A WHEAT GERMIN-LIKE PROTEIN THAT INHIBITS TRYPSIN AFFECTS THE NORMAL GROWTH OF FUNGUS AND BACTERIA

MARCHETTI, M.F.; MANSILLA, A.Y.; CONDE, R.D.; MENDIETA, J.R.

Mar del Plata

Congreso; VIII Congreso de Microbiologia General; 2012

Sociedad Argentina de Microbiologia General

The serine-type proteolytic activity of the intercellular fluid of wheat leaf is controlled by a germin-like protein that inhibits trypsin named GLPI. Its capacity to inhibit serine proteasesis the first described within both germins and germin-like proteins. Subsequently, in wheat plants whose seeds were inoculated with the biocontroller fungus Trichoderma spp, we found thatGLPI takes part in the control of the disease caused by the fungus Septoria tritici. Also, GLPI has at least two more activities linked to responses to different types of stress:pyrophosphatase/phosphodiesterase and superoxide dismutase. Indeed, it has been described that, besides controlling proteolysis and serving as storage proteins in seeds, protease inhibitorsmay take part in defense responses against phytopathogenic microorganisms. Therefore, the objective of this work was to test the antimicrobial activity of GLPI against the plant pathogensFusarium solani, Phytophthora infestans and Pseudomona syringae. The obtained data suggest that GLPI exerts its microbicide ability by interacting with plasma membrane. Then, stressing itsrole in plant resistance against pathogen attack, this study show that GLPI has an associated antimicrobial activity.