Publications

• Mannitol oxidase and polyol dehydrogenases in the digestive gland of gastropods: Correlations with phylogeny and diet.

  Lobo-da-Cunha A., Amaral-de-Carvalho D., Oliveira E., Alves A., Costa V., Calado G.

  Mannitol oxidase and polyol dehydrogenases are enzymes that convert polyalcohols into sugars. Mannitol oxidase was previously investigated in terrestrial snails and slugs, being also present in a few aquatic gastropods. However, the overall distribution of this enzyme in the Gastropoda was not kno ... >> More

  Mannitol oxidase and polyol dehydrogenases are enzymes that convert polyalcohols into sugars. Mannitol oxidase was previously investigated in terrestrial snails and slugs, being also present in a few aquatic gastropods. However, the overall distribution of this enzyme in the Gastropoda was not known. Polyol dehydrogenases are also poorly studied in gastropods and other mollusks. In this study, polyalcohol oxidase and dehydrogenase activities were assayed in the digestive gland of 26 species of gastropods, representing the clades Patellogastropoda, Neritimorpha, Vetigastropoda, Caenogastropoda and Heterobranchia. Marine, freshwater and terrestrial species, including herbivores and carnivores were analyzed. Ultrastructural observations were undertake in species possessing mannitol oxidase, in order to investigate the correlation between this enzyme and the presence of tubular structures known to be associated with it. Mannitol oxidase activity was detected in the digestive gland of herbivores from the clades Caenogastropoda and Heterobranchia, but not in any carnivores or in herbivores from the clades Patellogastropoda, Neritimorpha and Vetigastropoda. In most of the species used in this study, dehydrogenase activities were detected using both D-mannitol and D-sorbitol as substrates. Nevertheless, in some carnivores these activities were not detected with both polyalcohols. Ultrastructural observations revealed tubular structures in digestive gland cells of some species having mannitol oxidase activity, but they were not observed in others. Based on our results, we suggest that mannitol oxidase first occurred in a herbivorous or omnivorous ancestor of Apogastropoda, the clade formed by caenogastropods and heterobranchs, being subsequently lost in those species that shifted towards a carnivorous diet. << Less

  PLoS One 13:e0193078-e0193078(2018) [PubMed] [EuropePMC]

  This publication is cited by 2 other entries.

• Mannitol oxidase: partial purification and characterization of the membrane-bound enzyme from the snail Helix aspersa.

  Vorhaben J.E., Smith D.D. Jr., Campbell J.W.

  Mannitol oxidase, a membrane-bound oxidase has been purified 250-fold from snail digestive gland tissue. The activity is solubilized by a number of ionic, non-ionic, and zwitterionic detergents. Purification of the solubilized enzyme was by polyethylene glycol fractionation and column chromatograp ... >> More

  Mannitol oxidase, a membrane-bound oxidase has been purified 250-fold from snail digestive gland tissue. The activity is solubilized by a number of ionic, non-ionic, and zwitterionic detergents. Purification of the solubilized enzyme was by polyethylene glycol fractionation and column chromatography using anionic exchange resins, hydroxylapatite, and gel filtration. The enzyme is stabilized by glycerol and remains active for at least one week at -20 degrees. Hydrogen peroxide is the oxygen reduction product and a mannose/hydrogen peroxide stoichiometry of 0.86 was found. D-Arabinitol and D-mannitol were the most active substrates of those tested. Results with these and other substrates suggest that the configuration around carbons-2 and -4 is critical for binding and reactivity. The apparent Km for D-mannitol is 6 mM and for oxygen, 40 microM. The pH optimum for the enzyme is between 8 and 8.5 and the isoelectric point is 5.4-5.6. << Less

  Int J Biochem 18:337-344(1986) [PubMed] [EuropePMC]

  This publication is cited by 2 other entries.