title: Boophilus microplus infection by Beauveria amorpha and Beauveria bassiana: SEM analysis and regulation of subtilisin-like proteases and chitinases.
abstract: Beauveria bassiana is a well-known broad-range arthropod pathogen which has been used in biological control of several pest insects and ticks such as Boophilus microplus. Beauveria amorpha has both endophytic and entomopathogenic characteristics, but its capacity for biological control has still not been studied. During the processes of host infection, B. bassiana and B. amorpha produce several hydrolytic extracellular enzymes, including proteases and chitinases, which probably degrade the host cuticle and are suggested to be pathogenicity determinants. To access the role of these enzymes during infection in the tick B. microplus, we analyzed their secretion during fungus growth in single and combined carbon sources, compared to complex substrates such as chitin and B. microplus cuticle. Chitin and tick cuticle-induced chitinase in both fungus and protease was induced only by tick cuticle. SEM analysis of B. amorpha and B. bassiana infecting B. microplus showed apressorium formation during penetration on cattle tick cuticle.
authors.affiliation: Instituto de Biotecnologia, Universidade de Caxias do Sul, Caxias do Sul, RS, Brazil.
authors.forename: Roberta Alvares
authors.initials: RA
authors.lastname: Campos
authors.forename: Walquíria
authors.initials: W
authors.lastname: Arruda
authors.forename: Juliano Tomazzoni
authors.initials: JT
authors.lastname: Boldo
authors.forename: Márcia Vanusa
authors.initials: MV
authors.lastname: da Silva
authors.forename: Neiva Monteiro
authors.initials: NM
authors.lastname: de Barros
authors.forename: João Lúcio
authors.initials: JL
authors.lastname: de Azevedo
authors.forename: Augusto
authors.initials: A
authors.lastname: Schrank
authors.forename: Marilene Henning
authors.initials: MH
authors.lastname: Vainstein
mesh_terms: D000818:Animals; D001203:Ascomycota / Q000201:enzymology* / Q000302:isolation & purification / Q000648:ultrastructure; D002686:Chitin / Q000378:metabolism; D002688:Chitinases / Q000378:metabolism*; D010447:Peptide Hydrolases / Q000378:metabolism*; D010571:Pest Control; D013987:Ticks / Q000382:microbiology* / Q000648:ultrastructure
chemical_list: D002686:Chitin; D002688:Chitinases; D010447:Peptide Hydrolases