title: Engineering of carboligase activity reaction in Candida glabrata for acetoin production.
abstract: Utilization of Candida glabrata overproducing pyruvate is a promising strategy for high-level acetoin production. Based on the known regulatory and metabolic information, acetaldehyde and thiamine were fed to identify the key nodes of carboligase activity reaction (CAR) pathway and provide a direction for engineering C. glabrata. Accordingly, alcohol dehydrogenase, acetaldehyde dehydrogenase, pyruvate decarboxylase, and butanediol dehydrogenase were selected to be manipulated for strengthening the CAR pathway. Following the rational metabolic engineering, the engineered strain exhibited increased acetoin biosynthesis (2.24 g/L). In addition, through in silico simulation and redox balance analysis, NADH was identified as the key factor restricting higher acetoin production. Correspondingly, after introduction of NADH oxidase, the final acetoin production was further increased to 7.33 g/L. By combining the rational metabolic engineering and cofactor engineering, the acetoin-producing C. glabrata was improved stepwise, opening a novel pathway for rational development of microorganisms for bioproduction.
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; The Laboratory of Food Microbial-Manufacturing Engineering, Jiangnan University, Wuxi 214122, China.
authors.forename: Shubo
authors.initials: S
authors.lastname: Li
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; The Laboratory of Food Microbial-Manufacturing Engineering, Jiangnan University, Wuxi 214122, China.
authors.forename: Nan
authors.initials: N
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China; The Laboratory of Food Microbial-Manufacturing Engineering, Jiangnan University, Wuxi 214122, China. Electronic address: mingll@jiangnan.edu.cn.
authors.forename: Liming
authors.initials: L
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; The Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Chen
mesh_terms: D000093:Acetoin / Q000378:metabolism*; D041221:Candida glabrata / Q000201:enzymology / Q000235:genetics; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D060847:Metabolic Engineering / Q000379:methods*; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism; D019289:Pyruvic Acid / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D019289:Pyruvic Acid; D000093:Acetoin; D010088:Oxidoreductases
keywords: Acetoin; Candida glabrata; Cofactor engineering; In silico; Metabolic engineering