title: Development of a recombinant d-mannose isomerase and its characterizations for d-mannose synthesis.
abstract: d-Mannose isomerase (MIase) catalyzes the conversion of d-fructose to d-mannose. In this study, the MIase encoding gene (yihS) from Escherichia coli BL21 contains an ORF of 1242bp, was cloned and expressed in Bacillus subtilis WB800. This heterologous expression resulted in a hexamer with a molecular weight of 274.5kDa and Tm of 61.4°C. Efficient MIase secretory expression by the robust recombinant B. subtilis was achieved with activity of 51.2U/ml (d-mannose forming). Its optimal temperature and pH were 45.0°C and 7.0, respectively. Using d-fructose as the substrate, Km, kcat and catalytic efficiency value of kinetic reaction were 203.7±6.7mM, 27.7±0.7s(-1) and 136.0±2.9M(-1)s(-1), respectively. The production of d-mannose reached about 150g/l with approximately 25% turnover yield under the optimum conditions. These results demonstrated that B. subtilis was a promising candidate of MIase expression system for d-mannose production.
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, PR China; Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, PR China.
authors.forename: Xing
authors.initials: X
authors.lastname: Hu
authors.affiliation: Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, PR China.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, PR China; Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, PR China.
authors.forename: Ming
authors.initials: M
authors.lastname: Miao
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, PR China; Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, PR China.
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, PR China; Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, PR China. Electronic address: bjiang@jiangnan.edu.cn.
authors.forename: Bo
authors.initials: B
authors.lastname: Jiang
mesh_terms: D019747:Aldose-Ketose Isomerases / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D001412:Bacillus subtilis / Q000201:enzymology / Q000235:genetics*; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000737:chemistry* / Q000201:enzymology; D029968:Escherichia coli Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D005632:Fructose / Q000378:metabolism*; D015870:Gene Expression; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008358:Mannose / Q000096:biosynthesis*; D016366:Open Reading Frames; D055503:Protein Multimerization; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D029968:Escherichia coli Proteins; D011994:Recombinant Proteins; D005632:Fructose; D019747:Aldose-Ketose Isomerases; C032728:mannose isomerase; D008358:Mannose
keywords: Biotransformation; Gene expression; d-mannose isomerase