pIGWZ12 – a cryptic plasmid with a modular structure

Publication date: Available online 15 April 2015 Source:Plasmid Author(s): Piotr Zaleski , Paweł Wawrzyniak , Agnieszka Sobolewska , Natalia Łukasiewicz , Piotr Baran , Katarzyna Romańczuk , Katarzyna Daniszewska , Piotr Kierył , Grażyna Płucienniczak , Andrzej Płucienniczak We studied the detailed structure of the cryptic plasmid pIGWZ12, which was isolated from an Escherichia coli strain. pIGWZ12 is composed of two structural modules of distinct evolutionary origin. The REP module, which contains all the features necessary for replication and stable maintenance in the bacterial cell, was assigned by genotyping to the IncF family. The MOB module, which is responsible for plasmid mobilization, shows significant homology to MOBQ modules from broad-host-range plasmids belonging to the RSF1010/R1162 family. We showed that iterons located in the origin of replication are the target for specific binding by the replication initiator protein RepApIGWZ12. Furthermore, we proved that the promoter for the repA gene overlaps with the iterons, and that the latter are the sole determinant of incompatibility. We performed a mutagenesis analysis of the MOBpIGWZ12 module and characterized the roles played by all identified genes (mobA and mobC), as well as the role played by oriT in mobilization. Finally, we showed that it was possible to remove the MOB module from pIGWZ12 without any loss in plasmid replication and stability. Furthermore, the MOBpIGWZ12 module was fully...
Source: Plasmid - Category: Biotechnology Source Type: research