Mally, Manuela Cornelis, Guy R. <jats:title>ABSTRACT</jats:title> <jats:p> <jats:italic>Capnocytophaga canimorsus</jats:italic>, a commensal bacterium from canine oral flora, has been isolated throughout the world from severe human infections caused by dog bites. Due to the low level of evolutionary relationship to <jats:italic>Proteobacteria</jats:italic>, genetic methods suitable for the genus <jats:italic>Capnocytophaga</jats:italic> needed to be established. Here, we show that Tn<jats:italic>4351</jats:italic>, derived from <jats:italic>Bacteroides fragilis</jats:italic>, could be introduced by conjugation into <jats:italic>C. canimorsus</jats:italic> and conferred resistance to erythromycin. By mapping and sequencing a naturally occurring plasmid isolated from a clinical isolate of <jats:italic>C. canimorsus</jats:italic>, we identified a <jats:italic>repA</jats:italic> gene that allowed us to construct <jats:italic>Escherichia coli-Capnocytophaga</jats:italic> shuttle vectors. Most commonly used antibiotic markers were not functional in <jats:italic>C. canimorsus</jats:italic>, but cefoxitin (<jats:italic>cfxA</jats:italic>), tetracycline (<jats:italic>tetQ</jats:italic>), and erythromycin (<jats:italic>ermF</jats:italic>) resistances could be used as markers for plasmid maintenance in <jats:italic>C. canimorsus</jats:italic> and even in some other <jats:italic>Capnocytophaga</jats:italic> spp. Shuttle vectors were introduced into <jats:italic>C. canimorsus</jats:italic> either by conjugation using the origin of transfer (<jats:italic>oriT</jats:italic>) of RP4 or by electrotransformation. Taking advantage of the promoter of <jats:italic>ermF</jats:italic>, an expression vector was constructed. Finally, a method that allows site-directed mutagenesis is described. All these genetic tools pave the way, not only for molecular studies of the pathogenesis of <jats:italic>C. canimorsus</jats:italic>, but also for studies of other oral <jats:italic>Capnocytophaga</jats:italic> species.</jats:p> application/pdf https://sonar.ch/global/documents/133760 eng info:eu-repo/semantics/altIdentifier/doi/10.1128/aem.01218-08 info:eu-repo/semantics/altIdentifier/issn/0099-2240 info:eu-repo/semantics/openAccess Applied and Environmental Microbiology. - American Society for Microbiology. - 2008, vol. 74, no. 20, p. 6369-6377 Biotechnology Food Science Ecology Applied Microbiology and Biotechnology Genetic Tools for Studying Capnocytophaga canimorsus http://purl.org/coar/resource_type/c_6501