title: De novo biosynthesis of biodiesel by Escherichia coli in optimized fed-batch cultivation.
abstract: Biodiesel is a renewable alternative to petroleum diesel fuel that can contribute to carbon dioxide emission reduction and energy supply. Biodiesel is composed of fatty acid alkyl esters, including fatty acid methyl esters (FAMEs) and fatty acid ethyl esters (FAEEs), and is currently produced through the transesterification reaction of methanol (or ethanol) and triacylglycerols (TAGs). TAGs are mainly obtained from oilseed plants and microalgae. A sustainable supply of TAGs is a major bottleneck for current biodiesel production. Here we report the de novo biosynthesis of FAEEs from glucose, which can be derived from lignocellulosic biomass, in genetically engineered Escherichia coli by introduction of the ethanol-producing pathway from Zymomonas mobilis, genetic manipulation to increase the pool of fatty acyl-CoA, and heterologous expression of acyl-coenzyme A: diacylglycerol acyltransferase from Acinetobacter baylyi. An optimized fed-batch microbial fermentation of the modified E. coli strain yielded a titer of 922 mg L(-1) FAEEs that consisted primarily of ethyl palmitate, -oleate, -myristate and -palmitoleate.
authors.affiliation: Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China.
authors.forename: Yangkai
authors.initials: Y
authors.lastname: Duan
authors.forename: Zhi
authors.initials: Z
authors.lastname: Zhu
authors.forename: Ke
authors.initials: K
authors.lastname: Cai
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Tan
authors.forename: Xuefeng
authors.initials: X
authors.lastname: Lu
mesh_terms: D000150:Acinetobacter / Q000235:genetics; D056804:Biofuels; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D004951:Esterification; D004952:Esters / Q000737:chemistry / Q000378:metabolism; D000431:Ethanol / Q000378:metabolism; D005227:Fatty Acids / Q000737:chemistry / Q000378:metabolism; D005285:Fermentation; D008738:Methyl Ethers / Q000737:chemistry*; D014280:Triglycerides / Q000378:metabolism; D017355:Zymomonas / Q000235:genetics
chemical_list: D056804:Biofuels; D004952:Esters; D005227:Fatty Acids; D008738:Methyl Ethers; D014280:Triglycerides; D000431:Ethanol