The natural transformation of the soil bacteria Pseudomonas stutzeri and Acinetobacter sp. by transgenic plant DNA strictly depends on homologous sequences in the recipient cells

Abstract

The nptII + gene present in the genome of transgenic potato plants transforms naturally competent cells of the soil bacteria Pseudomonas stutzeri and Acinetobacter BD413 (both harboring a plasmid with an nptII gene containing a small deletion) with the same high efficiency as nptII + genes on plasmid DNA (3×10 −5–1×10 −4 transformants per nptII +) despite the presence of a more than 10 6-fold excess of plant DNA. However, in the absence of homologous sequences in the recipient cells the transformation by nptII + dropped by at least about 10 8-fold in P. stutzeri and 10 9-fold in Acinetobacter resulting in the latter strain in ≤1×10 −13 transformants per nptII +. This indicated a very low probability of non-homologous DNA fragments to be integrated by illegitimate recombination events during transformation.