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Hyaluronic acid production by recombinant Lactococcus lactis
Liang-Jung Chien1, Cheng-Kang Lee
1Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei, 106, Taiwan.
Applied Microbiology and Biotechnology
|September 7, 2007
Summary
Researchers engineered Lactococcus lactis to produce microbial hyaluronic acid (HA). Coexpressing HA synthase and UDP-GlcDH significantly increased HA yield by eightfold, enabling safe production of this valuable biopolymer.
Area of Science:
- Biotechnology
- Microbial Engineering
- Biopolymer Production
Background:
- Microbial hyaluronic acid (HA) is typically produced by pathogenic Streptococcus species.
- Developing safe and efficient production methods for HA is crucial for its widespread application.
Purpose of the Study:
- To engineer a generally recognized as safe (GRAS) Lactococcus lactis to produce hyaluronic acid.
- To enhance hyaluronic acid yield by coexpressing key enzymes using a controlled expression system.
Main Methods:
- Utilized the nisin-controlled expression (NICE) system in Lactococcus lactis.
- Coexpressed hyaluronic acid synthase and uridine diphosphate-glucose dehydrogenase (UDP-GlcDH) from Streptococcus equi subsp. zooepidemicus.
- Compared HA production in strains with HA synthase alone versus coexpression of both enzymes.
Main Results:
- A recombinant L. lactis strain (LL-NA) expressing only HA synthase produced low HA concentrations (0.08 g/l).
- Overexpression of UDP-GlcDH was feasible in the NICE system.
- Coexpression of UDP-GlcDH with HA synthase (LL-NAB strain) resulted in an eightfold increase in HA concentration (0.65 g/l), despite a slight decrease in growth rate.
Conclusions:
- Lactococcus lactis can be engineered for safe and efficient hyaluronic acid production.
- Coexpression of HA synthase and UDP-GlcDH is a viable strategy to significantly enhance HA yields.
- This approach offers a promising alternative for microbial hyaluronic acid manufacturing.
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