The ellagitaninn HeT inhibits the growth of microorganisms by interfering with the electron transport chain

GUSTAVO GABRIEL MARTOS

Congreso; XXXIV Jornadas Científicas de la Asociación de Biología de Tucumán; 2017

Previous reports showed that HeT affected the viability of several bacterial and fungal pathogens of plants and humans. However, little is known about the mechanism by which HeT exerts its antimicrobial activity. The objective of this work was to investigate how HeT exerts its antimicrobial effect. β-galactosidase unmasking experiments carried out with Enterococcus mundtii strain CRL35 (lacZ +) indicated that the action of HeT does not impair the integrity of the cell membrane. In addition, oxygen measurements showed that the application of HeT considerably decreased the oxygen consumption of Clavibacter michiganensis cultures. A similar effect was also observed in suspensions of cell membranes isolated from C. michiganensis. Furthermore, enzymatic assays performed on these membranes showed that HeT decreased NADH consumption and MTT reduction when the electron chain was blocked with KCN. These results suggest that HeT produces the interruption of the electron transport chain at the level of the dehydrogenase enzyme.