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Updated: Jul 4, 2026
05:49
Protein Engineering by Yeast Surface Display
Published on: November 29, 2024
Increased protein productivity from immobilized recombinant yeast
1Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22903-2442, USA.
Biotechnology and Bioengineering
|May 1, 1991
Summary
Immobilizing Saccharomyces cerevisiae yeast in gelatin beads significantly enhanced plasmid stability and alpha-amylase production compared to suspension cultures. This method offers improved biocatalyst performance for industrial applications.
Area of Science:
- Biotechnology
- Microbial Engineering
- Bioprocess Technology
Background:
- Saccharomyces cerevisiae strain Mc16/p520 harbors an unstable plasmid (p520) for wheat alpha-amylase production.
- Plasmid instability in microbial cultures can limit productivity and process efficiency.
Purpose of the Study:
- To investigate the impact of cell immobilization on plasmid stability and alpha-amylase productivity.
- To compare immobilized yeast in different bioreactor configurations (fluidized and packed beds) with suspension cultures.
Main Methods:
- Immobilization of Saccharomyces cerevisiae using gelatin beads and glutaraldehyde cross-linking.
- Continuous culture experiments in fluidized and packed bed bioreactors.
- Comparison of immobilized cells with non-immobilized suspension cultures.
Main Results:
- Immobilized yeast exhibited significantly increased plasmid stability during continuous culture.
- Suspension cultures demonstrated rapid plasmid loss, indicating instability.
- Immobilization led to higher specific and volumetric productivity of secreted alpha-amylase.
- Packed bed bioreactor configuration yielded the highest specific productivity.
Conclusions:
- Cell immobilization in gelatin beads enhances plasmid stability in Saccharomyces cerevisiae.
- Immobilization is a viable strategy to improve biocatalyst performance and alpha-amylase yield.
- Packed bed configuration is optimal for maximizing specific productivity in this system.
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