to confer antibiotic resistance. This was a crucial aspect of the experiment.

4. **Analyzing Each Option**:
- **E. coli**: While E. coli is widely used in recombinant DNA technology, it was not the source of the plasmid for the first recombinant DNA.
- **Salmonella typhimurium**: This organism has a plasmid that contains genes for antibiotic resistance, making it a strong candidate for the construction of the first recombinant DNA.
- **Bacillus thuringiensis**: This bacterium is known for its insecticidal properties but is not associated with the first recombinant DNA.
- **Yeast**: While yeast can be used in genetic engineering, it was not the source of the first recombinant DNA.

5. **Conclusion**: Based on the analysis, the correct answer is **Salmonella typhimurium**. This organism's plasmid was used to create the first recombinant DNA, which included a gene for antibiotic resistance.

**Final Answer**: Salmonella typhimurium

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