Survival of G. mellonella following infection with 106 cfu per larva of Y. pseudotuberculosis wild type IP32953 and defined mutants. Wild type (IPWT) was compared to insertional mutants of ifp (IPΔIFP) and inv (IPΔINV), an ifp and inv double mutant (IPΔIFPΔINV) and an ifp mutant with complemented ifp (IPΔIFPpIFP). Phosphate buffered saline (PBS) injection and uninfected (UI) Galleria were utilised as controls. Assays were performed on at least three independent occasions, each with 10 larvae per strain. Statistical analysis by non-parametric t-test with statistically significant results marked with * (p =< 0.05).