title: Overexpression of succinyl-CoA synthase for poly (3-hydroxybutyrate-co-3-hydroxyvalerate) production in engineered Escherichia coli BL21(DE3).
abstract: OBJECTIVE
  This study aims to increase the 3-hydroxyvalerate (3HV) fraction in poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(HB-co-HV)] using succinyl-CoA synthase.
  
  
  RESULTS
  Escherichia coli YH090, a polyhydroxyalkonate (PHA)-producing strain, was further engineered for overexpression of succinyl-CoA synthase genes (sucCD), and examined for P(HB-co-HV) copolymer production in the presence of various precursor molecules using mixture analysis. Glycerol, succinate and propionate were screened as important factors for controlling intracellular PHA accumulation and monomer composition. Glycerol concentrations exerted the greatest influence on the overall biomass concentration and the intracellular PHA content, while propionate concentrations in the presence of succinate influenced the 3HV content of the copolymer. Mixture analysis also demonstrated that the engineered strain has the capacity to accumulate up to 80% of its cell dry weight (CDW) as PHA with a variable fraction of 3HV monomer (maximum of 72 wt %) depending on the controlled conditions.
  
  
  CONCLUSIONS
  Propionate is the principal precursor for 3HV monomer in P(HB-co-HV) biopolymer and its utilization requires conversion to propionyl-CoA. Engineered E. coli YHY99, overexpressing sucCD genes, leads to an increase of the succinyl-CoA pool, which enhances the conversion rate of propionate by providing a CoA supply to other acyltransferase enzymes that have a role in propionate utilization.
  
  
  CONCLUSIONS
  Engineered E. coli YHY99 was able to utilize propionate with a 4·5-fold increase in rate, as compared to the control strain, and resulted in the synthesis of a copolymer with high 3HV monomer content.
authors.affiliation: Department of Biological Engineering, College of Engineering, Konkuk University, Seoul, South Korea.
authors.forename: S K
authors.initials: SK
authors.lastname: Bhatia
authors.affiliation: Department of Biological Engineering, College of Engineering, Konkuk University, Seoul, South Korea.
authors.forename: D-H
authors.initials: DH
authors.lastname: Yi
authors.affiliation: Department of Biological Engineering, College of Engineering, Konkuk University, Seoul, South Korea.
authors.forename: H-J
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Biological Engineering, College of Engineering, Konkuk University, Seoul, South Korea.
authors.forename: J-M
authors.initials: JM
authors.lastname: Jeon
authors.affiliation: Department of Biological Engineering, College of Engineering, Konkuk University, Seoul, South Korea.
authors.forename: Y-H
authors.initials: YH
authors.lastname: Kim
authors.affiliation: Department of Biological Engineering, College of Engineering, Konkuk University, Seoul, South Korea.
authors.forename: G
authors.initials: G
authors.lastname: Sathiyanarayanan
authors.affiliation: Department of Biological Engineering, College of Engineering, Konkuk University, Seoul, South Korea.
authors.forename: H M
authors.initials: HM
authors.lastname: Seo
authors.affiliation: Department of Biological Engineering, College of Engineering, Konkuk University, Seoul, South Korea.
authors.forename: J H
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Biological Engineering, College of Engineering, Konkuk University, Seoul, South Korea.
authors.forename: J-H
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Biological and Chemical Engineering, Hongik University, Jochiwon, Sejong City, Korea.
authors.forename: K
authors.initials: K
authors.lastname: Park
authors.affiliation: Department of Bioengineering, University of Massachusetts Dartmouth, North Dartmouth, MA, USA.
authors.forename: C J
authors.initials: CJ
authors.lastname: Brigham
authors.affiliation: Department of Biological Engineering, College of Engineering, Konkuk University, Seoul, South Korea.|Institute for Ubiquitous Information Technology and Applications (CBRU), Konkuk University, Seoul, South Korea.
authors.forename: Y-H
authors.initials: YH
authors.lastname: Yang
mesh_terms: D020155:3-Hydroxybutyric Acid; D000214:Acyl Coenzyme A / Q000235:genetics / Q000378:metabolism*; D000217:Acyltransferases / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism*; D060847:Metabolic Engineering; D011091:Polyesters / Q000378:metabolism*; D011422:Propionates / Q000378:metabolism; D000094122:Polyhydroxybutyrates
chemical_list: D020155:3-Hydroxybutyric Acid; D000214:Acyl Coenzyme A; D000217:Acyltransferases; D011091:Polyesters; D011422:Propionates; C052620:poly(3-hydroxybutyrate)-co-(3-hydroxyvalerate); D000094122:Polyhydroxybutyrates; C009061:propionyl-coenzyme A; C012046:succinyl-coenzyme A
keywords: copolymer; glycerol; poly(3-hydroxybutyrate-co-3-hydroxyvalerate); propionate; succinyl-CoA synthase