Apoplastic polyamine oxidation plays different roles in local responses of tobacco to infection by the necrotrophic fungus Sclerotinia sclerotiorum and the biotrophic bacterium Pseudomonas viridiflava

MARINA M; MAIALE SJ; ROSSI FR; ROMERO FM; RIVAS EI; GARRIZ A; RUIZ OA; PIECKENSTAIN FL

Congreso; Reunión Annual de la Sociedad Brasilera de Bioquímica y Biología Molecular; 2009

Putrescine (Put), spermidine (Spd) and spermine (Spm), known as polyamines (PAs), are essential for growth and development of all living organisms. Plants synthesize Put from arginine or ornithine, by two alternative pathways involving arginine decarboxylase (ADC) and ornithine decarboxylase (ODC), respectively. In all organisms, Spd is synthesized from Put and Spm from Spd by the addition of an aminopropyl group. The enzymes involved are spermidine synthase (Spd Syn) and spermine synthase (Spm Syn), respectively and adenosyl- methionine decarboxylase (AdoMetDc). On the other hand, polyamines can be deaminated by amine oxidases. Diamine oxidases (DAOs) mainly deaminate Put, and polyamine oxidases (PAOs) mainly act on Spd and Spm. There is a growing interest on the role of plant polyamines during the interaction with microorganisms, although polyamine functions during the interaction with bacterial and fungal pathogens is far from being clear.