What is true iv.r.t. the characteristics of the organism Agrobacterium tumefaciens involved in genetic engineer- ing processes?

Options

A. Gram negative organism
B. The plasmid is known as Ti Plasmid (Tumour inducing)
C. Causes crown gall disease in several dicot plants
D. All of these

Answer

### Step-by-Step Solution:

1. **Identify the Organism**: The organism in question is Agrobacterium tumefaciens, which is a bacterium commonly used in genetic engineering.

2. **Understand its Characteristics**: Agrobacterium tumefaciens is known for its role in causing crown gall disease in dicot plants. This disease is characterized by the formation of tumors.

3. **Plasmid Involvement**: The bacterium contains a tumor-inducing plasmid known as the T-DNA (Transfer DNA). This T-DNA is responsible for transferring genes from the bacterium into the host plant, leading to tumor formation.

4. **Pathogenic Nature**: Agrobacterium tumefaciens is classified as a gram-negative bacterium, which is significant for its identification and understanding of its pathogenicity.

5. **Genetic Engineering Applications**: In genetic engineering, the T-DNA can be modified. The genes responsible for tumor formation can be removed, and the plasmid can be repurposed as a cloning vector. This modified plasmid can then be used to introduce desired genes into the plant without causing disease.

6. **Conclusion**: The true statements regarding Agrobacterium tumefaciens include:
- It is a gram-negative bacterium.
- It possesses a T-DNA plasmid.
- It causes crown gall disease in dicot plants.
- All of the above statements are correct.

### Final Answer:
All of the statements regarding Agrobacterium tumefaciens are true.

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