title: Serine proteases activity is important for the interaction of nematophagous fungus Duddingtonia flagrans with infective larvae of trichostrongylides and free-living nematodes Panagrellus spp.
abstract: The nematode-trapping fungus Duddingtonia flagrans has been studied as a possible control method for gastrointestinal nematodes of livestock animals. These fungi capture and infect the nematode by cuticle penetration, immobilization, and digestion of the internal contents. It has been suggested that this sequence of events occurs by a combination of physical and enzymatical activities. The aim of this study was to investigate the participation of proteolytic enzymatic activity during the interaction of the nematophagous fungus D. flagrans with infective larvae of trichostrongylides and the free-living nematode Panagrellus spp. Protease inhibitors used interfered in the predatory activity of D. flagrans. However, only PMSF significantly reduced the mean number of Panagrellus spp. captured by D. flagrans in comparison with the control. The experiment with fluorogenic substrate showed that maximum urokinase activity during the interaction of the fungus with the infective larvae of trichostrongylides or Panagrellus spp. occurred within 7 or 1 h of incubation, respectively. The protease activity, especially of the serine class, may be important during the interaction between the fungus and nematodes.
authors.affiliation: Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, Avenida Alberto Lamego, 2000, Parque Califórnia, CEP 28013602, Campos dos Goytacazes, Rio de Janeiro, Brazil; Laboratório de Tecnologia em Bioquímica e Microscopia, Centro de Ciências Biológicas e da Saúde, Centro Universitário Estadual da Zona Oeste, Avenida Manuel Caldeira de Alvarenga, 1203, Campo Grande, Rio de Janeiro, RJ, CEP 23070-200, Brazil.
authors.forename: Daniela G
authors.initials: DG
authors.lastname: Cruz
authors.affiliation: Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, Avenida Alberto Lamego, 2000, Parque Califórnia, CEP 28013602, Campos dos Goytacazes, Rio de Janeiro, Brazil.
authors.forename: Luana M
authors.initials: LM
authors.lastname: Costa
authors.affiliation: Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, Avenida Alberto Lamego, 2000, Parque Califórnia, CEP 28013602, Campos dos Goytacazes, Rio de Janeiro, Brazil.
authors.forename: Letícia O
authors.initials: LO
authors.lastname: Rocha
authors.affiliation: Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, Avenida Alberto Lamego, 2000, Parque Califórnia, CEP 28013602, Campos dos Goytacazes, Rio de Janeiro, Brazil.
authors.forename: Claudio A
authors.initials: CA
authors.lastname: Retamal
authors.affiliation: Laboratório de Zootecnia e Nutrição Animal, Centro de Ciências e Tecnologias Agropecuárias, Universidade Estadual do Norte Fluminense, Avenida Alberto Lamego, 2000, Parque Califórnia, CEP 28013602, Campos dos Goytacazes, Rio de Janeiro, Brazil.
authors.forename: Ricardo A M
authors.initials: RA
authors.lastname: Vieira
authors.affiliation: Laboratório de Tecnologia em Bioquímica e Microscopia, Centro de Ciências Biológicas e da Saúde, Centro Universitário Estadual da Zona Oeste, Avenida Manuel Caldeira de Alvarenga, 1203, Campo Grande, Rio de Janeiro, RJ, CEP 23070-200, Brazil.
authors.forename: Sergio H
authors.initials: SH
authors.lastname: Seabra
authors.affiliation: Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Campus Reitor João David Ferreira Lima, s/n, Trindade, CEP 88040-900, Florianópolis, Santa Catarina, Brazil.
authors.forename: Carlos P
authors.initials: CP
authors.lastname: Silva
authors.affiliation: Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, Avenida Alberto Lamego, 2000, Parque Califórnia, CEP 28013602, Campos dos Goytacazes, Rio de Janeiro, Brazil.
authors.forename: Renato A
authors.initials: RA
authors.lastname: DaMatta
authors.affiliation: Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense, Avenida Alberto Lamego, 2000, Parque Califórnia, CEP 28013602, Campos dos Goytacazes, Rio de Janeiro, Brazil. Electronic address: cps@uenf.br.
authors.forename: Clóvis P
authors.initials: CP
authors.lastname: Santos
mesh_terms: D000818:Animals; D059586:Duddingtonia / Q000201:enzymology* / Q000254:growth & development*; D054884:Host-Pathogen Interactions; D007814:Larva / Q000382:microbiology; D017168:Rhabditida / Q000382:microbiology*; D057057:Serine Proteases / Q000378:metabolism*
chemical_list: D057057:Serine Proteases
keywords: Duddingtonia flagrans; Panagrellus spp.; Serine protease; Trichostrongylides and nematophagous fungi; Urokinase