CHARACTERIZATION OF ACID PEPTIDASES SECRETED BY PLANT-PATHOGENIC FUNGUS Botrytis cinerea

MARÍA VICTORIA REVUELTA; NICOLÁS ARANCIAGA; JUAN PABLO CÓRDOBA; LARA NEGRIN; FACUNDO ORTS; REBECA PÉREZ; ANABELA POULSEN-HORNUM; LARA SÁNCHEZ-RIZZA; ERIKA SCHOENFELD; SOLEDAD ISLAS; ROCÍO LARRECHE; ENRIQUE PODAZA; JJ ESPINO; ANA MARÍA LAXALT; ARJEN TEN HAVE

Puerto Madryn, Provincia de Chubut

Congreso; XLVI Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2010

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB)

Botrytis cinerea causes gray mold, a devastating disease of various plants of economic interest. This necrotroph grows at moderate temperatures but also as low as 4°C at which crops are stored. Infection with B. cinerea depends on cell wall degrading enzymes such as endopolygalacturonases (ten Have et al., 1998). Cell walls also contain protein, hence peptidases might also contribute to virulence. B. cinerea secretes aspartic peptidases (APs, Espino et al., 2010; ten Have et al., 2004) which act at low pH values, in correspondence with the low pH reported during B. cinerea infection (van Kan, 2006). Espino also reported a secreted glutamic peptidase (GP) and six secreted sedolisins. It is not known how these enzymes contribute to the secreted peptidase activity. We used a BcAP8 knock-out mutant, which shows 80% reduction in secreted peptidase activity to study the spectrum of other peptidase activities. We detected an inducible GP activity and data suggest the presence of a sedolisin activity. In planta analysis showed mostly AP activity and finally we show AP activity at low temperatures.