XXXV Reunião Anual da SBBqResumoID:8885


Partial purification of a spore surface lipase from the entomopathogenic and acaricide fungus Metarhizium anisopliae
Silva, W.O.B.; Berger, M.; Santi, L.; Pinto, A.F.M.; Guimarães, J.A.; Schrank, A.; Vainstein, M.H.

Centro de Biotecnologia – UFRGS

The entomopathogenic fungus Metarhizium anisopliae (Metsch.) Sorokin is a well-characterized, broad host-range arthropod pathogen employed in biological control of agricultural pests. Entomopathogenic fungi actively invade their hosts through the cuticle by mechanical pressure, via apressorium formation, and enzymatic degradation by synergistic action of hydrolases, as chitinases and proteases. The present work describes the purification and characterization of a spore surface lipase from M. anisopliae. Spores from M. anisopliae produced in rice as substrate were immersed and strongly shacked in Tris-HCl buffer 50mM pH 8.0 containing 0.25% Triton X-100 for 5 min. The resulting supernatant was filtrated and applied on a DEAE-Sepharose column. Elution of proteins was done with a NaCl linear gradient (0-1.0 M). The fractions with lipolytic activity were applied on a gel filtration column Superose 12, followed by another step on a Mono-Q column and as the last purification step a Superose 12 was used. For all purification steps, the same buffer as for extraction of spore surface proteins was used. All chromatographic steps were done in FPLC purification system. The fractions from each purification step were analyzed by zymmograms and activity assays using pNP-Palmitate as substrate. The last step of purification showed only one fraction with lipolytic activity containing just two protein bands visualized in a SDS-PAGE electrophoresis. The next stages of this work will be the conclusion of the purification and characterization of the spore surface lipase from M. anisopliae and the elucidation of its function.

 Supported by CAPES, CNPq e FAPERGS.