Effects of insecticidal proteins of Enterobacter cloacae NK on cellular immunity of Galleria mellonella larvae

produces insecticidal proteins capable of causing toxicity in pests, but the insecticidal mechanisms of these proteins for insect control remain unclear. To elucidate the mechanisms, the purified insecticidal protein from NK was administered to larvae either by intraperitoneal injection or by feeding. The number of hemocytes, apoptosis in immune cells, and polyphenol oxidase (PO) activity of larvae were detected by hemocytometer, Annexin V-FITC/PI, and UV-vis spectrophotometer, respectively. With the extension of the invasion time of NK insecticidal protein, the number of hemocytes in larvae decreased significantly (