Metarhizium anisopliae lipolytic activity plays a pivotal role in Rhipicephalus (Boophilus) microplus infection.
Lipases secreted by Metarhizium anisopliae, an important biological control agent, could potentially be involved in the host infection process. Here, we present the activity profile during the host infection process and the effect of lipase activity inhibitor ebelactone B on infection. The previous treatment of spores with lipase activity inhibitor, ebelactone B, completely inhibited lipolytic activity and prevented the infection of the Rhipicephalus (Boophilus) microplus host. The results herein presented prove, for the first time, the importance of lipase activity in M. anisopliae host infection process. The filamentous fungus Metarhizium anisopliae is one of the most important and studied biological agents for the control of several arthropod pests, including the cattle tick Rhipicephalus (Boophilus) microplus. Lipases secreted by M. anisopliae could potentially be involved in the host infection process. This work presents the activity profile during the host infection process and the effect of lipase activity inhibitor ebelactone B on infection. During the course of tick exposure to spores (6-120 h) lipase activity increased from 0.03 ± 0.00 U to 0.312 ± 0.068 U using rho NP palmitate as substrate. In zymograms, bands of lipase activity were detected in ticks treated with spores without inhibitor. The previous treatment of spores with lipase activity inhibitor, ebelactone B, completely inhibited lipolytic activity, at all times specified, and prevented the infection of the R. microplus host. Spores treated with the inhibitor did not germinate on the tick, although this effect was not observed in the culture medium. The results herein presented prove, for the first time, the importance of lipase activity in M. anisopliae host infection process.
Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, P.O. Box 15005, 91501-070 Porto Alegre, RS, Brazil. walterbeys@cbiot.ufrgs.br
Walter O
WO
Beys da Silva
Lucélia
L
Santi
Augusto
A
Schrank
Marilene H
MH
Vainstein
D000818:Animals; D054884:Host-Pathogen Interactions; D008049:Lipase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D052981:Metarhizium / Q000201:enzymology* / Q000502:physiology*; D008855:Microscopy, Electron, Scanning; D010572:Pest Control, Biological; D048494:Rhipicephalus / Q000382:microbiology* / Q000648:ultrastructure; D013172:Spores, Fungal / Q000201:enzymology / Q000502:physiology
D008049:Lipase