First artificial recombinant DNA molecule was created by:

Options

A. linking of gene encoding antibiotic resistance with a native plasmid of Salmonella typhimuriumn
B. linking of gene encoding fertility factor with a na- tive plasmid o E. coli
C. linking of gene encoding .-galactosidase with a native plasmid of Agrobacterium tumefac iens
D. linking of gene encoding lactase with a native plas-mid off. coli

Answer

**Step-by-Step Solution:**

1. **Understanding Recombinant DNA**: The first step is to understand what recombinant DNA is. Recombinant DNA is formed by combining DNA from two different sources.

2. **Identifying the First Artificial Recombinant DNA**: The question asks about the first artificial recombinant DNA molecule. This was created by linking a gene that encodes antibiotic resistance with a plasmid.

3. **Recognizing the Key Scientists**: The scientists credited with creating the first recombinant DNA are Stanley Cohen and Herbert Boyer. They achieved this in 1972.

4. **The Process**: The process involved isolating a gene that confers antibiotic resistance and linking it to a native plasmid from the bacterium Salmonella typhimurium. This was done using restriction enzymes to cut the DNA at specific sites.

5. **Analyzing the Options**: The options provided include various combinations of genes and plasmids. The correct option is the one that mentions the gene encoding antibiotic resistance linked with the native plasmid of Salmonella typhimurium.

6. **Conclusion**: Therefore, the first artificial recombinant DNA molecule was created by linking the gene encoding antibiotic resistance with a native plasmid of Salmonella typhimurium.

**Final Answer**: The first artificial recombinant DNA molecule was created by linking the gene encoding antibiotic resistance with a native plasmid of Salmonella typhimurium.

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