Ellagitannin HeT obtained from strawberry leaves is oxidized by bacterial membranes and inhibits the respiratory chain

MAMANI, ALICIA; KATZ, NÉSTOR E.; MARTOS, GUSTAVO G.; ABATE, PEDRO O.; MARTOS, GUSTAVO G.; DÍAZ RICCI, JUAN C.; ABATE, PEDRO O.; DÍAZ RICCI, JUAN C.; FILIPPONE, MARÍA P.; CASTAGNARO, ATILIO P.; FILIPPONE, MARÍA P.; CASTAGNARO, ATILIO P.; MAMANI, ALICIA; KATZ, NÉSTOR E.

FEBS Open Bio

Wiley

Año: 2017 p. 211 - 218

2211-5463

Plant secondary metabolism produces a variety of tannins that have a widerange of biological activities, including activation of plant defenses andantimicrobial, anti-inflammatory and antitumoral effects. The ellagitanninHeT (1-O-galloyl-2,3;4,6-bis-hexahydroxydiphenoyl-b-D-glucopyranose) fromstrawberry leaves elicits a strong plant defense response, and exhibits antimicrobial activity associated to the inhibition of the oxygen consumption, but its mechanism of action is unknown. In this paper we investigate the influence of HeT on bacterial cell membrane integrity and its effect on respiration.A b-galactosidase unmasking experiment showed that HeT does notdisrupt membrane integrity. Raman spectroscopy analysis revealed that HeTstrongly interacts with the cell membrane. Spectrochemical analysis indicatedthat HeT is oxidized in contact with bacterial cell membranes, and functionalstudies showed that HeT inhibits oxygen consumption, NADH andMTT reduction. These results provide evidence that HeT inhibits therespiratory chain.