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Escherichia coli as a host for metabolic engineering. Metab Eng 2018; 50:16-46. [DOI: 10.1016/j.ymben.2018.04.008] [Citation(s) in RCA: 181] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Revised: 04/11/2018] [Accepted: 04/12/2018] [Indexed: 12/21/2022]
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Vavitsas K, Fabris M, Vickers CE. Terpenoid Metabolic Engineering in Photosynthetic Microorganisms. Genes (Basel) 2018; 9:E520. [PMID: 30360565 PMCID: PMC6266707 DOI: 10.3390/genes9110520] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 10/17/2018] [Accepted: 10/17/2018] [Indexed: 12/13/2022] Open
Abstract
Terpenoids are a group of natural products that have a variety of roles, both essential and non-essential, in metabolism and in biotic and abiotic interactions, as well as commercial applications such as pharmaceuticals, food additives, and chemical feedstocks. Economic viability for commercial applications is commonly not achievable by using natural source organisms or chemical synthesis. Engineered bio-production in suitable heterologous hosts is often required to achieve commercial viability. However, our poor understanding of regulatory mechanisms and other biochemical processes makes obtaining efficient conversion yields from feedstocks challenging. Moreover, production from carbon dioxide via photosynthesis would significantly increase the environmental and potentially the economic credentials of these processes by disintermediating biomass feedstocks. In this paper, we briefly review terpenoid metabolism, outline some recent advances in terpenoid metabolic engineering, and discuss why photosynthetic unicellular organisms-such as algae and cyanobacteria-might be preferred production platforms for the expression of some of the more challenging terpenoid pathways.
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Affiliation(s)
- Konstantinos Vavitsas
- Australian Institute of Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD 4072, Australia.
- CSIRO Synthetic Biology Future Science Platform, GPO Box 2583, Brisbane, QLD 4001, Australia.
| | - Michele Fabris
- Climate Change Cluster, University of Technology Sydney, 15 Broadway, Ultimo, NSW 2007, Australia.
- CSIRO Synthetic Biology Future Science Platform, GPO Box 2583, Brisbane, QLD 4001, Australia.
| | - Claudia E Vickers
- Australian Institute of Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD 4072, Australia.
- CSIRO Synthetic Biology Future Science Platform, GPO Box 2583, Brisbane, QLD 4001, Australia.
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Kim SK, Kim SH, Subhadra B, Woo SG, Rha E, Kim SW, Kim H, Lee DH, Lee SG. A Genetically Encoded Biosensor for Monitoring Isoprene Production in Engineered Escherichia coli. ACS Synth Biol 2018; 7:2379-2390. [PMID: 30261142 DOI: 10.1021/acssynbio.8b00164] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Isoprene is a valuable precursor for synthetic rubber and a signature product of terpenoid pathways. Here, we developed an isoprene biosensor by employing a TbuT transcriptional regulator of Ralstonia pickettii to express a fluorescent reporter gene in response to intracellular isoprene in engineered Escherichia coli. The TbuT regulator recognizes isoprene as its less-preferred effector molecule; thus, we amplified the reporter gene expression using a T7 RNA polymerase-mediated transcriptional cascade and iteratively tuned the promoter transcribing tbuT to improve the sensitivity for detecting isoprene. When the engineered E. coli cells expressed heterologous genes for isoprene biosynthesis, the intracellular isoprene was expelled and the tbuT transcription factor was subsequently activated, leading to gfp expression. The chromosomal isoprene biosensor showed a linear correlation between GFP fluorescence and intracellular isoprene concentration. Using this chromosomal isoprene biosensor, we successfully identified the highest isoprene producer among four different E. coli strains producing different amounts of isoprene. The isoprene biosensor presented here can enable high-throughput screening of isoprene synthases and metabolic pathways for efficient and sustainable production of bioisoprene in engineered microbes.
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Affiliation(s)
- Seong Keun Kim
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
| | - Seo Hyun Kim
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
| | - Bindu Subhadra
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
| | - Seung-Gyun Woo
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon 34113, Republic of Korea
| | - Eugene Rha
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
| | - Seon-Won Kim
- Division of Applied Life Science (BK21 Plus), PMBBRC, Institute of Agriculture and Life Sciences, Gyeongsang National University, Jinju 52828, Republic of Korea
| | - Haseong Kim
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon 34113, Republic of Korea
| | - Dae-Hee Lee
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon 34113, Republic of Korea
| | - Seung-Goo Lee
- Synthetic Biology and Bioengineering Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology (UST), Daejeon 34113, Republic of Korea
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Yao Z, Zhou P, Su B, Su S, Ye L, Yu H. Enhanced Isoprene Production by Reconstruction of Metabolic Balance between Strengthened Precursor Supply and Improved Isoprene Synthase in Saccharomyces cerevisiae. ACS Synth Biol 2018; 7:2308-2316. [PMID: 30145882 DOI: 10.1021/acssynbio.8b00289] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Isoprene, as a versatile bulk chemical, has wide industrial applications. Here, we attempted to improve isoprene biosynthesis in Saccharomyces cerevisiae by simultaneous strengthening of precursor supply and conversion via a combination of pathway compartmentation and protein engineering. At first, a superior isoprene synthase mutant ISPSLN was created by saturation mutagenesis, leading to almost 4-fold improvement in isoprene production. Subsequent introduction of ISPSLN to strains with strengthened precursor supply in either cytoplasm or mitochondria implied an imperfect match between the synthesis and conversion of the isopentenyl pyrophosphate (IPP)/dimethylallyl diphosphate (DMAPP) pool. To reconstruct metabolic balance between the upstream and downstream flux, additional copies of diphosphomevalonate decarboxylase gene ( MVD1) and isopentenyl-diphosphate delta-isomerase gene ( IDI1) were introduced into the cytoplasmic and mitochondrial engineered strains. Finally, the diploid strain created by mating the above haploid strains produced 11.9 g/L of isoprene, the highest ever reported in eukaryotic cells.
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Affiliation(s)
- Zhen Yao
- Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, PR China
| | - Pingping Zhou
- Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, PR China
| | - Bingmei Su
- Fujian Key Laboratory of Marine Enzyme Engineering, College of Biological Science and Engineering, Fuzhou University, Fuzhou 350116, PR China
| | - Sisi Su
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, PR China
| | - Lidan Ye
- Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, PR China
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Zhejiang University, Hangzhou 310027, PR China
| | - Hongwei Yu
- Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, PR China
- Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Zhejiang University, Hangzhou 310027, PR China
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Biochemical characterization of isoprene synthase from Ipomoea batatas. J Biosci Bioeng 2018; 127:138-144. [PMID: 30190176 DOI: 10.1016/j.jbiosc.2018.07.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Revised: 07/23/2018] [Accepted: 07/24/2018] [Indexed: 10/28/2022]
Abstract
The bio-production process of isoprene, an essential chemical used in industry, is strongly limited by isoprene synthase. In our previous work, relatively high isoprene production was observed with isoprene synthase from Ipomoea batatas (IspSib). In this work the biochemical properties of IspSib were analyzed and compared with those of isoprene synthase from Populus alba (IspSpa) and other species. Firstly, IspSib and IspSpa were expressed, purified, and identified by SDS-PAGE and western blot analysis. Secondly, pH and temperature dependence of IspSib were performed and an optimum pH of 8.6 and an optimum temperature of 42 °C were resulted. Mg2+ with optimum concentration of 56 mM was proved to be needed for enzyme activation. In addition, in vivo and in vitro study of the thermostabilities of IspSib and IspSpa were performed. The enzyme activity of IspSib and IspSpa dropped very rapidly after incubation at 30 °C; almost 80% enzyme activity of IspSib was lost after 20 min of incubation. Moreover, the Michaelis-Menten constant was measured. IspSib showed a lower Km, 0.2 mM, and a higher kcat, 0.37 s-1, as compared with IspSpa. The high catalytic efficiency, which was reflected by the high kcat/Km ratio, indicates that IspSib is a good candidate for the bio-isoprene production, while its thermal instability remains as a challenge. Enzyme engineering efforts, such as direction evolution or semi-rational evolution, are planned for further research.
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Li M, Nian R, Xian M, Zhang H. Metabolic engineering for the production of isoprene and isopentenol by Escherichia coli. Appl Microbiol Biotechnol 2018; 102:7725-7738. [PMID: 30006784 PMCID: PMC6132537 DOI: 10.1007/s00253-018-9200-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Revised: 06/23/2018] [Accepted: 06/25/2018] [Indexed: 12/12/2022]
Abstract
The biotechnological production of isoprene and isopentenol has recently been studied. Isoprene, which is currently made mainly from petroleum, is an important platform chemical for synthesizing pesticides, medicines, oil additives, fragrances, and more and is especially important in the rubber production industry. Isopentenols, which have better combustion properties than well-known biofuels (ethanol), have recently received more attention. Supplies of petroleum, the conventional source of isoprene and isopentenols, are unsustainable, and chemical synthesis processes could cause serious environmental problems. As an alternative, the biosynthesis of isoprene and isopentenols in cell factories is more sustainable and environmentally friendly. With a number of advantages over other microorganisms, Escherichia coli is considered to be a powerful workhorse organism for producing these compounds. This review will highlight the recent advances in metabolic engineering for isoprene and isopentenol production, especially using E. coli cell factories.
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Affiliation(s)
- Meijie Li
- Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 135 Songling Road, Qingdao, 266101, People's Republic of China.,University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Rui Nian
- Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 135 Songling Road, Qingdao, 266101, People's Republic of China
| | - Mo Xian
- Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 135 Songling Road, Qingdao, 266101, People's Republic of China.
| | - Haibo Zhang
- Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 135 Songling Road, Qingdao, 266101, People's Republic of China.
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57
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Yeom SJ, Kim M, Kim SK, Lee DH, Kwon KK, Lee H, Kim H, Kim DM, Lee SG. Molecular and biochemical characterization of a novel isoprene synthase from Metrosideros polymorpha. BMC PLANT BIOLOGY 2018; 18:118. [PMID: 29902970 PMCID: PMC6003189 DOI: 10.1186/s12870-018-1315-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 05/21/2018] [Indexed: 05/11/2023]
Abstract
BACKGROUND Isoprene is a five-carbon chemical that is an important starting material for the synthesis of rubber, elastomers, and medicines. Although many plants produce huge amounts of isoprene, it is very difficult to obtain isoprene directly from plants because of its high volatility and increasing environmental regulations. Over the last decade, microorganisms have emerged as a promising alternative host for efficient and sustainable bioisoprene production. Isoprene synthase (IspS) has received much attention for the conversion of isoprene from dimethylallyl diphosphate (DMAPP). Herein, we isolated a highly expressible novel IspS gene from Metrosideros polymorpha (MpIspS), which was cloned and expressed in Escherichia coli, using a plant cDNA library and characterized its molecular and biochemical properties. RESULTS The signal sequence deleted MpIspS was cloned and expressed in E. coli as a 65-kDa monomer. The maximal activity of the purified MpIspS was observed at pH 6.0 and 55 °C in the presence of 5 mM Mn2+. The Km, kcat, and kcat/Km for DMAPP as a substrate were 8.11 mM, 21 min- 1, and 2.59 mM- 1 min- 1, respectively. MpIspS was expressed along with the exogenous mevalonate pathway to produce isoprene in E. coli. The engineered cells produced isoprene concentrations of up to 23.3 mg/L using glycerol as the main carbon source. CONCLUSION MpIspS was expressed in large amounts in E. coli, which led to increased enzymatic activity and resulted in isoprene production in vivo. These results demonstrate a new IspS enzyme that is useful as a key biocatalyst for bioisoprene production in engineered microbes.
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Affiliation(s)
- Soo-Jin Yeom
- Synthetic Biology and Bioengineering Research Center, KRIBB, Daejeon, 34141 Republic of Korea
| | - Moonjung Kim
- Synthetic Biology and Bioengineering Research Center, KRIBB, Daejeon, 34141 Republic of Korea
- Department of Chemical Engineering and Applied Chemistry, Chungnam National University, Daejeon, 34113 Republic of Korea
| | - Seong Keun Kim
- Synthetic Biology and Bioengineering Research Center, KRIBB, Daejeon, 34141 Republic of Korea
| | - Dae-Hee Lee
- Synthetic Biology and Bioengineering Research Center, KRIBB, Daejeon, 34141 Republic of Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology, Daejeon, 34113 Republic of Korea
| | - Kil Koang Kwon
- Synthetic Biology and Bioengineering Research Center, KRIBB, Daejeon, 34141 Republic of Korea
| | - Hyewon Lee
- Synthetic Biology and Bioengineering Research Center, KRIBB, Daejeon, 34141 Republic of Korea
| | - Haseong Kim
- Synthetic Biology and Bioengineering Research Center, KRIBB, Daejeon, 34141 Republic of Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology, Daejeon, 34113 Republic of Korea
| | - Dong-Myung Kim
- Department of Chemical Engineering and Applied Chemistry, Chungnam National University, Daejeon, 34113 Republic of Korea
| | - Seung-Goo Lee
- Synthetic Biology and Bioengineering Research Center, KRIBB, Daejeon, 34141 Republic of Korea
- Department of Biosystems and Bioengineering, KRIBB School of Biotechnology, University of Science and Technology, Daejeon, 34113 Republic of Korea
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Chen H, Li M, Liu C, Zhang H, Xian M, Liu H. Enhancement of the catalytic activity of Isopentenyl diphosphate isomerase (IDI) from Saccharomyces cerevisiae through random and site-directed mutagenesis. Microb Cell Fact 2018; 17:65. [PMID: 29712558 PMCID: PMC5925831 DOI: 10.1186/s12934-018-0913-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 04/24/2018] [Indexed: 11/21/2022] Open
Abstract
Background Lycopene is a terpenoid pigment that has diverse applications in the food and medicine industries. A prospective approach for lycopene production is by metabolic engineering in microbial hosts, such as Escherichia coli. Isopentenyl diphosphate isomerase (IDI, E.C. 5.3.3.2) is one of the rate-limiting enzymes in the lycopene biosynthetic pathway and one major target during metabolic engineering. The properties of IDIs differ depending on the sources, but under physiological conditions, IDIs are limited by low enzyme activity, short half-life and weak substrate affinity. Therefore, it is important to prepare an excellent IDI by protein engineering. Results Directed evolution strategy (error-prone PCR) was utilized to optimize the activity of Saccharomyces cerevisiae IDI. Using three rounds of error-prone PCR; screening the development of a lycopene-dependent color reaction; and combinatorial site-specific saturation mutagenesis, three activity-enhancing mutations were identified: L141H, Y195F, and W256C. L141H, located near the active pocket inside the tertiary structure of IDI, formed a hydrogen bond with nearby β-phosphates of isopentenylpyrophosphate (IPP). Phe-195 and Cys-256 were nonpolar amino acids and located near the hydrophobic group of IPP, enlarging the hydrophobic scope, and the active pocket indirectly. Purified IDI was characterized and the result showed that the Km of mutant IDI decreased by 10% compared with Km of the parent IDI, and Kcat was 28% fold improved compared to that of the original IDI. Results of a fermentation experiment revealed that mutant IDI had a 1.8-fold increased lycopene production and a 2.1-fold increased yield capacity compared to wild-type IDI. Conclusion We prepared an engineered variant of IDI with improved catalytic activity by combining random and site directed mutagenesis. The best mutants produced by this approach enhanced catalytic activity while also displaying improved stability in pH, enhanced thermostability and longer half-life. Importantly, the mutant IDI could play an important role in fed-batch fermentation, being an effective and attractive biocatalyst for the production of biochemicals. Electronic supplementary material The online version of this article (10.1186/s12934-018-0913-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hailin Chen
- CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101, People's Republic of China.,Sino-Danish College, University of Chinese Academy of Sciences, No. 19(A) Yuquan Road, Beijing, 100049, People's Republic of China
| | - Meijie Li
- CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101, People's Republic of China
| | - Changqing Liu
- CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101, People's Republic of China
| | - Haibo Zhang
- CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101, People's Republic of China.
| | - Mo Xian
- CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101, People's Republic of China.
| | - Huizhou Liu
- CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Qingdao, 266101, People's Republic of China
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Liu C, Men X, Chen H, Li M, Ding Z, Chen G, Wang F, Liu H, Wang Q, Zhu Y, Zhang H, Xian M. A systematic optimization of styrene biosynthesis in Escherichia coli BL21(DE3). BIOTECHNOLOGY FOR BIOFUELS 2018; 11:14. [PMID: 29416559 PMCID: PMC5784704 DOI: 10.1186/s13068-018-1017-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Accepted: 01/10/2018] [Indexed: 05/28/2023]
Abstract
BACKGROUND Styrene is a versatile commodity petrochemical used as a monomer building-block for the synthesis of many useful polymers. Although achievements have been made on styrene biosynthesis in microorganisms, several bottleneck problems limit factors for further improvement in styrene production. RESULTS A two-step styrene biosynthesis pathway was developed and introduced into Escherichia coli BL21(DE3). Systematic optimization of styrene biosynthesis, such as enzyme screening, codon and plasmid optimization, metabolic flow balance, and in situ fermentation was performed. Candidate isoenzymes of the rate-limiting enzyme phenylalanine ammonia lyase (PAL) were screened from Arabidopsis thaliana (AtPAL2), Fagopyrum tataricum (FtPAL), Petroselinum crispum (PcPAL), and Artemisia annua (AaPAL). After codon optimization, AtPAL2 was found to be the most effective one, and the engineered strain was able to produce 55 mg/L styrene. Subsequently, plasmid optimization was performed, which improved styrene production to 103 mg/L. In addition, two upstream shikimate pathway genes, aroF and pheA, were overexpressed in the engineered strain, which resulted in styrene production of 210 mg/L. Subsequently, combined overexpression of tktA and ppsA increased styrene production to 275 mg/L. Finally, in situ product removal was used to ease the burden of end-product toxicity. By using isopropyl myristate as a solvent, styrene production reached a final titer of 350 mg/L after 48 h of shake-flask fermentation, representing a 636% improvement, which compared with that achieved in the original strain. CONCLUSIONS This present study achieved the highest titer of de novo production of styrene in E. coli at shake-flask fermentation level. These results obtained provided new insights for the development of microbial production of styrene in a sustainable and environment friendly manner.
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Affiliation(s)
- Changqing Liu
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Xiao Men
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Hailin Chen
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Meijie Li
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Zhaorui Ding
- School of Biological Science, Jining Medical University, Jining, 272067 People’s Republic of China
| | - Guoqiang Chen
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Fan Wang
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Haobao Liu
- Key Laboratory for Tobacco, Gene Resources’ Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101 People’s Republic of China
| | - Qian Wang
- Key Laboratory for Tobacco, Gene Resources’ Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao, 266101 People’s Republic of China
| | - Youshuang Zhu
- School of Biological Science, Jining Medical University, Jining, 272067 People’s Republic of China
| | - Haibo Zhang
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
| | - Mo Xian
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No.189 Songling Road, Laoshan District, Qingdao, 266101 China
- University of Chinese Academy of Sciences, Beijing, China
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Wilson J, Gering S, Pinard J, Lucas R, Briggs BR. Bio-production of gaseous alkenes: ethylene, isoprene, isobutene. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:234. [PMID: 30181774 PMCID: PMC6114056 DOI: 10.1186/s13068-018-1230-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 08/17/2018] [Indexed: 05/05/2023]
Abstract
To reduce emissions from petrochemical refinement, bio-production has been heralded as a way to create economically valuable compounds with fewer harmful effects. For example, gaseous alkenes are precursor molecules that can be polymerized into a variety of industrially significant compounds and have biological production pathways. Production levels, however, remain low, thus enhancing bio-production of gaseous petrochemicals for chemical precursors is critical. This review covers the metabolic pathways and production levels of the gaseous alkenes ethylene, isoprene, and isobutene. Techniques needed to drive production to higher levels are also discussed.
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Affiliation(s)
- James Wilson
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508 USA
| | - Sarah Gering
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508 USA
| | - Jessica Pinard
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508 USA
| | - Ryan Lucas
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508 USA
| | - Brandon R. Briggs
- Department of Biological Sciences, University of Alaska Anchorage, Anchorage, AK 99508 USA
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61
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Biosynthesis and production of sabinene: current state and perspectives. Appl Microbiol Biotechnol 2017; 102:1535-1544. [DOI: 10.1007/s00253-017-8695-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 12/03/2017] [Accepted: 12/04/2017] [Indexed: 01/10/2023]
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Chaves JE, Rueda-Romero P, Kirst H, Melis A. Engineering Isoprene Synthase Expression and Activity in Cyanobacteria. ACS Synth Biol 2017; 6:2281-2292. [PMID: 28858481 DOI: 10.1021/acssynbio.7b00214] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Efforts to heterologously produce quantities of isoprene hydrocarbons (C5H8) renewably from CO2 and H2O through the photosynthesis of cyanobacteria face barriers, including low levels of recombinant enzyme accumulation compounded by their slow innate catalytic activity. The present work sought to alleviate the "expression level" barrier upon placing the isoprene synthase (IspS) enzyme in different fusion configurations with the cpcB protein, the highly expressed β-subunit of phycocyanin. Different cpcB*IspS fusion constructs were made, distinguished by the absence or presence of linker amino acids between the two proteins. Composition of linker amino acids was variable with lengths of 7, 10, 16, and 65 amino acids designed to test for optimal activity of the IspS through spatial positioning between the cpcB and IspS. Results showed that fusion constructs with the highly expressed cpcB gene, as the leader sequence, improved transgene expression in the range of 61 to 275-fold over what was measured with the unfused IspS control. However, the specific activity of the IspS enzyme was attenuated in all fusion transformants, possibly because of allosteric effects exerted by the leader cpcB fusion protein. This inhibition varied depending on the nature of the linker amino acids between the cpcB and IspS proteins. In terms of isoprene production, the results further showed a trade-off between specific activity and transgenic enzyme accumulation. For example, the cpcB*L7*IspS strain showed only about 10% the isoprene synthase specific-activity of the unfused cpcB-IspS control, but it accumulated 254-fold more IspS enzyme. The latter more than countered the slower specific activity and made the cpcB*L7*IspS transformant the best isoprene producing strain in this work. Isoprene to biomass yield ratios improved from 0.2 mg g-1 in the unfused cpcB-IspS control to 5.4 mg g-1 in the cpcB*L7*IspS strain, a 27-fold improvement.
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Affiliation(s)
- Julie E. Chaves
- Plant and Microbial Biology, University of California, Berkeley, California 94720-3102, United States
| | - Paloma Rueda-Romero
- Plant and Microbial Biology, University of California, Berkeley, California 94720-3102, United States
| | - Henning Kirst
- Plant and Microbial Biology, University of California, Berkeley, California 94720-3102, United States
| | - Anastasios Melis
- Plant and Microbial Biology, University of California, Berkeley, California 94720-3102, United States
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A novel DMAPP-responding genetic circuit sensor for high-throughput screening and evolving isoprene synthase. Appl Microbiol Biotechnol 2017; 102:1381-1391. [PMID: 29243081 DOI: 10.1007/s00253-017-8676-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 11/19/2017] [Accepted: 11/24/2017] [Indexed: 12/14/2022]
Abstract
High-throughput screening is a popular tool for collating biological data which would otherwise require the use of excessive resources. In this study, an artificial genetic circuit sensor responding to dimethylallyl diphosphate (DMAPP) was constructed based on a modified L-arabinose operon for high-throughput screening and isoprene synthase (ispS) evolution in Escherichia coli (E. coli). As a first step, the DNA sequence of the L-arabinose ligand-binding domain (LBD) was replaced with an ispS gene to enable the AraC operon responding to DMAPP, which is the substrate of the IspS enzyme. Then, an enhanced GFP (eGFP) was also introduced as a reporter for pBAD promoter. The expression level of the reporter was monitored using either of the two tools: flow cytometer (FCM) and microplate reader. Sequentially, we observed that a high DMAPP concentration led to low eGFP fluorescence, and the overexpression of ispS gene, which consumes DMAPP, resulted in a high eGFP expression. These results demonstrated that the artificial genetic circuit sensor responded directly to the intracellular concentration of DMAPP, and the expression of IspS enzyme could be positively correlated to the expression level of eGFP. Finally, we identified two IspS mutants with different activities from an ispS gene library and further validated the screening method.
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64
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Liu H, Cheng T, Zou H, Zhang H, Xu X, Sun C, Aboulnaga E, Cheng Z, Zhao G, Xian M. High titer mevalonate fermentation and its feeding as a building block for isoprenoids (isoprene and sabinene) production in engineered Escherichia coli. Process Biochem 2017. [DOI: 10.1016/j.procbio.2017.07.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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65
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Wang C, Zada B, Wei G, Kim SW. Metabolic engineering and synthetic biology approaches driving isoprenoid production in Escherichia coli. BIORESOURCE TECHNOLOGY 2017; 241:430-438. [PMID: 28599221 DOI: 10.1016/j.biortech.2017.05.168] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 05/24/2017] [Accepted: 05/26/2017] [Indexed: 05/20/2023]
Abstract
Isoprenoids comprise the largest family of natural organic compounds with many useful applications in the pharmaceutical, nutraceutical, and industrial fields. Rapid developments in metabolic engineering and synthetic biology have facilitated the engineering of isoprenoid biosynthetic pathways in Escherichia coli to induce high levels of production of many different isoprenoids. In this review, the stem pathways for synthesizing isoprene units as well as the branch pathways deriving diverse isoprenoids from the isoprene units have been summarized. The review also highlights the metabolic engineering efforts made for the biosynthesis of hemiterpenoids, monoterpenoids, sesquiterpenoids, diterpenoids, carotenoids, retinoids, and coenzyme Q10 in E. coli. Perspectives and future directions for the synthesis of novel isoprenoids, decoration of isoprenoids using cytochrome P450 enzymes, and secretion or storage of isoprenoids in E. coli have also been included.
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Affiliation(s)
- Chonglong Wang
- School of Biology and Basic Medical Sciences, Soochow University, Suzhou, People's Republic of China
| | - Bakht Zada
- Division of Applied Life Science (BK21 Plus), PMBBRC, Institute of Agriculture and Life Sciences, Gyeongsang National University, Jinju, Republic of Korea
| | - Gongyuan Wei
- School of Biology and Basic Medical Sciences, Soochow University, Suzhou, People's Republic of China
| | - Seon-Won Kim
- Division of Applied Life Science (BK21 Plus), PMBBRC, Institute of Agriculture and Life Sciences, Gyeongsang National University, Jinju, Republic of Korea.
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66
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Kim JW, Yoon HC, Kwon SJ, Lee BY, Lee PC. Purification of biomevalonate from fermentation broth and conversion of biomevalonate into biomevalonolactone. J Biotechnol 2017; 259:46-49. [DOI: 10.1016/j.jbiotec.2017.08.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 08/03/2017] [Accepted: 08/15/2017] [Indexed: 10/19/2022]
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Wang S, Yang J. Isoprenoids Production from Lipid-Extracted Microalgal Biomass Residues Using Engineered E. coli. Molecules 2017; 22:molecules22060960. [PMID: 28598364 PMCID: PMC6152769 DOI: 10.3390/molecules22060960] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 06/01/2017] [Accepted: 06/07/2017] [Indexed: 11/16/2022] Open
Abstract
Microalgae are recognized as a third generation feedstock for biofuel production due to their rapid growth rates and lignin-free characteristics. In this study, a lipid extracted microalgal biomass residues was used as the raw material to produce isoprene, α-pinene and β-pinene with an engineered E. coli strain. We adopted an optimal sulfuric acid hydrolysis method (1:7 ratio of solid to acid solution, 32% (w/v) concentration of sulfuric acid solution at 90 °C for 90 min) to efficiently convert holocellulose into glucose efficiently (6.37 g/L). Futhermore, we explored a novel detoxification strategy (phosphoric acid/calcium hydroxide) to remove inhibitors and notably acetic acid, furfural and 5-hydroxymethylfurfural (5-HMF) were reduced by 5.32%, different number given later 99.19% and 98.22%, respectively. Finally, the fermentation concentrations of isoprene (223.23 mg/L), α-pinene (382.21 μg/L) and β-pinene (17.4 mg/L) were achieved using the detoxified hydrolysate as the carbon source, equivalent to approximately 86.02%, 90.16% and 88.32% of those produced by the engineered E. coli strain fermented on pure glucose, respectively.
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Affiliation(s)
- Sumeng Wang
- Key Lab of Applied Mycology, College of Life Sciences, Qingdao Agricultural University, Qingdao 266109, China.
| | - Jianming Yang
- Key Lab of Applied Mycology, College of Life Sciences, Qingdao Agricultural University, Qingdao 266109, China.
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68
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Xu X, Xie M, Zhao Q, Xian M, Liu H. Microbial production of mevalonate by recombinant Escherichia coli using acetic acid as a carbon source. Bioengineered 2017; 9:116-123. [PMID: 28574746 PMCID: PMC5972924 DOI: 10.1080/21655979.2017.1323592] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
We sought to produce mevalonate, an important organic acid, by recombinant Escherichia coli, using acetic acid, a less costly alternative feedstock, as a carbon source. In this study, the mevalonate biosynthesis pathway originating with acetate was constructed in recombinant E. coli, resulting in the production of 1.06 g L-1 mevalonate with a productivity of 0.03 g L-1 h-1 in a 5-L bioreactor. The mevalonate concentration and productivity were significantly enhanced with increased cell density during 2-stage aerobic fermentation, reaching 7.85 g L-1 and 0.13 g L-1 h-1, respectively. Fed-batch fermentation was further optimized under anaerobic and microaerobic conditions, and mevalonate concentrations reached 3.05 g L-1 and 4.97 g L-1, respectively, indicating that the oxygen supply exerts a large impact on mevalonate production from acetate. This study describes a method with high potential to produce mevalonate with the engineered E. coli strain XU143 using the less costly alternative feedstock acetate as a carbon source.
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Affiliation(s)
- Xin Xu
- a CAS Key Laboratory of Biobased Materials , Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences , Qingdao , China.,b University of Chinese Academy of Sciences , Beijing , China
| | - Meng Xie
- a CAS Key Laboratory of Biobased Materials , Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences , Qingdao , China
| | - Qian Zhao
- c College of Environment and Safety Engineering, Qingdao University of Science and Technology , Qingdao , China
| | - Mo Xian
- a CAS Key Laboratory of Biobased Materials , Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences , Qingdao , China
| | - Huizhou Liu
- a CAS Key Laboratory of Biobased Materials , Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences , Qingdao , China
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69
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Lee SQE, Tan TS, Kawamukai M, Chen ES. Cellular factories for coenzyme Q 10 production. Microb Cell Fact 2017; 16:39. [PMID: 28253886 PMCID: PMC5335738 DOI: 10.1186/s12934-017-0646-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 02/10/2017] [Indexed: 04/20/2023] Open
Abstract
Coenzyme Q10 (CoQ10), a benzoquinone present in most organisms, plays an important role in the electron-transport chain, and its deficiency is associated with various neuropathies and muscular disorders. CoQ10 is the only lipid-soluble antioxidant found in humans, and for this, it is gaining popularity in the cosmetic and healthcare industries. To meet the growing demand for CoQ10, there has been considerable interest in ways to enhance its production, the most effective of which remains microbial fermentation. Previous attempts to increase CoQ10 production to an industrial scale have thus far conformed to the strategies used in typical metabolic engineering endeavors. However, the emergence of new tools in the expanding field of synthetic biology has provided a suite of possibilities that extend beyond the traditional modes of metabolic engineering. In this review, we cover the various strategies currently undertaken to upscale CoQ10 production, and discuss some of the potential novel areas for future research.
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Affiliation(s)
- Sean Qiu En Lee
- Department of Biochemistry, National University of Singapore, Singapore, Singapore
| | - Tsu Soo Tan
- School of Chemical & Life Sciences, Nanyang Polytechnic, Singapore, Singapore
| | - Makoto Kawamukai
- Faculty of Life and Environmental Science, Shimane University, Matsue, 690-8504, Japan
| | - Ee Sin Chen
- Department of Biochemistry, National University of Singapore, Singapore, Singapore. .,National University Health System (NUHS), Singapore, Singapore. .,NUS Synthetic Biology for Clinical and Technological Innovation (SynCTI), Life Sciences Institute, National University of Singapore, Singapore, Singapore. .,NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore, Singapore.
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70
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Cheng T, Liu H, Zou H, Chen N, Shi M, Xie C, Zhao G, Xian M. Enzymatic process optimization for the in vitro production of isoprene from mevalonate. Microb Cell Fact 2017; 16:8. [PMID: 28068985 PMCID: PMC5223365 DOI: 10.1186/s12934-016-0622-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 12/27/2016] [Indexed: 11/26/2022] Open
Abstract
Background As an important bulk chemical for synthetic rubber, isoprene can be biosynthesized by robust microbes. But rational engineering and optimization are often demanded to make the in vivo process feasible due to the complexities of cellular metabolism. Alternative synthetic biochemistry strategies are in fast development to produce isoprene or isoprenoids in vitro. Results This study set up an in vitro enzyme synthetic chemistry process using 5 enzymes in the lower mevalonate pathway to produce isoprene from mevalonate. We found the level and ratio of individual enzymes would significantly affect the efficiency of the whole system. The optimized process using 10 balanced enzyme unites (5.0 µM of MVK, PMK, MVD; 10.0 µM of IDI, 80.0 µM of ISPS) could produce 6323.5 µmol/L/h (430 mg/L/h) isoprene in a 2 ml in vitro system. In a scale up process (50 ml) only using 1 balanced enzyme unit (0.5 µM of MVK, PMK, MVD; 1.0 µM of IDI, 8.0 µM of ISPS), the system could produce 302 mg/L isoprene in 40 h, which showed higher production rate and longer reaction phase with comparison of the in vivo control. Conclusions By optimizing the enzyme levels of lower MVA pathway, synthetic biochemistry methods could be set up for the enzymatic production of isoprene or isoprenoids from mevalonate.
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Affiliation(s)
- Tao Cheng
- CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Laoshan District, Qingdao, 266101, China.,State Key Laboratory Base of Eco-Chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
| | - Hui Liu
- CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Laoshan District, Qingdao, 266101, China
| | - Huibin Zou
- CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Laoshan District, Qingdao, 266101, China. .,College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China.
| | - Ningning Chen
- College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
| | - Mengxun Shi
- College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
| | - Congxia Xie
- State Key Laboratory Base of Eco-Chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao, 266042, China
| | - Guang Zhao
- CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Laoshan District, Qingdao, 266101, China.
| | - Mo Xian
- CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No. 189 Songling Road, Laoshan District, Qingdao, 266101, China.
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71
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Wang S, Wang Z, Wang Y, Nie Q, Yi X, Ge W, Yang J, Xian M. Production of isoprene, one of the high-density fuel precursors, from peanut hull using the high-efficient lignin-removal pretreatment method. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:297. [PMID: 29234464 PMCID: PMC5721603 DOI: 10.1186/s13068-017-0988-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 12/02/2017] [Indexed: 05/12/2023]
Abstract
BACKGROUND Isoprene as the feedstock can be used to produce renewable energy fuels, providing an alternative to replace the rapidly depleting fossil fuels. However, traditional method for isoprene production could not meet the demands for low-energy consumption and environment-friendliness. Moreover, most of the previous studies focused on biofuel production out of lignocellulosic materials such as wood, rice straw, corn cob, while few studies concentrated on biofuel production using peanut hull (PH). As is known, China is the largest peanut producer in the globe with an extremely considerable amount of PH to be produced each year. Therefore, a novel, renewable, and environment-friendly pretreatment strategy to increase the enzymatic hydrolysis efficiency of cellulose and reduce the inhibitors generation was developed to convert PH into isoprene. RESULTS The optimal pretreatment conditions were 100 °C, 60 min, 10% (w/v) solid loading with a 2:8 volume ratio of phosphoric acid and of hydrogen peroxide. In comparison with the raw PH, the hemicellulose and lignin were reduced to 85.0 and 98.0%, respectively. The cellulose-glucose conversion of pretreated PH reached up to 95.0% in contrast to that of the raw PH (19.1%). Only three kinds of inhibitors including formic acid, levulinic acid, and a little furfural were formed during the pretreatment process, whose concentrations were too low to inhibit the isoprene yield for Escherichia coli fermentation. Moreover, compared with the isoprene yield of pure glucose fermentation (298 ± 9 mg/L), 249 ± 6.7 and 294 ± 8.3 mg/L of isoprene were produced using the pretreated PH as the carbon source by the engineered strain via separate hydrolysis and fermentation and simultaneous saccharification and fermentation (SSF) methods, respectively. The isoprene production via SSF had a 9.8% glucose-isoprene conversion which was equivalent to 98.8% of isoprene production via the pure glucose fermentation. CONCLUSIONS The optimized phosphoric acid/hydrogen peroxide combination pretreatment approach was proved effective to remove lignin and hemicellulose from lignocellulosic materials. Meanwhile, the pretreated PH could be converted into isoprene efficiently in the engineered Escherichia coli. It is concluded that this novel strategy of isoprene production using lignocellulosic materials pretreated by phosphoric acid/hydrogen peroxide is a promising alternative to isoprene production using traditional way which can fully utilize non-renewable fossil sources.
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Affiliation(s)
- Sumeng Wang
- Shandong Key Lab of Applied Mycology, College of Life Science, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang District, Qingdao, 266109 China
| | - Zhaobao Wang
- Shandong Key Lab of Applied Mycology, College of Life Science, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang District, Qingdao, 266109 China
| | - Yongchao Wang
- Shandong Key Lab of Applied Mycology, College of Life Science, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang District, Qingdao, 266109 China
| | - Qingjuan Nie
- Foreign Languages School, Qingdao Agricultural University, Qingdao, 266109 China
| | - Xiaohua Yi
- Shandong Key Lab of Applied Mycology, College of Life Science, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang District, Qingdao, 266109 China
| | - Wei Ge
- Shandong Key Lab of Applied Mycology, College of Life Science, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang District, Qingdao, 266109 China
| | - Jianming Yang
- Shandong Key Lab of Applied Mycology, College of Life Science, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang District, Qingdao, 266109 China
| | - Mo Xian
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China
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Kim JH, Wang C, Jang HJ, Cha MS, Park JE, Jo SY, Choi ES, Kim SW. Isoprene production by Escherichia coli through the exogenous mevalonate pathway with reduced formation of fermentation byproducts. Microb Cell Fact 2016; 15:214. [PMID: 28010736 PMCID: PMC5180398 DOI: 10.1186/s12934-016-0612-6] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 12/04/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Isoprene, a volatile C5 hydrocarbon, is an important platform chemical used in the manufacturing of synthetic rubber for tires and various other applications, such as elastomers and adhesives. RESULTS In this study, Escherichia coli MG1655 harboring Populus trichocarpa isoprene synthase (PtispS) and the exogenous mevalonate (MVA) pathway produced 80 mg/L isoprene. Codon optimization and optimal expression of the ispS gene via adjustment of the RBS strength and inducer concentration increased isoprene production to 199 and 337 mg/L, respectively. To augment expression of MVA pathway genes, the MVA pathway was cloned on a high-copy plasmid (pBR322 origin) with a strong promoter (Ptrc), which resulted in an additional increase in isoprene production up to 956 mg/L. To reduce the formation of byproducts derived from acetyl-CoA (an initial substrate of the MVA pathway), nine relevant genes were deleted to generate the E. coli AceCo strain (E. coli MG1655 ΔackA-pta, poxB, ldhA, dld, adhE, pps, and atoDA). The AceCo strain harboring the ispS gene and MVA pathway showed enhanced isoprene production of 1832 mg/L in flask culture with reduced accumulation of byproducts. CONCLUSIONS We achieved a 23-fold increase in isoprene production by codon optimization of PtispS, augmentation of the MVA pathway, and deletion of genes involved in byproduct formation.
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Affiliation(s)
- Jung-Hun Kim
- Division of Applied Life Science (BK21 Plus), PMBBRC, Institute of Agricultural and Life Science, Gyeongsang National University, Jinju, 52828, South Korea.,Research Center for Industrial Chemical Biotechnology, KRICT, Ulsan, 44468, South Korea
| | - Chonglong Wang
- Division of Applied Life Science (BK21 Plus), PMBBRC, Institute of Agricultural and Life Science, Gyeongsang National University, Jinju, 52828, South Korea
| | - Hui-Jung Jang
- Division of Applied Life Science (BK21 Plus), PMBBRC, Institute of Agricultural and Life Science, Gyeongsang National University, Jinju, 52828, South Korea.,Life Science Research Institute, Daewoong Pharmaceutical Corporation, Yongin, South Korea
| | - Myeong-Seok Cha
- Division of Applied Life Science (BK21 Plus), PMBBRC, Institute of Agricultural and Life Science, Gyeongsang National University, Jinju, 52828, South Korea
| | - Ju-Eon Park
- Division of Applied Life Science (BK21 Plus), PMBBRC, Institute of Agricultural and Life Science, Gyeongsang National University, Jinju, 52828, South Korea
| | - Seon-Yeong Jo
- Division of Applied Life Science (BK21 Plus), PMBBRC, Institute of Agricultural and Life Science, Gyeongsang National University, Jinju, 52828, South Korea
| | - Eui-Sung Choi
- Industrial Biotechnology Research Center, KRIBB, Daejeon, 305-806, South Korea.
| | - Seon-Won Kim
- Division of Applied Life Science (BK21 Plus), PMBBRC, Institute of Agricultural and Life Science, Gyeongsang National University, Jinju, 52828, South Korea.
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Huibin Z, Liu H, Aboulnaga E, Liu H, Cheng T, Xian M. Microbial Production of Isoprene: Opportunities and Challenges. Ind Biotechnol (New Rochelle N Y) 2016. [DOI: 10.1002/9783527807833.ch16] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Zou Huibin
- Qingdao Institute of Bioenergy and Bioprocess Technology; Chinese Academy of Sciences, CAS Key Laboratory of Bio-based Materials; No. 189 Songling Road Qingdao 266101 China
- Qingdao University of Science and Technology; College of Chemical Engineering; No. 53 Zhengzhou Road Qingdao 266042 China
| | - Hui Liu
- Qingdao Institute of Bioenergy and Bioprocess Technology; Chinese Academy of Sciences, CAS Key Laboratory of Bio-based Materials; No. 189 Songling Road Qingdao 266101 China
| | - Elhussiny Aboulnaga
- Qingdao Institute of Bioenergy and Bioprocess Technology; Chinese Academy of Sciences, CAS Key Laboratory of Bio-based Materials; No. 189 Songling Road Qingdao 266101 China
- Mansoura University; Faculty of Agriculture; No. 60 Elgomhouria St. Mansoura 35516 Egypt
| | - Huizhou Liu
- Qingdao Institute of Bioenergy and Bioprocess Technology; Chinese Academy of Sciences, CAS Key Laboratory of Bio-based Materials; No. 189 Songling Road Qingdao 266101 China
| | - Tao Cheng
- Qingdao Institute of Bioenergy and Bioprocess Technology; Chinese Academy of Sciences, CAS Key Laboratory of Bio-based Materials; No. 189 Songling Road Qingdao 266101 China
| | - Mo Xian
- Qingdao Institute of Bioenergy and Bioprocess Technology; Chinese Academy of Sciences, CAS Key Laboratory of Bio-based Materials; No. 189 Songling Road Qingdao 266101 China
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Isoprene Production on Enzymatic Hydrolysate of Peanut Hull Using Different Pretreatment Methods. BIOMED RESEARCH INTERNATIONAL 2016; 2016:4342892. [PMID: 27847814 PMCID: PMC5099492 DOI: 10.1155/2016/4342892] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 08/04/2016] [Accepted: 08/18/2016] [Indexed: 11/18/2022]
Abstract
The present study is about the use of peanut hull for isoprene production. In this study, two pretreatment methods, hydrogen peroxide-acetic acid (HPAC) and popping, were employed prior to enzymatic hydrolysis, which could destroy the lignocellulosic structure and accordingly improve the efficiency of enzymatic hydrolysis. It is proven that the isoprene production on enzymatic hydrolysate with HPAC pretreatment is about 1.9-fold higher than that of popping pretreatment. Moreover, through High Performance Liquid Chromatography (HPLC) analysis, the amount and category of inhibitors such as formic acid, acetic acid, and HMF were assayed and were varied in different enzymatic hydrolysates, which may be the reason leading to a decrease in isoprene production during fermentation. To further increase the isoprene yield, the enzymatic hydrolysate of HPAC was detoxified by activated carbon. As a result, using the detoxified enzymatic hydrolysate as the carbon source, the engineered strain YJM21 could accumulate 297.5 mg/L isoprene, which accounted for about 90% of isoprene production by YJM21 fermented on pure glucose (338.6 mg/L). This work is thought to be the first attempt on isoprene production by E. coli using peanut hull as the feedstock. More importantly, it also shows the prospect of peanut hull to be considered as an alternative feedstock for bio-based chemicals or biofuels production due to its easy access and high polysaccharide content.
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75
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Ye L, Lv X, Yu H. Engineering microbes for isoprene production. Metab Eng 2016; 38:125-138. [DOI: 10.1016/j.ymben.2016.07.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 07/13/2016] [Indexed: 01/12/2023]
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76
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Lv X, Wang F, Zhou P, Ye L, Xie W, Xu H, Yu H. Dual regulation of cytoplasmic and mitochondrial acetyl-CoA utilization for improved isoprene production in Saccharomyces cerevisiae. Nat Commun 2016; 7:12851. [PMID: 27650330 PMCID: PMC5036000 DOI: 10.1038/ncomms12851] [Citation(s) in RCA: 137] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Accepted: 08/08/2016] [Indexed: 12/18/2022] Open
Abstract
Microbial production of isoprene from renewable feedstock is a promising alternative to traditional petroleum-based processes. Currently, efforts to improve isoprenoid production in Saccharomyces cerevisiae mainly focus on cytoplasmic engineering, whereas comprehensive engineering of multiple subcellular compartments is rarely reported. Here, we propose dual metabolic engineering of cytoplasmic and mitochondrial acetyl-CoA utilization to boost isoprene synthesis in S. cerevisiae. This strategy increases isoprene production by 2.1-fold and 1.6-fold relative to the recombinant strains with solely mitochondrial or cytoplasmic engineering, respectively. By combining a modified reiterative recombination system for rapid pathway assembly, a two-phase culture process for dynamic metabolic regulation, and aerobic fed-batch fermentation for sufficient supply of acetyl-coA and carbon, we achieve 2527, mg l(-1) of isoprene, which is the highest ever reported in engineered eukaryotes. We propose this strategy as an efficient approach to enhancing isoprene production in yeast, which might open new possibilities for bioproduction of other value-added chemicals.
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Affiliation(s)
- Xiaomei Lv
- Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
| | - Fan Wang
- Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
| | - Pingping Zhou
- Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
| | - Lidan Ye
- Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China.,Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Zhejiang University, Hangzhou 310027, China
| | - Wenping Xie
- Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
| | - Haoming Xu
- Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
| | - Hongwei Yu
- Institute of Bioengineering, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China
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77
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Li Y, Wang G. Strategies of isoprenoids production in engineered bacteria. J Appl Microbiol 2016; 121:932-40. [DOI: 10.1111/jam.13237] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Revised: 06/24/2016] [Accepted: 07/14/2016] [Indexed: 01/04/2023]
Affiliation(s)
- Y. Li
- College of Pharmaceutical and Biological Engineering; Shenyang University of Chemical Technology; Shenyang China
| | - G. Wang
- Key Laboratory of Environmental and Applied Microbiology; Chinese Academy of Sciences; Chengdu China
- Environmental Microbiology Key Laboratory of Sichuan Province; Chengdu Institute of Biology; Chinese Academy of Sciences; Chengdu China
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78
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Yang J, Nie Q. Engineering Escherichia coli to convert acetic acid to β-caryophyllene. Microb Cell Fact 2016; 15:74. [PMID: 27149950 PMCID: PMC4857421 DOI: 10.1186/s12934-016-0475-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 04/27/2016] [Indexed: 12/02/2022] Open
Abstract
Background Under aerobic conditions, acetic acid is the major byproduct produced by E. coli during the fermentation. And acetic acid is detrimental to cell growth as it destroys transmembrane pH gradients. Hence, how to reduce the production of acetic acid and how to utilize it as a feedstock are of intriguing interest. In this study, we provided an evidence to produce β-caryophyllene by the engineered E. coli using acetic acid as the only carbon source. Results Firstly, to construct the robust acetate-utilizing strain, acetyl-CoA synthases from three different sources were introduced and screened in the E. coli. Secondly, to establish the engineered strains converting acetic acid to β-caryophyllene, acetyl-CoA synthase (ACS), β-caryophyllene synthase (QHS1) and geranyl diphosphate synthase (GPPS2) were co-expressed in the E. coli cells. Thirdly, to further enhance β-caryophyllene production from acetic acid, the heterologous MVA pathway was introduced into the cells. What’s more, acetoacetyl-CoA synthase (AACS) was also expressed in the cells to increase the precursor acetoacetyl-CoA and accordingly resulted in the increase of β-caryophyllene. The final genetically modified strain, YJM67, could accumulate the production of biomass and β-caryophyllene up to 12.6 and 1.05 g/L during 72 h, respectively, with a specific productivity of 1.15 mg h−1 g−1 dry cells, and the conversion efficiency of acetic acid to β-caryophyllene (gram to gram) reached 2.1 %. The yield of β-caryophyllene on acetic acid of this strain also reached approximately 5.6 % of the theoretical yield. Conclusions In the present study, a novel biosynthetic pathway for β-caryophyllene has been investigated by means of conversion of acetic acid to β-caryophyllene using an engineered Escherichia coli. This was the first successful attempt in β-caryophyllene production by E. coli using acetic acid as the only carbon source. Therefore, we have provided a new metabolic engineering tool for β-caryophyllene synthesis.
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Affiliation(s)
- Jianming Yang
- Key Lab of Plant Biotechnology in Universities of Shandong Province; College of Life Sciences, Qingdao Agricultural University, Qingdao, 266109, China. .,Key Lab of Applied Mycology, College of Life Sciences, Qingdao Agricultural University, No.700 Changcheng Road, Chengyang District, Qingdao, 266109, China.
| | - Qingjuan Nie
- Foreign Languages School, Qingdao Agricultural University, Qingdao, 266109, China
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79
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Liao P, Hemmerlin A, Bach TJ, Chye ML. The potential of the mevalonate pathway for enhanced isoprenoid production. Biotechnol Adv 2016; 34:697-713. [PMID: 26995109 DOI: 10.1016/j.biotechadv.2016.03.005] [Citation(s) in RCA: 152] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 03/12/2016] [Accepted: 03/14/2016] [Indexed: 01/03/2023]
Abstract
The cytosol-localised mevalonic acid (MVA) pathway delivers the basic isoprene unit isopentenyl diphosphate (IPP). In higher plants, this central metabolic intermediate is also synthesised by the plastid-localised methylerythritol phosphate (MEP) pathway. Both MVA and MEP pathways conspire through exchange of intermediates and regulatory interactions. Products downstream of IPP such as phytosterols, carotenoids, vitamin E, artemisinin, tanshinone and paclitaxel demonstrate antioxidant, cholesterol-reducing, anti-ageing, anticancer, antimalarial, anti-inflammatory and antibacterial activities. Other isoprenoid precursors including isoprene, isoprenol, geraniol, farnesene and farnesol are economically valuable. An update on the MVA pathway and its interaction with the MEP pathway is presented, including the improvement in the production of phytosterols and other isoprenoid derivatives. Such attempts are for instance based on the bioengineering of microbes such as Escherichia coli and Saccharomyces cerevisiae, as well as plants. The function of relevant genes in the MVA pathway that can be utilised in metabolic engineering is reviewed and future perspectives are presented.
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Affiliation(s)
- Pan Liao
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
| | - Andréa Hemmerlin
- Centre National de la Recherche Scientifique, UPR 2357, Institut de Biologie Moléculaire des Plantes, Université de Strasbourg, 67083 Strasbourg, France.
| | - Thomas J Bach
- Centre National de la Recherche Scientifique, UPR 2357, Institut de Biologie Moléculaire des Plantes, Université de Strasbourg, 67083 Strasbourg, France.
| | - Mee-Len Chye
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, China.
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80
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ATP citrate lyase mediated cytosolic acetyl-CoA biosynthesis increases mevalonate production in Saccharomyces cerevisiae. Microb Cell Fact 2016; 15:48. [PMID: 26939608 PMCID: PMC4778282 DOI: 10.1186/s12934-016-0447-1] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 02/23/2016] [Indexed: 12/05/2022] Open
Abstract
Background With increasing concern about the environmental impact of a petroleum based economy, focus has shifted towards greener production strategies including metabolic engineering of microbes for the conversion of plant-based feedstocks to second generation biofuels and industrial chemicals. Saccharomyces cerevisiae is an attractive host for this purpose as it has been extensively engineered for production of various fuels and chemicals. Many of the target molecules are derived from the central metabolite and molecular building block, acetyl-CoA. To date, it has been difficult to engineer S. cerevisiae to continuously convert sugars present in biomass-based feedstocks to acetyl-CoA derived products due to intrinsic physiological constraints—in respiring cells, the precursor pyruvate is directed away from the endogenous cytosolic acetyl-CoA biosynthesis pathway towards the mitochondria, and in fermenting cells pyruvate is directed towards the byproduct ethanol. In this study we incorporated an alternative mode of acetyl-CoA biosynthesis mediated by ATP citrate lyase (ACL) that may obviate such constraints. Results We characterized the activity of several heterologously expressed ACLs in crude cell lysates, and found that ACL from Aspergillus nidulans demonstrated the highest activity. We employed a push/pull strategy to shunt citrate towards ACL by deletion of the mitochondrial NAD+-dependent isocitrate dehydrogenase (IDH1) and engineering higher flux through the upper mevalonate pathway. We demonstrated that combining the two modifications increases accumulation of mevalonate pathway intermediates, and that both modifications are required to substantially increase production. Finally, we incorporated a block strategy by replacing the native ERG12 (mevalonate kinase) promoter with the copper-repressible CTR3 promoter to maximize accumulation of the commercially important molecule mevalonate. Conclusion By combining the push/pull/block strategies, we significantly improved mevalonate production. We anticipate that this strategy can be used to improve the efficiency with which industrial strains of S. cerevisiae convert feedstocks to acetyl-CoA derived fuels and chemicals. Electronic supplementary material The online version of this article (doi:10.1186/s12934-016-0447-1) contains supplementary material, which is available to authorized users.
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81
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A novel MVA-mediated pathway for isoprene production in engineered E. coli. BMC Biotechnol 2016; 16:5. [PMID: 26786050 PMCID: PMC4719670 DOI: 10.1186/s12896-016-0236-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Accepted: 01/13/2016] [Indexed: 01/12/2023] Open
Abstract
Background To 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. Results We 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. Conclusions In 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. Electronic supplementary material The online version of this article (doi:10.1186/s12896-016-0236-2) contains supplementary material, which is available to authorized users.
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82
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Liu W, Xu X, Zhang R, Cheng T, Cao Y, Li X, Guo J, Liu H, Xian M. Engineering Escherichia coli for high-yield geraniol production with biotransformation of geranyl acetate to geraniol under fed-batch culture. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:58. [PMID: 26973712 PMCID: PMC4787002 DOI: 10.1186/s13068-016-0466-5] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 02/19/2016] [Indexed: 05/09/2023]
Abstract
BACKGROUND Geraniol is an acyclic monoterpene alcohol, which exhibits good prospect as a gasoline alternative. Geraniol is naturally encountered in plants at low concentrations and an attractive target for microbial engineering. Geraniol has been heterologously produced in Escherichia coli, but the low titer hinders its industrial applications. Moreover, bioconversion of geraniol by E. coli remains largely unknown. RESULTS Recombinant overexpression of Ocimum basilicum geraniol synthase, Abies grandis geranyl diphosphate synthase, and a heterotic mevalonate pathway in E. coli BL21 (DE3) enabled the production of up to 68.6 ± 3 mg/L geraniol in shake flasks. Initial fed-batch fermentation only increased geraniol production to 78.8 mg/L. To further improve the production yield, the fermentation conditions were optimized. Firstly, 81.4 % of volatile geraniol was lost during the first 5 h of fermentation in a solvent-free system. Hence, isopropyl myristate was added to the culture medium to form an aqueous-organic two-phase culture system, which effectively prevented volatilization of geraniol. Secondly, most of geraniol was eventually biotransformed into geranyl acetate by E. coli, thus decreasing geraniol production. For the first time, we revealed the role of acetylesterase (Aes, EC 3.1.1.6) from E. coli in hydrolyzing geranyl acetate to geraniol, and production of geraniol was successfully increased to 2.0 g/L under controlled fermentation conditions. CONCLUSIONS An efficient geraniol production platform was established by overexpressing several key pathway proteins in engineered E. coli strain combined with a controlled fermentation system. About 2.0 g/L geraniol was obtained using our controllable aqueous-organic two-phase fermentation system, which is the highest yield to date. In addition, the interconversion between geraniol and geranyl acetate by E. coli was first elucidated. This study provided a new and promising strategy for geraniol biosynthesis, which laid a basis for large-scale industrial application.
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Affiliation(s)
- Wei Liu
- />CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China
- />Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 10090 China
- />University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Xin Xu
- />CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China
- />University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Rubing Zhang
- />CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China
- />University of Chinese Academy of Sciences, Beijing, 100049 China
| | - Tao Cheng
- />CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China
| | - Yujin Cao
- />CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China
| | - Xiaoxiao Li
- />CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China
| | - Jiantao Guo
- />Department of Chemistry, University of Nebraska–Lincoln, Lincoln, NE 68588 USA
| | - Huizhou Liu
- />CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China
| | - Mo Xian
- />CAS Key Laboratory of Bio-Based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China
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83
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Willrodt C, Hoschek A, Bühler B, Schmid A, Julsing MK. Decoupling production from growth by magnesium sulfate limitation boosts de novo limonene production. Biotechnol Bioeng 2015; 113:1305-14. [PMID: 26574166 DOI: 10.1002/bit.25883] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 11/08/2015] [Indexed: 01/23/2023]
Abstract
The microbial production of isoprenoids has recently developed into a prime example for successful bottom-up synthetic biology or top-down systems biology strategies. Respective fermentation processes typically rely on growing recombinant microorganisms. However, the fermentative production of isoprenoids has to compete with cellular maintenance and growth for carbon and energy. Non-growing but metabolically active E. coli cells were evaluated in this study as alternative biocatalyst configurations to reduce energy and carbon loss towards biomass formation. The use of non-growing cells in an optimized fermentation medium resulted in more than fivefold increased specific limonene yields on cell dry weight and glucose, as compared to the traditional growing-cell-approach. Initially, the stability of the resting-cell activity was limited. This instability was overcome via the optimization of the minimal fermentation medium enabling high and stable limonene production rates for up to 8 h and a high specific yield of ≥50 mg limonene per gram cell dry weight. Omitting MgSO4 from the fermentation medium was very promising to prohibit growth and allow high productivities. Applying a MgSO4 -limitation also improved limonene formation by growing cells during non-exponential growth involving a reduced biomass yield on glucose and a fourfold increase in specific limonene yields on biomass as compared to non-limited cultures. The control of microbial growth via the medium composition was identified as a key but yet underrated strategy for efficient isoprenoid production. Biotechnol. Bioeng. 2016;113: 1305-1314. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Christian Willrodt
- Department Solar Materials, Helmholtz Centre for Environmental Research (UFZ), Leipzig, Germany.,Department of Biochemical and Chemical Engineering, Laboratory of Chemical Biotechnology, TU Dortmund University, Dortmund, Germany
| | - Anna Hoschek
- Department of Biochemical and Chemical Engineering, Laboratory of Chemical Biotechnology, TU Dortmund University, Dortmund, Germany
| | - Bruno Bühler
- Department of Biochemical and Chemical Engineering, Laboratory of Chemical Biotechnology, TU Dortmund University, Dortmund, Germany
| | - Andreas Schmid
- Department Solar Materials, Helmholtz Centre for Environmental Research (UFZ), Leipzig, Germany.
| | - Mattijs K Julsing
- Department of Biochemical and Chemical Engineering, Laboratory of Chemical Biotechnology, TU Dortmund University, Dortmund, Germany
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84
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Design and preparation of natural layered silicate/bio-based elastomer nanocomposites with improved dispersion and interfacial interaction. POLYMER 2015. [DOI: 10.1016/j.polymer.2015.10.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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85
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Lantz AT, Cardiello JF, Gee TA, Richards MG, Rosenstiel TN, Fisher AJ. Biochemical characterization of an isoprene synthase from Campylopus introflexus (heath star moss). PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2015; 94:209-15. [PMID: 26113160 DOI: 10.1016/j.plaphy.2015.06.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 05/29/2015] [Accepted: 06/08/2015] [Indexed: 05/25/2023]
Abstract
Each year, plants emit terragram quantities of the reactive hydrocarbon isoprene (2-methyl-1,3-butadiene) into the earth's atmosphere. In isoprene-emitting plants, the enzyme isoprene synthase (ISPS) catalyzes the production of isoprene from the isoprenoid intermediate dimethylallyl diphosphate (DMADP). While isoprene is emitted from all major classes of land plants, to date ISPSs from angiosperms only have been characterized. Here, we report the identification and initial biochemical characterization of a DMADP-dependent ISPS from the isoprene-emitting bryophyte Campylopus introflexus (heath star moss). The partially-purified C. introflexus ISPS (CiISPS) exhibited a Km for DMADP of 0.37 ± 0.28 mM, a pH optimum of 8.6 ± 0.5, and a temperature optimum of 40 ± 3 °C in vitro. Like ISPSs from angiosperms, the CiISPS required the presence of a divalent cation. However, unlike angiosperm ISPSs, the CiISPS utilized Mn(2+) preferentially over Mg(2+). Efforts are currently underway in our laboratory to further purify the CiISPS and clone the cDNA sequence encoding this novel enzyme. Our discovery of the first bryophyte ISPS paves the way for future studies concerning the evolutionary origins of isoprene emission in land plants and may help generate new bryophyte model systems for physiological and biochemical research on plant isoprene function.
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Affiliation(s)
- Alexandra T Lantz
- Department of Chemistry, Willamette University, Salem, OR 97301, USA.
| | | | - Taylor A Gee
- Department of Chemistry, Willamette University, Salem, OR 97301, USA
| | | | - Todd N Rosenstiel
- Department of Biology, Portland State University, Portland, OR 97207, USA.
| | - Alison J Fisher
- Department of Chemistry, Willamette University, Salem, OR 97301, USA.
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86
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Liu DE, Cerretani C, Tellez R, Scheer AP, Sciamanna S, Bryan PF, Radke CJ, Prausnitz JM. Analysis of countercurrent membrane vapor extraction of a dilute aqueous biosolute. AIChE J 2015. [DOI: 10.1002/aic.14892] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- David E. Liu
- Dept. of Chemical and Biomolecular Engineering; University of California; Berkeley CA 94720
| | - Colin Cerretani
- Dept. of Chemical and Biomolecular Engineering; University of California; Berkeley CA 94720
| | - Rodrigo Tellez
- Dept. of Chemical and Biomolecular Engineering; University of California; Berkeley CA 94720
| | - Agnes P. Scheer
- Dept. of Chemical and Biomolecular Engineering; University of California; Berkeley CA 94720
| | - Steve Sciamanna
- Dept. of Chemical and Biomolecular Engineering; University of California; Berkeley CA 94720
| | - Paul F. Bryan
- Dept. of Chemical and Biomolecular Engineering; University of California; Berkeley CA 94720
| | - Clayton J. Radke
- Dept. of Chemical and Biomolecular Engineering; University of California; Berkeley CA 94720
| | - John M. Prausnitz
- Dept. of Chemical and Biomolecular Engineering; University of California; Berkeley CA 94720
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87
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Xie W, Lv X, Ye L, Zhou P, Yu H. Construction of lycopene-overproducing Saccharomyces cerevisiae by combining directed evolution and metabolic engineering. Metab Eng 2015; 30:69-78. [DOI: 10.1016/j.ymben.2015.04.009] [Citation(s) in RCA: 137] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 04/28/2015] [Accepted: 04/29/2015] [Indexed: 12/26/2022]
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88
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Khan NE, Nybo SE, Chappell J, Curtis WR. Triterpene hydrocarbon production engineered into a metabolically versatile host--Rhodobacter capsulatus. Biotechnol Bioeng 2015; 112:1523-32. [PMID: 25728701 DOI: 10.1002/bit.25573] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 01/14/2015] [Accepted: 02/11/2015] [Indexed: 11/08/2022]
Abstract
Triterpene hydrocarbon biosynthesis of the ancient algae Botryococcus braunii was installed into Rhodobacter capsulatus to explore the production of C30 hydrocarbon in a host capable of diverse growth habits-utilizing carbohydrate, sunlight or hydrogen (with CO2 fixation) as alternative energy feedstocks. Engineering an enhanced MEP pathway was also used to augment triterpene accumulation. Despite dramatically different sources of carbon and reducing power, nearly the same level of botryococcene or squalene (∼5 mg oil/g-dry-weight [gDW]) was achieved in small-scale aerobic heterotrophic, anaerobic photoheterotrophic, and aerobic chemoautotrophic growth conditions. A glucose fed-batch bioreactor reached 40 mg botryococcene/L (∼12 mg/gDW), while autotrophic bioreactor performance with CO2 , H2 , and O2 reached 110 mg/L (16.7 mg/gDW) during batch and 60 mg/L (23 mg/gDW) during continuous operation at a dilution rate corresponding to about 10% of μ(max). Batch and continuous autotrophic specific productivity was found to reach 0.5 and 0.32 mg triterpene/g DW/h, comparable to prior reports for terpene production driven by heterotrophic growth conditions. This demonstrates the feasibility of alternative feedstocks and trophic modes to provide comparable routes to biochemicals that do not rely on sugar.
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Affiliation(s)
- Nymul E Khan
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania, 16802
| | - S Eric Nybo
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky, 40536
| | - Joe Chappell
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky, 40536
| | - Wayne R Curtis
- Department of Chemical Engineering, The Pennsylvania State University, University Park, Pennsylvania, 16802.
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89
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Sun J, Alper HS. Metabolic engineering of strains: from industrial-scale to lab-scale chemical production. ACTA ACUST UNITED AC 2015; 42:423-36. [DOI: 10.1007/s10295-014-1539-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 11/06/2014] [Indexed: 12/11/2022]
Abstract
Abstract
A plethora of successful metabolic engineering case studies have been published over the past several decades. Here, we highlight a collection of microbially produced chemicals using a historical framework, starting with titers ranging from industrial scale (more than 50 g/L), to medium-scale (5–50 g/L), and lab-scale (0–5 g/L). Although engineered Escherichia coli and Saccharomyces cerevisiae emerge as prominent hosts in the literature as a result of well-developed genetic engineering tools, several novel native-producing strains are gaining attention. This review catalogs the current progress of metabolic engineering towards production of compounds such as acids, alcohols, amino acids, natural organic compounds, and others.
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Affiliation(s)
- Jie Sun
- grid.89336.37 0000000419369924 McKetta Department of Chemical Engineering The University of Texas at Austin 200 E Dean Keeton St. Stop C0400 78712 Austin TX USA
| | - Hal S Alper
- grid.89336.37 0000000419369924 McKetta Department of Chemical Engineering The University of Texas at Austin 200 E Dean Keeton St. Stop C0400 78712 Austin TX USA
- grid.89336.37 0000000419369924 Institute for Cellular and Molecular Biology The University of Texas at Austin 2500 Speedway Avenue 78712 Austin TX USA
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90
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Schwab W, Fischer T, Wüst M. Terpene glucoside production: Improved biocatalytic processes using glycosyltransferases. Eng Life Sci 2015. [DOI: 10.1002/elsc.201400156] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Wilfried Schwab
- Biotechnology of Natural ProductsLife Science Center WeihenstephanTechnische Universität München Freising Germany
| | - Thilo Fischer
- Biotechnology of Natural ProductsLife Science Center WeihenstephanTechnische Universität München Freising Germany
| | - Matthias Wüst
- Food Chemistry Research UnitInstitute of Nutrition and Food SciencesUniversity of Bonn Bonn Germany
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91
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Morais AR, Dworakowska S, Reis A, Gouveia L, Matos CT, Bogdał D, Bogel-Łukasik R. Chemical and biological-based isoprene production: Green metrics. Catal Today 2015. [DOI: 10.1016/j.cattod.2014.05.033] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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92
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Gupta D, Summers ML, Basu C. Engineering an isoprenoid pathway in Escherichia coli for production of 2-methyl-3-buten-2-ol: a potential biofuel. Mol Biotechnol 2014; 56:516-23. [PMID: 24271564 DOI: 10.1007/s12033-013-9721-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
2-Methyl-3-buten-2-ol (MBO) is a natural volatile 5-carbon alcohol produced by several pine species that have the potential to be used as biofuel. MBO has a high energy content making it superior to ethanol in terms of energy output, and due to its volatility and lower solubility in water, MBO is easier to recover than ethanol. Pine's MBO synthase enzyme utilizes the intermediate dimethylallyl pyrophosphate (DMAPP) produced by the methyl-erythritol-4-phosphate isoprenoid pathway for the production of MBO. In this study, we performed metabolic engineering of Escherichia coli to express an alternate mevalonate dependent pathway for production of DMAPP, along with a codon optimized Pinus sabiniana MBO synthase gene. This heterologous expressed pathway carried out the conversion of an acetyl CoA precursor to DMAPP leading to production of MBO.
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Affiliation(s)
- Dinesh Gupta
- Department of Biology, California State University, 18111 Nordoff Street, Northridge, Los Angeles, CA, USA
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93
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Yang J, Guo L. Biosynthesis of β-carotene in engineered E. coli using the MEP and MVA pathways. Microb Cell Fact 2014; 13:160. [PMID: 25403509 PMCID: PMC4239400 DOI: 10.1186/s12934-014-0160-x] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 10/31/2014] [Indexed: 01/28/2023] Open
Abstract
Background β-carotene is a carotenoid compound that has been widely used not only in the industrial production of pharmaceuticals but also as nutraceuticals, animal feed additives, functional cosmetics, and food colorants. Currently, more than 90% of commercial β-carotene is produced by chemical synthesis. Due to the growing public concern over food safety, the use of chemically synthesized β-carotene as food additives or functional cosmetic agents has been severely controlled in recent years. This has reignited the enthusiasm for seeking natural β-carotene in large-scale fermentative production by microorganisms. Results To increase β-carotene production by improving the isopentenyl pyrophosphate (IPP) and geranyl diphospate (GPP) concentration in the cell, the optimized MEP (methylerythritol 4-phosphate) pathway containing 1-deoxy-D-xylulose-5-phosphate synthase (DXS) and isopentenyl pyrophosphate isomerase (FNI) from Bacillus subtilis, geranyl diphosphate synthase (GPPS2) from Abies grandis have been co-expressed in an engineered E. coli strain. To further enhance the production of β-carotene, the hybrid MVA (mevalonate) pathway has been introduced into an engineered E. coli strain, co-expressed with the optimized MEP pathway and GPPS2. The final genetically modified strain, YJM49, can accumulate 122.4±6.2 mg/L β-carotene in flask culture, approximately 113-fold and 1.7 times greater than strain YJM39, which carries the native MEP pathway, and YJM45, which harbors the MVA pathway and the native MEP pathway, respectively. Subsequently, the fermentation process was optimized to enhance β-carotene production with a maximum titer of 256.8±10.4 mg/L. Finally, the fed-batch fermentation of β-carotene was evaluated using the optimized culture conditions. After induction for 56 h, the final engineered strain YJM49 accumulated 3.2 g/L β-carotene with a volumetric productivity of 0.37 mg/(L · h · OD600) in aerobic fed-batch fermentation, and the conversion efficiency of glycerol to β-carotene (gram to gram) reached 2.76%. Conclusions In this paper, by using metabolic engineering techniques, the more efficient biosynthetic pathway of β-carotene was successfully assembled in E. coli BL21(DE3) with the optimized MEP (methylerythritol 4-phosphate) pathway, the gene for GPPS2 from Abies grandis, the hybrid MVA (mevalonate) pathway and β-carotene synthesis genes from Erwinia herbicola. Electronic supplementary material The online version of this article (doi:10.1186/s12934-014-0160-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jianming Yang
- Key Lab of Applied Mycology, College of Life Sciences, Qingdao Agricultural University, No.700 Changcheng Road, Chengyang District, Qingdao, 266109, China.
| | - Lizhong Guo
- Key Lab of Applied Mycology, College of Life Sciences, Qingdao Agricultural University, No.700 Changcheng Road, Chengyang District, Qingdao, 266109, China.
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94
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Opgenorth PH, Korman TP, Bowie JU. A synthetic biochemistry molecular purge valve module that maintains redox balance. Nat Commun 2014; 5:4113. [PMID: 24936528 DOI: 10.1038/ncomms5113] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 05/14/2014] [Indexed: 12/19/2022] Open
Abstract
The greatest potential environmental benefit of metabolic engineering would be the production of high-volume commodity chemicals, such as biofuels. Yet, the high yields required for the economic viability of low-value chemicals is particularly hard to achieve in microbes owing to the myriad competing biochemical pathways. An alternative approach, which we call synthetic biochemistry, is to eliminate the organism by constructing biochemical pathways in vitro. Viable synthetic biochemistry, however, will require simple methods to replace the cellular circuitry that maintains cofactor balance. Here we design a simple purge valve module for maintaining NADP(+)/NADPH balance. We test the purge valve in the production of polyhydroxybutyryl bioplastic and isoprene--pathways where cofactor generation and utilization are unbalanced. We find that the regulatory system is highly robust to variations in cofactor levels and readily transportable. The molecular purge valve provides a step towards developing continuously operating, sustainable synthetic biochemistry systems.
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Affiliation(s)
- Paul H Opgenorth
- Department of Chemistry and Biochemistry, UCLA-DOE Institute for Genomics and Proteomics, Molecular Biology Institute, University of California, Los Angeles, California 90095-1570, USA
| | - Tyler P Korman
- Department of Chemistry and Biochemistry, UCLA-DOE Institute for Genomics and Proteomics, Molecular Biology Institute, University of California, Los Angeles, California 90095-1570, USA
| | - James U Bowie
- 1] Department of Chemistry and Biochemistry, UCLA-DOE Institute for Genomics and Proteomics, Molecular Biology Institute, University of California, Los Angeles, California 90095-1570, USA [2] Boyer Hall, UCLA, 611 Charles E Young Drive East, Los Angeles, California 90095-1570, USA
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95
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Xiong M, Schneiderman DK, Bates FS, Hillmyer MA, Zhang K. Scalable production of mechanically tunable block polymers from sugar. Proc Natl Acad Sci U S A 2014; 111:8357-62. [PMID: 24912182 PMCID: PMC4060720 DOI: 10.1073/pnas.1404596111] [Citation(s) in RCA: 120] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Development of sustainable and biodegradable materials is essential for future growth of the chemical industry. For a renewable product to be commercially competitive, it must be economically viable on an industrial scale and possess properties akin or superior to existing petroleum-derived analogs. Few biobased polymers have met this formidable challenge. To address this challenge, we describe an efficient biobased route to the branched lactone, β-methyl-δ-valerolactone (βMδVL), which can be transformed into a rubbery (i.e., low glass transition temperature) polymer. We further demonstrate that block copolymerization of βMδVL and lactide leads to a new class of high-performance polyesters with tunable mechanical properties. Key features of this work include the creation of a total biosynthetic route to produce βMδVL, an efficient semisynthetic approach that employs high-yielding chemical reactions to transform mevalonate to βMδVL, and the use of controlled polymerization techniques to produce well-defined PLA-PβMδVL-PLA triblock polymers, where PLA stands for poly(lactide). This comprehensive strategy offers an economically viable approach to sustainable plastics and elastomers for a broad range of applications.
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Affiliation(s)
- Mingyong Xiong
- Departments of Chemical Engineering and Materials Science and
| | | | - Frank S Bates
- Departments of Chemical Engineering and Materials Science and
| | - Marc A Hillmyer
- Chemistry, University of Minnesota, Minneapolis, MN 55455-0431
| | - Kechun Zhang
- Departments of Chemical Engineering and Materials Science and
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96
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Zhang H, Liu Q, Cao Y, Feng X, Zheng Y, Zou H, Liu H, Yang J, Xian M. Microbial production of sabinene--a new terpene-based precursor of advanced biofuel. Microb Cell Fact 2014; 13:20. [PMID: 24512040 PMCID: PMC3923588 DOI: 10.1186/1475-2859-13-20] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Accepted: 02/03/2014] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Sabinene, one kind of monoterpene, accumulated limitedly in natural organisms, is being explored as a potential component for the next generation of aircraft fuels. And demand for advanced fuels impels us to develop biosynthetic routes for the production of sabinene from renewable sugar. RESULTS In this study, sabinene was significantly produced by assembling a biosynthetic pathway using the methylerythritol 4-phosphate (MEP) or heterologous mevalonate (MVA) pathway combining the GPP and sabinene synthase genes in an engineered Escherichia coli strain. Subsequently, the culture medium and process conditions were optimized to enhance sabinene production with a maximum titer of 82.18 mg/L. Finally, the fed-batch fermentation of sabinene was evaluated using the optimized culture medium and process conditions, which reached a maximum concentration of 2.65 g/L with an average productivity of 0.018 g h⁻¹ g⁻¹ dry cells, and the conversion efficiency of glycerol to sabinene (gram to gram) reached 3.49%. CONCLUSIONS This is the first report of microbial synthesis of sabinene using an engineered E. coli strain with the renewable carbon source as feedstock. Therefore, a green and sustainable production strategy has been established for sabinene.
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Affiliation(s)
| | | | | | | | | | | | | | - Jianming Yang
- CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, No,189 Songling Road, Qingdao, Laoshan District 266101, China.
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97
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Liu H, Sun Y, Ramos KRM, Nisola GM, Valdehuesa KNG, Lee WK, Park SJ, Chung WJ. Combination of Entner-Doudoroff pathway with MEP increases isoprene production in engineered Escherichia coli. PLoS One 2013; 8:e83290. [PMID: 24376679 PMCID: PMC3869766 DOI: 10.1371/journal.pone.0083290] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Accepted: 11/11/2013] [Indexed: 11/18/2022] Open
Abstract
Embden-Meyerhof pathway (EMP) in tandem with 2-C-methyl-D-erythritol 4-phosphate pathway (MEP) is commonly used for isoprenoid biosynthesis in E. coli. However, this combination has limitations as EMP generates an imbalanced distribution of pyruvate and glyceraldehyde-3-phosphate (G3P). Herein, four glycolytic pathways—EMP, Entner-Doudoroff Pathway (EDP), Pentose Phosphate Pathway (PPP) and Dahms pathway were tested as MEP feeding modules for isoprene production. Results revealed the highest isoprene production from EDP containing modules, wherein pyruvate and G3P were generated simultaneously; isoprene titer and yield were more than three and six times higher than those of the EMP module, respectively. Additionally, the PPP module that generates G3P prior to pyruvate was significantly more effective than the Dahms pathway, in which pyruvate production precedes G3P. In terms of precursor generation and energy/reducing-equivalent supply, EDP+PPP was found to be the ideal feeding module for MEP. These findings may launch a new direction for the optimization of MEP-dependent isoprenoid biosynthesis pathways.
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Affiliation(s)
- Huaiwei Liu
- Energy and Environment Fusion Technology Center, Department of Energy and Biotechnology, Myongji University, Cheoin-gu, Yongin-si, Gyeonggi-do, Republic of Korea
| | - Yuanzhang Sun
- Energy and Environment Fusion Technology Center, Department of Energy and Biotechnology, Myongji University, Cheoin-gu, Yongin-si, Gyeonggi-do, Republic of Korea
| | - Kristine Rose M Ramos
- Energy and Environment Fusion Technology Center, Department of Energy and Biotechnology, Myongji University, Cheoin-gu, Yongin-si, Gyeonggi-do, Republic of Korea
| | - Grace M Nisola
- Energy and Environment Fusion Technology Center, Department of Energy and Biotechnology, Myongji University, Cheoin-gu, Yongin-si, Gyeonggi-do, Republic of Korea
| | - Kris Niño G Valdehuesa
- Energy and Environment Fusion Technology Center, Department of Energy and Biotechnology, Myongji University, Cheoin-gu, Yongin-si, Gyeonggi-do, Republic of Korea
| | - Won-Keun Lee
- Division of Bioscience and Bioinformatics, Myongji University, Cheoin-gu, Yongin-si, Gyeonggi-do, Republic of Korea
| | - Si Jae Park
- Energy and Environment Fusion Technology Center, Department of Energy and Biotechnology, Myongji University, Cheoin-gu, Yongin-si, Gyeonggi-do, Republic of Korea
| | - Wook-Jin Chung
- Energy and Environment Fusion Technology Center, Department of Energy and Biotechnology, Myongji University, Cheoin-gu, Yongin-si, Gyeonggi-do, Republic of Korea
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98
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Yuan Y, Yu J, Jiang C, Li M, Lin S, Wang X, Huang L. Functional diversity of genes for the biosynthesis of paeoniflorin and its derivatives in Paeonia. Int J Mol Sci 2013; 14:18502-19. [PMID: 24022687 PMCID: PMC3794792 DOI: 10.3390/ijms140918502] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 08/09/2013] [Accepted: 08/19/2013] [Indexed: 02/04/2023] Open
Abstract
The Paeonia root, with or without bark, are considered vital traditional Chinese medicine materials; the examples are those of Bai Shao, Chi Shao, and Dan Pi. In this study, we examine 24 genes and their expressions involved in the biosynthesis of paeoniflorin and its derivatives, which are active compounds of the Paeonia root, in Paeonia lactiflora and P. suffruticosa, as well as other related plants, Punica granatum, Rhus radicans, and Coriaria nepalensis. Our phylogenetic analyses suggest that these genes have functional diversity, and analysis of the transcriptional level shows paeoniflorin and gallic acid biosynthesis-related genes exhibit different transcription profiles in flowers, carpels, bark-free roots, and bark of P. lactiflora. The correlation analysis of gene expression and active compound contents support the idea that hydroxymethylglutaryl-CoA synthase and phosphomevalonate kinase in the mevalonate pathway and 3-dehydroquinate dehydratase/shikimate dehydrogenase in shikimate biosynthesis are potentially closely related to the accumulation of paeoniflorin and benzoylpaeoniflorin. Coupling gene diversity with chemical analysis, we show that paeoniflorin and its derived aromatic amino acids are predominant in bark.
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Affiliation(s)
- Yuan Yuan
- National Resource Center for Chinese Materia Medica, Academy of Chinese Medical Sciences, Beijing 100700, China; E-Mails: (Y.Y.); (C.J.); (M.L.); (S.L.)
| | - Jun Yu
- CAS Key Laboratory of Genome Sciences and Information, Beijing 100029, China; E-Mail:
| | - Chao Jiang
- National Resource Center for Chinese Materia Medica, Academy of Chinese Medical Sciences, Beijing 100700, China; E-Mails: (Y.Y.); (C.J.); (M.L.); (S.L.)
| | - Minhui Li
- National Resource Center for Chinese Materia Medica, Academy of Chinese Medical Sciences, Beijing 100700, China; E-Mails: (Y.Y.); (C.J.); (M.L.); (S.L.)
| | - Shufang Lin
- National Resource Center for Chinese Materia Medica, Academy of Chinese Medical Sciences, Beijing 100700, China; E-Mails: (Y.Y.); (C.J.); (M.L.); (S.L.)
| | - Xumin Wang
- CAS Key Laboratory of Genome Sciences and Information, Beijing 100029, China; E-Mail:
- Authors to whom correspondence should be addressed; E-Mails: (X.W.); (L.H.); Tel.: +86-10-8299-5400 (X.W.); +86-10-8404-4340 (L.H.); Fax: +86-10-8299-5401 (X.W.); +86-10-8402-7175 (L.H.)
| | - Luqi Huang
- National Resource Center for Chinese Materia Medica, Academy of Chinese Medical Sciences, Beijing 100700, China; E-Mails: (Y.Y.); (C.J.); (M.L.); (S.L.)
- Authors to whom correspondence should be addressed; E-Mails: (X.W.); (L.H.); Tel.: +86-10-8299-5400 (X.W.); +86-10-8404-4340 (L.H.); Fax: +86-10-8299-5401 (X.W.); +86-10-8402-7175 (L.H.)
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99
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Gene replacement and elimination using λRed- and FLP-based tool to re-direct carbon flux in acetogen biocatalyst during continuous CO2/H2 blend fermentation. ACTA ACUST UNITED AC 2013; 40:749-58. [DOI: 10.1007/s10295-013-1279-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2013] [Accepted: 04/23/2013] [Indexed: 10/26/2022]
Abstract
Abstract
A time- and cost-efficient two-step gene elimination procedure was used for acetogen Clostridium sp. MT1834 capable of fermenting CO2/H2 blend to 245 mM acetate (p < 0.005). The first step rendered the targeted gene replacement without affecting the total genome size. We replaced the acetate pta-ack cluster with synthetic bi-functional acetaldehyde-alcohol dehydrogenase (al-adh). Replacement of pta-ack with al-adh rendered initiation of 243 mM ethanol accumulation at the expense of acetate production during CO2/H2 blend continuous fermentation (p < 0.005). At the second step, al-adh was eliminated to reduce the genome size. Resulting recombinants accumulated 25 mM mevalonate in fermentation broth (p < 0.005). Cell duplication time for recombinants with reduced genome size decreased by 9.5 % compared to Clostridium sp. MT1834 strain under the same fermentation conditions suggesting better cell energy pool management in the absence of the ack-pta gene cluster in the engineered biocatalyst. If the first gene elimination step was used alone for spo0A gene replacement with two copies of synthetic formate dehydrogenase in recombinants with a shortened genome, mevalonate production was replaced with 76.5 mM formate production in a single step continuous CO2/H2 blend fermentation (p < 0.005) with cell duplication time almost nearing that of the wild strain.
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100
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Expression in Haloferax volcanii of 3-hydroxy-3-methylglutaryl coenzyme A synthase facilitates isolation and characterization of the active form of a key enzyme required for polyisoprenoid cell membrane biosynthesis in halophilic archaea. J Bacteriol 2013; 195:3854-62. [PMID: 23794621 DOI: 10.1128/jb.00485-13] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Enzymes of the isoprenoid biosynthetic pathway in halophilic archaea remain poorly characterized, and parts of the pathway remain cryptic. This situation may be explained, in part, by the difficulty of expressing active, functional recombinant forms of these enzymes. The use of newly available expression plasmids and hosts has allowed the expression and isolation of catalytically active Haloferax volcanii 3-hydroxy-3-methylglutaryl coenzyme A (CoA) synthase (EC 2.3.310). This accomplishment has permitted studies that represent, to the best of our knowledge, the first characterization of an archaeal hydroxymethylglutaryl CoA synthase. Kinetic characterization indicates that, under optimal assay conditions, which include 4 M KCl, the enzyme exhibits catalytic efficiency and substrate saturation at metabolite levels comparable to those reported for the enzyme from nonhalophilic organisms. This enzyme is unique in that it is the first hydroxymethylglutaryl CoA synthase that is insensitive to feedback substrate inhibition by acetoacetyl-CoA. The enzyme supports reaction catalysis in the presence of various organic solvents. Haloferax 3-hydroxy-3-methylglutaryl CoA synthase is sensitive to inactivation by hymeglusin, a specific inhibitor known to affect prokaryotic and eukaryotic forms of the enzyme, with experimentally determined Ki and kinact values of 570 ± 120 nM and 17 ± 3 min(-1), respectively. In in vivo experiments, hymeglusin blocks the propagation of H. volcanii cells, indicating the critical role that the mevalonate pathway plays in isoprenoid biosynthesis by these archaea.
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