title: An optimal glucose feeding strategy integrated with step-wise regulation of the dissolved oxygen level improves N-acetylglucosamine production in recombinant Bacillus subtilis.
abstract: In our previous work, a recombinant Bacillus subtilis strain for the microbial production of N-acetylglucosamine (GlcNAc) was constructed through modular pathway engineering. In this study, to enhance GlcNAc production, glucose feeding approaches and dissolved oxygen (DO) control methods in fed-batch culture were systematically investigated. We first studied the effects of different glucose feeding strategies, including exponential fed-batch culture, pulse fed-batch culture, constant rate fed-batch culture, and glucose control (5 g/L, 10 g/L, 15 g/L) fed-batch culture, on cell growth and GlcNAc synthesis. We found that GlcNAc production in glucose control (5 g/L) fed-batch culture reached 26.58 g/L, which was 3.10 times that in batch culture. Next, the effect of DO level (20%, 30%, 40%, and 50%) on GlcNAc production was investigated, and a step-wise DO control strategy (0-7 h, 30%; 7-15 h, 50%; 15-50 h, 40%; 50-72 h, 30%) was introduced. With the optimal glucose and DO control strategy, GlcNAc production reached 35.77 g/L, which was 4.17 times the production in batch culture without DO control.
authors.affiliation: Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, Wuxi 214122, China.
authors.forename: Yanqiu
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China.
authors.forename: Yanfeng
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China. Electronic address: lijianghua@jiangnan.edu.cn.
authors.forename: Jianghua
authors.initials: J
authors.lastname: Li
authors.affiliation: School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta 30332, USA.
authors.forename: Hyun-dong
authors.initials: HD
authors.lastname: Shin
authors.affiliation: Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, Wuxi 214122, China.
authors.forename: Guocheng
authors.initials: G
authors.lastname: Du
authors.affiliation: Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, Wuxi 214122, China. Electronic address: longliu@jiangnan.edu.cn.
authors.forename: Long
authors.initials: L
authors.lastname: Liu
authors.affiliation: Synergetic Innovation Center of Food Safety and Nutrition, Wuxi 214122, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Chen
mesh_terms: D000117:Acetylglucosamine / Q000378:metabolism*; D001412:Bacillus subtilis / Q000235:genetics* / Q000378:metabolism*; D061249:Batch Cell Culture Techniques; D001709:Biotechnology / Q000379:methods*; D005818:Genetic Engineering; D005947:Glucose / Q000378:metabolism*; D007700:Kinetics; D010100:Oxygen / Q000378:metabolism*; D011995:Recombination, Genetic / Q000235:genetics*
chemical_list: D005947:Glucose; D010100:Oxygen; D000117:Acetylglucosamine
keywords: Bacillus subtilis; Fed-batch culture; Glucose control; N-acetylglucosamine; Step-wise dissolved oxygen control