Exoproteinases of the type A in pathogenesis of insect bacterial diseases.
Immune inhibitors produced in infected larvae of Galleria mellonella by such entomopathogens as Pseudomonas aeruginosa, Serratia marcescens and Heterorhabditis bacteriophora effectively blocked in vitro bactericidal activity of insect haemolymph against Escherichia coli D31, both in Galleria mellonella and Pieris brassicae pupae previously vaccinated with Enterobacter cloacae. Even at a trace concentration, the extracellular proteinases, by proteolytic degradation, totally destroyed the activity of cecropin peptides from Galleria and cecropin-like and attacin-family proteins from Pieris, but no ability to destroy antibacterial activity was shown by extracts obtained from Galleria larvae killed by massive doses of bacterial saprophytes. It is suggested that by blocking antibacterial immune response of the host, the proteinases help the bacteria to multiply in the haemolymph, thus they could be considered an important factor in the pathogenesis of bacterial diseases of insects.
Andrejko
M
M
Department of Insect Pathology, Marie Curie-Skłodowska University, Lublin, Poland.
D000818:Animals; D000917:Antibody Formation / Q000276:immunology*; D001424:Bacterial Infections / Q000662:veterinary*; D005075:Biological Evolution; D010450:Endopeptidases / Q000378:metabolism*; D006458:Hemolymph / Q000276:immunology; D019476:Insect Proteins / Q000378:metabolism; D007915:Lepidoptera / Q000276:immunology* / Q000382:microbiology
D019476:Insect Proteins; D010450:Endopeptidases