title: An insecticidal protein from Xenorhabdus ehlersii triggers prophenoloxidase activation and hemocyte decrease in Galleria mellonella.
abstract: The bacteria Xenorhabdus spp. are entomopathogenic symbionts that can produce several toxic proteins that interfere the immune system of insects. We purified an insecticidal protein from Xenorhabdus ehlersii, and designated it as XeGroEL with an estimated molecular mass of ~58 kDa. Galleria mellonella larva injected with XeGroEL presented prophenoloxidase activation and hemocyte decrease. XeGroEL can kill G. mellonella larva in 48 h with an LD(50) of 0.76 ± 0.08 μg/larva. Our results demonstrate that X. ehlersii possesses a toxic XeGroEL protein acting as a potential factor to activate proPO in host insect, which also provides a meaningful hypothesis to understand the interaction between nematode-symbiotic bacteria and host.
authors.affiliation: Key Laboratory of Integrated Pest Management in Crops, Ministry of Agriculture, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors.forename: Huaixing
authors.initials: H
authors.lastname: Shi
authors.forename: Hongmei
authors.initials: H
authors.lastname: Zeng
authors.forename: Xiufen
authors.initials: X
authors.lastname: Yang
authors.forename: Jing
authors.initials: J
authors.lastname: Zhao
authors.forename: Mingjia
authors.initials: M
authors.lastname: Chen
authors.forename: Dewen
authors.initials: D
authors.lastname: Qiu
mesh_terms: D000818:Animals; D004156:Catechol Oxidase / Q000378:metabolism*; D018834:Chaperonin 60 / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D015180:Electrophoresis, Gel, Two-Dimensional; D004792:Enzyme Precursors / Q000378:metabolism*; D006434:Hemocytes / Q000276:immunology*; D007306:Insecticides / Q000302:isolation & purification / Q000378:metabolism*; D007814:Larva / Q000276:immunology / Q000382:microbiology / Q000502:physiology; D007915:Lepidoptera / Q000276:immunology / Q000382:microbiology* / Q000502:physiology; D007928:Lethal Dose 50; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D008970:Molecular Weight; D017422:Sequence Analysis, DNA; D016019:Survival Analysis; D020593:Xenorhabdus / Q000737:chemistry / Q000472:pathogenicity*
chemical_list: D018834:Chaperonin 60; D004269:DNA, Bacterial; D004792:Enzyme Precursors; D007306:Insecticides; C038451:pro-phenoloxidase; D004156:Catechol Oxidase