title: Enhancing the utilization of host trehalose by fungal trehalase improves the virulence of fungal insecticide.
abstract: Entomopathogenic fungi proliferate in insect hemolymph by using host nutrients after penetrating the cuticle. To improve the virulence of the locust specific fungus, Metarhizium acridum, we genetically modified the fungus to overexpress ATM1, an endogenous hydrolase of trehalose, which is the main carbon source in insect hemolymph. Compared with the wild-type strain, Metarhizium acridum overexpressing ATM1 gene secreted more acid trehalase into locust hemolymph. The trehalose concentrations in locusts infected with the ATM1-overexpressing strain were 5.5 and 6.1 mmol/l, lower than that in locusts infected with the wild-type strain at 3 and 5 days post-inoculation, representing 44.5 and 60.7 % reduction, respectively. Correspondingly, overexpressing ATM1 accelerated the growth of Metarhizium acridum in host hemolymph, and the dose causing 50 % mortality (LD50) of the ATM1-overexpressing strain was reduced by 8.3-fold compared with the wild-type strain, suggesting that increasing the utilization of host nutrients by pathogens could be a promising way to improve the virulence of biopesticides based on parasites of pests.
authors.affiliation: Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing, 400045, People's Republic of China.|Chongqing Engineering Research Center for Fungal Insecticide, Chongqing University, Chongqing, 400045, People's Republic of China.|Key Laboratory of Gene Function and Regulation Technologies under Chongqing Municipal Education Commission, Chongqing University, Chongqing, 400045, People's Republic of China.
authors.forename: Guoxiong
authors.initials: G
authors.lastname: Peng
authors.affiliation: Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing, 400045, People's Republic of China.|Chongqing Engineering Research Center for Fungal Insecticide, Chongqing University, Chongqing, 400045, People's Republic of China.|Key Laboratory of Gene Function and Regulation Technologies under Chongqing Municipal Education Commission, Chongqing University, Chongqing, 400045, People's Republic of China.
authors.forename: Kai
authors.initials: K
authors.lastname: Jin
authors.affiliation: Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing, 400045, People's Republic of China.|Department of Cell Biology and Genetics, Fujian Medical University, Fuzhou, People's Republic of China.
authors.forename: Yingchun
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing, 400045, People's Republic of China. yuxianxia@cqu.edu.cn.|Chongqing Engineering Research Center for Fungal Insecticide, Chongqing University, Chongqing, 400045, People's Republic of China. yuxianxia@cqu.edu.cn.|Key Laboratory of Gene Function and Regulation Technologies under Chongqing Municipal Education Commission, Chongqing University, Chongqing, 400045, People's Republic of China. yuxianxia@cqu.edu.cn.
authors.forename: Yuxian
authors.initials: Y
authors.lastname: Xia
mesh_terms: D000818:Animals; D015870:Gene Expression; D006458:Hemolymph / Q000737:chemistry; D007313:Insecta / Q000382:microbiology* / Q000502:physiology*; D007928:Lethal Dose 50; D060847:Metabolic Engineering; D052981:Metarhizium / Q000201:enzymology* / Q000254:growth & development*; D016019:Survival Analysis; D014198:Trehalase / Q000235:genetics / Q000378:metabolism*; D014199:Trehalose / Q000378:metabolism*; D014774:Virulence
chemical_list: D014199:Trehalose; D014198:Trehalase
keywords: Acid trehalase; Growth; Metarhizium acridum; Nutrient usage; Virulence