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Rapid One-step Enzymatic Synthesis and All-aqueous Purification of Trehalose Analogues
Published on: February 17, 2017
Engineering trehalose synthesis in Lactococcus lactis for improved stress tolerance.
Ana Lúcia Carvalho1, Filipa S Cardoso, Andreas Bohn
1Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República-EAN, 2780-157 Oeiras, Portugal.
Applied and Environmental Microbiology
|April 26, 2011
Summary
Engineered Lactococcus lactis to produce trehalose, enhancing its tolerance to acid, cold, and heat stress. This trehalose synthesis strategy benefits dairy industry applications and oral drug delivery systems.
Area of Science:
- Microbiology
- Biotechnology
- Food Science
Background:
- Trehalose accumulation is a key cellular defense mechanism against various environmental stresses.
- Propionibacterium freudenreichii naturally accumulates trehalose under acid stress.
- Lactococcus lactis, a common dairy starter, benefits from improved stress tolerance.
Purpose of the Study:
- To engineer Lactococcus lactis for enhanced trehalose synthesis.
- To improve the acid tolerance of Lactococcus lactis.
- To evaluate the protective effects of trehalose against multiple stress conditions.
Main Methods:
- Genetic engineering of Lactococcus lactis using trePP, pgmB, and otsB genes.
- Trehalose synthesis and quantification in engineered strains.
- Assessment of strain viability under acid, cold, heat shock, and freeze-drying conditions.
Main Results:
- Engineered Lactococcus lactis synthesized trehalose, with yields up to 15% in resting cells.
- Intracellular trehalose reached ~170 mM, with significant extracellular accumulation.
- Trehalose-producing strains exhibited 5-10 fold higher survivability against acid (pH 3), cold (4°C), and heat (45°C) shock.
Conclusions:
- Trehalose synthesis significantly enhances Lactococcus lactis tolerance to acid, cold, and heat stresses.
- The engineered strains show potential for applications in the dairy industry and oral drug delivery.
- This study provides a foundation for developing robust, food-grade microbial strains.
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