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bacterium. What once was a parasitic trick has now been
reengineered into a precision delivery tool for modern
biotechnology.

In the lab, researchers strip Agrobacterium of its tumor-
inducing genes and replace them with therapeutic
payloads—genes that code for biologic drugs like enzymes,
antibodies, or tolerizing peptides. This genetic cassette is
loaded into a plasmid—a circular strand of DNA—and
introduced into the bacterium. From there, the
Agrobacterium is used to “infect” plant tissue, often leaf
discs or cotyledons, in a controlled environment.

Once in contact with the plant cells, the bacterium activates
its natural gene transfer system, delivering the therapeutic
DNA into the plant’s genome. Depending on the
engineering strategy, this gene can be integrated in two
primary locations: the nuclear genome, which resides in
the plant’s central DNA repository, or the chloroplast
genome, the specialized genetic material within the
photosynthetic machinery of the cell.

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