title: Construction of a novel expression system for use in Corynebacterium glutamicum.
abstract: Corynebacterium glutamicum is an important microorganism for production of amino acids in industrial fermentation. Suitable vectors are needed for metabolic engineering in C. glutamicum. Most available vectors used in C. glutamicum carry antibiotic resistant genes as a genetic labeling for rapid identification of recombinant strains, and antibiotics have to be added to maintain the vector when growing the cells. These vectors, though excellent for laboratory use, are not preferable choices for industry-scale fermentation. In this work, we developed a novel expression system for use in C. glutamicum, which do not require antibiotics when used for industrial fermentation. This system includes two vectors: the shuttle vector pJYW-4 for expression of genes and the vector pJYW-6 for deletion of the essential gene alr in C. glutamicum. The vector pJYW-4 contains a large multiple cloning site for cloning multiple genes and two selective markers: one is the kanamycin-resistant gene kan and the other is an essential gene alr. The selective marker kan facilitates molecular manipulation or fermentations in the laboratory, and the selection marker alr is good for use in industry-scale fermentation, allowing in vivo maintenance of the expression vector through auxotrophic complementation; therefore, the two selection markers in pJYW-4 make it useful for both laboratory research and industrial fermentation, and convenient to transfer valuable laboratory-developed strains into industrial production. This newly-constructed expression system was successfully used to increase L-valine production in C. glutamicum ATCC 14067, indicating its potential on developing amino acid-producing C. glutamicum strains.
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
authors.forename: Jinyu
authors.initials: J
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, Wuxi 214122, China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Industrial Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
authors.forename: Hailing
authors.initials: H
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
authors.forename: Yanzhen
authors.initials: Y
authors.lastname: Tan
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, Jiangnan University, Wuxi 214122, China. Electronic address: xiaoyuanwang@hotmail.com.
authors.forename: Xiaoyuan
authors.initials: X
authors.lastname: Wang
mesh_terms: D003001:Cloning, Molecular; D048230:Corynebacterium glutamicum / Q000235:genetics*; D056915:DNA Copy Number Variations; D004269:DNA, Bacterial / Q000235:genetics; D005285:Fermentation; D017353:Gene Deletion; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D005822:Genetic Vectors / Q000235:genetics*; D010957:Plasmids / Q000235:genetics*; D014633:Valine / Q000096:biosynthesis
chemical_list: D004269:DNA, Bacterial; D014633:Valine
keywords: Auxotrophic complementation expression system; Corynebacterium glutamicum; Metabolic engineering; Shuttle vector; l-valine production