title: Redirection of Metabolic Flux into Novel Gamma-Aminobutyric Acid Production Pathway by Introduction of Synthetic Scaffolds Strategy in Escherichia Coli.
abstract: In general, gamma-aminobutyric acid (GABA) pathway involves the decarboxylation of glutamate, which is produced from sugar by Corynebacterium fermentation. GABA can be used for the production of pharmaceuticals and functional foods. Due to the increasing demand of GABA, it is essential to create an effective alternative pathway for the GABA production. In this study, Escherichia coli were engineered to produce GABA from glucose via GABA shunt, which consists of succinate dehydrogenase, succinate-semialdehyde dehydrogenase, and GABA aminotransferase. The three enzymes were physically attached to each other through a synthetic scaffold, and the Krebs cycle flux was redirected to the GABA pathway. By introduction of synthetic scaffold, 0.75 g/l of GABA was produced from 10 g/l of glucose at 30 °C and pH 6.5. The inactivation of competing metabolic pathways provided 15.4 % increase in the final GABA concentration.
authors.affiliation: Department of Chemical Engineering, University of Ulsan, 93 Daehakro, Nam-gu, Ulsan, 680-749, Republic of Korea.
authors.forename: Van Dung
authors.initials: VD
authors.lastname: Pham
authors.affiliation: Department of Chemical Engineering, University of Ulsan, 93 Daehakro, Nam-gu, Ulsan, 680-749, Republic of Korea.
authors.forename: Sivachandiran
authors.initials: S
authors.lastname: Somasundaram
authors.affiliation: Department of Biotechnology & Bioengineering, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju, 500-757, Republic of Korea.
authors.forename: Seung Hwan
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Environmental Engineering and Energy, Myongji University, San 38-2, Nam-dong, Cheoin-gu, Yongin-si, Gyeonggido, 449-728, Republic of Korea.
authors.forename: Si Jae
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Department of Chemical Engineering, University of Ulsan, 93 Daehakro, Nam-gu, Ulsan, 680-749, Republic of Korea. shhong@ulsan.ac.kr.
authors.forename: Soon Ho
authors.initials: SH
authors.lastname: Hong
mesh_terms: D002952:Citric Acid Cycle; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D005285:Fermentation; D005947:Glucose / Q000378:metabolism; D018698:Glutamic Acid / Q000096:biosynthesis* / Q000235:genetics; D060847:Metabolic Engineering; D053858:Metabolic Networks and Pathways; D005680:gamma-Aminobutyric Acid / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid; D005947:Glucose
keywords: Gamma-aminobutyric acid; Glucose; Metabolic pathway; Recombinant DNA; Synthetic scaffold