Recombinant Production of Thermostable Trehalose Synthase Expression in Escherichia coli Nissle 1917

• Main Authors: SU,PO-CHANG, 蘇柏彰
• Other Authors: CHEN,PO-TING
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/357bg6

碩士 === 南臺科技大學 === 生物科技系 === 106 === Trehalose is a nonreducing disaccharide formed by an α,α-1,1-glycosidic bond between two glucose molecules.Its sources include bacteria, yeast, fungi, insects, invertebrates, and plants, and it exhibits important biological functions in organisms, such as providing a source of energy and carbon and protecting organisms against environmental stresses such as drought, freezing, high temperature, and high salinity. These properties have broadened the application value of trehalose in the food, cosmetics, and pharmaceutical industries. Trehalose synthase converts maltose into trehalose in a single step through an intramolecular conversion reaction. Maltose is a cost-effective and easily obtained substrate that has great potential for industrial production of trehalose using trehalose synthase. Escherichia coli Nissle 1917 is classified as a probiotic and does not have endotoxins, in contrast to other E. coli strains; therefore, developing it as a host for expressing recombinant proteins would have high applicability. The present study constructed the T7 expression system in E. coli Nissle 1917 and used it to express recombinant thermostable trehalose synthase. In addition, the difference between this system and the pET system was evaluated, and this recombinant enzyme was used for trehalose biosynthesis. In addition, to achieve enzyme immobilization, we attached a chitin-binding domain (ChBD) gene to the N-terminus or the C-terminus of the trehalose synthase gene and evaluated the efficacy of enzyme immobilization. The results showed that using E. coli Nissle 1917 as an expression host for biosynthesis of thermostable trehalose synthase and constructing a trehalose conversion process have great potential for commercial development.