Figure 6. Metamorphosis of G. mellonella larvae following infection with pathogenic and non-pathogenic L. monocytogenes. Injection of pathogenic EGD-e or non-pathogenic heat killed (HK) EGD-e into last-instar larvae induced opposing developmental effects. Injection with HK EGD-e induced the precocious formation of pupae whereas infection with live wild type pathogenic EGD-e caused a significant delay in comparison to control larvae treated with 0.9% NaCl. The larvae were incubated at 37 °C and reared on an artificial diet. Results represent mean values of at least three independent measurements ± standard deviations from at least 20 larvae per treatment (***P < 0.0005; ns, not significant).