title: Identification of bottlenecks in Escherichia coli engineered for the production of CoQ(10).
abstract: In this work, Escherichia coli was engineered to produce a medically valuable cofactor, coenzyme Q(10) (CoQ(10)), by removing the endogenous octaprenyl diphosphate synthase gene and functionally replacing it with a decaprenyl diphosphate synthase gene from Sphingomonas baekryungensis. In addition, by over-expressing genes coding for rate-limiting enzymes of the aromatic pathway, biosynthesis of the CoQ(10) precursor para-hydroxybenzoate (PHB) was increased. The production of isoprenoid precursors of CoQ(10) was also improved by the heterologous expression of a synthetic mevalonate operon, which permits the conversion of exogenously supplied mevalonate to farnesyl diphosphate. The over-expression of these precursors in the CoQ(10)-producing E. coli strain resulted in an increase in CoQ(10) content, as well as in the accumulation of an intermediate of the ubiquinone pathway, decaprenylphenol (10P-Ph). In addition, the over-expression of a PHB decaprenyl transferase (UbiA) encoded by a gene from Erythrobacter sp. NAP1 was introduced to direct the flux of DPP and PHB towards the ubiquinone pathway. This further increased CoQ(10) content in engineered E. coli, but decreased the accumulation of 10P-Ph. Finally, we report that the combined over-production of isoprenoid precursors and over-expression of UbiA results in the decaprenylation of para-aminobenzoate, a biosynthetic precursor of folate, which is structurally similar to PHB.
authors: Department of Biology, Concordia University, 7141 Sherbrooke West, Montréal, Québec, Canada.
authors: Corinne P
authors: CP
authors: Cluis
authors: Andrew
authors: A
authors: Ekins
authors: Lauren
authors: L
authors: Narcross
authors: Heng
authors: H
authors: Jiang
authors: Nicholas D
authors: ND
authors: Gold
authors: Adam M
authors: AM
authors: Burja
authors: Vincent J J
authors: VJ
authors: Martin
mesh_terms: D010129:4-Aminobenzoic Acid / Q000378:metabolism; D019883:Alkyl and Aryl Transferases / Q000235:genetics; D004122:Dimethylallyltranstransferase / Q000096:biosynthesis; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D017353:Gene Deletion; D005818:Genetic Engineering; D008798:Mevalonic Acid / Q000378:metabolism; D010226:Parabens / Q000378:metabolism; D010636:Phenols / Q000378:metabolism; D011106:Polyisoprenyl Phosphates / Q000096:biosynthesis; D011401:Promoter Regions, Genetic; D012717:Sesquiterpenes; D042301:Sphingomonadaceae / Q000201:enzymology / Q000235:genetics; D020578:Sphingomonas / Q000235:genetics / Q000378:metabolism; D013729:Terpenes / Q000378:metabolism; D014451:Ubiquinone / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D010226:Parabens; D010636:Phenols; D011106:Polyisoprenyl Phosphates; D012717:Sesquiterpenes; D013729:Terpenes; D014451:Ubiquinone; C004808:farnesyl pyrophosphate; D019883:Alkyl and Aryl Transferases; C039821:decaprenyl pyrophosphate synthetase; C048987:octaprenyl pyrophosphate synthetase; C509554:4-hydroxybenzoic acid oligoprenyltransferase, E coli; D004122:Dimethylallyltranstransferase; C024989:coenzyme Q10; C038193:4-hydroxybenzoic acid; D008798:Mevalonic Acid; D010129:4-Aminobenzoic Acid