title: Metabolic engineering of a novel Klebsiella oxytoca strain for enhanced 2,3-butanediol production.
abstract: Fermentative 2,3-butanediol (2,3-BD) production has been receiving increasing interest for its potential as a platform chemical intended for the production of synthetic rubbers, plastics, and solvents. In this study, Klebsiella oxytoca GSC 12206, a 2,3-BD native hyper-producing and nonpathogenic bacterium, was isolated from a cattle farm. Since this isolate produced a significant amount of lactic acid along with 2,3-BD, its mutant deficient in lactic acid formation was constructed by disrupting the ldhA gene which encodes lactate dehydrogenase. The ldhA gene was deleted precisely by using the pKGS plasmid. When compared to the wild-type strain, the mutant deleted with the ldhA gene in glucose fermentation resulted in an increase of 54%, 13%, 60%, and 78% of 2,3-BD titer, productivity, yield, and selectivity, respectively. A fed-batch fermentation by this mutant with intermittent glucose feeding produced 115 g/L of 2,3-BD with an yield and productivity of 0.41 g 2,3-BD per g glucose and 2.27 g/L h, respectively, indicating the usefulness for the industrial production of 2,3-BD.
authors: Research and Development Center, GS Caltex Corporation, 104-4 Munji-dong, Yuseong-gu, Daejeon 305-380, Republic of Korea.
authors: Duk-Ki
authors: DK
authors: Kim
authors: Chelladurai
authors: C
authors: Rathnasingh
authors: Hyohak
authors: H
authors: Song
authors: Hee Jong
authors: HJ
authors: Lee
authors: Doyoung
authors: D
authors: Seung
authors: Yong Keun
authors: YK
authors: Chang
mesh_terms: D000818:Animals; D002072:Butylene Glycols / Q000378:metabolism*; D002417:Cattle; D005285:Fermentation; D005947:Glucose / Q000378:metabolism; D041121:Klebsiella oxytoca / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D007770:L-Lactate Dehydrogenase / Q000235:genetics; D019344:Lactic Acid / Q000378:metabolism; D060847:Metabolic Engineering
chemical_list: D002072:Butylene Glycols; D019344:Lactic Acid; C026978:2,3-butylene glycol; D007770:L-Lactate Dehydrogenase; D005947:Glucose