Antimicrobial activity of a Kazal-type inhibitor from Toxoplasma gondii against plant pathogens

SANCHEZ, EDWIN F; CORIGLIANO, MARIANA G; PARIANI, SEBASTIÁN A; ROMERO, MATÍAS F; PIECKENSTAIN, FERNANDO L; CLEMENTE, MARINA

Mar del Plata

Congreso; 51 Annual Meeting. Argentine Society for Biochemistry and Molecular Biology Research; 2015

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

Plants are susceptible to be infected by severalpathogens that secrete proteinases. A serine proteinase inhibitor of Toxoplasma gondii (TgPI) has shown to bea potent trypsin, chymotrypsin and elastase inhibitor. Since serine inhibitorshave been established as an effective protective system for plants, we proposeto evaluate the antimicrobial activity of the recombinant TgPI (rTgPI) againstplant pathogens with the object to use this inhibitor as a novel strategy forimproving plant pathogen resistance. Previously, we showed that rTgPI hasbacteriostatic effect on Pseudomonas growth. Following with the characterization of the inhibitory properties ofrTgPI, the germination of Botrytiscinerea conidia in culture medium supplemented with rTgPI was analyzed. Germinationrates of B. cinerea conidia in themedium containing rTgPI were significantly lower than control. To investigate whetherrTgPI is able to inhibit the infection inplanta, A. thaliana wereco-inoculated with B. cinerea or P. siryngae and rTgPI. After B. cinerea infection, necrotic area was measured.Leaves co-inoculated showed a reduction of 70-80% of necrotic area respect tothe controls. Similarly, bacterial counts were significantly reduced in leavesco-inoculated with P. siryngae andrTgPI respect to the controls. In conclusion, rTgPI would be able to inhibitthe infectivity capacity of these plant pathogens.