Abstract
Mannitol is a polyol that occurs in a wide range of living organisms, where it fulfills different physiological roles. Several pathways have been described for the metabolism of mannitol by bacteria, including the phosphoenolpyruvate-dependent phosphotransferase system (PST) and a M2DH-based catabolic pathway. The latter involves two enzymes, a mannitol-2-dehydrogenase (EC 1.1.1.67) and a fructokinase (EC 2.7.1.4), and has been identified in different bacteria, e.g., the marine Bacteroidetes Zobellia galactanivorans (Zg) which had recently gained interest to study the degradation of macroalgal polysaccharides. This protocol describes the biochemical characterization of a recombinant mannitol-2-dehydrogenase (M2DH) of Zobellia galactanivorans. The ZgM2DH enzyme catalyzes the reversible conversion of mannitol to fructose using NAD+ as a cofactor. ZgM2DH activity was assayed in both directions, i.e., fructose reduction and mannitol oxidation.Reversible reaction:D-mannitol + NAD+ ↔ D-fructose + NADH + H+
Keywords: Mannitol degradation, Mannitol-2-dehydrogenase, Flavobacteria, Zobellia galactanivorans
Materials and Reagents
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Acknowledgments
This protocol was performed by Groisillier et al. (2015). This work was supported by the French National Research Agency via the investment expenditure program IDEALG (ANR-1 0-BTBR-02). We also acknowledge funding from the Émergence-UPMC-2011 research program.
References
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