Synthesis of Floridean Starch in the Red Alga Gracilaria Gracilis Occurs Via ADP-Glucose
In higher plants and green algae starch is the major product of photosynthesis (1). The route conducting to polysaccharide synthesis in these organisms has been well characterized, taking place by utilizing ADPGk as the glucosyl donor (for reviews see 1–3). Moreover, ADPG1c pyrophosphorylase (AGP; EC 220.127.116.11), the enzyme catalyzing the production of the sugar nucleotide in the presence of a divalent metal ion (Mg2+):
is the key regulatory enzyme in the biosynthetic pathway (1–4). AGP from higher plants, green algae and cyanobacteria is allosterically regulated by 3P-glycerate (3PGA, activator) and Pi (inhibitor). It has been clearly demonstrated that the amount of starch accumulated depends upon the fine regulation of the enzyme by these metabolites (4).
Key wordsalgae C partitioning enzymes polysaccharides red algae starch
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- 1.Iglesias, A.A. and Podestd, F.E. (1996) In: Handbook of Photosynthesis (M. Pessarakli, ed.) pp. 681–698. Marcel Dekker, New York.Google Scholar
- 2.Preiss, J. (1991) In: Oxford Surveys of Plant Molecular and Cell Biology (J. Miflin, ed.) pp. 59–114. Oxford Univ. Press, Oxford.Google Scholar
- 5.Yu, S. (1992) Ph Thesis, Uppsala University, Uppsala, Sweden.Google Scholar
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