Biochemical genetics of nucleotide sugar interconversion reactions
1Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269-3125, USA. wdreiter@uconn.edu
Current Opinion in Plant Biology
|May 20, 2008
Summary
Researchers clarified nucleotide sugar interconversion pathways using metabolic flux analysis and enzyme assays. Plant enzymes expressed in yeast aid in understanding metabolic regulation and producing valuable compounds.
Area of Science:
- Biochemistry
- Metabolic Engineering
- Plant Biology
Background:
- Nucleotide sugar interconversion reactions are crucial but thermodynamically irreversible in vivo.
- Feedback inhibition is a common regulatory theme, yet some recombinant enzyme data remain challenging to interpret.
- Understanding these pathways is key for metabolic engineering and producing valuable compounds.
Purpose of the Study:
- To elucidate the enzymology and regulation of nucleotide sugar interconversion reactions.
- To clarify the significance of proposed alternate metabolic pathways.
- To advance the understanding of arabinosylated cell wall polysaccharide synthesis.
Main Methods:
- Metabolic flux analysis
- Enzyme assays
- Bioinformatics approaches
- Heterologous expression of plant enzymes in yeast
Main Results:
- The significance of several proposed alternate pathways was clarified.
- Expression of plant nucleotide sugar interconversion enzymes in yeast proved effective for studying metabolic regulation.
- Reversibly glycosylated proteins were identified as mutases interconverting UDP-L-arabinose forms.
Conclusions:
- Metabolic flux analysis, enzyme assays, and bioinformatics are powerful tools for studying complex metabolic pathways.
- Heterologous expression systems offer a viable approach for investigating enzyme function and metabolic regulation.
- The discovery of reversibly glycosylated proteins as mutases represents a significant advance in understanding polysaccharide synthesis.
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