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Trehalose synthesis in Euglena gracilis (Euglenophyceae) occurs through an enzyme complex
(Wiley Blackwell Publishing, Inc, 2005-08)
The aim of this study was to isolate and characterize a trehalose-synthesizing enzyme from Euglena gracilis Klebs. After purification by anion exchange chromatography, gel filtration, isoelectric focusing, and native ...
Trehalose-6-phosphate synthase 1 is not the only active TPS in Arabidopsis thaliana
(Portland Press, 2015-03)
Trehalose metabolism is essential for normal growth and development in higher plants. It is synthesized in a two-step pathway catalyzed by trehalose-6-phosphate (Tre6P) synthase (TPS) and trehalose phosphatase. Arabidopsis ...
Trehalose metabolism in plants
(Wiley Blackwell Publishing, Inc, 2014-08)
Trehalose is a quantitatively important compatible solute and stress protectant in many organisms, including green algae and primitive plants. These functions have largely been replaced by sucrose in vascular plants, and ...
Allosteric regulation of the partitioning of glucose-1-phosphate between glycogen and trehalose biosynthesis in Mycobacterium tuberculosis
(Elsevier Science, 2015-01)
Background: Mycobacterium tuberculosis is a pathogenic prokaryote adapted to survive in hostile environments. In this organism and other Gram-positive actinobacteria, the metabolic pathways of glycogen and trehalose are ...
Feedback inhibition of starch degradation in Arabidopsis leaves mediated by trehalose 6-phosphate
(American Society of Plant Biologist, 2013-11)
Many plants accumulate substantial starch reserves in their leaves during the day and remobilize them at night to provide carbon and energy for maintenance and growth. In this paper, we explore the role of a sugar-signaling metabolite, trehalose-6-phosphate (Tre6P), in regulating the accumulation and turnover of transitory starch in Arabidopsis (Arabidopsis thaliana) leaves. Ethanol-induced overexpression of trehalose-phosphate synthase during the day increased Tre6P levels up to 11-fold. There was a transient increase in the rate of starch accumulation in the middle of the day, but this was not linked to reductive activation of ADP-glucose pyrophosphorylase. A 2- to 3-fold increase in Tre6P during the night led to significant inhibition of starch degradation. Maltose and maltotriose did not accumulate, suggesting that Tre6P affects an early step in the pathway of starch degradation in the chloroplasts. Starch granules isolated from induced plants had a higher orthophosphate content than granules from noninduced control plants, consistent either with disruption of the phosphorylation-dephosphorylation cycle that is essential for efficient starch breakdown or with inhibition of starch hydrolysis by beta-amylase. Nonaqueous fractionation of leaves showed that Tre6P is predominantly located in the cytosol, with estimated in vivo Tre6P concentrations of 4 to 7 µM in the cytosol, 0.2 to 0.5 µM in the chloroplasts, and 0.05 µM in the vacuole. It is proposed that Tre6P is a component in a signaling pathway that mediates the feedback regulation of starch breakdown by sucrose, potentially linking starch turnover to demand for sucrose by growing sink organs at night....
A Tale of Two Sugars: Trehalose 6-Phosphate and Sucrose
(American Society of Plant Biologist, 2016-09)
Trehalose 6-phosphate (Tre6P), the intermediate of trehalose biosynthesis, is an essential signal metabolite in plants, linking growth and development to carbon status. The Suc-Tre6P nexus model postulates that Tre6P is ...
The production and utilization of GDP-glucose in the biosynthesis of trehalose-6-phosphate by Streptomyces venezuelae
(American Society for Biochemistry and Molecular Biology, 2017-01)
Trehalose-6-phosphate synthase OtsA from streptomycetes is unusual in that it uses GDP-glucose as the donor substrate rather than the more commonly used UDP-glucose. We now confirm that OtsA from Streptomyces venezuelae ...
The production and utilization of GDP-glucose in the biosynthesis of trehalose 6-phosphate by streptomyces venezuelae
(American Society for Biochemistry and Molecular Biology, 2017-01)
Trehalose-6-phosphate synthase OtsA from streptomycetes is unusual in that it uses GDP-glucose as the donor substrate rather than the more commonly used UDP-glucose. We now confirm that OtsA from Streptomyces venezuelae ...