1
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Huang W, Liu Y, Ma X, Ma C, Jiang Y, Su J. Rational Design for the Complete Synthesis of Stevioside in Saccharomyces cerevisiae. Microorganisms 2024; 12:1125. [PMID: 38930507 PMCID: PMC11206123 DOI: 10.3390/microorganisms12061125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Revised: 05/28/2024] [Accepted: 05/28/2024] [Indexed: 06/28/2024] Open
Abstract
Stevioside is a secondary metabolite of diterpenoid glycoside production in plants. It has been used as a natural sweetener in various foods because of its high sweetness and low-calorie content. In this study, we constructed a Saccharomyces cerevisiae strain for the complete synthesis of stevioside using a metabolic engineering strategy. Firstly, the synthesis pathway of steviol was modularly constructed in S. cerevisiae BY4742, and the precursor pathway was strengthened. The yield of steviol was used as an indicator to investigate the expression effect of different sources of diterpene synthases under different combinations, and the strains with further improved steviol yield were screened. Secondly, glycosyltransferases were heterologously expressed in this strain to produce stevioside, the sequence of glycosyltransferase expression was optimized, and the uridine diphosphate-glucose (UDP-Glc) supply was enhanced. Finally, the results showed that the strain SST-302III-ST2 produced 164.89 mg/L of stevioside in a shake flask experiment, and the yield of stevioside reached 1104.49 mg/L in an experiment employing a 10 L bioreactor with batch feeding, which was the highest yield reported. We constructed strains with a high production of stevioside, thus laying the foundation for the production of other classes of steviol glycosides and holding good prospects for application and promotion.
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Affiliation(s)
| | | | | | | | | | - Jianyu Su
- School of Life Science, Ning Xia University, Yinchuan 750000, China; (W.H.); (Y.L.); (X.M.); (C.M.); (Y.J.)
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2
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Biswas A, Kumari A, Gaikwad DS, Pandey DK. Revolutionizing Biological Science: The Synergy of Genomics in Health, Bioinformatics, Agriculture, and Artificial Intelligence. OMICS : A JOURNAL OF INTEGRATIVE BIOLOGY 2023; 27:550-569. [PMID: 38100404 DOI: 10.1089/omi.2023.0197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2023]
Abstract
With climate emergency, COVID-19, and the rise of planetary health scholarship, the binary of human and ecosystem health has been deeply challenged. The interdependence of human and nonhuman animal health is increasingly acknowledged and paving the way for new frontiers in integrative biology. The convergence of genomics in health, bioinformatics, agriculture, and artificial intelligence (AI) has ushered in a new era of possibilities and applications. However, the sheer volume of genomic/multiomics big data generated also presents formidable sociotechnical challenges in extracting meaningful biological, planetary health and ecological insights. Over the past few years, AI-guided bioinformatics has emerged as a powerful tool for managing, analyzing, and interpreting complex biological datasets. The advances in AI, particularly in machine learning and deep learning, have been transforming the fields of genomics, planetary health, and agriculture. This article aims to unpack and explore the formidable range of possibilities and challenges that result from such transdisciplinary integration, and emphasizes its radically transformative potential for human and ecosystem health. The integration of these disciplines is also driving significant advancements in precision medicine and personalized health care. This presents an unprecedented opportunity to deepen our understanding of complex biological systems and advance the well-being of all life in planetary ecosystems. Notwithstanding in mind its sociotechnical, ethical, and critical policy challenges, the integration of genomics, multiomics, planetary health, and agriculture with AI-guided bioinformatics opens up vast opportunities for transnational collaborative efforts, data sharing, analysis, valorization, and interdisciplinary innovations in life sciences and integrative biology.
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Affiliation(s)
- Aakanksha Biswas
- Amity Institute of Biotechnology, Amity University Jharkhand, Ranchi, India
| | - Aditi Kumari
- Amity Institute of Biotechnology, Amity University Jharkhand, Ranchi, India
| | - D S Gaikwad
- Amity Institute of Organic Agriculture, Amity University, Noida, India
| | - Dhananjay K Pandey
- Amity Institute of Biotechnology, Amity University Jharkhand, Ranchi, India
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3
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De novo engineering of a bacterial lifestyle program. Nat Chem Biol 2022; 19:488-497. [PMID: 36522463 DOI: 10.1038/s41589-022-01194-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 09/30/2022] [Indexed: 12/23/2022]
Abstract
Synthetic biology has shown remarkable potential to program living microorganisms for applications. However, a notable discrepancy exists between the current engineering practice-which focuses predominantly on planktonic cells-and the ubiquitous observation of microbes in nature that constantly alternate their lifestyles on environmental variations. Here we present the de novo construction of a synthetic genetic program that regulates bacterial life cycle and enables phase-specific gene expression. The program is orthogonal, harnessing an engineered protein from 45 candidates as the biofilm matrix building block. It is also highly controllable, allowing directed biofilm assembly and decomposition as well as responsive autonomous planktonic-biofilm phase transition. Coupling to synthesis modules, it is further programmable for various functional realizations that conjugate phase-specific biomolecular production with lifestyle alteration. This work establishes a versatile platform for microbial engineering across physiological regimes, thereby shedding light on a promising path for gene circuit applications in complex contexts.
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4
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Zomorrodi AR, Hemez C, Arranz-Gibert P, Wu T, Isaacs FJ, Segrè D. Computational design and engineering of an Escherichia coli strain producing the nonstandard amino acid para-aminophenylalanine. iScience 2022; 25:104562. [PMID: 35789833 PMCID: PMC9249619 DOI: 10.1016/j.isci.2022.104562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 05/16/2022] [Accepted: 06/02/2022] [Indexed: 11/16/2022] Open
Abstract
Introducing heterologous pathways into host cells constitutes a promising strategy for synthesizing nonstandard amino acids (nsAAs) to enable the production of proteins with expanded chemistries. However, this strategy has proven challenging, as the expression of heterologous pathways can disrupt cellular homeostasis of the host cell. Here, we sought to optimize the heterologous production of the nsAA para-aminophenylalanine (pAF) in Escherichia coli. First, we incorporated a heterologous pAF biosynthesis pathway into a genome-scale model of E. coli metabolism and computationally identified metabolic interventions in the host’s native metabolism to improve pAF production. Next, we explored different approaches of imposing these flux interventions experimentally and found that the upregulation of flux in the chorismate biosynthesis pathway through the elimination of feedback inhibition mechanisms could significantly raise pAF titers (∼20-fold) while maintaining a reasonable pAF production-growth rate trade-off. Overall, this study provides a promising strategy for the biosynthesis of nsAAs in engineered cells. Sought to optimize para-aminophenylalanine (pAF) production and growth in E. coli Identified interventions in the host native metabolism using genome-scale models Constructed multiple mutant strains involving gene knockouts and/or overexpressions Flux modification in chorismate biosynthesis pathway significantly raised pAF titer
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Affiliation(s)
- Ali R. Zomorrodi
- Mucosal Immunology and Biology Research Center, Pediatrics Department, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
- Bioinformatics Graduate Program, Boston University, Boston, MA, USA
| | - Colin Hemez
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
- Systems Biology Institute, Yale University, West Haven, CT, USA
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Pol Arranz-Gibert
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
- Systems Biology Institute, Yale University, West Haven, CT, USA
| | - Terrence Wu
- Yale West Campus Analytical Core, 600 West Campus Drive, West Haven, USA
| | - Farren J. Isaacs
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
- Systems Biology Institute, Yale University, West Haven, CT, USA
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
- Corresponding author
| | - Daniel Segrè
- Bioinformatics Graduate Program, Boston University, Boston, MA, USA
- Department of Biology, Boston University, Boston, MA, USA
- Department of Biomedical Engineering, Boston University, Boston, MA, USA
- Biological Design Center, Boston University, Boston, MA, USA
- Corresponding author
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5
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Wu T, Liu J, Li M, Zhang G, Liu L, Li X, Men X, Xian M, Zhang H. Improvement of sabinene tolerance of Escherichia coli using adaptive laboratory evolution and omics technologies. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:79. [PMID: 32346395 PMCID: PMC7181518 DOI: 10.1186/s13068-020-01715-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 04/13/2020] [Indexed: 05/28/2023]
Abstract
BACKGROUND Biosynthesis of sabinene, a bicyclic monoterpene, has been accomplished in engineered microorganisms by introducing heterologous pathways and using renewable sugar as a carbon source. However, the efficiency and titers of this method are limited by the low host tolerance to sabinene (in both eukaryotes and prokaryotes). RESULTS In this study, Escherichia coli BL21(DE3) was selected as the strain for adaptive laboratory evolution. The strain was evolved by serial passaging in the medium supplemented with gradually increasing concentration of sabinene, and the evolved strain XYF(DE3), which exhibited significant tolerance to sabinene, was obtained. Then, XYF(DE3) was used as the host for sabinene production and an 8.43-fold higher sabinene production was achieved compared with the parental BL21(DE3), reaching 191.76 mg/L. Whole genomes resequencing suggested the XYF(DE3) strain is a hypermutator. A comparative analysis of transcriptomes of XYF(DE3) and BL21(DE3) was carried out to reveal the mechanism underlying the improvement of sabinene tolerance, and 734 up-regulated genes and 857 down-regulated genes were identified. We further tested the roles of the identified genes in sabinene tolerance via reverse engineering. The results demonstrated that overexpressions of ybcK gene of the DLP12 family, the inner membrane protein gene ygiZ, and the methylmalonyl-CoA mutase gene scpA could increase sabinene tolerance of BL21(DE3) by 127.7%, 71.1%, and 75.4%, respectively. Furthermore, scanning electron microscopy was applied to monitor cell morphology. Under sabinene stress, the parental BL21(DE3) showed increased cell length, whereas XYF(DE3) showed normal cell morphology. In addition, overexpression of ybcK, ygiZ or scpA could partially rescue cell morphology under sabinene stress and overexpression of ygiZ or scpA could increase sabinene production in BL21(DE3). CONCLUSIONS This study not only obtained a sabinene-tolerant strain for microbial production of sabinene but also revealed potential regulatory mechanisms that are important for sabinene tolerance. In addition, for the first time, ybcK, ygiZ, and scpA were identified to be important for terpene tolerance in E. coli BL21(DE3).
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Affiliation(s)
- Tong Wu
- 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, 100049 China
| | - Jinfeng 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
- School of Life Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050 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, 100049 China
| | - Ge 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
| | - Lijuan 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
| | - Xing 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
| | - 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
| | - 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
| | - 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
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6
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In vivo evolutionary engineering of riboswitch with high-threshold for N-acetylneuraminic acid production. Metab Eng 2020; 59:36-43. [PMID: 31954846 DOI: 10.1016/j.ymben.2020.01.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 11/26/2019] [Accepted: 01/04/2020] [Indexed: 11/22/2022]
Abstract
Riboswitches with desired properties, such as sensitivity, threshold, dynamic range, is important for its application. However, the property change of a natural riboswitch is difficult due to the lack of the understanding of aptamer ligand binding properties and a proper screening method for both rational and irrational design. In this study, an effective method to change the threshold of riboswitch was established in vivo based on growth coupled screening by combining both positive and negative selections. The feasibility of the method was verified by the model library. Using this method, an N-acetylneuraminic acid (NeuAc) riboswitch was evolved and modified riboswitches with high threshold and large dynamic range were obtained. Then, using a new NeuAc riboswitch, both ribosome binding sites and key gene in NeuAc biosynthesis pathway were optimized. The highest NeuAc production of 14.32 g/l that has been reported using glucose as sole carbon source was obtained.
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7
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Roberts AD, Finnigan W, Wolde-Michael E, Kelly P, Blaker JJ, Hay S, Breitling R, Takano E, Scrutton NS. Synthetic biology for fibres, adhesives and active camouflage materials in protection and aerospace. MRS COMMUNICATIONS 2019; 9:486-504. [PMID: 31281737 PMCID: PMC6609449 DOI: 10.1557/mrc.2019.35] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 03/12/2019] [Indexed: 05/03/2023]
Abstract
Synthetic biology has huge potential to produce the next generation of advanced materials by accessing previously unreachable (bio)chemical space. In this prospective review, we take a snapshot of current activity in this rapidly developing area, focussing on prominent examples for high-performance applications such as those required for protective materials and the aerospace sector. The continued growth of this emerging field will be facilitated by the convergence of expertise from a range of diverse disciplines, including molecular biology, polymer chemistry, materials science and process engineering. This review highlights the most significant recent advances and address the cross-disciplinary challenges currently being faced.
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Affiliation(s)
- Aled D. Roberts
- Manchester Institute of Biotechnology, Manchester Synthetic Biology
Research Centre SYBIOCHEM, School of Chemistry, The University of Manchester,
Manchester, UK, M1 7DN
- Bio-Active Materials Group, School of Materials, The University of
Manchester, Manchester, UK, M13 9PL
| | - William Finnigan
- Manchester Institute of Biotechnology, Manchester Synthetic Biology
Research Centre SYBIOCHEM, School of Chemistry, The University of Manchester,
Manchester, UK, M1 7DN
| | - Emmanuel Wolde-Michael
- Manchester Institute of Biotechnology, Manchester Synthetic Biology
Research Centre SYBIOCHEM, School of Chemistry, The University of Manchester,
Manchester, UK, M1 7DN
| | - Paul Kelly
- Manchester Institute of Biotechnology, Manchester Synthetic Biology
Research Centre SYBIOCHEM, School of Chemistry, The University of Manchester,
Manchester, UK, M1 7DN
| | - Jonny J. Blaker
- Bio-Active Materials Group, School of Materials, The University of
Manchester, Manchester, UK, M13 9PL
| | - Sam Hay
- Manchester Institute of Biotechnology, Manchester Synthetic Biology
Research Centre SYBIOCHEM, School of Chemistry, The University of Manchester,
Manchester, UK, M1 7DN
| | - Rainer Breitling
- Manchester Institute of Biotechnology, Manchester Synthetic Biology
Research Centre SYBIOCHEM, School of Chemistry, The University of Manchester,
Manchester, UK, M1 7DN
| | - Eriko Takano
- Manchester Institute of Biotechnology, Manchester Synthetic Biology
Research Centre SYBIOCHEM, School of Chemistry, The University of Manchester,
Manchester, UK, M1 7DN
| | - Nigel S. Scrutton
- Manchester Institute of Biotechnology, Manchester Synthetic Biology
Research Centre SYBIOCHEM, School of Chemistry, The University of Manchester,
Manchester, UK, M1 7DN
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8
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de Paula RG, Antoniêto ACC, Ribeiro LFC, Srivastava N, O'Donovan A, Mishra PK, Gupta VK, Silva RN. Engineered microbial host selection for value-added bioproducts from lignocellulose. Biotechnol Adv 2019; 37:107347. [PMID: 30771467 DOI: 10.1016/j.biotechadv.2019.02.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Revised: 01/27/2019] [Accepted: 02/08/2019] [Indexed: 12/12/2022]
Abstract
Lignocellulose is a rich and sustainable globally available carbon source and is considered a prominent alternative raw material for producing biofuels and valuable chemical compounds. Enzymatic hydrolysis is one of the crucial steps of lignocellulose degradation. Cellulolytic and hemicellulolytic enzyme mixes produced by different microorganisms including filamentous fungi, yeasts and bacteria, are used to degrade the biomass to liberate monosaccharides and other compounds for fermentation or conversion to value-added products. During biomass pretreatment and degradation, toxic compounds are produced, and undesirable carbon catabolic repression (CCR) can occur. In order to solve this problem, microbial metabolic pathways and transcription factors involved have been investigated along with the application of protein engineering to optimize the biorefinery platform. Engineered Microorganisms have been used to produce specific enzymes to breakdown biomass polymers and metabolize sugars to produce ethanol as well other biochemical compounds. Protein engineering strategies have been used for modifying lignocellulolytic enzymes to overcome enzymatic limitations and improving both their production and functionality. Furthermore, promoters and transcription factors, which are key proteins in this process, are modified to promote microbial gene expression that allows a maximum performance of the hydrolytic enzymes for lignocellulosic degradation. The present review will present a critical discussion and highlight the aspects of the use of microorganisms to convert lignocellulose into value-added bioproduct as well combat the bottlenecks to make the biorefinery platform from lignocellulose attractive to the market.
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Affiliation(s)
- Renato Graciano de Paula
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | | | - Liliane Fraga Costa Ribeiro
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Neha Srivastava
- Department of Chemical Engineering & Technology, IIT (BHU), Varanasi 221005, U.P, India
| | - Anthonia O'Donovan
- School of Science and Computing, Galway-Mayo Institute of Technology, Galway, Ireland
| | - P K Mishra
- Department of Chemical Engineering & Technology, IIT (BHU), Varanasi 221005, U.P, India
| | - Vijai K Gupta
- ERA Chair of Green Chemistry, Department of Chemistry and Biotechnology, Tallinn University of Technology, 12618 Tallinn, Estonia.
| | - Roberto N Silva
- Department of Biochemistry and Immunology, Ribeirao Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil.
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9
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Wang Y, Liu Q, Weng H, Shi Y, Chen J, Du G, Kang Z. Construction of Synthetic Promoters by Assembling the Sigma Factor Binding -35 and -10 Boxes. Biotechnol J 2018; 14:e1800298. [PMID: 30457214 DOI: 10.1002/biot.201800298] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 10/24/2018] [Indexed: 12/12/2022]
Abstract
Promoter is one of the key elements in regulating gene expression. Many natural or synthetic promoters have been modulated by their cis- or tans-regulatory elements to confer instant gene expression change in responding to designated stimuli. In addition, bacterial cells also engage different sigma factors to control the gene expression network at different growth phases or in response to the changing environment and external stresses. In this study, a set of promoters that assimilate the endogenous regulation of different sigma factors σ70 , σ38 , σ32 , and σ24 are synthesized. Promoters are designed to contain two or more kinds of interlocking sigma factor binding sites. The most competitive sigma factors will be automatically selected by the cell to take over the synthetic promoters during the cell growth course. Some of the synthetic promoters exhibit very strong strengths under different conditions, including stationary phase, low temperature, acidic pH, and high osmotic pressure. Comparing to the T7 promoter, synthetic promoter P21285 achieved higher yields of L-asparaginase and acid urease in Escherichia coli. The research not only expands the synthetic biology toolbox but also provide another strategy to design and construct synthetic promoters in prokaryotes.
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Affiliation(s)
- Yang Wang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China.,The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Qingtao Liu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China.,The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Huanjiao Weng
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China.,The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Yanan Shi
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China.,The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Jian Chen
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China.,The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Guocheng Du
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China.,The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
| | - Zhen Kang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, China.,The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
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10
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Fontana J, Dong C, Ham JY, Zalatan JG, Carothers JM. Regulated Expression of sgRNAs Tunes CRISPRi in E. coli. Biotechnol J 2018; 13:e1800069. [PMID: 29635744 DOI: 10.1002/biot.201800069] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 02/27/2018] [Indexed: 01/21/2023]
Abstract
Methods for implementing dynamically-controlled multi-gene programs could expand capabilities to engineer metabolism for efficiently producing high-value compounds. This work explores whether CRISPRi repression can be tuned in E. coli through the regulated expression of the CRISPRi machinery. When dCas9 is not limiting, variations in sgRNA expression alone can lead to CRISPRi repression levels ranging from 5- to 300-fold. Titrating sgRNA expression over a 2.5-fold range results in 16-fold changes in reporter gene expression. Many different classes of genetic controllers can generate 2.5-fold differences in transcription, suggesting they may be integrated into dynamically-regulated CRISPRi circuits. Finally, CRISPRi cannot be reversed for up to 12 hours by expressing a competing sgRNA later in the growth phase, indicating that CRISPR-Cas:DNA interactions can be persistent in vivo. Collectively, these results identify genetic architectures for tuning CRISPRi repression through regulated sgRNA expression and suggest that dynamically-regulated CRISPRi systems targeting multiple genes may be within reach.
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Affiliation(s)
- Jason Fontana
- Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA, 98195, USA
- Center for Synthetic Biology, University of Washington, Seattle, WA, 98195, USA
| | - Chen Dong
- Center for Synthetic Biology, University of Washington, Seattle, WA, 98195, USA
- Department of Chemistry, University of Washington, Seattle, WA, 98195, USA
| | - Jennifer Y Ham
- Center for Synthetic Biology, University of Washington, Seattle, WA, 98195, USA
- Department of Chemical Engineering, University of Washington, Seattle, WA, 98195, USA
| | - Jesse G Zalatan
- Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA, 98195, USA
- Center for Synthetic Biology, University of Washington, Seattle, WA, 98195, USA
- Department of Chemistry, University of Washington, Seattle, WA, 98195, USA
| | - James M Carothers
- Molecular Engineering and Sciences Institute, University of Washington, Seattle, WA, 98195, USA
- Center for Synthetic Biology, University of Washington, Seattle, WA, 98195, USA
- Department of Chemical Engineering, University of Washington, Seattle, WA, 98195, USA
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11
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Patel S, Panchasara H, Braddick D, Gohil N, Singh V. Synthetic small RNAs: Current status, challenges, and opportunities. J Cell Biochem 2018; 119:9619-9639. [DOI: 10.1002/jcb.27252] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 06/20/2018] [Indexed: 12/25/2022]
Affiliation(s)
- Shreya Patel
- Department of Microbiology, Synthetic Biology Laboratory School of Biological Sciences and Biotechnology, Institute of Advanced Research, Koba Institutional Area Gandhinagar India
| | - Happy Panchasara
- Department of Microbiology, Synthetic Biology Laboratory School of Biological Sciences and Biotechnology, Institute of Advanced Research, Koba Institutional Area Gandhinagar India
| | | | - Nisarg Gohil
- Department of Microbiology, Synthetic Biology Laboratory School of Biological Sciences and Biotechnology, Institute of Advanced Research, Koba Institutional Area Gandhinagar India
| | - Vijai Singh
- Department of Microbiology, Synthetic Biology Laboratory School of Biological Sciences and Biotechnology, Institute of Advanced Research, Koba Institutional Area Gandhinagar India
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12
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Model order reduction of nonlinear parabolic PDE systems with moving boundaries using sparse proper orthogonal decomposition: Application to hydraulic fracturing. Comput Chem Eng 2018. [DOI: 10.1016/j.compchemeng.2018.02.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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13
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Findeiß S, Etzel M, Will S, Mörl M, Stadler PF. Design of Artificial Riboswitches as Biosensors. SENSORS 2017; 17:s17091990. [PMID: 28867802 PMCID: PMC5621056 DOI: 10.3390/s17091990] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 08/23/2017] [Accepted: 08/25/2017] [Indexed: 12/11/2022]
Abstract
RNA aptamers readily recognize small organic molecules, polypeptides, as well as other nucleic acids in a highly specific manner. Many such aptamers have evolved as parts of regulatory systems in nature. Experimental selection techniques such as SELEX have been very successful in finding artificial aptamers for a wide variety of natural and synthetic ligands. Changes in structure and/or stability of aptamers upon ligand binding can propagate through larger RNA constructs and cause specific structural changes at distal positions. In turn, these may affect transcription, translation, splicing, or binding events. The RNA secondary structure model realistically describes both thermodynamic and kinetic aspects of RNA structure formation and refolding at a single, consistent level of modelling. Thus, this framework allows studying the function of natural riboswitches in silico. Moreover, it enables rationally designing artificial switches, combining essentially arbitrary sensors with a broad choice of read-out systems. Eventually, this approach sets the stage for constructing versatile biosensors.
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Affiliation(s)
- Sven Findeiß
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, University Leipzig, Härtelstraße 16-18, 04107 Leipzig, Germany.
- Faculty of Computer Science, Research Group Bioinformatics and Computational Biology, University of Vienna, Währingerstraße 29, A-1090 Vienna, Austria.
- Faculty of Chemistry, Department of Theoretical Chemistry, University of Vienna, Währingerstraße 17, A-1090 Vienna, Austria.
| | - Maja Etzel
- Institute for Biochemistry, Leipzig University, Brüderstraße 34, 04103 Leipzig, Germany.
| | - Sebastian Will
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, University Leipzig, Härtelstraße 16-18, 04107 Leipzig, Germany.
- Faculty of Chemistry, Department of Theoretical Chemistry, University of Vienna, Währingerstraße 17, A-1090 Vienna, Austria.
- Institute for Biochemistry, Leipzig University, Brüderstraße 34, 04103 Leipzig, Germany.
| | - Mario Mörl
- Institute for Biochemistry, Leipzig University, Brüderstraße 34, 04103 Leipzig, Germany.
| | - Peter F Stadler
- Bioinformatics Group, Department of Computer Science, and Interdisciplinary Center for Bioinformatics, University Leipzig, Härtelstraße 16-18, 04107 Leipzig, Germany.
- Faculty of Chemistry, Department of Theoretical Chemistry, University of Vienna, Währingerstraße 17, A-1090 Vienna, Austria.
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, 04103 Leipzig, Germany.
- Max Planck Institute for Mathematics in the Sciences, Inselstraße 22, 04103 Leipzig, Germany.
- Fraunhofer Institute for Cell Therapy and Immunology, Perlickstrasse 1, 04103 Leipzig, Germany.
- Center for RNA in Technology and Health, University of Copenhagen, Grønnegårdsvej 3, 1870 Frederiksberg , Denmark.
- Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501, USA.
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14
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Etzel M, Mörl M. Synthetic Riboswitches: From Plug and Pray toward Plug and Play. Biochemistry 2017; 56:1181-1198. [PMID: 28206750 DOI: 10.1021/acs.biochem.6b01218] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In synthetic biology, metabolic engineering, and gene therapy, there is a strong demand for orthogonal or externally controlled regulation of gene expression. Here, RNA-based regulatory devices represent a promising emerging alternative to proteins, allowing a fast and direct control of gene expression, as no synthesis of regulatory proteins is required. Besides programmable ribozyme elements controlling mRNA stability, regulatory RNA structures in untranslated regions are highly interesting for engineering approaches. Riboswitches are especially well suited, as they show a modular composition of sensor and response elements, allowing a free combination of different modules in a plug-and-play-like mode. The sensor or aptamer domain specifically interacts with a trigger molecule as a ligand, modulating the activity of the adjacent response domain that controls the expression of the genes located downstream, in most cases at the level of transcription or translation. In this review, we discuss the recent advances and strategies for designing such synthetic riboswitches based on natural or artificial components and readout systems, from trial-and-error approaches to rational design strategies. As the past several years have shown dramatic development in this fascinating field of research, we can give only a limited overview of the basic riboswitch design principles that is far from complete, and we apologize for not being able to consider every successful and interesting approach described in the literature.
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Affiliation(s)
- Maja Etzel
- Institute for Biochemistry, Leipzig University , Brüderstrasse 34, 04103 Leipzig, Germany
| | - Mario Mörl
- Institute for Biochemistry, Leipzig University , Brüderstrasse 34, 04103 Leipzig, Germany
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15
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France SP, Hepworth LJ, Turner NJ, Flitsch SL. Constructing Biocatalytic Cascades: In Vitro and in Vivo Approaches to de Novo Multi-Enzyme Pathways. ACS Catal 2016. [DOI: 10.1021/acscatal.6b02979] [Citation(s) in RCA: 271] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Scott P. France
- School of Chemistry, Manchester
Institute of Biotechnology, The University of Manchester, 131 Princess
Street, Manchester M1 7DN, United Kingdom
| | - Lorna J. Hepworth
- School of Chemistry, Manchester
Institute of Biotechnology, The University of Manchester, 131 Princess
Street, Manchester M1 7DN, United Kingdom
| | - Nicholas J. Turner
- School of Chemistry, Manchester
Institute of Biotechnology, The University of Manchester, 131 Princess
Street, Manchester M1 7DN, United Kingdom
| | - Sabine L. Flitsch
- School of Chemistry, Manchester
Institute of Biotechnology, The University of Manchester, 131 Princess
Street, Manchester M1 7DN, United Kingdom
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16
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Lian H, Zeldes BM, Lipscomb GL, Hawkins AB, Han Y, Loder AJ, Nishiyama D, Adams MWW, Kelly RM. Ancillary contributions of heterologous biotin protein ligase and carbonic anhydrase for CO 2 incorporation into 3-hydroxypropionate by metabolically engineered Pyrococcus furiosus. Biotechnol Bioeng 2016; 113:2652-2660. [PMID: 27315782 DOI: 10.1002/bit.26033] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 05/11/2016] [Accepted: 06/05/2016] [Indexed: 12/18/2022]
Abstract
Acetyl-Coenzyme A carboxylase (ACC), malonyl-CoA reductase (MCR), and malonic semialdehyde reductase (MRS) convert HCO3- and acetyl-CoA into 3-hydroxypropionate (3HP) in the 3-hydroxypropionate/4-hydroxybutyrate carbon fixation cycle resident in the extremely thermoacidophilic archaeon Metallosphaera sedula. These three enzymes, when introduced into the hyperthermophilic archaeon Pyrococcus furiosus, enable production of 3HP from maltose and CO2 . Sub-optimal function of ACC was hypothesized to be limiting for production of 3HP, so accessory enzymes carbonic anhydrase (CA) and biotin protein ligase (BPL) from M. sedula were produced recombinantly in Escherichia coli to assess their function. P. furiosus lacks a native, functional CA, while the M. sedula CA (Msed_0390) has a specific activity comparable to other microbial versions of this enzyme. M. sedula BPL (Msed_2010) was shown to biotinylate the β-subunit (biotin carboxyl carrier protein) of the ACC in vitro. Since the native BPLs in E. coli and P. furiosus may not adequately biotinylate the M. sedula ACC, the carboxylase was produced in P. furiosus by co-expression with the M. sedula BPL. The baseline production strain, containing only the ACC, MCR, and MSR, grown in a CO2 -sparged bioreactor reached titers of approximately 40 mg/L 3HP. Strains in which either the CA or BPL accessory enzyme from M. sedula was added to the pathway resulted in improved titers, 120 or 370 mg/L, respectively. The addition of both M. sedula CA and BPL, however, yielded intermediate titers of 3HP (240 mg/L), indicating that the effects of CA and BPL on the engineered 3HP pathway were not additive, possible reasons for which are discussed. While further efforts to improve 3HP production by regulating gene dosage, improving carbon flux and optimizing bioreactor operation are needed, these results illustrate the ancillary benefits of accessory enzymes for incorporating CO2 into 3HP production in metabolically engineered P. furiosus, and hint at the important role that CA and BPL likely play in the native 3HP/4HB pathway in M. sedula. Biotechnol. Bioeng. 2016;113: 2652-2660. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Hong Lian
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina 27587
| | - Benjamin M Zeldes
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina 27587
| | - Gina L Lipscomb
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia
| | - Aaron B Hawkins
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina 27587
| | - Yejun Han
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina 27587
| | - Andrew J Loder
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina 27587
| | - Declan Nishiyama
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina 27587
| | - Michael W W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia
| | - Robert M Kelly
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina 27587.
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17
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Wu SG, Shimizu K, Tang JKH, Tang YJ. Facilitate Collaborations among Synthetic Biology, Metabolic Engineering and Machine Learning. CHEMBIOENG REVIEWS 2016. [DOI: 10.1002/cben.201500024] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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18
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Beck DAC, Carothers JM, Subramanian VR, Pfaendtner J. Data science: Accelerating innovation and discovery in chemical engineering. AIChE J 2016. [DOI: 10.1002/aic.15192] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- David A. C. Beck
- Department of Chemical Engineering; University of Washington; Seattle WA
- eScience Institute, University of Washington; Seattle WA
| | - James M. Carothers
- Department of Chemical Engineering; University of Washington; Seattle WA
| | | | - Jim Pfaendtner
- Department of Chemical Engineering; University of Washington; Seattle WA
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19
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Van Hove B, Love AM, Ajikumar PK, De Mey M. Programming Biology: Expanding the Toolset for the Engineering of Transcription. Synth Biol (Oxf) 2016. [DOI: 10.1007/978-3-319-22708-5_1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
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20
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Zhang C, Tsoi R, You L. Addressing biological uncertainties in engineering gene circuits. Integr Biol (Camb) 2015; 8:456-64. [PMID: 26674800 DOI: 10.1039/c5ib00275c] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Synthetic biology has grown tremendously over the past fifteen years. It represents a new strategy to develop biological understanding and holds great promise for diverse practical applications. Engineering of a gene circuit typically involves computational design of the circuit, selection of circuit components, and test and optimization of circuit functions. A fundamental challenge in this process is the predictable control of circuit function due to multiple layers of biological uncertainties. These uncertainties can arise from different sources. We categorize these uncertainties into incomplete quantification of parts, interactions between heterologous components and the host, or stochastic dynamics of chemical reactions and outline potential design strategies to minimize or exploit them.
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Affiliation(s)
- Carolyn Zhang
- Department of Biomedical Engineering, Duke University, Durham, North Carolina 27708, USA
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21
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Mitchell A, Bucchini F, Cochrane G, Denise H, ten Hoopen P, Fraser M, Pesseat S, Potter S, Scheremetjew M, Sterk P, Finn RD. EBI metagenomics in 2016--an expanding and evolving resource for the analysis and archiving of metagenomic data. Nucleic Acids Res 2015; 44:D595-603. [PMID: 26582919 PMCID: PMC4702853 DOI: 10.1093/nar/gkv1195] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 10/23/2015] [Indexed: 11/15/2022] Open
Abstract
EBI metagenomics (https://www.ebi.ac.uk/metagenomics/) is a freely available hub for the analysis and archiving of metagenomic and metatranscriptomic data. Over the last 2 years, the resource has undergone rapid growth, with an increase of over five-fold in the number of processed samples and consequently represents one of the largest resources of analysed shotgun metagenomes. Here, we report the status of the resource in 2016 and give an overview of new developments. In particular, we describe updates to data content, a complete overhaul of the analysis pipeline, streamlining of data presentation via the website and the development of a new web based tool to compare functional analyses of sequence runs within a study. We also highlight two of the higher profile projects that have been analysed using the resource in the last year: the oceanographic projects Ocean Sampling Day and Tara Oceans.
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Affiliation(s)
- Alex Mitchell
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, UK
| | - Francois Bucchini
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, UK
| | - Guy Cochrane
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, UK
| | - Hubert Denise
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, UK
| | - Petra ten Hoopen
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, UK
| | - Matthew Fraser
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, UK
| | - Sebastien Pesseat
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, UK
| | - Simon Potter
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, UK
| | - Maxim Scheremetjew
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, UK
| | - Peter Sterk
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, UK
| | - Robert D Finn
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Trust Genome Campus, Hinxton, Cambridgeshire, CB10 1SD, UK
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22
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Huang HH, Seeger C, Danielson UH, Lindblad P. Analysis of the leakage of gene repression by an artificial TetR-regulated promoter in cyanobacteria. BMC Res Notes 2015; 8:459. [PMID: 26387086 PMCID: PMC4575469 DOI: 10.1186/s13104-015-1425-0] [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: 06/29/2014] [Accepted: 09/08/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND There is a need for strong and tightly regulated promoters to construct more reliable and predictable genetic modules for synthetic biology and metabolic engineering. For this reason we have previously constructed a TetR regulated L promoter library for the cyanobacterium Synechocystis PCC 6803. In addition to the L03 promoter showing wide dynamic range of transcriptional regulation, we observed the L09 promoter as unique in high leaky gene expression under repressed conditions. In the present study, we attempted to identify the cause of L09 promoter leakage. TetR binding to the promoter was studied by theoretical simulations of DNA breathing dynamics and by surface plasmon resonance (SPR) biosensor technology to analyze the kinetics of the DNA-protein interactions. RESULTS DNA breathing dynamics of a promoter was computed with the extended nonlinear Peyrard-Bishop-Dauxois mesoscopic model to yield a DNA opening probability profile at a single nucleotide resolution. The L09 promoter was compared to the L10, L11, and L12 promoters that were point-mutated and different in repressed promoter strength. The difference between DNA opening probability profiles is trivial on the TetR binding site. Furthermore, the kinetic rate constants of TetR binding, as measured by SPR biosensor technology, to the respective promoters are practically identical. This suggests that a trivial difference in probability as low as 1 × 10(-4) cannot lead to detectable variations in the DNA-protein interactions. Higher probability at the downstream region of transcription start site of the L09 promoter compared to the L10, L11, and L12 promoters was observed. Having practically the same kinetics of binding to TetR, the leakage problem of the L09 promoter might be due to enhanced RNA Polymerase (RNAP)-promoter interactions in the downstream region. CONCLUSIONS Both theoretical and experimental analyses of the L09 promoter's leakage problem exclude a mechanism of reduced TetR binding but instead suggest enhanced RNAP binding. These results assist in creating more tightly regulated promoters for realizing synthetic biology and metabolic engineering in biotechnological applications.
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Affiliation(s)
- Hsin-Ho Huang
- Department of Chemistry - Ångström, Science for Life Laboratory, Microbial Chemistry, Uppsala University, P.O. Box 523, 751 20, Uppsala, Sweden.
| | - Christian Seeger
- Department of Chemistry - BMC, Uppsala University, P.O. Box 576, 751 23, Uppsala, Sweden.
| | - U Helena Danielson
- Department of Chemistry - BMC, Uppsala University, P.O. Box 576, 751 23, Uppsala, Sweden.
| | - Peter Lindblad
- Department of Chemistry - Ångström, Science for Life Laboratory, Microbial Chemistry, Uppsala University, P.O. Box 523, 751 20, Uppsala, Sweden.
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23
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Pathway mining-based integration of critical enzyme parts for de novo biosynthesis of steviolglycosides sweetener in Escherichia coli. Cell Res 2015; 26:258-61. [PMID: 26358188 DOI: 10.1038/cr.2015.111] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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24
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Takahashi MK, Hayes CA, Chappell J, Sun ZZ, Murray RM, Noireaux V, Lucks JB. Characterizing and prototyping genetic networks with cell-free transcription–translation reactions. Methods 2015; 86:60-72. [DOI: 10.1016/j.ymeth.2015.05.020] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 05/20/2015] [Accepted: 05/21/2015] [Indexed: 02/07/2023] Open
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25
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Li C, Ying LQ, Zhang SS, Chen N, Liu WF, Tao Y. Modification of targets related to the Entner-Doudoroff/pentose phosphate pathway route for methyl-D-erythritol 4-phosphate-dependent carotenoid biosynthesis in Escherichia coli. Microb Cell Fact 2015; 14:117. [PMID: 26264597 PMCID: PMC4534122 DOI: 10.1186/s12934-015-0301-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 07/20/2015] [Indexed: 01/09/2023] Open
Abstract
Background In engineered strains of Escherichia coli, bioconversion efficiency is determined by not only metabolic flux but also the turnover efficiency of relevant pathways. Methyl-d-erythritol 4-phosphate (MEP)-dependent carotenoid biosynthesis in E. coli requires efficient turnover of precursors and balanced flux among precursors, cofactors, and cellular energy. However, the imbalanced supply of glyceraldehyde 3-phosphate (G3P) and pyruvate precursors remains the major metabolic bottleneck. To address this problem, we manipulated various genetic targets related to the Entner–Doudoroff (ED)/pentose phosphate (PP) pathways. Systematic target modification was conducted to improve G3P and pyruvate use and rebalance the precursor and redox fluxes. Results Carotenoid production was improved to different degrees by modifying various targets in the Embden–Meyerhof–Parnas (EMP) and ED pathways, which directed metabolic flux from the EMP pathway towards the ED pathway. The improvements in yield were much greater when the MEP pathway was enhanced. The coordinated modification of ED and MEP pathway targets using gene expression enhancement and protein coupling strategies in the pgi deletion background further improved carotenoid synthesis. The fine-tuning of flux at the branch point between the ED and PP pathways was important for carotenoid biosynthesis. Deletion of pfkAB instead of pgi reduced the carotenoid yield. This suggested that anaplerotic flux of G3P and pyruvate might be necessary for carotenoid biosynthesis. Improved carotenoid yields were accompanied by increased biomass and decreased acetate overflow. Therefore, efficient use of G3P and pyruvate precursors resulted in a balance among carotenoid biosynthesis, cell growth, and by-product metabolism. Conclusions An efficient and balanced MEP-dependent carotenoid bioconversion strategy involving both the ED and PP pathways was implemented by the coordinated modification of diverse central metabolic pathway targets. In this strategy, enhancement of the ED pathway for efficient G3P and pyruvate turnover was crucial for carotenoid production. The anaplerotic role of the PP pathway was important to supply precursors for the ED pathway. A balanced metabolic flux distribution among precursor supply, NADPH generation, and by-product pathways was established. Electronic supplementary material The online version of this article (doi:10.1186/s12934-015-0301-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Chun Li
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China.
| | - Lan-Qing Ying
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China.
| | - Sha-Sha Zhang
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China. .,School of Life Science, University of Chinese Academy of Sciences, Beijing, People's Republic of China.
| | - Nan Chen
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China. .,School of Life Science, University of Chinese Academy of Sciences, Beijing, People's Republic of China.
| | - Wei-Feng Liu
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China.
| | - Yong Tao
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People's Republic of China.
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van Summeren-Wesenhagen PV, Voges R, Dennig A, Sokolowsky S, Noack S, Schwaneberg U, Marienhagen J. Combinatorial optimization of synthetic operons for the microbial production of p-coumaryl alcohol with Escherichia coli. Microb Cell Fact 2015; 14:79. [PMID: 26062542 PMCID: PMC4464236 DOI: 10.1186/s12934-015-0274-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 05/08/2015] [Indexed: 01/03/2023] Open
Abstract
Background Microbes are extensively engineered to produce compounds of biotechnological or pharmaceutical interest. However, functional integration of synthetic pathways into the respective host cell metabolism and optimization of heterologous gene expression for achieving high product titers is still a challenging task. In this manuscript, we describe the optimization of a tetracistronic operon for the microbial production of the plant-derived phenylpropanoid p-coumaryl alcohol in Escherichia coli. Results Basis for the construction of a p-coumaryl alcohol producing strain was the development of Operon-PLICing as method for the rapid combinatorial assembly of synthetic operons. This method is based on the chemical cleavage reaction of phosphorothioate bonds in an iodine/ethanol solution to generate complementary, single-stranded overhangs and subsequent hybridization of multiple DNA-fragments. Furthermore, during the assembly of these DNA-fragments, Operon-PLICing offers the opportunity for balancing gene expression of all pathway genes on the level of translation for maximizing product titers by varying the spacing between the Shine-Dalgarno sequence and START codon. With Operon-PLICing, 81 different clones, each one carrying a different p-coumaryl alcohol operon, were individually constructed and screened for p-coumaryl alcohol formation within a few days. The absolute product titer of the best five variants ranged from 48 to 52 mg/L p-coumaryl alcohol without any further optimization of growth and production conditions. Conclusions Operon-PLICing is sequence-independent and thus does not require any specific recognition or target sequences for enzymatic activities since all hybridization sites can be arbitrarily selected. In fact, after PCR-amplification, no endonucleases or ligases, frequently used in other methods, are needed. The modularity, simplicity and robustness of Operon-PLICing would be perfectly suited for an automation of cloning in the microtiter plate format. Electronic supplementary material The online version of this article (doi:10.1186/s12934-015-0274-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Philana V van Summeren-Wesenhagen
- Institut für Bio- und Geowissenschaften, IBG-1: Biotechnologie and Bioeconomy Science Center (BioSC), Forschungszentrum Jülich, 52425, Jülich, Germany.
| | - Raphael Voges
- Institut für Bio- und Geowissenschaften, IBG-1: Biotechnologie and Bioeconomy Science Center (BioSC), Forschungszentrum Jülich, 52425, Jülich, Germany.
| | - Alexander Dennig
- Department of Chemistry, Organic and Bioorganic Chemistry, University of Graz, Heinrichstrasse 28, 8010, Graz, Austria.
| | - Sascha Sokolowsky
- Institut für Bio- und Geowissenschaften, IBG-1: Biotechnologie and Bioeconomy Science Center (BioSC), Forschungszentrum Jülich, 52425, Jülich, Germany.
| | - Stephan Noack
- Institut für Bio- und Geowissenschaften, IBG-1: Biotechnologie and Bioeconomy Science Center (BioSC), Forschungszentrum Jülich, 52425, Jülich, Germany.
| | - Ulrich Schwaneberg
- Lehrstuhl für Biotechnologie and Bioeconomy Science Center (BioSC), RWTH Aachen University, Worringer Weg 1, 52056, Aachen, Germany.
| | - Jan Marienhagen
- Institut für Bio- und Geowissenschaften, IBG-1: Biotechnologie and Bioeconomy Science Center (BioSC), Forschungszentrum Jülich, 52425, Jülich, Germany.
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Wallace S, Schultz EE, Balskus EP. Using non-enzymatic chemistry to influence microbial metabolism. Curr Opin Chem Biol 2015; 25:71-9. [PMID: 25579453 PMCID: PMC4380663 DOI: 10.1016/j.cbpa.2014.12.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 12/11/2014] [Accepted: 12/15/2014] [Indexed: 01/08/2023]
Abstract
The structural manipulation of small molecule metabolites occurs in all organisms and plays a fundamental role in essentially all biological processes. Despite an increasing interest in developing new, non-enzymatic chemical reactions capable of functioning in the presence of living organisms, the ability of such transformations to interface with cellular metabolism and influence biological function is a comparatively underexplored area of research. This review will discuss efforts to combine non-enzymatic chemistry with microbial metabolism. We will highlight recent and historical uses of non-biological reactions to study microbial growth and function, the use of non-enzymatic transformations to rescue auxotrophic microorganisms, and the combination of engineered microbial metabolism and biocompatible chemical reactions for organic synthesis.
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Affiliation(s)
- Stephen Wallace
- Department of Chemistry & Chemical Biology, Harvard University, 12 Oxford St, Cambridge, MA 02138, United States
| | - Erica E Schultz
- Department of Chemistry & Chemical Biology, Harvard University, 12 Oxford St, Cambridge, MA 02138, United States
| | - Emily P Balskus
- Department of Chemistry & Chemical Biology, Harvard University, 12 Oxford St, Cambridge, MA 02138, United States.
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Hoebenreich S, Zilly FE, Acevedo-Rocha CG, Zilly M, Reetz MT. Speeding up directed evolution: Combining the advantages of solid-phase combinatorial gene synthesis with statistically guided reduction of screening effort. ACS Synth Biol 2015; 4:317-31. [PMID: 24921161 DOI: 10.1021/sb5002399] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Efficient and economic methods in directed evolution at the protein, metabolic, and genome level are needed for biocatalyst development and the success of synthetic biology. In contrast to random strategies, semirational approaches such as saturation mutagenesis explore the sequence space in a focused manner. Although several combinatorial libraries based on saturation mutagenesis have been reported using solid-phase gene synthesis, direct comparison with traditional PCR-based methods is currently lacking. In this work, we compare combinatorial protein libraries created in-house via PCR versus those generated by commercial solid-phase gene synthesis. Using descriptive statistics and probabilistic distributions on amino acid occurrence frequencies, the quality of the libraries was assessed and compared, revealing that the outsourced libraries are characterized by less bias and outliers than the PCR-based ones. Afterward, we screened all libraries following a traditional algorithm for almost complete library coverage and compared this approach with an emergent statistical concept suggesting screening a lower portion of the protein sequence space. Upon analyzing the biocatalytic landscapes and best hits of all combinatorial libraries, we show that the screening effort could have been reduced in all cases by more than 50%, while still finding at least one of the best mutants.
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Affiliation(s)
- Sabrina Hoebenreich
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
- Fachbereich
Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße, 35032 Marburg, Germany
| | - Felipe E. Zilly
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Carlos G. Acevedo-Rocha
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
- Fachbereich
Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße, 35032 Marburg, Germany
| | - Matías Zilly
- Fakultät
für Physik, Universität Duisburg-Essen, Lotharstraße 1, 47048 Duisburg, Germany
| | - Manfred T. Reetz
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
- Fachbereich
Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße, 35032 Marburg, Germany
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29
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Stevens JT, Carothers JM. Designing RNA-based genetic control systems for efficient production from engineered metabolic pathways. ACS Synth Biol 2015; 4:107-15. [PMID: 25314371 DOI: 10.1021/sb400201u] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Engineered metabolic pathways can be augmented with dynamic regulatory controllers to increase production titers by minimizing toxicity and helping cells maintain homeostasis. We investigated the potential for dynamic RNA-based genetic control systems to increase production through simulation analysis of an engineered p-aminostyrene (p-AS) pathway in E. coli. To map the entire design space, we formulated 729 unique mechanistic models corresponding to all of the possible control topologies and mechanistic implementations in the system under study. Two thousand sampled simulations were performed for each of the 729 system designs to relate the potential effects of dynamic control to increases in p-AS production (total of 3 × 10(6) simulations). Our analysis indicates that dynamic control strategies employing aptazyme-regulated expression devices (aREDs) can yield >10-fold improvements over static control. We uncovered generalizable trends in successful control architectures and found that highly performing RNA-based control systems are experimentally tractable. Analyzing the metabolic control state space to predict optimal genetic control strategies promises to enhance the design of metabolic pathways.
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Affiliation(s)
- Jason T. Stevens
- Departments of Chemical Engineering and Bioengineering, Molecular Engineering & Sciences Institute, and Center for Synthetic Biology, University of Washington, Seattle, Washington 98195, United States
| | - James M. Carothers
- Departments of Chemical Engineering and Bioengineering, Molecular Engineering & Sciences Institute, and Center for Synthetic Biology, University of Washington, Seattle, Washington 98195, United States
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30
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Sparkman-Yager D, Correa-Rojas RA, Carothers JM. Kinetic folding design of aptazyme-regulated expression devices as riboswitches for metabolic engineering. Methods Enzymol 2015; 550:321-40. [PMID: 25605393 DOI: 10.1016/bs.mie.2014.10.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Recent developments in the fields of synthetic biology and metabolic engineering have opened the doors for the microbial production of biofuels and other valuable organic compounds. There remain, however, significant metabolic hurdles to the production of these compounds in cost-effective quantities. This is due, in part, to mismatches between the metabolic engineer's desire for high yields and the microbe's desire to survive. Many valuable compounds, or the intermediates necessary for their biosynthesis, prove deleterious at the desired production concentrations. One potential solution to these toxicity-related issues is the implementation of nonnative dynamic genetic control mechanisms that sense excessively high concentrations of metabolic intermediates and respond accordingly to alleviate their impact. One potential class of dynamic regulator is the riboswitch: cis-acting RNA elements that regulate the expression of downstream genes based on the presence of an effector molecule. Here, we present combined methods for constructing aptazyme-regulated expression devices (aREDs) through computational cotranscriptional kinetic folding design and experimental validation. These approaches can be used to engineer aREDs within novel genetic contexts for the predictable, dynamic regulation of gene expression in vivo.
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Affiliation(s)
- David Sparkman-Yager
- Department of Chemical Engineering, Molecular Engineering and Sciences Institute, Center for Synthetic Biology, University of Washington, Seattle, WA, USA
| | - Rodrigo A Correa-Rojas
- Department of Chemical Engineering, Molecular Engineering and Sciences Institute, Center for Synthetic Biology, University of Washington, Seattle, WA, USA
| | - James M Carothers
- Department of Chemical Engineering, Molecular Engineering and Sciences Institute, Center for Synthetic Biology, University of Washington, Seattle, WA, USA.
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31
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Characterizing Synthetic Biology Through Its Novel and Enhanced Functionalities. Synth Biol (Oxf) 2015. [DOI: 10.1007/978-3-319-02783-8_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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32
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The Chemistry-Biology-Medicine Continuum and the Drug Discovery and Development Process in Academia. ACTA ACUST UNITED AC 2014; 21:1039-45. [DOI: 10.1016/j.chembiol.2014.07.020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 06/30/2014] [Accepted: 07/21/2014] [Indexed: 12/21/2022]
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33
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Dai Z, Liu Y, Guo J, Huang L, Zhang X. Yeast synthetic biology for high-value metabolites. FEMS Yeast Res 2014; 15:1-11. [DOI: 10.1111/1567-1364.12187] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Revised: 04/30/2014] [Accepted: 07/15/2014] [Indexed: 01/08/2023] Open
Affiliation(s)
- Zhubo Dai
- Key Laboratory of Systems Microbial Biotechnology; Tianjin Institute of Industrial Biotechnology; Chinese Academy of Sciences; Tianjin China
| | - Yi Liu
- Key Laboratory of Systems Microbial Biotechnology; Tianjin Institute of Industrial Biotechnology; Chinese Academy of Sciences; Tianjin China
| | - Juan Guo
- National Resource Center for Chinese Materia Medica; China Academy of Chinese Medical Sciences; Beijing China
| | - Luqi Huang
- National Resource Center for Chinese Materia Medica; China Academy of Chinese Medical Sciences; Beijing China
| | - Xueli Zhang
- Key Laboratory of Systems Microbial Biotechnology; Tianjin Institute of Industrial Biotechnology; Chinese Academy of Sciences; Tianjin China
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34
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Song H, Ding MZ, Jia XQ, Ma Q, Yuan YJ. Synthetic microbial consortia: from systematic analysis to construction and applications. Chem Soc Rev 2014; 43:6954-81. [PMID: 25017039 DOI: 10.1039/c4cs00114a] [Citation(s) in RCA: 136] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Synthetic biology is an emerging research field that focuses on using rational engineering strategies to program biological systems, conferring on them new functions and behaviours. By developing genetic parts and devices based on transcriptional, translational, post-translational modules, many genetic circuits and metabolic pathways had been programmed in single cells. Extending engineering capabilities from single-cell behaviours to multicellular microbial consortia represents a new frontier of synthetic biology. Herein, we first reviewed binary interaction modes of microorganisms in microbial consortia and their underlying molecular mechanisms, which lay the foundation of programming cell-cell interactions in synthetic microbial consortia. Systems biology studies on cellular systems enable systematic understanding of diverse physiological processes of cells and their interactions, which in turn offer insights into the optimal design of synthetic consortia. Based on such fundamental understanding, a comprehensive array of synthetic microbial consortia constructed in the last decade were reviewed, including isogenic microbial communities programmed by quorum sensing-based cell-cell communications, sender-receiver microbial communities with one-way communications, and microbial ecosystems wired by two-way (bi-directional) communications. Furthermore, many applications including using synthetic microbial consortia for distributed bio-computations, chemicals and bioenergy production, medicine and human health, and environments were reviewed. Synergistic development of systems and synthetic biology will provide both a thorough understanding of naturally occurring microbial consortia and rational engineering of these complicated consortia for novel applications.
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Affiliation(s)
- Hao Song
- Key Laboratory of Systems Bioengineering, Ministry of Education, School of Chemical Engineering and Technology, and Collaborative Innovation Centre of Chemical Science and Engineering (Tianjin), Tianjin University, Tianjin 300072, P. R. China.
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35
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Fan LL, Li HJ, Chen QH. Applications and mechanisms of ionic liquids in whole-cell biotransformation. Int J Mol Sci 2014; 15:12196-216. [PMID: 25007820 PMCID: PMC4139838 DOI: 10.3390/ijms150712196] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 06/13/2014] [Accepted: 07/01/2014] [Indexed: 01/08/2023] Open
Abstract
Ionic liquids (ILs), entirely composed of cations and anions, are liquid solvents at room temperature. They are interesting due to their low vapor pressure, high polarity and thermostability, and also for the possibility to fine-tune their physicochemical properties through modification of the chemical structures of their cations or anions. In recent years, ILs have been widely used in biotechnological fields involving whole-cell biotransformations of biodiesel or biomass, and organic compound synthesis with cells. Research studies in these fields have increased from the past decades and compared to the typical solvents, ILs are the most promising alternative solvents for cell biotransformations. However, there are increasing limitations and new challenges in whole-cell biotransformations with ILs. There is little understanding of the mechanisms of ILs' interactions with cells, and much remains to be clarified. Further investigations are required to overcome the drawbacks of their applications and to broaden their application spectrum. This work mainly reviews the applications of ILs in whole-cell biotransformations, and the possible mechanisms of ILs in microbial cell biotransformation are proposed and discussed.
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Affiliation(s)
- Lin-Lin Fan
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310058, China.
| | - Hong-Ji Li
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310058, China.
| | - Qi-He Chen
- Department of Food Science and Nutrition, Zhejiang University, Hangzhou 310058, China.
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36
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Allouche D, André I, Barbe S, Davies J, de Givry S, Katsirelos G, O'Sullivan B, Prestwich S, Schiex T, Traoré S. Computational protein design as an optimization problem. ARTIF INTELL 2014. [DOI: 10.1016/j.artint.2014.03.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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37
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Improving the NADH-cofactor specificity of the highly active AdhZ3 and AdhZ2 from Escherichia coli K-12. J Biotechnol 2014; 189:157-65. [PMID: 24992211 DOI: 10.1016/j.jbiotec.2014.06.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 06/18/2014] [Accepted: 06/21/2014] [Indexed: 11/22/2022]
Abstract
Biocatalysis is a promising tool for the sustainable production of chemicals. When cofactor depending enzymatic reactions are involved the applicability of the right cofactor is a central issue. One important example in this regard is the production of alcohols by nicotinamide cofactor (NAD(P)(+)) depending alcohol dehydrogenases. AdhZ3 from Escherichia coli, which is important for the production of alcohols from biomass, has a preference for NADPH as cofactor. We used a structure guided site-specific random approach, to change the cofactor preference towards NADH and to deduce more general rules for redesigning the cofactor specificity. Transfer of a triplet motif from NADH preferring horse liver ADH to AdhZ3 showed an insufficient switch in the preference towards NADH. A combinatorial site saturation mutagenesis altering three residues at once was applied. Library screening with two different cofactor concentrations (0.1 and 0.3mM) resulted in nine improved variants with AdhZ3-LND having the highest vmax and AdhZ3-CND having the lowest K(m). Asparagine was the most frequent amino acid found in eight of nine triplet motifs. To verify the triplet-motif, two variants of E. coli AdhZ2 DIN and LND were designed and confirmed for improved activity with NADH.
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38
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Wallace S, Balskus EP. Opportunities for merging chemical and biological synthesis. Curr Opin Biotechnol 2014; 30:1-8. [PMID: 24747284 DOI: 10.1016/j.copbio.2014.03.006] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 03/23/2014] [Indexed: 12/23/2022]
Abstract
Organic chemists and metabolic engineers use largely orthogonal technologies to access small molecules like pharmaceuticals and commodity chemicals. As the use of biological catalysts and engineered organisms for chemical production grows, it is becoming increasingly evident that future efforts for chemical manufacture will benefit from the integration and unified expansion of these two fields. This review will discuss approaches that combine chemical and biological synthesis for small molecule production. We highlight recent advances in combining enzymatic and non-enzymatic catalysis in vitro, discuss the application of design principles from organic chemistry for engineering non-biological reactivity into enzymes, and describe the development of biocompatible chemistry that can be interfaced with microbial metabolism.
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Affiliation(s)
- Stephen Wallace
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, United States
| | - Emily P Balskus
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, United States.
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39
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Archer E, Süel GM. Synthetic biological networks. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2013; 76:096602. [PMID: 24006369 DOI: 10.1088/0034-4885/76/9/096602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Despite their obvious relationship and overlap, the field of physics is blessed with many insightful laws, while such laws are sadly absent in biology. Here we aim to discuss how the rise of a more recent field known as synthetic biology may allow us to more directly test hypotheses regarding the possible design principles of natural biological networks and systems. In particular, this review focuses on synthetic gene regulatory networks engineered to perform specific functions or exhibit particular dynamic behaviors. Advances in synthetic biology may set the stage to uncover the relationship of potential biological principles to those developed in physics.
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Affiliation(s)
- Eric Archer
- Green Center for Systems Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
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40
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Ogawa A. Ligand-Dependent Upregulation of Ribosomal Shunting. Chembiochem 2013; 14:1539-43, 1509. [DOI: 10.1002/cbic.201300362] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Indexed: 12/25/2022]
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41
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Design-driven, multi-use research agendas to enable applied synthetic biology for global health. SYSTEMS AND SYNTHETIC BIOLOGY 2013; 7:79-86. [PMID: 24432145 DOI: 10.1007/s11693-013-9118-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2012] [Revised: 04/24/2013] [Accepted: 07/09/2013] [Indexed: 01/03/2023]
Abstract
Many of the synthetic biological devices, pathways and systems that can be engineered are multi-use, in the sense that they could be used both for commercially-important applications and to help meet global health needs. The on-going development of models and simulation tools for assembling component parts into functionally-complex devices and systems will enable successful engineering with much less trial-and-error experimentation and laboratory infrastructure. As illustrations, I draw upon recent examples from my own work and the broader Keasling research group at the University of California Berkeley and the Joint BioEnergy Institute, of which I was formerly a part. By combining multi-use synthetic biology research agendas with advanced computer-aided design tool creation, it may be possible to more rapidly engineer safe and effective synthetic biology technologies that help address a wide range of global health problems.
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42
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Giese B, Koenigstein S, Wigger H, Schmidt JC, von Gleich A. Rational Engineering Principles in Synthetic Biology: A Framework for Quantitative Analysis and an Initial Assessment. ACTA ACUST UNITED AC 2013. [DOI: 10.1007/s13752-013-0130-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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43
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Lee SJ, Lee SJ, Lee DW. Design and development of synthetic microbial platform cells for bioenergy. Front Microbiol 2013; 4:92. [PMID: 23626588 PMCID: PMC3630320 DOI: 10.3389/fmicb.2013.00092] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 04/03/2013] [Indexed: 12/26/2022] Open
Abstract
The finite reservation of fossil fuels accelerates the necessity of development of renewable energy sources. Recent advances in synthetic biology encompassing systems biology and metabolic engineering enable us to engineer and/or create tailor made microorganisms to produce alternative biofuels for the future bio-era. For the efficient transformation of biomass to bioenergy, microbial cells need to be designed and engineered to maximize the performance of cellular metabolisms for the production of biofuels during energy flow. Toward this end, two different conceptual approaches have been applied for the development of platform cell factories: forward minimization and reverse engineering. From the context of naturally minimized genomes,non-essential energy-consuming pathways and/or related gene clusters could be progressively deleted to optimize cellular energy status for bioenergy production. Alternatively, incorporation of non-indigenous parts and/or modules including biomass-degrading enzymes, carbon uptake transporters, photosynthesis, CO2 fixation, and etc. into chassis microorganisms allows the platform cells to gain novel metabolic functions for bioenergy. This review focuses on the current progress in synthetic biology-aided pathway engineering in microbial cells and discusses its impact on the production of sustainable bioenergy.
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Affiliation(s)
- Sang Jun Lee
- Systems and Synthetic Biology Research Center, Korea Research Institute of Bioscience and Biotechnology Daejeon, South Korea
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44
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Buyel JF, Kaever T, Buyel JJ, Fischer R. Predictive models for the accumulation of a fluorescent marker protein in tobacco leaves according to the promoter/5'UTR combination. Biotechnol Bioeng 2013; 110:471-82. [PMID: 22948957 DOI: 10.1002/bit.24715] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Revised: 08/07/2012] [Accepted: 08/14/2012] [Indexed: 12/23/2022]
Abstract
The promoter and 5'-untranslated region (5'UTR) play a key role in determining the efficiency of recombinant protein expression in plants. Comparative experiments are used to identify suitable elements but these are usually tested in transgenic plants or in transformed protoplasts/suspension cells, so their relevance in whole-plant transient expression systems is unclear given the greater heterogeneity in expression levels among different leaves. Furthermore, little is known about the impact of promoter/5'UTR interactions on protein accumulation. We therefore established a predictive model using a design of experiments (DoE) approach to compare the strong double-enhanced Cauliflower mosaic virus 35S promoter (CaMV 35SS) and the weaker Agrobacterium tumefaciens Ti-plasmid nos promoter in whole tobacco plants transiently expressing the fluorescent marker protein DsRed. The promoters were combined with one of three 5'UTRs (one of which was tested with and without an additional protein targeting motif) and the accumulation of DsRed was measured following different post-agroinfiltration incubation periods in all leaves and at different leaf positions. The model predictions were quantitative, allowing the rapid identification of promoter/5'UTR combinations stimulating the highest and quickest accumulation of the marker protein in all leaves. The model also suggested that increasing the incubation time from 5 to 8 days would reduce batch-to-batch variability in protein yields. We used the model to identify promoter/5'UTR pairs that resulted in the least spatiotemporal variation in expression levels. These ideal pairs are suitable for the simultaneous, balanced production of several proteins in whole plants by transient expression.
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Affiliation(s)
- J F Buyel
- Institute for Molecular Biotechnology, Worringer Weg 1, RWTH Aachen University, Aachen 52074, Germany.
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45
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Sudrik C, Arha M, Cao J, Schaffer DV, Kane RS. Translational repression using BIV Tat peptide–TAR RNA interaction in mammalian cells. Chem Commun (Camb) 2013; 49:7457-9. [DOI: 10.1039/c3cc43086c] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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46
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Novel CAD-like enzymes from Escherichia coli K-12 as additional tools in chemical production. Appl Microbiol Biotechnol 2012; 97:5815-24. [PMID: 23093176 PMCID: PMC3684718 DOI: 10.1007/s00253-012-4474-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2012] [Revised: 09/21/2012] [Accepted: 09/24/2012] [Indexed: 12/30/2022]
Abstract
In analyzing the reductive power of Escherichia coli K-12 for metabolic engineering approaches, we identified YahK and YjgB, two medium-chain dehydrogenases/reductases subgrouped to the cinnamyl alcohol dehydrogenase family, as being important. Identification was achieved using a stepwise purification protocol starting with crude extract. For exact characterization, the genes were cloned into pET28a vector and expressed with N-terminal His tag. Substrate specificity studies revealed that a large variety of aldehydes but no ketones are converted by both enzymes. YahK and and YjgB strongly preferred NADPH as cofactor. The structure of YjgB was modeled using YahK as template for a comparison of the active center giving a first insight to the different substrate preferences. The enzyme activity for YahK, YjgB, and YqhD was determined on the basis of the temperature. YahK showed a constant increase in activity until 60 °C, whereas YjgB was most active between 37 and 50 °C. YqhD achieved the highest activity at 50 °C. Comparing YjgB and Yahk referring to the catalytic efficiency, YjgB achieved for almost all substrates higher rates (butyraldehyde 221 s−1 mM−1, benzaldehyde 1,305 s−1 mM−1). Exceptions are the two substrates glyceraldehydes (no activity for YjgB) and isobutyraldehyde (YjgB 0.26 s−1 mM−1) which are more efficiently converted by YahK (glyceraldehyde 2.8 s−1 mM−1, isobutyraldehyde 14.6 s−1 mM−1). YahK and even more so YjgB are good candidates for the reduction of aldehydes in metabolic engineering approaches and could replace the currently used YqhD.
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47
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Adkins J, Pugh S, McKenna R, Nielsen DR. Engineering microbial chemical factories to produce renewable "biomonomers". Front Microbiol 2012; 3:313. [PMID: 22969753 PMCID: PMC3430982 DOI: 10.3389/fmicb.2012.00313] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Accepted: 08/08/2012] [Indexed: 12/28/2022] Open
Abstract
By applying metabolic engineering tools and strategies to engineer synthetic enzyme pathways, the number and diversity of commodity and specialty chemicals that can be derived directly from renewable feedstocks is rapidly and continually expanding. This of course includes a number of monomer building-block chemicals that can be used to produce replacements to many conventional plastic materials. This review aims to highlight numerous recent and important advancements in the microbial production of these so-called "biomonomers." Relative to naturally-occurring renewable bioplastics, biomonomers offer several important advantages, including improved control over the final polymer structure and purity, the ability to synthesize non-natural copolymers, and allowing products to be excreted from cells which ultimately streamlines downstream recovery and purification. To highlight these features, a handful of biomonomers have been selected as illustrative examples of recent works, including polyamide monomers, styrenic vinyls, hydroxyacids, and diols. Where appropriate, examples of their industrial penetration to date and end-product uses are also highlighted. Novel biomonomers such as these are ultimately paving the way toward new classes of renewable bioplastics that possess a broader diversity of properties than ever before possible.
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Affiliation(s)
| | | | | | - David R. Nielsen
- Chemical Engineering, School for Engineering of Matter, Transport, and Energy, Arizona State UniversityTempe, AZ, USA
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48
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Ganesh I, Ravikumar S, Hong SH. Metabolically engineered Escherichia coli as a tool for the production of bioenergy and biochemicals from glycerol. BIOTECHNOL BIOPROC E 2012. [DOI: 10.1007/s12257-011-0446-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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49
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Pei L, Armstrong R, Danchin A, Porcar M. Biomaterials. Synth Biol (Oxf) 2012. [DOI: 10.1002/9783527659296.ch3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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50
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Abstract
Over the past decade, synthetic biology has emerged as an engineering discipline for biological systems. Compared with other substrates, biology poses a unique set of engineering challenges resulting from an incomplete understanding of natural biological systems and tools for manipulating them. To address these challenges, synthetic biology is advancing from developing proof-of-concept designs to focusing on core platforms for rational and high-throughput biological engineering. These platforms span the entire biological design cycle, including DNA construction, parts libraries, computational design tools, and interfaces for manipulating and probing synthetic circuits. The development of these enabling technologies requires an engineering mindset to be applied to biology, with an emphasis on generalizable techniques in addition to application-specific designs. This review aims to discuss the progress and challenges in synthetic biology and to illustrate areas where synthetic biology may impact biomedical engineering and human health.
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Affiliation(s)
- Allen A Cheng
- Synthetic Biology Group, Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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