title: The acid trehalase, ATM1, contributes to the in vivo growth and virulence of the entomopathogenic fungus, Metarhizium acridum.
abstract: For pathogens, the ability to acquire available nutrients in a host is a key to their survival and replication. Entomopathogenic fungi of the genus Metarhizium secrete trehalase, which enables them to use trehalose, the predominant sugar in insects. Here, the roles of the acid trehalase gene (ATM1) in the in vivo growth and virulence of Metarhizium acridum were investigated. Phenotypic analysis showed that disruption of ATM1 severely reduced fungal growth on exogenous trehalose as the sole carbon source. Bioassays showed that ATM1 disruption impaired the virulence of M. acridum against the host insect Locusta migratoria. The ATM1-disruption strain (ΔATM1) grown more slowly than the wild-type strain (WT) and complemented transformant (CP) in locust blood, which was consistent with the activity of acid trehalase in the hemolymph of infected locusts. Correspondingly, the trehalose concentration in locusts infected by ΔATM1 was significantly higher than in those infected by WT or CP. Thus, ATM1 disruption led to a significant reduction in virulence by adversely affecting the fungal growth in insect hemolymph, which resulted from the inability of the mutant strain to use trehalose.
authors: Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing 400045, PR China; Chongqing Engineering Research Center for Fungal Insecticide, Chongqing 400045, PR China; Key Laboratory of Gene Function and Regulation Technologies under Chongqing Municipal Education Commission, Chongqing 400045, PR China.
authors: Kai
authors: K
authors: Jin
authors: Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing 400045, PR China; Chongqing Engineering Research Center for Fungal Insecticide, Chongqing 400045, PR China; Key Laboratory of Gene Function and Regulation Technologies under Chongqing Municipal Education Commission, Chongqing 400045, PR China.
authors: Guoxiong
authors: G
authors: Peng
authors: Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing 400045, PR China.
authors: Yingchun
authors: Y
authors: Liu
authors: Genetic Engineering Research Center, School of Life Sciences, Chongqing University, Chongqing 400045, PR China; Chongqing Engineering Research Center for Fungal Insecticide, Chongqing 400045, PR China; Key Laboratory of Gene Function and Regulation Technologies under Chongqing Municipal Education Commission, Chongqing 400045, PR China. Electronic address: yuxianxia@cqu.edu.cn.
authors: Yuxian
authors: Y
authors: Xia
mesh_terms: D000818:Animals; D048188:Locusta migratoria / Q000382:microbiology; D052981:Metarhizium / Q000254:growth & development / Q000378:metabolism* / Q000472:pathogenicity; D014198:Trehalase / Q000235:genetics / Q000378:metabolism*; D014199:Trehalose / Q000378:metabolism
chemical_list: D014199:Trehalose; D014198:Trehalase
keywords: Acid trehalase; Growth; Metarhizium acridum; Nutrient usage; Virulence