Diversity of pJP4-transconjugants from activated sludge

摘要

To extend the knowledge about the possible host range of IncP1-β plasmids in the environment, an agar surface mating was carried out with a donor strain carrying the 2,4-D degradative plasmid pJP4 and an undefined recipient community derived from activated sludge. Culturable transconjugants were isolated from this conjugation experiment, and a subset of isolates was identified by partial sequencing of their 16S rRNA genes. All were members of the proteobacteria, particularly of Rhizobiaceae, Comamonadaceae, and the γβ-branch of proteobacteria. The isolates were screened for their ability to grow on 2,4-D as the sole source of carbon and energy, but only members of the genera Pseudomonas and Delftia were able to grow under these conditions.