Transfer of plastid DNA from tobacco to the soil bacterium Acinetobacter sp. by natural transformation.

Acquisition of new genetic information by horizontal gene transfer is a major mechanism of genetic adaptation and evolution in prokaryotes. Naturally transformable cells of Acinetobacter sp. were exposed to plant DNA from leaf and root tissue of transplastomic tobacco. With the aadA gene (resistance against spectinomycin and streptomycin) as anchor sequence, the transfer of segments of the tobacco plastid DNA to Acinetobacter by homology-facilitated illegitimate recombination occurred at a frequency of 1.2 x 10(-7) per cell, which was about 0.1% of the frequency of fully homologous transfers. Without anchor sequence, transfer was not detected (