Characterization of Redox Sensitive Brown Algal Mannitol-1-Phosphatases

Macroalgae (seaweeds) are key primary producers in marine coastal habitats and largely contribute to global ocean carbon fluxes. They also represent attractive renewable feedstock for the production of biofuels, food, feed, bioactive. Brown algae seaweeds that produce alginates fucose containing sulfated polysaccharides their cell wall laminarin mannitol storage. The availability genomes kelp Saccharina japonica filamentous Ectocarpus sp. paved way biochemical characterization recombinant enzymes involved polysaccharide carbohydrates synthesis, including, notably, mannitol. algal biosynthesis starts with conversion fructose-6-phospate into mannitol-1-phosphate (mannitol-1P), this intermediate is hydrolysed by a haloacid dehalogenase phosphatase (M1Pase) We report here second M1Pase (EsM1Pase1). Both M1Pases were redox-sensitive enzymes, EsM1Pase1 active only presence reducing agent. Such catalytic properties have not been observed any yet. EsM1Pases specific mannitol-1-P, contrast S. could act on other phosphorylated sugars. Finally, brown formed two well-supported clades, possible distinct subcellular localization physiological role(s) under diverse environmental conditions and/or life cycle stages.