Oligosaccharide recognition signals and defence reactions in marine plant-microbe interactions

Recent findings on the involvement of oligosaccharide signals in pathogen r ecognition and defence reactions in marine algae shine a new light on the e cology of their interactions with associated microorganisms. Since the mari ne environment encompasses lineages that have diverged a long time ago from the terrestrial phyla, these results suggest that cell-cell recognition pa thways typical of terrestrial plants appeared very early in the evolution o f eukaryotes. Production of oligosaccharides from marine algae using microb ial recombinant polysaccharidases is also of industrial interest as plants can be protected from infections by preincubation in the presence of approp riate signals that mimic the attacks by pathogens.