Antimicrobial activity of Adenanthera pavonina defensin APDEF1 against Saccharomyces cerevisiae

RIBEIRO SOARES, JULIA; REGENTE, M.; PINEDO, M. L.; DE LA CANAL, L.; GOMES, V.; CARVALHO, A.

Mar del Plata

Congreso; LI Congreso de la Sociedad Argentina de Investigación Bioquímica; 2015

Sociedad Argentina de Investigación Bioquímica

The aim of this work was to evaluate the antimicrobial activity of the plant defensin ApDef1 which was obtainedfrom Adenanthera pavonina seeds, against the yeast Saccharomyces cerevisiae. As methods, peptides were extractedfrom the seeds and submitted to ammonium sulfate fractionation, dialysed against distilled water and then submittedto chromatographic methods. A 7 kDa peptide was sequenced and tests were performed to evaluate its antimicrobialactivity by minimum inhibitory concentration (MIC) determination, membrane permeabilization and induction ofhydrogen peroxide capability. The primary structure of this peptide showed homology with plant defensins, whichwas named ApDef1. ApDef1 was able to inhibit the growth of S. cerevisiae, presenting MIC of 40 μg/mL andfungicide activity, it required a maximum of 18 h to cause the unfeasibility of cells and it was able to modify theyeast plasma membrane. The treatment with the 2.5 μg/mL of ApDef1 induced the production of hydrogen peroxideafter 18 h of assay. In conclusion, ApDef1 presents a strong antimicrobial activity against cells of yeast, killing themin 18 h. ApDef1 permeabilizes yeast membranes and causes increasing of hydrogen peroxide.