Nejvíce citovaný článek - PubMed ID 689573
Glucose-2-oxidase activity and accumulation of D-arabino-2-hexosulose in cultures of the basidiomycete Oudemansiella mucida
The ultrastructural distribution of the sugar-oxidizing enzyme pyranose 2-oxidase (POD) in hyphae of Phanerochaete chrysosporium K-3 grown under liquid culture conditions optimal for the enzyme's production was studied by transmission electron microscopy immunocytochemistry. Using the 3-dimethylaminobenzoic acid-3-methyl-2-benzothiazolinone hydrazone hydrochloride H(2)O(2) peroxidase spectrophotometric assay, POD was detected in mycelial extracts from days 7 to 18, with maximum activity recorded on day 12. Onset of POD activity occurred in the secondary phase of hyphal development at a time of stationary growth, glucose limitation, and pH increase. POD was also detected extracellularly in the culture fluid from days 7 to 18, with maximum activity recorded on day 13. At early stages of development (3 to 4 days), using anti-POD antibodies and immunogold labeling, POD was localized in multivesicular and electron-dense bodies and in cell membrane regions. After 10 to 12 days of growth, at maximum POD activity, POD was concentrated within the periplasmic space where it was associated with membrane-bound vesicles and other membrane structures. At later stages of development (17 to 18 days), when the majority of hyphae were lysed, POD was observed associated with residual intracellular membrane systems and vesicles. Transmission electron microscopy immunocytochemical studies also demonstrated an extracellular distribution of the enzyme at the stationary growth phase, showing its association with fungal extracellular slime. In studies of ligninolytic cultures of the same fungus, POD was found to have a similar intracellular and extracellular distribution in slime as that recorded for cultures grown with cornsteep. POD's peripheral cytoplasmic distribution shows similarities to the cellular distribution of that reported previously for H(2)O(2)-dependent lignin and manganese peroxidases in P. chrysosporium.
- Publikační typ
- časopisecké články MeSH
The activity of intracellular glucose-2-oxidase was tested in 40 species of 26 basidiomycete genera. The enzyme catalyzing the oxidation of D-glucose to the dicarbonyl sugar D-arabino-2-hexosulose was demonstrated in mycelial extracts of 9 species of Aphyllophorales and 6 species of Agaricales cultivated in liquid media. In the majority of species exhibiting this activity hexosulose was detected in the cultivation medium. The highest enzyme activity was detected in Oudemansiella mucida, Coriolopsis occidentalis, Fomes fomentarius, Trametes versicolor and a not-yet-classified species of the genus Trametes.
Quantitative gas chromatography was used to determine soluble neutral sugars in an extract of the fungus Oudemansiella mucida grown on a synthetic glucose medium. Apart from the usual fungal sugar components, viz. trehalose, D-glucose, D-mannitol, D-arabinitol, glycerol and inositol, the 6-day-old mycelium contained D-arabino-2-hexosulose (D-glucosone). In the period of maximum growth, this aldoketose was the predominant monosaccharide (3.4% mycelial dry weight).
- MeSH
- Basidiomycota metabolismus MeSH
- chromatografie plynová MeSH
- cukerné alkoholy metabolismus MeSH
- glukosa metabolismus MeSH
- glycerol metabolismus MeSH
- inositol metabolismus MeSH
- mannitol metabolismus MeSH
- papírová chromatografie MeSH
- trehalosa metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- cukerné alkoholy MeSH
- glukosa MeSH
- glycerol MeSH
- inositol MeSH
- mannitol MeSH
- trehalosa MeSH
