Enzymatic activity and substrate specificity of recombinant tomato β-galactosidases 4 and 5
| ISSN: | 1432-2048 0032-0935 |
|---|---|
| DOI: | 10.1007/s00425-008-0842-x |
| Přístupová URL adresa: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::3b03278169e07db29114fed8f09f4a0b https://doi.org/10.1007/s00425-008-0842-x |
| Rights: | CLOSED |
| Přírůstkové číslo: | edsair.doi.dedup.....3b03278169e07db29114fed8f09f4a0b |
| Autor: | Megumi Ishimaru, Andrew J. Mort, David L. Smith, Kenneth C. Gross |
| Rok vydání: | 2008 |
| Předmět: |
food.ingredient
Pectin Oligosaccharides Plant Science Biology Substrate Specificity Cell wall chemistry.chemical_compound food Solanum lycopersicum Enzyme Stability Genetics Phylogeny Fluorescent Dyes chemistry.chemical_classification Pyrenes Galactosidases Hydrolysis Temperature Galactose food and beverages Hydrogen-Ion Concentration beta-Galactosidase Recombinant Proteins Yeast carbohydrates (lipids) Xyloglucan Enzyme chemistry Biochemistry DNA glycosylase Biocatalysis Sequence Analysis |
| Zdroj: | Planta. 229:447-456 |
| ISSN: | 1432-2048 0032-0935 |
| DOI: | 10.1007/s00425-008-0842-x |
| Popis: | The open reading frames of tomato beta-galactosidase (TBG) 4 and 5 cDNAs were expressed in yeast, and the enzymes properties and substrate specificities were investigated. The two enzymes had peak activities between pH 4-4.5 and 37-45 degrees C. TBG4 specifically hydrolyzed beta-(1-->4) and 4-linked galactooligosaccharides. TBG5 had a strong preference to hydrolyze beta-(1-->3) and beta-(1-->6)-linked galactooligosaccharides. Exo-beta-galactanase activity of the TBG enzymes was measured by determining the release of galactosyl residues from native tomato cell wall fractions throughout fruit development and ripening. Both TBGs released galactose from all of the fractions and stages tested. TBG4 activity was highest using chelator soluble pectin and alkali soluble pectin at the turning stage of ripening. Using aminopyrene trisulfonate labeled substrates, TBG4 was the only enzyme with strong exo-beta-(1-->4)-galactanase activity on 5 mer or greater galactans. TBG4 and TBG5 were both able to degrade galactosylated rhamnogalacturonan. Neither enzyme was able to degrade galactosylated xyloglucan. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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