- The Ti plasmid of Agrobacterium tumefaciens has been modified and used as a cloning vector. The Ti plasmid integrates a segment of its DNA, termed T-DNA, into the chromosomal DNA of its host plant cells.
- The T-DNA plasmid causes tumours. As gene transfer occurs without human effort, the bacterium is known as ‘natural genetic engineer’ of plants. Ti plasmids as vectors transfer foreign genes of interest into the target cells.