Porphyromonas gingivalis tyrosine kinase is a fitness determinant in polymicrobial infections

Tn-Seq was used to identify P. gingivalis genes that confer fitness during cooperative growth with S. gordonii or F. nucleatum in a murine abscess model. After generating a saturating Porphyromonas gingivalis transposon library using Mariner-based transposon mutagenesis, this library was inoculated either alone (Pg) or in conjunction with Streptococuus gordonii (Sg) or with Fusobacterium nucleatum (Fn) subcutaneously into BALB/cJ mice. Bacteria recovered from developed abscesses were cultured in vitro for two passages and genomic DNA was isolated. Genomic DNA was also isolated from the P. gingivalis transposon library (Input) and was not used to infect mice and used as a control.