1
|
Moon TS. SynMADE: synthetic microbiota across diverse ecosystems. Trends Biotechnol 2022; 40:1405-1414. [PMID: 36117027 DOI: 10.1016/j.tibtech.2022.08.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 08/12/2022] [Accepted: 08/22/2022] [Indexed: 01/21/2023]
Abstract
The past two decades have witnessed rapid advances in engineering individual microbial strains to produce biochemicals and biomaterials. However, engineering microbial consortia has been relatively slow. Using systems and synthetic biology approaches, researchers have been developing tools for engineering complex microbiota. In this opinion article, I discuss future directions and visions regarding developing microbiota as a biomanufacturing host. Specifically, I propose that we can develop the soil microbial community itself as a huge bioreactor. Ultimately, researchers will provide a generalizable system that enables us to understand a microbial consortium's interaction and metabolism on diverse temporal and spatial scales to address global problems, including the climate crisis, food inequality, the issue of waste, and sustainable bioproduction.
Collapse
Affiliation(s)
- Tae Seok Moon
- Department of Energy, Environmental and Chemical Engineering, Division of Biology and Biomedical Sciences, Washington University in St Louis, St Louis, MO 63130, USA.
| |
Collapse
|
2
|
Abstract
Regulatory processes in biology can be re-conceptualized in terms of logic gates, analogous to those in computer science. Frequently, biological systems need to respond to multiple, sometimes conflicting, inputs to provide the correct output. The language of logic gates can then be used to model complex signal transduction and metabolic processes. Advances in synthetic biology in turn can be used to construct new logic gates, which find a variety of biotechnology applications including in the production of high value chemicals, biosensing, and drug delivery. In this review, we focus on advances in the construction of logic gates that take advantage of biological catalysts, including both protein-based and nucleic acid-based enzymes. These catalyst-based biomolecular logic gates can read a variety of molecular inputs and provide chemical, optical, and electrical outputs, allowing them to interface with other types of biomolecular logic gates or even extend to inorganic systems. Continued advances in molecular modeling and engineering will facilitate the construction of new logic gates, further expanding the utility of biomolecular computing.
Collapse
|
3
|
Reprogramming microbial populations using a programmed lysis system to improve chemical production. Nat Commun 2021; 12:6886. [PMID: 34824227 PMCID: PMC8617184 DOI: 10.1038/s41467-021-27226-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Accepted: 11/10/2021] [Indexed: 11/08/2022] Open
Abstract
Microbial populations are a promising model for achieving microbial cooperation to produce valuable chemicals. However, regulating the phenotypic structure of microbial populations remains challenging. In this study, a programmed lysis system (PLS) is developed to reprogram microbial cooperation to enhance chemical production. First, a colicin M -based lysis unit is constructed to lyse Escherichia coli. Then, a programmed switch, based on proteases, is designed to regulate the effective lysis unit time. Next, a PLS is constructed for chemical production by combining the lysis unit with a programmed switch. As a result, poly (lactate-co-3-hydroxybutyrate) production is switched from PLH synthesis to PLH release, and the content of free PLH is increased by 283%. Furthermore, butyrate production with E. coli consortia is switched from E. coli BUT003 to E. coli BUT004, thereby increasing butyrate production to 41.61 g/L. These results indicate the applicability of engineered microbial populations for improving the metabolic division of labor to increase the efficiency of microbial cell factories.
Collapse
|
4
|
Cui S, Lv X, Xu X, Chen T, Zhang H, Liu Y, Li J, Du G, Ledesma-Amaro R, Liu L. Multilayer Genetic Circuits for Dynamic Regulation of Metabolic Pathways. ACS Synth Biol 2021; 10:1587-1597. [PMID: 34213900 DOI: 10.1021/acssynbio.1c00073] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The dynamic regulation of metabolic pathways is based on changes in external signals and endogenous changes in gene expression levels and has extensive applications in the field of synthetic biology and metabolic engineering. However, achieving dynamic control is not trivial, and dynamic control is difficult to obtain using simple, single-level, control strategies because they are often affected by native regulatory networks. Therefore, synthetic biologists usually apply the concept of logic gates to build more complex and multilayer genetic circuits that can process various signals and direct the metabolic flux toward the synthesis of the molecules of interest. In this review, we first summarize the applications of dynamic regulatory systems and genetic circuits and then discuss how to design multilayer genetic circuits to achieve the optimal control of metabolic fluxes in living cells.
Collapse
Affiliation(s)
- Shixiu Cui
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Xueqin Lv
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Xianhao Xu
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Taichi Chen
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Hongzhi Zhang
- Shandong Runde Biotechnology Co., Ltd., Tai’an 271000, China
| | - Yanfeng Liu
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Jianghua Li
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Guocheng Du
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Rodrigo Ledesma-Amaro
- Department of Bioengineering and Imperial College Centre for Synthetic Biology, Imperial College London, London SW7 2AZ, U.K
| | - Long Liu
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, China
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| |
Collapse
|
5
|
Zhang Y, Ding W, Wang Z, Zhao H, Shi S. Development of Host-Orthogonal Genetic Systems for Synthetic Biology. Adv Biol (Weinh) 2021; 5:e2000252. [PMID: 33729696 DOI: 10.1002/adbi.202000252] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 11/18/2020] [Indexed: 12/17/2022]
Abstract
The construction of a host-orthogonal genetic system can not only minimize the impact of host-specific nuances on fine-tuning of gene expression, but also expand cellular functions such as in vivo continuous evolution of genes based on an error-prone DNA polymerase. It represents an emerging powerful approach for making biology easier to engineer. In this review, the recent advances are described on the design of genetic systems that can be stably inherited in the host cells and are responsible for important biological processes including DNA replication, RNA transcription, protein translation, and gene regulation. Their applications in synthetic biology are summarized and the future challenges and opportunities are discussed in developing such systems.
Collapse
Affiliation(s)
- Yang Zhang
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Wentao Ding
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China.,Key Laboratory of Food Nutrition and Safety (Tianjin University of Science and Technology) Ministry of Education, College of Food Engineering and Biotechnology, Tianjin University of Science and Technology, No. 29, 13th Avenue, TEDA, Tianjin, 300457, P. R. China
| | - Zhihui Wang
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Huimin Zhao
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Shuobo Shi
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| |
Collapse
|
6
|
Wu Y, Chen T, Liu Y, Tian R, Lv X, Li J, Du G, Chen J, Ledesma-Amaro R, Liu L. Design of a programmable biosensor-CRISPRi genetic circuits for dynamic and autonomous dual-control of metabolic flux in Bacillus subtilis. Nucleic Acids Res 2020; 48:996-1009. [PMID: 31799627 PMCID: PMC6954435 DOI: 10.1093/nar/gkz1123] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 10/17/2019] [Accepted: 11/16/2019] [Indexed: 01/01/2023] Open
Abstract
Dynamic regulation is an effective strategy for fine-tuning metabolic pathways in order to maximize target product synthesis. However, achieving dynamic and autonomous up- and down-regulation of the metabolic modules of interest simultaneously, still remains a great challenge. In this work, we created an autonomous dual-control (ADC) system, by combining CRISPRi-based NOT gates with novel biosensors of a key metabolite in the pathway of interest. By sensing the levels of the intermediate glucosamine-6-phosphate (GlcN6P) and self-adjusting the expression levels of the target genes accordingly with the GlcN6P biosensor and ADC system enabled feedback circuits, the metabolic flux towards the production of the high value nutraceutical N-acetylglucosamine (GlcNAc) could be balanced and optimized in Bacillus subtilis. As a result, the GlcNAc titer in a 15-l fed-batch bioreactor increased from 59.9 g/l to 97.1 g/l with acetoin production and 81.7 g/l to 131.6 g/l without acetoin production, indicating the robustness and stability of the synthetic circuits in a large bioreactor system. Remarkably, this self-regulatory methodology does not require any external level of control such as the use of inducer molecules or switching fermentation/environmental conditions. Moreover, the proposed programmable genetic circuits may be expanded to engineer other microbial cells and metabolic pathways.
Collapse
Affiliation(s)
- Yaokang Wu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Taichi Chen
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Rongzhen Tian
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Xueqin Lv
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Jianghua Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Guocheng Du
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | - Jian Chen
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| | | | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi 214122, China
| |
Collapse
|
7
|
Hofmann A, Falk J, Prangemeier T, Happel D, Köber A, Christmann A, Koeppl H, Kolmar H. A tightly regulated and adjustable CRISPR-dCas9 based AND gate in yeast. Nucleic Acids Res 2019; 47:509-520. [PMID: 30476163 PMCID: PMC6326796 DOI: 10.1093/nar/gky1191] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 11/19/2018] [Indexed: 02/07/2023] Open
Abstract
The robust and precise on and off switching of one or more genes of interest, followed by expression or repression is essential for many biological circuits as well as for industrial applications. However, many regulated systems published to date influence the viability of the host cell, show high basal expression or enable only the overexpression of the target gene without the possibility of fine regulation. Herein, we describe an AND gate designed to overcome these limitations by combining the advantages of three well established systems, namely the scaffold RNA CRISPR/dCas9 platform that is controlled by Gal10 as a natural and by LexA-ER-AD as heterologous transcription factor. We hence developed a predictable and modular, versatile expression control system. The selection of a reporter gene set up combining a gene of interest (GOI) with a fluorophore by the ribosomal skipping T2A sequence allows to adapt the system to any gene of interest without losing reporter function. In order to obtain a better understanding of the underlying principles and the functioning of our system, we backed our experimental findings with the development of a mathematical model and single-cell analysis.
Collapse
Affiliation(s)
- Anja Hofmann
- Institute for Organic Chemistry and Biochemistry, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Johannes Falk
- Institute of Condensed Matter Physics, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - Tim Prangemeier
- Department of Electrical Engineering and Information Technology, Technische Universität Darmstadt, 64283 Darmstadt, Germany
| | - Dominic Happel
- Institute for Organic Chemistry and Biochemistry, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Adrian Köber
- Institute for Organic Chemistry and Biochemistry, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Andreas Christmann
- Institute for Organic Chemistry and Biochemistry, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Heinz Koeppl
- Department of Electrical Engineering and Information Technology, Technische Universität Darmstadt, 64283 Darmstadt, Germany
| | - Harald Kolmar
- Institute for Organic Chemistry and Biochemistry, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| |
Collapse
|
8
|
DeLorenzo DM, Moon TS. Construction of Genetic Logic Gates Based on the T7 RNA Polymerase Expression System in Rhodococcus opacus PD630. ACS Synth Biol 2019; 8:1921-1930. [PMID: 31362487 DOI: 10.1021/acssynbio.9b00213] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Rhodococcus opacus PD630 (R. opacus) is a nonmodel, Gram-positive bacterium that holds promise as a biological catalyst for the conversion of lignocellulosic biomass to value-added products. In particular, it demonstrates both a high tolerance for and an ability to consume inhibitory lignin-derived aromatics, generates large quantities of lipids, exhibits a relatively rapid growth rate, and has a growing genetic toolbox for engineering. However, the availability of genetic parts for tunable, high-activity gene expression is still limited in R. opacus. Furthermore, genetic logic circuits for sophisticated gene regulation have never been demonstrated in Rhodococcus spp. To address these shortcomings, two inducible T7 RNA polymerase-based expression systems were implemented for the first time in R. opacus and applied to the construction of AND and NAND genetic logic gates. Additionally, three isopropyl β-d-1-thiogalactopyranoside (IPTG)-inducible promoters were created by inserting LacI binding sites into newly characterized constitutive promoters. Furthermore, four novel aromatic sensors for 4-hydroxybenzoic acid, vanillic acid, sodium benzoate, and guaiacol were developed, expanding the gene expression toolbox. Finally, the T7 RNA polymerase platform was combined with a synthetic IPTG-inducible promoter to create an IMPLY logic gate. Overall, this work represents the first demonstration of a heterologous RNA polymerase system and synthetic genetic logic in R. opacus, enabling complex and tunable gene regulation in this promising nonmodel host for bioproduction.
Collapse
Affiliation(s)
- Drew M. DeLorenzo
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Tae Seok Moon
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
- Division of Biology and Biomedical Sciences, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| |
Collapse
|
9
|
Wehrs M, Tanjore D, Eng T, Lievense J, Pray TR, Mukhopadhyay A. Engineering Robust Production Microbes for Large-Scale Cultivation. Trends Microbiol 2019; 27:524-537. [PMID: 30819548 DOI: 10.1016/j.tim.2019.01.006] [Citation(s) in RCA: 119] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 01/11/2019] [Accepted: 01/23/2019] [Indexed: 11/27/2022]
Abstract
Systems biology and synthetic biology are increasingly used to examine and modulate complex biological systems. As such, many issues arising during scaling-up microbial production processes can be addressed using these approaches. We review differences between laboratory-scale cultures and larger-scale processes to provide a perspective on those strain characteristics that are especially important during scaling. Systems biology has been used to examine a range of microbial systems for their response in bioreactors to fluctuations in nutrients, dissolved gases, and other stresses. Synthetic biology has been used both to assess and modulate strain response, and to engineer strains to improve production. We discuss these approaches and tools in the context of their use in engineering robust microbes for applications in large-scale production.
Collapse
Affiliation(s)
- Maren Wehrs
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Institut für Genetik, Technische Universität Braunschweig, Braunschweig, Germany; Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA 94608, USA
| | - Deepti Tanjore
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Advanced Biofuels and Bioproducts Process Development Unit, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Thomas Eng
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA 94608, USA
| | | | - Todd R Pray
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Advanced Biofuels and Bioproducts Process Development Unit, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Aindrila Mukhopadhyay
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Joint BioEnergy Institute, Lawrence Berkeley National Laboratory, Emeryville, CA 94608, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
| |
Collapse
|
10
|
Moser F, Espah Borujeni A, Ghodasara AN, Cameron E, Park Y, Voigt CA. Dynamic control of endogenous metabolism with combinatorial logic circuits. Mol Syst Biol 2018; 14:e8605. [PMID: 30482789 PMCID: PMC6263354 DOI: 10.15252/msb.20188605] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 10/25/2018] [Accepted: 10/30/2018] [Indexed: 11/09/2022] Open
Abstract
Controlling gene expression during a bioprocess enables real-time metabolic control, coordinated cellular responses, and staging order-of-operations. Achieving this with small molecule inducers is impractical at scale and dynamic circuits are difficult to design. Here, we show that the same set of sensors can be integrated by different combinatorial logic circuits to vary when genes are turned on and off during growth. Three Escherichia coli sensors that respond to the consumption of feedstock (glucose), dissolved oxygen, and by-product accumulation (acetate) are constructed and optimized. By integrating these sensors, logic circuits implement temporal control over an 18-h period. The circuit outputs are used to regulate endogenous enzymes at the transcriptional and post-translational level using CRISPRi and targeted proteolysis, respectively. As a demonstration, two circuits are designed to control acetate production by matching their dynamics to when endogenous genes are expressed (pta or poxB) and respond by turning off the corresponding gene. This work demonstrates how simple circuits can be implemented to enable customizable dynamic gene regulation.
Collapse
Affiliation(s)
- Felix Moser
- Department of Biological Engineering, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Amin Espah Borujeni
- Department of Biological Engineering, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Amar N Ghodasara
- Department of Biological Engineering, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Ewen Cameron
- Department of Biological Engineering, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Yongjin Park
- Department of Biological Engineering, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Christopher A Voigt
- Department of Biological Engineering, Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, USA
| |
Collapse
|
11
|
Synthetic Gene Regulation in Cyanobacteria. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1080:317-355. [DOI: 10.1007/978-981-13-0854-3_13] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
|
12
|
Bittihn P, Din MO, Tsimring LS, Hasty J. Rational engineering of synthetic microbial systems: from single cells to consortia. Curr Opin Microbiol 2018; 45:92-99. [PMID: 29574330 DOI: 10.1016/j.mib.2018.02.009] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 02/06/2018] [Accepted: 02/19/2018] [Indexed: 12/11/2022]
Abstract
One promise of synthetic biology is to provide solutions for biomedical and industrial problems by rational design of added functionality in living systems. Microbes are at the forefront of this biological engineering endeavor due to their general ease of handling and their relevance in many potential applications from fermentation to therapeutics. In recent years, the field has witnessed an explosion of novel regulatory tools, from synthetic orthogonal transcription factors to posttranslational mechanisms for increased control over the behavior of synthetic circuits. Tool development has been paralleled by the discovery of principles that enable increased modularity and the management of host-circuit interactions. Engineered cell-to-cell communication bridges the scales from intracellular to population-level coordination. These developments facilitate the translation of more than a decade of circuit design into applications.
Collapse
Affiliation(s)
- Philip Bittihn
- BioCircuits Institute, University of California, San Diego, La Jolla, CA 92093, USA
| | - M Omar Din
- BioCircuits Institute, University of California, San Diego, La Jolla, CA 92093, USA
| | - Lev S Tsimring
- BioCircuits Institute, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jeff Hasty
- BioCircuits Institute, University of California, San Diego, La Jolla, CA 92093, USA; Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA; Molecular Biology Section, Division of Biological Science, University of California, San Diego, La Jolla, CA 92093, USA.
| |
Collapse
|
13
|
Xia PF, Li Q, Tan LR, Liu MM, Jin YS, Wang SG. Synthetic Whole-Cell Biodevices for Targeted Degradation of Antibiotics. Sci Rep 2018; 8:2906. [PMID: 29440690 PMCID: PMC5811551 DOI: 10.1038/s41598-018-21350-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 02/01/2018] [Indexed: 11/09/2022] Open
Abstract
Synthetic biology enables infinite possibilities in biotechnology via employing genetic modules. However, not many researches have explored the potentials of synthetic biology in environmental bioprocesses. In this study, we introduced a genetic module harboring the codon-optimized tetracycline degrading gene, tetX.co, into the model host, Escherichia coli, and generated a prototypal whole-cell biodevice for the degradation of a target antibiotic. Our results suggested that E. coli with the tetX.co-module driven by either the PJ23119 or PBAD promoters conferred resistance up to 50 μg/mL of tetracycline and degrades over 95% of tetracycline within 24 h. The detoxification ability of tetX was further verified in conditioned media by typical E. coli K-12 and B strains as well as Shewanella oneidensis. Our strategy demonstrated the feasibility of introducing genetic modules into model hosts to enable environmental functions, and this work will inspire more environmental innovations through synthetic biological devices.
Collapse
Affiliation(s)
- Peng-Fei Xia
- School of Environmental Science and Engineering, Shandong University, 27 Shanda Nanlu, Jinan, 250100, P.R. China
| | - Qian Li
- School of Environmental Science and Engineering, Shandong University, 27 Shanda Nanlu, Jinan, 250100, P.R. China
| | - Lin-Rui Tan
- School of Environmental Science and Engineering, Shandong University, 27 Shanda Nanlu, Jinan, 250100, P.R. China
| | - Miao-Miao Liu
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, 205 North Mathews Ave, Urbana, IL, 61801, United States
| | - Yong-Su Jin
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West Gregory Drive, Urbana, IL, 61801, United States.,Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, 905k South Goodwin Avenue, Urbana, IL, 61801, United States
| | - Shu-Guang Wang
- School of Environmental Science and Engineering, Shandong University, 27 Shanda Nanlu, Jinan, 250100, P.R. China.
| |
Collapse
|
14
|
Potential Applications of the Escherichia coli Heat Shock Response in Synthetic Biology. Trends Biotechnol 2018; 36:186-198. [DOI: 10.1016/j.tibtech.2017.10.014] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 10/20/2017] [Accepted: 10/20/2017] [Indexed: 01/06/2023]
|
15
|
Leistra AN, Amador P, Buvanendiran A, Moon-Walker A, Contreras LM. Rational Modular RNA Engineering Based on In Vivo Profiling of Structural Accessibility. ACS Synth Biol 2017; 6:2228-2240. [PMID: 28796489 DOI: 10.1021/acssynbio.7b00185] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Bacterial small RNAs (sRNAs) have been established as powerful parts for controlling gene expression. However, development and application of engineered sRNAs has primarily focused on regulating novel synthetic targets. In this work, we demonstrate a rational modular RNA engineering approach that uses in vivo structural accessibility measurements to tune the regulatory activity of a multisubstrate sRNA for differential control of its native target network. Employing the CsrB global sRNA regulator as a model system, we use published in vivo structural accessibility data to infer the contribution of its local structures (substructures) to function and select a subset for engineering. We then modularly recombine the selected substructures, differentially representing those of presumed high or low functional contribution, to build a library of 21 CsrB variants. Using fluorescent translational reporter assays, we demonstrate that the CsrB variants achieve a 5-fold gradient of control of well-characterized Csr network targets. Interestingly, results suggest that less conserved local structures within long, multisubstrate sRNAs may represent better targets for rational engineering than their well-conserved counterparts. Lastly, mapping the impact of sRNA variants on a signature Csr network phenotype indicates the potential of this approach for tuning the activity of global sRNA regulators in the context of metabolic engineering applications.
Collapse
Affiliation(s)
- Abigail N. Leistra
- McKetta
Department of Chemical Engineering, University of Texas at Austin, 200
E. Dean Keeton Street Stop C0400, Austin, Texas 78712, United States
| | - Paul Amador
- Microbiology
Graduate Program, University of Texas at Austin, 100 E. 24th Street
Stop A6500, Austin, Texas 78712, United States
| | - Aishwarya Buvanendiran
- Biological
Sciences Program College of Natural Sciences, University of Texas at Austin, 120 Inner Campus Drive Stop G2500, Austin, Texas 78712, United States
| | - Alex Moon-Walker
- Biological
Sciences Program College of Natural Sciences, University of Texas at Austin, 120 Inner Campus Drive Stop G2500, Austin, Texas 78712, United States
| | - Lydia M. Contreras
- McKetta
Department of Chemical Engineering, University of Texas at Austin, 200
E. Dean Keeton Street Stop C0400, Austin, Texas 78712, United States
| |
Collapse
|
16
|
DeLorenzo DM, Henson WR, Moon TS. Development of Chemical and Metabolite Sensors for Rhodococcus opacus PD630. ACS Synth Biol 2017; 6:1973-1978. [PMID: 28745867 DOI: 10.1021/acssynbio.7b00192] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Rhodococcus opacus PD630 is a nonmodel, Gram-positive bacterium that possesses desirable traits for biomass conversion, including consumption capabilities for lignocellulose-based sugars and toxic lignin-derived aromatic compounds, significant triacylglycerol accumulation, relatively rapid growth rate, and genetic tractability. However, few genetic elements have been directly characterized in R. opacus, limiting its application for lignocellulose bioconversion. Here, we report the characterization and development of genetic tools for tunable gene expression in R. opacus, including: (1) six fluorescent reporters for quantifying promoter output, (2) three chemically inducible promoters for variable gene expression, and (3) two classes of metabolite sensors derived from native R. opacus promoters that detect nitrogen levels or aromatic compounds. Using these tools, we also provide insights into native aromatic consumption pathways in R. opacus. Overall, this work expands the ability to control and characterize gene expression in R. opacus for future lignocellulose-based fuel and chemical production.
Collapse
Affiliation(s)
- Drew M. DeLorenzo
- Department of Energy, Environmental
and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - William R. Henson
- Department of Energy, Environmental
and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Tae Seok Moon
- Department of Energy, Environmental
and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| |
Collapse
|
17
|
Hoynes-O'Connor A, Shopera T, Hinman K, Creamer JP, Moon TS. Enabling complex genetic circuits to respond to extrinsic environmental signals. Biotechnol Bioeng 2017; 114:1626-1631. [PMID: 28262949 DOI: 10.1002/bit.26279] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Revised: 02/02/2017] [Accepted: 03/01/2017] [Indexed: 02/06/2023]
Abstract
Genetic circuits have the potential to improve a broad range of metabolic engineering processes and address a variety of medical and environmental challenges. However, in order to engineer genetic circuits that can meet the needs of these real-world applications, genetic sensors that respond to relevant extrinsic and intrinsic signals must be implemented in complex genetic circuits. In this work, we construct the first AND and NAND gates that respond to temperature and pH, two signals that have relevance in a variety of real-world applications. A previously identified pH-responsive promoter and a temperature-responsive promoter were extracted from the E. coli genome, characterized, and modified to suit the needs of the genetic circuits. These promoters were combined with components of the type III secretion system in Salmonella typhimurium and used to construct a set of AND gates with up to 23-fold change. Next, an antisense RNA was integrated into the circuit architecture to invert the logic of the AND gate and generate a set of NAND gates with up to 1168-fold change. These circuits provide the first demonstration of complex pH- and temperature-responsive genetic circuits, and lay the groundwork for the use of similar circuits in real-world applications. Biotechnol. Bioeng. 2017;114: 1626-1631. © 2017 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Allison Hoynes-O'Connor
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis 63130, One Brookings Dr., Box 1180, Missouri
| | - Tatenda Shopera
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis 63130, One Brookings Dr., Box 1180, Missouri
| | - Kristina Hinman
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis 63130, One Brookings Dr., Box 1180, Missouri
| | - John Philip Creamer
- Division of Biology and Biomedical Sciences, Washington University in St. Louis, St. Louis, Missouri
| | - Tae Seok Moon
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis 63130, One Brookings Dr., Box 1180, Missouri.,Division of Biology and Biomedical Sciences, Washington University in St. Louis, St. Louis, Missouri
| |
Collapse
|
18
|
Immethun CM, DeLorenzo DM, Focht CM, Gupta D, Johnson CB, Moon TS. Physical, chemical, and metabolic state sensors expand the synthetic biology toolbox for Synechocystis sp. PCC 6803. Biotechnol Bioeng 2017; 114:1561-1569. [PMID: 28244586 DOI: 10.1002/bit.26275] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2016] [Revised: 01/19/2017] [Accepted: 02/19/2017] [Indexed: 02/04/2023]
Abstract
Many under-developed organisms possess important traits that can boost the effectiveness and sustainability of microbial biotechnology. Photoautotrophic cyanobacteria can utilize the energy captured from light to fix carbon dioxide for their metabolic needs while living in environments not suited for growing crops. Various value-added compounds have been produced by cyanobacteria in the laboratory; yet, the products' titers and yields are often not industrially relevant and lag behind what have been accomplished in heterotrophic microbes. Genetic tools for biological process control are needed to take advantage of cyanobacteria's beneficial qualities, as tool development also lags behind what has been created in common heterotrophic hosts. To address this problem, we developed a suite of sensors that regulate transcription in the model cyanobacterium Synechocystis sp. PCC 6803 in response to metabolically relevant signals, including light and the cell's nitrogen status, and a family of sensors that respond to the inexpensive chemical, l-arabinose. Increasing the number of available tools enables more complex and precise control of gene expression. Expanding the synthetic biology toolbox for this cyanobacterium also improves our ability to utilize this important under-developed organism in biotechnology. Biotechnol. Bioeng. 2017;114: 1561-1569. © 2017 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Cheryl M Immethun
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri
| | - Drew M DeLorenzo
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri
| | - Caroline M Focht
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri
| | - Dinesh Gupta
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri
| | - Charles B Johnson
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri
| | - Tae Seok Moon
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri
| |
Collapse
|
19
|
Latimer LN, Dueber JE. Iterative optimization of xylose catabolism in Saccharomyces cerevisiae using combinatorial expression tuning. Biotechnol Bioeng 2017; 114:1301-1309. [PMID: 28165133 DOI: 10.1002/bit.26262] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 01/08/2017] [Accepted: 02/02/2017] [Indexed: 12/30/2022]
Abstract
A common challenge in metabolic engineering is rapidly identifying rate-controlling enzymes in heterologous pathways for subsequent production improvement. We demonstrate a workflow to address this challenge and apply it to improving xylose utilization in Saccharomyces cerevisiae. For eight reactions required for conversion of xylose to ethanol, we screened enzymes for functional expression in S. cerevisiae, followed by a combinatorial expression analysis to achieve pathway flux balancing and identification of limiting enzymatic activities. In the next round of strain engineering, we increased the copy number of these limiting enzymes and again tested the eight-enzyme combinatorial expression library in this new background. This workflow yielded a strain that has a ∼70% increase in biomass yield and ∼240% increase in xylose utilization. Finally, we chromosomally integrated the expression library. This library enriched for strains with multiple integrations of the pathway, which likely were the result of tandem integrations mediated by promoter homology. Biotechnol. Bioeng. 2017;114: 1301-1309. © 2017 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Luke N Latimer
- Department of Chemistry, University of California, Berkeley, California
| | - John E Dueber
- Department of Bioengineering, University of California, 2151 Berkeley Way, Berkeley, California 94720
| |
Collapse
|
20
|
Leitão AL, Costa MC, Enguita FJ. Applications of genome editing by programmable nucleases to the metabolic engineering of secondary metabolites. J Biotechnol 2016; 241:50-60. [PMID: 27845165 DOI: 10.1016/j.jbiotec.2016.11.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 11/06/2016] [Accepted: 11/10/2016] [Indexed: 12/17/2022]
Abstract
Genome engineering is a branch of modern biotechnology composed of a cohort of protocols designed to construct and modify a genotype with the main objective of giving rise to a desired phenotype. Conceptually, genome engineering is based on the so called genome editing technologies, a group of genetic techniques that allow either to delete or to insert genetic information in a particular genomic locus. Ten years ago, genome editing tools were limited to virus-driven integration and homologous DNA recombination. However, nowadays the uprising of programmable nucleases is rapidly changing this paradigm. There are two main families of modern tools for genome editing depending on the molecule that controls the specificity of the system and drives the editor machinery to its place of action. Enzymes such as Zn-finger and TALEN nucleases are protein-driven genome editors; while CRISPR system is a nucleic acid-guided editing system. Genome editing techniques are still not widely applied for the design of new compounds with pharmacological activity, but they are starting to be considered as promising tools for rational genome manipulation in biotechnology applications. In this review we will discuss the potential applications of programmable nucleases for the metabolic engineering of secondary metabolites with biological activity.
Collapse
Affiliation(s)
- Ana Lúcia Leitão
- Departamento de Ciências e Tecnologia da Biomassa, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Quinta da Torre, Campus de Caparica, 2829-516 Caparica, Portugal; MEtRICs, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Quinta da Torre, Campus de Caparica, 2829-516 Caparica, Portugal.
| | - Marina C Costa
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisboa, Portugal
| | - Francisco J Enguita
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisboa, Portugal.
| |
Collapse
|
21
|
Horbal L, Luzhetskyy A. Dual control system - A novel scaffolding architecture of an inducible regulatory device for the precise regulation of gene expression. Metab Eng 2016; 37:11-23. [PMID: 27040671 PMCID: PMC4915818 DOI: 10.1016/j.ymben.2016.03.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 03/29/2016] [Accepted: 03/30/2016] [Indexed: 12/17/2022]
Abstract
Here, we present a novel scaffolding architecture of an inducible regulatory device. This dual control system is completely silent in the off stage and is coupled to the regulation of gene expression at both the transcriptional and translational levels. This system also functions as an AND gate. We demonstrated the effectiveness of the cumate-riboswitch dual control system for the control of pamamycin production in Streptomyces albus. Placing the cre recombinase gene under the control of this system permitted the construction of synthetic devices with non-volatile memory that sense the signal and respond by altering DNA at the chromosomal level, thereby producing changes that are heritable. In addition, we present a library of synthetic inducible promoters based on the previously described cumate switch. With only one inducer and different promoters, we demonstrate that simultaneous modulation of the expression of several genes to different levels in various operons is possible. Because all modules of the AND gates are functional in bacteria other than Streptomyces, we anticipate that these regulatory devices can be used to control gene expression in other Actinobacteria. The features described in this study make these systems promising tools for metabolic engineering and biotechnology in Actinobacteria.
Collapse
Affiliation(s)
- L Horbal
- Helmholtz Institute for Pharmaceutical Research, 66123 Saarbrücken, Germany; University of Saarland, Pharmaceutical Biotechnology, 66123 Saarbrucken, Germany
| | - A Luzhetskyy
- Helmholtz Institute for Pharmaceutical Research, 66123 Saarbrücken, Germany; University of Saarland, Pharmaceutical Biotechnology, 66123 Saarbrucken, Germany.
| |
Collapse
|
22
|
Lee YJ, Hoynes-O'Connor A, Leong MC, Moon TS. Programmable control of bacterial gene expression with the combined CRISPR and antisense RNA system. Nucleic Acids Res 2016; 44:2462-73. [PMID: 26837577 PMCID: PMC4797300 DOI: 10.1093/nar/gkw056] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 01/20/2016] [Accepted: 01/20/2016] [Indexed: 12/16/2022] Open
Abstract
A central goal of synthetic biology is to implement diverse cellular functions by predictably controlling gene expression. Though research has focused more on protein regulators than RNA regulators, recent advances in our understanding of RNA folding and functions have motivated the use of RNA regulators. RNA regulators provide an advantage because they are easier to design and engineer than protein regulators, potentially have a lower burden on the cell and are highly orthogonal. Here, we combine the CRISPR system from Streptococcus pyogenes and synthetic antisense RNAs (asRNAs) in Escherichia coli strains to repress or derepress a target gene in a programmable manner. Specifically, we demonstrate for the first time that the gene target repressed by the CRISPR system can be derepressed by expressing an asRNA that sequesters a small guide RNA (sgRNA). Furthermore, we demonstrate that tunable levels of derepression can be achieved (up to 95%) by designing asRNAs that target different regions of a sgRNA and by altering the hybridization free energy of the sgRNA-asRNA complex. This new system, which we call the combined CRISPR and asRNA system, can be used to reversibly repress or derepress multiple target genes simultaneously, allowing for rational reprogramming of cellular functions.
Collapse
Affiliation(s)
- Young Je Lee
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Allison Hoynes-O'Connor
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Matthew C Leong
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Tae Seok Moon
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO, USA
| |
Collapse
|
23
|
Leitão AL, Enguita FJ. Editorial: Secondary Metabolism. An Unlimited Foundation for Synthetic Biology. Front Microbiol 2016; 6:1562. [PMID: 26793187 PMCID: PMC4709413 DOI: 10.3389/fmicb.2015.01562] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 12/23/2015] [Indexed: 11/15/2022] Open
Affiliation(s)
- Ana Lúcia Leitão
- MEtRICs, Departamento de Ciências e Tecnologia da Biomassa, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa Caparica, Portugal
| | - Francisco J Enguita
- Faculdade de Medicina, Instituto de Medicina Molecular, Universidade de Lisboa Lisboa, Portugal
| |
Collapse
|