A novel MVA-mediated pathway for isoprene production in engineered E. coli

BMC Biotechnology

Research Article

Huizhou Liu¹  Mo Xian¹  Hui Liu¹  Jianming Yang²  Qingjuan Nie³ 

[1] CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, 266101, Qingdao, China;CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, 266101, Qingdao, China;Key Lab of Applied Mycology, College of Life Sciences, Qingdao Agricultural University, 266109, Qingdao, China;Foreign Languages School, Qingdao Agricultural University, 266109, Qingdao, China;

关键词: Isoprene;    MVA-mediated pathway;    OleT;    OhyA;    E. coli;   

DOI  :  10.1186/s12896-016-0236-2

 received in 2015-06-27, accepted in 2016-01-13,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundTo deal with the increasingly severe energy crisis and environmental consequences, biofuels and biochemicals generated from renewable resources could serve as a promising alternative for replacing petroleum as a source of fuel and chemicals, among which isoprene (2-methyl-1,3-butadiene) in particular is of great significance in that it is an important platform chemical, which has been used in industrial production of synthetic rubber for tires and coatings or aviation fuel.ResultsWe firstly introduced fatty acid decarboxylase (OleTJE) from Jeotgalicoccus species into E. coli to directly convert MVA(mevalonate) into 3-methy-3-buten-1-ol. And then to transform 3-methy-3-buten-1-ol to isoprene, oleate hydratase (OhyAEM) from Elizabethkingia meningoseptica was overexpressed in E. coli. A novel biosynthetic pathway of isoprene in E. coli was established by co-expressing the heterologous mvaE gene encoding acetyl-CoA acetyltransferase/HMG-CoA reductase and mvaS gene encoding HMG-CoA synthase from Enterococcus faecalis, fatty acid decarboxylase (OleTJE) and oleate hydratase (OhyAEM). Furthermore, to enhance isoprene production, a further optimization of expression level of OleTJE, OhyAEM was carried out by using different promoters and copy numbers of plasmids. Thereafter, the fermentation process was also optimized to improve the production of isoprene. The final engineered strain, YJM33, bearing the innovative biosynthetic pathway of isoprene, was found to produce isoprene up to 2.2 mg/L and 620 mg/L under flask and fed-batch fermentation conditions, respectively.ConclusionsIn this study, by using metabolic engineering techniques, the novel MVA-mediated biosynthetic pathway of isoprene was successfully assembled in E. coli BL21(DE3) with the heterologous MVA upper pathway, OleTJE from Jeotgalicoccus species and OhyAEM from Elizabethkingia meningoseptica. Compared with traditional MVA pathway, the novel pathway is shortened by 3 steps. In addition, this is the first report on the reaction of converting MVA into 3-methy-3-buten-1-ol by fatty acid decarboxylase (OleTJE) from Jeotgalicoccus species. In brief, this study provided an alternative method for isoprene biosynthesis, which is largely different from the well-developed MEP pathway or MVA pathway.

【 授权许可】

CC BY   
© Yang et al. 2016