One-Pot Multienzyme Synthesis of Rare Ketoses from Glycerol
1Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology , Jiangnan University , Wuxi , Jiangsu 214122 , People's Republic of China.
Journal of Agricultural and Food Chemistry
|January 22, 2020
Summary
This study presents a green enzymatic method for synthesizing rare ketoses from glycerol. The one-pot process efficiently produces rare sugars using readily available materials.
Area of Science:
- Biocatalysis
- Synthetic Chemistry
- Green Chemistry
Background:
- Rare ketoses are valuable carbohydrates with limited natural abundance.
- Efficient and scalable synthesis of rare ketoses remains a challenge.
- Previous methods required pre-synthesis of key intermediates like glycerol 3-phosphate and glyceraldehyde.
Purpose of the Study:
- To develop a facile, one-pot, multienzyme approach for synthesizing rare ketoses.
- To utilize glycerol as the sole carbon source for rare ketose production.
- To overcome limitations of previous synthetic strategies by in situ generation of intermediates.
Main Methods:
- Enzymatic cascade involving glycerol phosphorylation and oxidation to dihydroxyacetone phosphate (DHAP) and glyceraldehyde (GA).
- Stereospecific formation of d- or l-glyceraldehyde using alditol oxidase or horse liver alcohol dehydrogenase.
- DHAP-dependent aldolases employed for aldol adduct formation, yielding rare ketohexose phosphates.
- Phosphate recycling by the initial phosphorylation enzyme to release free rare sugars.
Main Results:
- Successful synthesis of rare ketoses from glycerol and d-/l-glyceraldehyde in a one-pot multienzyme system.
- Efficient in situ generation of key intermediates (DHAP and GA) from glycerol.
- Production of rare ketohexose phosphates with controlled stereoconfiguration and diastereomeric ratios.
- Demonstrated phosphate recycling for the release of free rare sugars.
Conclusions:
- A scalable (100 mg to g scale) and cost-effective method for rare ketose synthesis from glycerol is established.
- The developed approach exemplifies green synthesis through high carbon utilization and cofactor recycling.
- This work provides a sustainable solution for obtaining rare ketoses and their derivatives.
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