Characterization of plastidial starch phosphorylase in Triticum aestivum L. endosperm
Starch phosphorylase (Pho) catalyses the reversible transfer of glucosyl units from glucose1-phosphate to the non-reducing end of an alpha-1,4-linked glucan chain. Two major isoforms of Pho exist in the plastid (Pho1) and cytosol (Pho2). In this paper it is proposed that Pho1 may play an important r...
| Veröffentlicht in: | Journal of plant physiology. - 1979. - 166(2009), 14 vom: 15. Sept., Seite 1465-78 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2009
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| Zugriff auf das übergeordnete Werk: | Journal of plant physiology |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Starch Phosphorylase EC 2.4.1.- |
| Zusammenfassung: | Starch phosphorylase (Pho) catalyses the reversible transfer of glucosyl units from glucose1-phosphate to the non-reducing end of an alpha-1,4-linked glucan chain. Two major isoforms of Pho exist in the plastid (Pho1) and cytosol (Pho2). In this paper it is proposed that Pho1 may play an important role in recycling glucosyl units from malto-oligosaccharides back into starch synthesis in the developing wheat endosperm. Pho activity was observed in highly purified amyloplast extracts prepared from developing wheat endosperms, representing the first direct evidence of plastidial Pho activity in this tissue. A full-length cDNA clone encoding a plastidial Pho isoform, designated TaPho1, was also isolated from a wheat endosperm cDNA library. The TaPho1 protein and Pho1 enzyme activity levels were shown to increase throughout the period of starch synthesis. These observations add to the growing body of evidence which indicates that this enzyme class has a role in starch synthesis in wheat endosperm and indeed all starch storing tissues |
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| Beschreibung: | Date Completed 02.11.2009 Date Revised 30.09.2020 published: Print-Electronic GENBANK: EU595762 Citation Status MEDLINE |
| ISSN: | 1618-1328 |
| DOI: | 10.1016/j.jplph.2009.05.004 |