title: Efficient production of D-tagatose using a food-grade surface display system.
abstract: D-tagatose, a functional sweetener, is commonly transformed from D-galactose by L-arabinose isomerase (L-AI). In this study, a novel type of biocatalyst, L-AI from Lactobacillus fermentum CGMCC2921 displayed on the spore surface of Bacillus subtilis 168, was developed for producing D-tagatose. The anchored L-AI, exhibiting the relatively high bioactivity, suggested that the surface display system using CotX as the anchoring protein was successfully constructed. The stability of the anchored L-AI was significantly improved. Specifically, the consolidation of thermal stability representing 87% of relative activity was retained even at 80 °C for 30 min, which remarkably favored the production of D-tagatose. Under the optimal conditions, the robust spores can convert 75% D-galactose (100 g/L) into D-tagatose after 24 h, and the conversion rate remained at 56% at the third cycle. Therefore, this biocatalysis system, which could express the target enzyme on the food-grade vector, was an alternative method for the value-added production of D-tagatose.
authors: State Key Laboratory of Materials-Oriented Chemical Engineering, College of Food Science and Light Industry, Nanjing University of Technology , 30 Puzhu South Road, Nanjing 211816, People's Republic of China.
authors: Yi
authors: Y
authors: Liu
authors: Sha
authors: S
authors: Li
authors: Hong
authors: H
authors: Xu
authors: Lingtian
authors: L
authors: Wu
authors: Zheng
authors: Z
authors: Xu
authors: Jing
authors: J
authors: Liu
authors: Xiaohai
authors: X
authors: Feng
mesh_terms: D019747:Aldose-Ketose Isomerases / Q000378:metabolism*; D001412:Bacillus subtilis; D001426:Bacterial Proteins; D055162:Biocatalysis; D005690:Galactose / Q000378:metabolism; D006601:Hexoses / Q000096:biosynthesis*; D052197:Limosilactobacillus fermentum / Q000201:enzymology; D011994:Recombinant Proteins; D013171:Spores, Bacterial; D013549:Sweetening Agents
chemical_list: D001426:Bacterial Proteins; D006601:Hexoses; D011994:Recombinant Proteins; D013549:Sweetening Agents; C081620:cotX protein, Bacillus subtilis; D019747:Aldose-Ketose Isomerases; C019715:L-arabinose isomerase; C030192:tagatose; D005690:Galactose