title: Enhancing microbial production of biofuels by expanding microbial metabolic pathways.
abstract: Fatty acid, isoprenoid, and alcohol pathways have been successfully engineered to produce biofuels. By introducing three genes, atfA, adhE, and pdc, into Escherichia coli to expand fatty acid pathway, up to 1.28 g/L of fatty acid ethyl esters can be achieved. The isoprenoid pathway can be expanded to produce bisabolene with a high titer of 900 mg/L in Saccharomyces cerevisiae. Short- and long-chain alcohols can also be effectively biosynthesized by extending the carbon chain of ketoacids with an engineered "+1" alcohol pathway. Thus, it can be concluded that expanding microbial metabolic pathways has enormous potential for enhancing microbial production of biofuels for future industrial applications. However, some major challenges for microbial production of biofuels should be overcome to compete with traditional fossil fuels: lowering production costs, reducing the time required to construct genetic elements and to increase their predictability and reliability, and creating reusable parts with useful and predictable behavior. To address these challenges, several aspects should be further considered in future: mining and transformation of genetic elements related to metabolic pathways, assembling biofuel elements and coordinating their functions, enhancing the tolerance of host cells to biofuels, and creating modular subpathways that can be easily interconnected.
authors: College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang Province, People's Republic of China.
authors: Ping
authors: P
authors: Yu
authors: College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang Province, People's Republic of China.
authors: Xingge
authors: X
authors: Chen
authors: College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou, Zhejiang Province, People's Republic of China.
authors: Peng
authors: P
authors: Li
mesh_terms: D056804:Biofuels; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D060847:Metabolic Engineering / Q000379:methods*; D053858:Metabolic Networks and Pathways / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D013729:Terpenes / Q000378:metabolism
chemical_list: D056804:Biofuels; D005227:Fatty Acids; D013729:Terpenes
keywords: alcohol-derived pathway; biofuels; fatty acid-derived pathway; isoprenoid-derived pathway; microbial production