Targeted gene disruption in Francisella tularensis by group II introns.

Methods

South Texas Center for Emerging Infectious Diseases and Department of Biology, University of Texas San Antonio, San Antonio, TX 78249, USA.

Published: November 2009

Francisella tularensis is a highly infectious Gram-negative bacterium that is the causative agent of tularemia. Very little is known about the molecular mechanisms responsible for F. tularensis virulence, in part due to the paucity of genetic tools available for the study of F. tularensis. We have developed a gene knockout system for F. tularensis that utilizes retargeted mobile group II introns, or "targetrons". These targetrons disrupt both single and duplicated target genes at high efficiency in three different F. tularensis subspecies. Here we describe in detail the targetron-based method for insertional mutagenesis of F. tularensis genes, which should facilitate a better understanding of F. tularensis pathogenesis. Group II introns can be adapted to inactivate genes in bacteria for which few genetic tools exist, thus providing a powerful tool to study the genetic basis of bacterial pathogenesis.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2801413PMC
http://dx.doi.org/10.1016/j.ymeth.2009.04.011DOI Listing

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