Bacterial partitioning proteins affect the subcellular location of broad-host-range plasmid RK2.
It has been demonstrated that plasmids are not randomly distributed but are located symmetrically in mid-cell, or (1/4), (3/4) positions in bacterial cells. In this work we compared the localization of broad-host-range plasmid RK2 mini-replicons, which lack an active partitioning system, in Escherichia coli and Pseudomonas putida cells. In E. coli the location of the plasmid mini-replicon cluster was at the cell poles. In contrast, in Pseudomonas cells, as a result of the interaction of chromosomally encoded ParB protein with RK2 centromere-like sequences, these mini-derivatives were localized in the proximity of mid-cell, or (1/4), (3/4) positions. The expression of the Pseudomonas parAB genes in E. coli resulted in a positional change in the RK2 mini-derivative to the mid-cell or (1/4), (3/4) positions. Moreover, in a P. putida parAB mutant, both RK2 mini-derivatives and the entire RK2 plasmid exhibited disturbances of subcellular localization. These observations raise the possibility that in certain bacteria chromosomally encoded partitioning machinery could affect subcellular plasmid positioning.
Kolatka
Katarzyna
K
Department of Molecular and Cellular Biology, Intercollegiate Faculty of Biotechnology, University of Gdansk, Kladki 24, 80-822 Gdansk, Poland.
Witosinska
Monika
M
Department of Molecular and Cellular Biology, Intercollegiate Faculty of Biotechnology, University of Gdansk, Kladki 24, 80-822 Gdansk, Poland.
Pierechod
Marcin
M
Department of Molecular and Cellular Biology, Intercollegiate Faculty of Biotechnology, University of Gdansk, Kladki 24, 80-822 Gdansk, Poland.
Konieczny
Igor
I
Department of Molecular and Cellular Biology, Intercollegiate Faculty of Biotechnology, University of Gdansk, Kladki 24, 80-822 Gdansk, Poland.