title: High production of fatty alcohols in Escherichia coli with fatty acid starvation.
abstract: BACKGROUND
  Microbial biofuel synthesis attracting increasing attention. Great advances have been made in producing fatty alcohols from fatty acyl-CoAs and fatty acids in Escherichia coli. However, the low titers and limited knowledge regarding the basic characteristics of fatty alcohols, such as location and toxicity, have hampered large-scale industrialization. Further research is still needed.
  
  
  RESULTS
  In this study, we designed a novel and efficient strategy to enhance fatty alcohol production by inducing fatty acid starvation. We report the first use of deletions of acyl-ACP thioesterases to enhance fatty alcohol production. Transcriptional analysis was conducted to investigate the mechanism of the designed strategy. Then, fatty alcohol production was further enhanced by deletion of genes from competing pathways. Fatty alcohols were shown to be extracellular products with low toxicity. The final strain, E. coli MGL2, produced fatty alcohols at the remarkable level of 6.33 g/L under fed-batch fermentation, representing the highest reported titer of fatty alcohols produced by microorganisms.
  
  
  CONCLUSIONS
  Deletions of genes responsible for synthesis of fatty acids and competing products are promising strategies for fatty alcohol production. Our investigation of the location and toxicity of fatty alcohols suggest bright future for fatty alcohol production in E. coli.
authors.affiliation: Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 XiQiDao, Tianjin Airport Economic Area, Tianjin, 300308, China.
authors.forename: Yilan
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, No. 16, Nanxiaojie, Dongzhimennei, Beijing, 100700, China.
authors.forename: Sha
authors.initials: S
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China.
authors.forename: Jinjin
authors.initials: J
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China.
authors.forename: Jiemin
authors.initials: J
authors.lastname: Zhou
authors.affiliation: Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 XiQiDao, Tianjin Airport Economic Area, Tianjin, 300308, China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China.
authors.forename: Maohua
authors.initials: M
authors.lastname: Yang
authors.affiliation: Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 XiQiDao, Tianjin Airport Economic Area, Tianjin, 300308, China.
authors.forename: Xianni
authors.initials: X
authors.lastname: Qi
authors.affiliation: State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, China. jmxing@ipe.ac.cn.
authors.forename: Jianmin
authors.initials: J
authors.lastname: Xing
authors.affiliation: Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 XiQiDao, Tianjin Airport Economic Area, Tianjin, 300308, China. wang_qh@tib.cas.cn.
authors.forename: Qinhong
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 XiQiDao, Tianjin Airport Economic Area, Tianjin, 300308, China.
authors.forename: Yanhe
authors.initials: Y
authors.lastname: Ma
mesh_terms: D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D005233:Fatty Alcohols / Q000378:metabolism*; D005285:Fermentation; D060847:Metabolic Engineering
chemical_list: D005227:Fatty Acids; D005233:Fatty Alcohols
keywords: Acyl-ACP thioesterases; Escherichia coli; Fatty acid starvation; Fatty alcohols