title: Precise precursor rebalancing for isoprenoids production by fine control of gapA expression in Escherichia coli.
abstract: Biosynthesis of isoprenoids via the 1-deoxy-D-xylulose-5-phosphate (DXP) pathway requires equimolar glyceraldehyde 3-phosphate and pyruvate to divert carbon flux toward the products of interest. Here, we demonstrate that precursor balancing is one of the critical steps for the production of isoprenoids in Escherichia coli. First, the implementation of the synthetic lycopene production pathway as a model system and the amplification of the native DXP pathway were accomplished using synthetic constitutive promoters and redesigned 5'-untranslated regions (5'-UTRs). Next, fine-controlled precursor balancing was investigated by tuning phosphoenolpyruvate synthase (PpsA) or glyceraldehyde 3-phosphate dehydrogenase (GAPDH). The results showed that tuning-down of gapA improved the specific lycopene content by 45% compared to the overexpression of ppsA. The specific lycopene content in the strains with down-regulated gapA increased by 97% compared to that in the parental strain. Our results indicate that gapA is the best target for precursor balancing to increase biosynthesis of isoprenoids.
authors.affiliation: Department of Life Sciences, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Korea.
authors.forename: Juyoung
authors.initials: J
authors.lastname: Jung
authors.affiliation: Department of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Korea.
authors.forename: Jae Hyung
authors.initials: JH
authors.lastname: Lim
authors.affiliation: School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Korea.
authors.forename: Se Yeon
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Department of Chemical and Biological Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea.
authors.forename: Dae-Kyun
authors.initials: DK
authors.lastname: Im
authors.affiliation: School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Korea.
authors.forename: Joo Yeon
authors.initials: JY
authors.lastname: Seok
authors.affiliation: Department of Life Sciences, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Korea; School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Korea.
authors.forename: Seung-Jae V
authors.initials: SV
authors.lastname: Lee
authors.affiliation: Department of Chemical and Biological Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 02841, Korea.
authors.forename: Min-Kyu
authors.initials: MK
authors.lastname: Oh
authors.affiliation: Department of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Korea; School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Korea. Electronic address: gyjung@postech.ac.kr.
authors.forename: Gyoo Yeol
authors.initials: GY
authors.lastname: Jung
mesh_terms: D053898:Biosynthetic Pathways / Q000235:genetics*; D002338:Carotenoids / Q000378:metabolism*; D004926:Escherichia coli; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics*; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics*; D024861:Genetic Enhancement / Q000379:methods; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000235:genetics* / Q000378:metabolism; D000077276:Lycopene; D060847:Metabolic Engineering / Q000379:methods*; D053858:Metabolic Networks and Pathways / Q000235:genetics; D013729:Terpenes / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D029968:Escherichia coli Proteins; D013729:Terpenes; D002338:Carotenoids; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D000077276:Lycopene
keywords: G3P; Isoprenoid; Lycopene; Precursor balancing; gapA; ppsA