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STA11, a Chlamydomonas reinhardtii locus required for normal starch granule biogenesis, encodes disproportionating enzyme. Further evidence for a function of alpha-1,4 glucanotransferases during starch granule biosynthesis in green algae.

Authors :
Wattebled F
Ral JP
Dauvillée D
Myers AM
James MG
Schlichting R
Giersch C
Ball SG
D'Hulst C
Source :
Plant physiology [Plant Physiol] 2003 May; Vol. 132 (1), pp. 137-45.
Publication Year :
2003

Abstract

In Chlamydomonas reinhardtii, the presence of a defective STA11 locus results in significantly reduced granular starch deposition displaying major modifications in shape and structure. This defect simultaneously leads to the accumulation of linear malto-oligosaccharides (MOS). The mutants of STA11 were showed to lack D-enzyme, a plant alpha-1,4 glucanotransferase analogous to the Escherichia coli amylomaltase. We have cloned and characterized both the cDNA and gDNA corresponding to the C. reinhardtii D-enzyme. We now report allele-specific modifications of the D-enzyme gene in the mutants of STA11. These allele-specific modifications cosegregate with the corresponding sta11 mutations, thereby demonstrating that STA11 encodes D-enzyme. MOS production and starch accumulation were investigated during day and night cycles in wild-type and mutant C. reinhardtii cells. We demonstrate that in the algae MOS are produced during starch biosynthesis and degraded during the phases of net polysaccharide catabolism.

Details

Language :
English
ISSN :
0032-0889
Volume :
132
Issue :
1
Database :
MEDLINE
Journal :
Plant physiology
Publication Type :
Academic Journal
Accession number :
12746519
Full Text :
https://doi.org/10.1104/pp.102.016527