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Updated: May 21, 2026
11:06
Structural Characterization of Mannan Cell Wall Polysaccharides in Plants Using PACE
Published on: October 16, 2017
Combining polysaccharide biosynthesis and transport in a single enzyme: dual-function cell wall glycan synthases
1Department of Crop Science, North Carolina State University, Raleigh,NC, USA.
Frontiers in Plant Science
|June 28, 2012
Summary
Extracellular polysaccharides are synthesized by enzymes with dual functions, coupling synthesis and transport across membranes. This review explores plant cell wall glycan synthases with these combined activities.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- Extracellular polysaccharides (EPS) are vital polymers synthesized across diverse species.
- EPS biosynthesis necessitates membrane transport, moving substrates from the cytosol to extracellular or lumenal spaces.
- Enzymes involved can have separate transporter and transferase activities, or possess dual functions.
Purpose of the Study:
- To review the structural characteristics of plant cell wall glycan synthases.
- To highlight enzymes that couple polysaccharide synthesis with membrane transport.
- To draw parallels with known dual-function enzymes in other organisms.
Main Methods:
- Literature review of existing research on polysaccharide biosynthesis.
- Analysis of structural features of plant cell wall glycan synthases.
- Comparative study of dual-function enzymes across different species.
Main Results:
- Many polysaccharide biosynthetic enzymes exhibit combined transporter and transferase activities.
- These dual-function enzymes utilize substrates on one membrane side and deposit products on the other.
- Plant cell wall glycan synthases share structural characteristics with these known dual-function enzymes.
Conclusions:
- Plant cell wall glycan synthases likely possess coupled synthesis-transport mechanisms.
- Understanding these dual-function enzymes is crucial for comprehending cell wall assembly.
- This review provides insights into the molecular mechanisms of EPS production.
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