PLASMID ADDICTION AS A NOVEL APPROACH FOR DEVELOPING A STABLE PLASMID VECTOR FOR XYLELLA FASTIDIOSA

• Author(s): Igo, Michele; Young, Glenn; Kirkpatrick, Bruce; Matsumoto, Ayumi;
• Abstract: The lack of genetic and molecular tools that can be used to study the biology of Xylella fastidiosa (Xf) has made it extremely difficult for researchers to use genetic methods to establish the importance of a particular gene in the development of Pierces disease (PD). During the period under review, we have focused on developing plasmid vectors that are stably maintained in Xf throughout the infection cycle. To increase the stability of autonomously replicating plasmid vectors, we have introduced two different types of stabilizing elements into plasmid vectors pXF004, pRL1342, and pBBR1MCS-5. These stabilizing elements include the plasmid addiction systems, hok/sok and parDE, and the active partitioning system, parA. We are currently examining how addition of these stability elements affects plasmid maintenance both in vitro and en planta. We have also developed two integration vectors, which will allow researchers to introduce genes into two different nonessential regions of the Xf chromosome. We are currently evaluating the properties of the insertion strains en planta to make sure that these strains still exhibit the normal PD infectious cycle and have begun to examine the usefulness of both of these vectors for complementation analysis in Xf.
• Publication Date: Nov 2006
• Journal: 2006 Pierce's Disease Research Symposium