Partial Purification, Photoaffinity Labeling, and Properties of Mung Bean UDP-Glucose:Dolicholphosphate Glucosyltransferase
| العنوان: | Partial Purification, Photoaffinity Labeling, and Properties of Mung Bean UDP-Glucose:Dolicholphosphate Glucosyltransferase |
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| المؤلفون: | Richard R. Drake, Alan D. Elbein, Irena Pastuszak, Gur P. Kaushal |
| المصدر: | Plant Physiology. 97:396-401 |
| بيانات النشر: | Oxford University Press (OUP), 1991. |
| سنة النشر: | 1991 |
| مصطلحات موضوعية: | chemistry.chemical_classification, biology, Photoaffinity labeling, Physiology, Substrate (chemistry), Plant Science, biology.organism_classification, Enzyme assay, carbohydrates (lipids), chemistry.chemical_compound, Enzyme, Biochemistry, Biosynthesis, chemistry, Glycosyltransferase, Genetics, biology.protein, Glucosyltransferase, Phaseolus |
| الوصف: | UDP-glucose:dolichylphosphate glucosyltransferase has been purified 734-fold from Triton X-100 solubilized mung bean (Phaseolus aureus) microsomes. The partially purified enzyme has broad pH optima of activity from 6.0 to 7.0 and is maximally stimulated with 10 millimolar MgCl2. The Km for UDP-glucose was determined as 27 micromolar, and the Km for dolichol-P was 2 micromolar. Using the UDP-glucose photoaffinity analog, 5-azido-UDP-glucose, a polypeptide of 39 kilodaltons on sodium dodecyl sulfate-polyacrylamide gels was identified as the catalytic subunit of the enzyme. Photoinsertion into this 39-kilodalton polypeptide with [32P]5-azido-UDP-glucose was saturable, and was maximally protected with the native substrate UDP-glucose. 5-Azido-UDP-glucose behaves competitively with UDP-glucose in enzyme assays, and upon photolysis inhibits activity in proportion to its concentration. This study represents the first subunit identification of a plant glycosyltransferase involved in the biosynthesis of the lipid-linked oligosaccharides that are precursors of N-linked glycoproteins. |
| تدمد: | 1532-2548 0032-0889 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_________::61ef2039e912863cfbd8602eef4cbff7Test https://doi.org/10.1104/pp.97.1.396Test |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.doi...........61ef2039e912863cfbd8602eef4cbff7 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 15322548 00320889 |
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