title: Enhanced free fatty acid production by codon-optimized Lactococcus lactis acyl-ACP thioesterase gene expression in Escherichia coli using crude glycerol.
abstract: Fatty acid production and composition are determined by the type of acyl-acyl carrier protein thioesterases (acyl-ACP TEs) expressed in Escherichia coli. Bacterial acyl-ACP TEs from Lactococcus lactis (SGJS47), Enterococcus faecalis (SGJS49), and Burkholderia cepacia (SGJS50) were codon-optimized and expressed in E. coli for enhanced fatty acid production. Samples were extracted at the lag, log, and stationary phases of cell growth, and gene expression levels of the codon optimized acy-ACP TEs as well as fatty acid production were monitored. At 24h after initiation of gene expression, the OPLlTE expression level and fatty acid production in SGJS47 increased up to 15.8-fold and 3.2-fold compared to the control and other recombinant strains, respectively. Additionally, in SGJS47, improvement in free fatty acid (FFA) composition, high-specificity production of short-chain fatty acids (C8, C10) and unsaturated fatty acids (C16:1) was achieved in crude glycerol medium condition. Compared with control strain, the percentage of FFAs (C8 and C10) was enhanced by approximately 16- to 21-fold, C16:1 FFA ratio increased approximately 18-fold. Observation of codon-optimized acyl-ACP TE genes expression level in E. coli may be useful for understanding mechanisms towards improving fatty acid production. Engineered strains have the potential to overproduce specific FFAs and thereby reduce the cost of fatty acid production by using industrially inexpensive carbon sources.
authors.affiliation: Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 121-742, Republic of Korea.
authors.forename: Sunhee
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 121-742, Republic of Korea.
authors.forename: Soohyun
authors.initials: S
authors.lastname: Park
authors.affiliation: Department of Chemical Engineering, Kwangwoon University, Seoul 139-701, Republic of Korea.
authors.forename: Chulhwan
authors.initials: C
authors.lastname: Park
authors.affiliation: Department of Biotechnology and Bioinformatics, Korea University, Jochiwon, Chungnam 339-800, Republic of Korea.
authors.forename: Seung Pil
authors.initials: SP
authors.lastname: Pack
authors.affiliation: Department of Chemical and Biomolecular Engineering, Sogang University, Seoul 121-742, Republic of Korea. Electronic address: jinwonlee@sogang.ac.kr.
authors.forename: Jinwon
authors.initials: J
authors.lastname: Lee
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism*; D001483:Base Sequence; D056804:Biofuels / Q000382:microbiology; D016956:Burkholderia cepacia / Q000201:enzymology / Q000235:genetics; D003062:Codon / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D013293:Enterococcus faecalis / Q000201:enzymology / Q000235:genetics; D048168:Escherichia coli K12 / Q000235:genetics / Q000378:metabolism; D005227:Fatty Acids / Q000096:biosynthesis; D005230:Fatty Acids, Nonesterified / Q000096:biosynthesis*; D017353:Gene Deletion; D015870:Gene Expression; D005798:Genes, Bacterial; D005818:Genetic Engineering; D005990:Glycerol / Q000378:metabolism; D007218:Industrial Microbiology; D013294:Lactococcus lactis / Q000201:enzymology* / Q000235:genetics*; D053858:Metabolic Networks and Pathways; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013869:Thiolester Hydrolases / Q000235:genetics* / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D056804:Biofuels; D003062:Codon; D004269:DNA, Bacterial; D005227:Fatty Acids; D005230:Fatty Acids, Nonesterified; D011994:Recombinant Proteins; D013869:Thiolester Hydrolases; C018748:oleoyl-(acyl-carrier-protein) hydrolase; D005990:Glycerol
keywords: Bacterial acyl-ACP TE; Codon-optimization; Crude glycerol; Free fatty acid; L. lactis; Total fatty acid