Figure 2.

Type II secretion and CpaA are similarly required for full virulence in the G. mellonella infection model. G. mellonella larvae were injected with 10 μl of either M2, ΔgspD, ΔcpaA, or the complemented strains at an inoculum of ∼1 × 10⁷. Infected larvae were incubated at 37 °C and monitored for viability over time. Viability was determined by melanin accumulation and mobility. Larvae infected with ΔgspD or ΔcpaA had ∼50% survival at 24 h. 25% of the larvae infected with M2 survived after 24 h. Larvae infected with the ΔgspD or ΔcpaA complemented strains had 17% survival at 24 h post-infection. The difference in percent survival of larvae infected with ΔgspD or ΔcpaA relative to the wild-type or complemented strains is statistically significant (Mantel Cox p = 0.0447).