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A crosslinked inclusion body process for sialic acid synthesis
Jozef Nahálka1, Alica Vikartovská, Eva Hrabárová
1Institute of Chemistry, Center for Glycomics, Slovak Academy of Sciences, Bratislava, Slovak Republic. nahalka@savba.sk
Journal of Biotechnology
|March 4, 2008
Summary
Recombinant proteins can be intentionally aggregated into active inclusion bodies for biocatalysis. This study immobilized active inclusion bodies for efficient sialic acid production, demonstrating a novel biotechnological approach.
Area of Science:
- Biotechnology
- Protein Engineering
- Enzyme Immobilization
Background:
- Recombinant protein aggregation into inclusion bodies is often unpredictable and considered waste.
- Inclusion bodies can retain physiological activity and be harnessed for biotechnological applications.
Purpose of the Study:
- To investigate the targeted aggregation of recombinant proteins into active inclusion bodies.
- To develop an immobilized biocatalyst using crosslinked inclusion bodies (CLIB) for sialic acid production.
Main Methods:
- N-terminally fusing sialic acid aldolase with a cellulose-binding module for directed aggregation.
- Entrapping aggregated inclusion bodies in alginate beads and crosslinking with glutaraldehyde.
- Utilizing flow calorimetry for on-line monitoring of repetitive batch sialic acid production.
Main Results:
- Sialic acid aldolase was quantitatively aggregated into active inclusion bodies.
- The immobilized biocatalyst (CLIB) demonstrated efficient and repetitive sialic acid production.
- Alkaline epimerization was optimized for substrate (N-acetyl-D-mannosamine) generation.
Conclusions:
- Targeted formation of active inclusion bodies is a viable strategy for enzyme immobilization.
- CLIB technology offers a promising method for sustainable biocatalysis and sialic acid production.
- This approach transforms perceived 'wasted' cellular material into a valuable biotechnological tool.
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