title: Production of squalene by squalene synthases and their truncated mutants in Escherichia coli.
abstract: Squalene is a precursor of thousands of bioactive triterpenoids and also has industrial value as a lubricant, health-promoting agent, and/or drop-in biofuel. To establish an efficient Escherichia coli-based system for squalene production, we tested two different squalene synthases and their mutants in combination with precursor pathways. By co-expressing a chimeric mevalonate pathway with human or Thermosynechococcus squalene synthase, E. coli accumulated squalene up to 230 mg/L or 55 mg/g-DCW in flask culture. We also determined that a significant truncation of squalene synthase at the C-terminus retains partial cellular activity. The squalene-producing strain described herein represents a convenient platform for gene discovery and the construction of the pathway toward natural and non-natural hopanoids/steroids.
authors.affiliation: Department of Applied Chemistry and Biotechnology, Chiba University, 1-33 Yayoi-cho, Inage, Chiba 263-8522, Japan.
authors.forename: Akinori
authors.initials: A
authors.lastname: Katabami
authors.affiliation: Department of Applied Chemistry and Biotechnology, Chiba University, 1-33 Yayoi-cho, Inage, Chiba 263-8522, Japan.
authors.forename: Ling
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Applied Chemistry and Biotechnology, Chiba University, 1-33 Yayoi-cho, Inage, Chiba 263-8522, Japan.
authors.forename: Miki
authors.initials: M
authors.lastname: Iwasaki
authors.affiliation: Department of Applied Chemistry and Biotechnology, Chiba University, 1-33 Yayoi-cho, Inage, Chiba 263-8522, Japan.
authors.forename: Maiko
authors.initials: M
authors.lastname: Furubayashi
authors.affiliation: Department of Applied Chemistry and Biotechnology, Chiba University, 1-33 Yayoi-cho, Inage, Chiba 263-8522, Japan.
authors.forename: Kyoichi
authors.initials: K
authors.lastname: Saito
authors.affiliation: Department of Applied Chemistry and Biotechnology, Chiba University, 1-33 Yayoi-cho, Inage, Chiba 263-8522, Japan; Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan. Electronic address: umeno@faculty.chiba-u.jp.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Umeno
mesh_terms: D002851:Chromatography, High Pressure Liquid; D000458:Cyanobacteria / Q000201:enzymology / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D013186:Farnesyl-Diphosphate Farnesyltransferase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D008798:Mevalonic Acid / Q000378:metabolism; D050505:Mutant Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D009154:Mutation / Q000235:genetics*; D013185:Squalene / Q000378:metabolism*; D013696:Temperature
chemical_list: D050505:Mutant Proteins; D013185:Squalene; D013186:Farnesyl-Diphosphate Farnesyltransferase; D008798:Mevalonic Acid
keywords: Bacterial production; Carotenoid; Mevalonate pathway; Squalene synthase; Triterpenoid