Galactose oxidase action on galactose containing glycolipids - a fluorescence method

M Fortelius, Peter Mattjus

    Research output: Contribution to journalArticleScientificpeer-review

    5 Citations (Scopus)

    Abstract

    Features that alter the glycolipid sugar headgroup accessibility at the membrane interface have been studied in bilayer lipid model vesicles using a fluorescence technique with the enzyme galactose oxidase. The effects on oxidation caused by variation in the hydrophobic moiety of galactosylceramide or the membrane environment for galactosylceramide, monogalactosyldiacylglycerol and digalactosyldiacylglycerol were studied. For this study we combined the galactose oxidase method for determining the oxidizability of galactose containing glycolipids, and the fluorescence method for determining enzymatic hydrogen peroxide production. Exposed galactose residues with a free hydroxymethyl group at position 6 in the headgroup of glycolipids were oxidized with galactose oxidase and subsequently the resultant hydrogen peroxide was determined by a combination of horseradish peroxidase and 10-acetyl-3,7-dihydroxyphenoxazine (Amplex Red). Amplex Red reacts with hydrogen peroxide in the presence of horseradish peroxidase with a 1:1 stoichiometry to form resorufin. With this coupled enzyme approach it is also possible to determine the galactolipid transbilayer membrane distribution (inside-outside) in bilayer vesicles.
    Original languageUndefined/Unknown
    Pages (from-to)103–110
    Number of pages8
    JournalChemistry and Physics of Lipids
    Volume142
    Issue number1-2
    DOIs
    Publication statusPublished - 2006
    MoE publication typeA1 Journal article-refereed

    Keywords

    • Amplex Red
    • DGDG
    • enzyme
    • galactosylceramide
    • membrane
    • MGDG
    • phosphatidylcholine
    • sphingomyelin
    • vesicle

    Cite this