1. Identification of a novel recombinant D-lyxose isomerase from Thermoprotei archaeon with high thermostable, weak-acid and nickel ion dependent properties.
- Author
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Wu H, Chen M, Guang C, Zhang W, and Mu W
- Subjects
- Buffers, Cloning, Molecular, Crystallization, Escherichia coli metabolism, Fructose chemistry, Hydrogen-Ion Concentration, Ions, Kinetics, Mannose chemistry, Molecular Weight, Pentoses chemistry, Phosphates, Phylogeny, Substrate Specificity, Temperature, Aldose-Ketose Isomerases biosynthesis, Archaea enzymology, Nickel chemistry, Recombinant Proteins biosynthesis
- Abstract
Recently, production of D-mannose becomes a hotspot owing to it exhibiting many physiological functions on people's health and wide applications in food and pharmaceutical field. The use of biological enzymes to production of D-mannose is of particular receiving considerable concerns due to it possessing many merits over chemical synthesis and plant extraction strategies. D-Lyxose isomerase (D-LIase) plays a pivotal role in preparation of D-mannose from d-fructose through isomerization reaction. Thus, a novel putative D-LIase from thermophiles strain Thermoprotei archaeon which was expressed in E. coli BL21(DE3) was first identified and biochemically characterized. The recombinant D-LIase showed an optimal temperature of 80 and 85 °C and pH of 6.5. It was highly thermostable at 70 °C and 80 °C after incubating for 48 h and 33 h, respectively, with retaining over 50% of the initial activity. A lower concentration of Ni
2+ (0.5 mM) could greatly increase the activity by 25-fold, which was rare reported in other D-LIases. It was a dimer structure with melting temperature of 88.3 °C. Under the optimal conditions, 15.8 g L-1 of D-mannose and 33.8 g L-1 of D-xylulose were produced from 80 g L-1 of d-fructose and D-lyxose, respectively. This work provided a promising candidate sugar isomerase T. archaeon D-LIase for the production of D-mannose and D-xylulose., (Copyright © 2020 Elsevier B.V. All rights reserved.)- Published
- 2020
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