Producing High-purity Trehalose From Maltose By Yarrowia Lipolytica Displaying Trehalose Synthase On The Cell Surface

An alternative strategy that integrated enzyme production,trehalose biotransformation and bioremoval in one bioreactor was developed in this study,thus simplifying the traditional procedures used for trehalose production.The trehalose synthase gene from thermophilic archaea Picrophilus torridus was first fused to the YlPir1 anchor gene and then inserted into the genome of Yarrowia lipolytica,thus yielding an engineered yeast strain.The trehalose yield reached 73% under optimal conditions.The thermal and pH stability of the displayed enzyme was improved compared to its free form purified from recombinant Escherichia coli.After biotransformation,the glucose byproduct and residual maltose were directly fermented to ethanol by a selected Saccharomyces cerevisiae strain.Ethanol can be separated by distillation,and high-purity trehalose can easily be obtained from the fermentation broth.Our results show that this one-pot procedure is an efficient approach to the economical production of trehalose from maltose.