title: Improvement of the ammonia assimilation for enhancing L-arginine production of Corynebacterium crenatum.
abstract: There are four nitrogen atoms in L-arginine molecule and the nitrogen content is 32.1%. By now, metabolic engineering for L-arginine production strain improvement was focused on carbon flux optimization. In previous work, we obtained an L-arginine-producing Corynebacterium crenatum SDNN403 (ARG) through screening and mutation breeding. In this paper, a strain engineering strategy focusing on nitrogen supply and ammonium assimilation for L-arginine production was performed. Firstly, the effects of nitrogen atom donor (L-glutamate, L-glutamine and L-aspartate) addition on L-arginine production of ARG were studied, and the addition of L-glutamine and L-aspartate was beneficial for L-arginine production. Then, the glutamine synthetase gene glnA and aspartase gene aspA from E. coli were overexpressed in ARG for increasing the L-glutamine and L-aspartate synthesis, and the L-arginine production was effectively increased. In addition, the L-glutamate supply re-emerged as a limiting factor for L-arginine biosynthesis. Finally, the glutamate dehydrogenase gene gdh was co-overexpressed for further enhancement of L-arginine production. The final strain could produce 53.2 g l-1of L-arginine, which was increased by 41.5% compared to ARG in fed-batch fermentation.
authors.affiliation: The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, Jiangsu, People's Republic of China.
authors.forename: Jing
authors.initials: J
authors.lastname: Guo
authors.affiliation: The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, Jiangsu, People's Republic of China.
authors.forename: Zaiwei
authors.initials: Z
authors.lastname: Man
authors.affiliation: The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, Jiangsu, People's Republic of China. raozhm@jiangnan.edu.cn.|State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, People's Republic of China. raozhm@jiangnan.edu.cn.
authors.forename: Zhiming
authors.initials: Z
authors.lastname: Rao
authors.affiliation: The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, Jiangsu, People's Republic of China.
authors.forename: Meijuan
authors.initials: M
authors.lastname: Xu
authors.affiliation: The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, Jiangsu, People's Republic of China.
authors.forename: Taowei
authors.initials: T
authors.lastname: Yang
authors.affiliation: The Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, Jiangsu, People's Republic of China.
authors.forename: Xian
authors.initials: X
authors.lastname: Zhang
authors.affiliation: School of Pharmaceutical Sciences, Jiangnan University, Wuxi, 214122, Jiangsu, People's Republic of China. zhenghxu@jiangnan.edu.cn.
authors.forename: Zhenghong
authors.initials: Z
authors.lastname: Xu
mesh_terms: D000641:Ammonia / Q000378:metabolism*; D001120:Arginine / Q000096:biosynthesis*; D001224:Aspartic Acid / Q000378:metabolism; D061249:Batch Cell Culture Techniques; D003352:Corynebacterium / Q000235:genetics / Q000378:metabolism*; D003470:Culture Media / Q000737:chemistry; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D005285:Fermentation; D005969:Glutamate Dehydrogenase / Q000235:genetics / Q000378:metabolism; D005974:Glutamate-Ammonia Ligase / Q000235:genetics / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism; D005973:Glutamine / Q000378:metabolism; D007218:Industrial Microbiology; D060847:Metabolic Engineering
chemical_list: D003470:Culture Media; D029968:Escherichia coli Proteins; D005973:Glutamine; D001224:Aspartic Acid; D018698:Glutamic Acid; D000641:Ammonia; D001120:Arginine; D005969:Glutamate Dehydrogenase; C081173:glutamine synthetase I; D005974:Glutamate-Ammonia Ligase
keywords: Ammonium assimilation; Aspartase; Corynebacterium crenatum; Glutamate dehydrogenase; Glutamine synthetase; L-arginine