The prokaryote that is credited with construction of the first recombinant DNA by linking an antibiotic resistance gene with its native plasmid is

Options

A. Escherichia coli
B. Pneumococcus pneumonia
C. Salmonella typhimurium
D. Agrobacterium tumefactions

Answer

To solve the question regarding the prokaryote credited with the construction of the first recombinant DNA by linking an antibiotic resistance gene with its native plasmid, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Recombinant DNA**:
- Recombinant DNA technology involves combining DNA from different sources. In this case, it involves linking an antibiotic resistance gene with a plasmid.

2. **Identifying the Prokaryote**:
- The question lists several prokaryotes: E. coli, Pneumococcus pneumoniae, Salmonella typhimurium, Agrobacterium tumefaciens.
- We need to identify which of these was involved in the first construction of recombinant DNA.

3. **Historical Context**:
- The first successful construction of recombinant DNA was achieved by scientists Stanley Cohen and Herbert Boyer in 1972.
- They used a plasmid from a specific bacterium to create recombinant DNA.

4. **Linking the Antibiotic Resistance Gene**:
- The antibiotic resistance gene was linked to a native plasmid. The native plasmid used in this experiment was derived from Salmonella typhimurium.

5. **Conclusion**:
- Therefore, the prokaryote credited with the construction of the first recombinant DNA by linking an antibiotic resistance gene with its native plasmid is **Salmonella typhimurium**.

### Answer:
The prokaryote credited with the construction of the first recombinant DNA is **Salmonella typhimurium**.

---