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Peng X, Liu Y, Peng F, Wang T, Cheng Z, Chen Q, Li M, Xu L, Man Y, Zhang Z, Tan Y, Liu Z. Aptamer-controlled stimuli-responsive drug release. Int J Biol Macromol 2024; 279:135353. [PMID: 39245104 DOI: 10.1016/j.ijbiomac.2024.135353] [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: 06/12/2024] [Revised: 08/28/2024] [Accepted: 09/03/2024] [Indexed: 09/10/2024]
Abstract
Aptamers have been widely researched and applied in nanomedicine due to their programmable, activatable, and switchable properties. However, there are few reviews on aptamer-controlled stimuli-responsive drug delivery. This article highlights the mechanisms and advantages of aptamers in the construction of stimuli-responsive drug delivery systems. We summarize the assembly/reconfiguration mechanisms of aptamers in controlled release systems. The assembly and drug release strategies of drug delivery systems are illustrated. Specifically, we focus on the binding mechanisms to the target and the factors that induce/inhibit the binding to the stimuli, such as strand, pH, light, and temperature. The applications of aptamer-based stimuli-responsive drug release are elaborated. The challenges are discussed, and the future directions are proposed.
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Affiliation(s)
- Xingxing Peng
- Department of Pharmaceutics, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410013, Hunan Province, PR China
| | - Yanfei Liu
- Department of Pharmaceutical Engineering, College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, Hunan Province, PR China
| | - Feicheng Peng
- Hunan Institute for Drug Control, Changsha 410001, Hunan Province, PR China
| | - Ting Wang
- Department of Pharmaceutics, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410013, Hunan Province, PR China
| | - Zhongyu Cheng
- Department of Pharmaceutics, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410013, Hunan Province, PR China
| | - Qiwen Chen
- Department of Pharmaceutical Engineering, College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, Hunan Province, PR China
| | - Mingfeng Li
- Department of Pharmaceutics, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410013, Hunan Province, PR China
| | - Lishang Xu
- Department of Pharmaceutics, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410013, Hunan Province, PR China
| | - Yunqi Man
- Department of Pharmaceutics, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410013, Hunan Province, PR China
| | - Zhirou Zhang
- Department of Pharmaceutics, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410013, Hunan Province, PR China
| | - Yifu Tan
- Department of Pharmaceutics, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410013, Hunan Province, PR China
| | - Zhenbao Liu
- Department of Pharmaceutics, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410013, Hunan Province, PR China; Molecular Imaging Research Center of Central South University, Changsha 410008, Hunan, PR China.
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2
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Hwang HG, Ye DY, Jung GY. Biosensor-guided discovery and engineering of metabolic enzymes. Biotechnol Adv 2023; 69:108251. [PMID: 37690614 DOI: 10.1016/j.biotechadv.2023.108251] [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] [Received: 05/08/2023] [Revised: 09/04/2023] [Accepted: 09/05/2023] [Indexed: 09/12/2023]
Abstract
A variety of chemicals have been produced through metabolic engineering approaches, and enhancing biosynthesis performance can be achieved by using enzymes with high catalytic efficiency. Accordingly, a number of efforts have been made to discover enzymes in nature for various applications. In addition, enzyme engineering approaches have been attempted to suit specific industrial purposes. However, a significant challenge in enzyme discovery and engineering is the efficient screening of enzymes with the desired phenotype from extensive enzyme libraries. To overcome this bottleneck, genetically encoded biosensors have been developed to specifically detect target molecules produced by enzyme activity at the intracellular level. Especially, the biosensors facilitate high-throughput screening (HTS) of targeted enzymes, expanding enzyme discovery and engineering strategies with advances in systems and synthetic biology. This review examines biosensor-guided HTS systems and highlights studies that have utilized these tools to discover enzymes in diverse areas and engineer enzymes to enhance their properties, such as catalytic efficiency, specificity, and stability.
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Affiliation(s)
- Hyun Gyu Hwang
- Institute of Environmental and Energy Technology, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Dae-Yeol Ye
- Department of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Gyoo Yeol Jung
- Department of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 37673, Republic of Korea; School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 37673, Republic of Korea.
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3
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Qu H, Zheng M, Ma Q, Wang L, Mao Y, Eisenstein M, Tom Soh H, Zheng L. Allosteric Regulation of Aptamer Affinity through Mechano-Chemical Coupling. Angew Chem Int Ed Engl 2023; 62:e202214045. [PMID: 36646642 DOI: 10.1002/anie.202214045] [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: 09/22/2022] [Revised: 01/06/2023] [Accepted: 01/16/2023] [Indexed: 01/18/2023]
Abstract
The capacity to precisely modulate aptamer affinity is important for a wide variety of applications. However, most such engineering strategies entail laborious trial-and-error testing or require prior knowledge of an aptamer's structure and ligand-binding domain. We describe here a simple and generalizable strategy for allosteric modulation of aptamer affinity by employing a double-stranded molecular clamp that destabilizes aptamer secondary structure through mechanical tension. We demonstrate the effectiveness of the approach with a thrombin-binding aptamer and show that we can alter its affinity by as much as 65-fold. We also show that this modulation can be rendered reversible by introducing a restriction enzyme cleavage site into the molecular clamp domain and describe a design strategy for achieving even more finely-tuned affinity modulation. This strategy requires no prior knowledge of the aptamer's structure and binding mechanism and should thus be generalizable across aptamers.
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Affiliation(s)
- Hao Qu
- School of Food and Biological Engineering and Engineering Research Center of Bioprocess of Ministry of Education, Hefei University of Technology, Hefei, 230009, China
| | - Manyi Zheng
- School of Food and Biological Engineering and Engineering Research Center of Bioprocess of Ministry of Education, Hefei University of Technology, Hefei, 230009, China
| | - Qihui Ma
- School of Food and Biological Engineering and Engineering Research Center of Bioprocess of Ministry of Education, Hefei University of Technology, Hefei, 230009, China
| | - Lu Wang
- School of Food and Biological Engineering and Engineering Research Center of Bioprocess of Ministry of Education, Hefei University of Technology, Hefei, 230009, China
| | - Yu Mao
- School of Food and Biological Engineering and Engineering Research Center of Bioprocess of Ministry of Education, Hefei University of Technology, Hefei, 230009, China
| | - Michael Eisenstein
- Department of Electrical Engineering and Department of Radiology, Stanford University, Stanford, CA 94305, USA
| | - Hyongsok Tom Soh
- Department of Electrical Engineering and Department of Radiology, Stanford University, Stanford, CA 94305, USA
| | - Lei Zheng
- School of Food and Biological Engineering and Engineering Research Center of Bioprocess of Ministry of Education, Hefei University of Technology, Hefei, 230009, China
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4
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Hwang Y, Kim SG, Jang S, Kim J, Jung GY. Signal amplification and optimization of riboswitch-based hybrid inputs by modular and titratable toehold switches. J Biol Eng 2021; 15:11. [PMID: 33741029 PMCID: PMC7977183 DOI: 10.1186/s13036-021-00261-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 03/03/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Synthetic biological circuits are widely utilized to control microbial cell functions. Natural and synthetic riboswitches are attractive sensor modules for use in synthetic biology applications. However, tuning the fold-change of riboswitch circuits is challenging because a deep understanding of the riboswitch mechanism and screening of mutant libraries is generally required. Therefore, novel molecular parts and strategies for straightforward tuning of the fold-change of riboswitch circuits are needed. RESULTS In this study, we devised a toehold switch-based modulator approach that combines a hybrid input construct consisting of a riboswitch and transcriptional repressor and de-novo-designed riboregulators named toehold switches. First, the introduction of a pair of toehold switches and triggers as a downstream signal-processing module to the hybrid input for coenzyme B12 resulted in a functional riboswitch circuit. Next, several optimization strategies that focused on balancing the expression levels of the RNA components greatly improved the fold-change from 260- to 887-fold depending on the promoter and host strain. Further characterizations confirmed low leakiness and high orthogonality of five toehold switch pairs, indicating the broad applicability of this strategy to riboswitch tuning. CONCLUSIONS The toehold switch-based modulator substantially improved the fold-change compared to the previous sensors with only the hybrid input construct. The programmable RNA-RNA interactions amenable to in silico design and optimization can facilitate further development of RNA-based genetic modulators for flexible tuning of riboswitch circuitry and synthetic biosensors.
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Affiliation(s)
- Yunhee Hwang
- Department of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, 37673, South Korea
| | - Seong Gyeong Kim
- Department of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, 37673, South Korea
| | - Sungho Jang
- Department of Bioengineering and Nano-Bioengineering, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon, 22012, South Korea
- Division of Bioengineering, College of Life Sciences and Bioengineering, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon, 22012, South Korea
| | - Jongmin Kim
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, 37673, South Korea.
| | - Gyoo Yeol Jung
- Department of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, 37673, South Korea.
- School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk, 37673, South Korea.
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5
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Guo M, Huang K, Xu W. Third Generation Whole-Cell Sensing Systems: Synthetic Biology Inside, Nanomaterial Outside. Trends Biotechnol 2020; 39:S0167-7799(20)30262-6. [PMID: 34756379 DOI: 10.1016/j.tibtech.2020.10.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 10/02/2020] [Accepted: 10/02/2020] [Indexed: 01/24/2023]
Abstract
Whole-cell sensing systems (WCSSs) are highly anticipated in the field of on-site detection. However, due to their low specificity, poor stability, and potential environmental problems, their commercial application is unrealistic. Recently, synthetic biology and nanomaterials have provided potential solutions to these problems, propelling WCSSs into a new generation. Synthetic biology provides a complete solution for the intelligent design and assembly of elements, modules, and genetic circuits. Nanomaterials covering the exterior of the cells provide stable protection, remote control capability, and catalytic ability for the WCSSs, and they can limit the horizontal transfer of genetic elements. These advancements enable personalized customization, intelligent control, and self-destruction in the next generation of cell sensors, promoting their industrialization.
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Affiliation(s)
- Mingzhang Guo
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing 100083, China
| | - Kunlun Huang
- Key Laboratory of Safety Assessment of Genetically Modified Organism (Food Safety) (MOA), College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
| | - Wentao Xu
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing 100083, China; Key Laboratory of Safety Assessment of Genetically Modified Organism (Food Safety) (MOA), College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China.
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6
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Bhagdikar D, Grundy FJ, Henkin TM. Transcriptional and translational S-box riboswitches differ in ligand-binding properties. J Biol Chem 2020; 295:6849-6860. [PMID: 32209653 DOI: 10.1074/jbc.ra120.012853] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 03/20/2020] [Indexed: 01/27/2023] Open
Abstract
There are a number of riboswitches that utilize the same ligand-binding domain to regulate transcription or translation. S-box (SAM-I) riboswitches, including the riboswitch present in the Bacillus subtilis metI gene, which encodes cystathionine γ-synthase, regulate the expression of genes involved in methionine metabolism in response to SAM, primarily at the level of transcriptional attenuation. A rarer class of S-box riboswitches is predicted to regulate translation initiation. Here we identified and characterized a translational S-box riboswitch in the metI gene from Desulfurispirillum indicum The regulatory mechanisms of riboswitches are influenced by the kinetics of ligand interaction. The half-life of the translational D. indicum metI RNA-SAM complex is significantly shorter than that of the transcriptional B. subtilis metI RNA. This finding suggests that, unlike the transcriptional RNA, the translational metI riboswitch can make multiple reversible regulatory decisions. Comparison of both RNAs revealed that the second internal loop of helix P3 in the transcriptional RNA usually contains an A residue, whereas the translational RNA contains a C residue that is conserved in other S-box RNAs that are predicted to regulate translation. Mutational analysis indicated that the presence of an A or C residue correlates with RNA-SAM complex stability. Biochemical analyses indicate that the internal loop sequence critically determines the stability of the RNA-SAM complex by influencing the flexibility of residues involved in SAM binding and thereby affects the molecular mechanism of riboswitch function.
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Affiliation(s)
- Divyaa Bhagdikar
- Department of Microbiology and Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210
| | - Frank J Grundy
- Department of Microbiology and Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210
| | - Tina M Henkin
- Department of Microbiology and Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210
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7
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Reprogramming bacteria with RNA regulators. Biochem Soc Trans 2019; 47:1279-1289. [DOI: 10.1042/bst20190173] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 09/13/2019] [Accepted: 09/16/2019] [Indexed: 12/20/2022]
Abstract
Abstract
The revolution of genomics and growth of systems biology urged the creation of synthetic biology, an engineering discipline aiming at recreating and reprogramming cellular functions for industrial needs. There has been a huge effort in synthetic biology to develop versatile and programmable genetic regulators that would enable the precise control of gene expression. Synthetic RNA components have emerged as a solution, offering a diverse range of programmable functions, including signal sensing, gene regulation and the modulation of molecular interactions. Owing to their compactness, structure and way of action, several types of RNA devices that act on DNA, RNA and protein have been characterized and applied in synthetic biology. RNA-based approaches are more ‘economical' for the cell, since they are generally not translated. These RNA-based strategies act on a much shorter time scale than transcription-based ones and can be more efficient than protein-based mechanisms. In this review, we explore these RNA components as building blocks in the RNA synthetic biology field, first by explaining their natural mode of action and secondly discussing how these RNA components have been exploited to rewire bacterial regulatory circuitry.
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8
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Endoh T, Ohyama T, Sugimoto N. RNA-Capturing Microsphere Particles (R-CAMPs) for Optimization of Functional Aptamers. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2019; 15:e1805062. [PMID: 30773785 DOI: 10.1002/smll.201805062] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 01/23/2019] [Indexed: 06/09/2023]
Abstract
RNA aptamers are useful building blocks for constructing functional nucleic acid-based nanoarchitectures. The abilities of aptamers to recognize specific ligands have also been utilized for various biotechnological applications. Solution conditions, which can differ depending on the application, impact the affinity of the aptamers, and thus it is important to optimize the aptamers for the solution conditions to be employed. To simplify the aptamer optimization process, an efficient method that enables re-selection of an aptamer from a partially randomized library is developed. The process relies on RNA-capturing microsphere particles (R-CAMPs): each particle displays different clones of identical DNA and RNA sequences. Using a fluorescence-activated cell sorter, the R-CAMPs that are linked to functional aptamers are sorted. It is demonstrated that after a single round of reselection, several functional aptamers, including the wild-type, are selected from a library of 16 384 sequences. The selection using R-CAMPs is further performed under the solution containing high concentration of ethylene glycol, suggesting applicability in various conditions to optimize an aptamer for a particular application. As any type of RNA clone can be displayed on the microspheres, the technology demonstrated here will be useful for the selection of RNAs based on diverse functions.
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Affiliation(s)
- Tamaki Endoh
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20, Minatojima-minamimachi, Chuo-ku, Kobe, 650-0047, Japan
| | - Tatsuya Ohyama
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20, Minatojima-minamimachi, Chuo-ku, Kobe, 650-0047, Japan
| | - Naoki Sugimoto
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20, Minatojima-minamimachi, Chuo-ku, Kobe, 650-0047, Japan
- Graduate School of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, 7-1-20, Minatojima-minamimachi, Chuo-ku, Kobe, 650-0047, Japan
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9
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Design and optimization of genetically encoded biosensors for high-throughput screening of chemicals. Curr Opin Biotechnol 2018; 54:18-25. [DOI: 10.1016/j.copbio.2018.01.011] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 01/08/2018] [Accepted: 01/11/2018] [Indexed: 02/07/2023]
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10
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Sinumvayo JP, Zhao C, Tuyishime P. Recent advances and future trends of riboswitches: attractive regulatory tools. World J Microbiol Biotechnol 2018; 34:171. [PMID: 30413889 DOI: 10.1007/s11274-018-2554-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Accepted: 11/02/2018] [Indexed: 01/06/2023]
Abstract
Bacterial genomes contain a huge amount of different genes. These genes are spatiotemporally expressed to accomplish some required functions within the organism. Inside the cell, any step of gene expression may be modulated at four possible places such as transcription initiation, translation regulation, mRNA stability and protein stability. To achieve this, there is a necessity of strong regulators either natural or synthetic which can fine-tune gene expression regarding the required function. In recent years, riboswitches as metabolite responsive control elements residing in the untranslated regions of certain messenger RNAs, have been known to control gene expression at transcription or translation level. Importantly, these control elements do not prescribe the involvement of protein factors for metabolite binding. However, they own their particular properties to sense intramolecular metabolites (ligands). Herein, we highlighted current important bacterial riboswitches, their applications to support genetic control, ligand-binding domain mechanisms and current progress in synthetic riboswitches.
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Affiliation(s)
- Jean Paul Sinumvayo
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China. .,University of Chinese Academy of Sciences, Beijing, China.
| | - Chunhua Zhao
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Philibert Tuyishime
- University of Chinese Academy of Sciences, Beijing, China.,Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
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11
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Jang S, Jang S, Noh MH, Lim HG, Jung GY. Novel Hybrid Input Part Using Riboswitch and Transcriptional Repressor for Signal Inverting Amplifier. ACS Synth Biol 2018; 7:2199-2204. [PMID: 30092633 DOI: 10.1021/acssynbio.8b00213] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Genetic circuits are composed of input, logic, and output parts. Construction of complex circuits for practical applications requires numerous tunable genetic parts. However, the limited diversity and complicated tuning methods used for the input parts hinders the scalability of genetic circuits. Therefore, a new type of input part is required that responds to diverse signals and enables easy tuning. Here, we developed RNA-protein hybrid input parts that combine a riboswitch and orthogonal transcriptional repressors. The hybrid inputs successfully regulated the transcription of an output in response to the input signal detected by the riboswitch and resulted in signal inversion because of the expression of transcriptional repressors. Dose-response parameters including fold-change and half-maximal effective concentration were easily modulated and amplified simply by changing the promoter strength. Furthermore, the hybrid input detected both exogenous and endogenous signals, indicating potential applications in metabolite sensing. This hybrid input part could be highly extensible considering the rich variety of components.
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Affiliation(s)
- Sungyeon Jang
- Department of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 37673, Korea
| | - Sungho Jang
- Department of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 37673, Korea
| | - Myung Hyun Noh
- Department of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 37673, Korea
| | - Hyun Gyu Lim
- Department of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 37673, Korea
| | - Gyoo Yeol Jung
- Department of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 37673, Korea
- School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, 77 Cheongam-Ro, Nam-Gu, Pohang, Gyeongbuk 37673, Korea
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12
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Liu D, Mannan AA, Han Y, Oyarzún DA, Zhang F. Dynamic metabolic control: towards precision engineering of metabolism. ACTA ACUST UNITED AC 2018; 45:535-543. [DOI: 10.1007/s10295-018-2013-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 01/13/2018] [Indexed: 12/20/2022]
Abstract
Abstract
Advances in metabolic engineering have led to the synthesis of a wide variety of valuable chemicals in microorganisms. The key to commercializing these processes is the improvement of titer, productivity, yield, and robustness. Traditional approaches to enhancing production use the “push–pull-block” strategy that modulates enzyme expression under static control. However, strains are often optimized for specific laboratory set-up and are sensitive to environmental fluctuations. Exposure to sub-optimal growth conditions during large-scale fermentation often reduces their production capacity. Moreover, static control of engineered pathways may imbalance cofactors or cause the accumulation of toxic intermediates, which imposes burden on the host and results in decreased production. To overcome these problems, the last decade has witnessed the emergence of a new technology that uses synthetic regulation to control heterologous pathways dynamically, in ways akin to regulatory networks found in nature. Here, we review natural metabolic control strategies and recent developments in how they inspire the engineering of dynamically regulated pathways. We further discuss the challenges of designing and engineering dynamic control and highlight how model-based design can provide a powerful formalism to engineer dynamic control circuits, which together with the tools of synthetic biology, can work to enhance microbial production.
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Affiliation(s)
- Di Liu
- 0000 0001 2355 7002 grid.4367.6 Department of Energy, Environmental and Chemical Engineering Washington University in St. Louis 63130 St. Louis MO USA
| | - Ahmad A Mannan
- 0000 0001 2113 8111 grid.7445.2 Department of Mathematics Imperial College London SW7 2AZ London UK
| | - Yichao Han
- 0000 0001 2355 7002 grid.4367.6 Department of Energy, Environmental and Chemical Engineering Washington University in St. Louis 63130 St. Louis MO USA
| | - Diego A Oyarzún
- 0000 0001 2113 8111 grid.7445.2 Department of Mathematics Imperial College London SW7 2AZ London UK
| | - Fuzhong Zhang
- 0000 0001 2355 7002 grid.4367.6 Department of Energy, Environmental and Chemical Engineering Washington University in St. Louis 63130 St. Louis MO USA
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13
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Rode AB, Endoh T, Sugimoto N. Crowding Shifts the FMN Recognition Mechanism of Riboswitch Aptamer from Conformational Selection to Induced Fit. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201803052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ambadas B. Rode
- Frontier Institute for Biomolecular Engineering Research (FIBER); Japan
| | - Tamaki Endoh
- Frontier Institute for Biomolecular Engineering Research (FIBER); Japan
| | - Naoki Sugimoto
- Frontier Institute for Biomolecular Engineering Research (FIBER); Japan
- Graduate School of Frontiers of Innovative Research in Science and Technology (FIRST); Konan University; 7-1-20 Minatojima-minamimachi Chuo-ku Kobe 650-0047 Japan
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14
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Rode AB, Endoh T, Sugimoto N. Crowding Shifts the FMN Recognition Mechanism of Riboswitch Aptamer from Conformational Selection to Induced Fit. Angew Chem Int Ed Engl 2018; 57:6868-6872. [PMID: 29663603 DOI: 10.1002/anie.201803052] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 04/06/2018] [Indexed: 11/07/2022]
Abstract
In bacteria, the binding between the riboswitch aptamer domain and ligand is regulated by environmental cues, such as low Mg2+ in macrophages during pathogenesis to ensure spatiotemporal expression of virulence genes. Binding was investigated between the flavin mononucleotide (FMN) riboswitch aptamer and its anionic ligand in the presence of molecular crowding agent without Mg2+ ion, which mimics pathogenic conditions. Structural, kinetic, and thermodynamic analyses under the crowding revealed more dynamic conformational rearrangements of the FMN riboswitch aptamer compared to dilute Mg2+ -containing solution. It is hypothesized that under crowding conditions FMN binds through an induced fit mechanism in contrast to the conformational selection mechanism previously demonstrated in dilute Mg2+ solution. Since these two mechanisms involve different conformational intermediates and rate constants, these findings have practical significance in areas such as drug design and RNA engineering.
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Affiliation(s)
- Ambadas B Rode
- Frontier Institute for Biomolecular Engineering Research (FIBER), Japan
| | - Tamaki Endoh
- Frontier Institute for Biomolecular Engineering Research (FIBER), Japan
| | - Naoki Sugimoto
- Frontier Institute for Biomolecular Engineering Research (FIBER), Japan.,Graduate School of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe, 650-0047, Japan
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15
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Rizvi NF, Howe JA, Nahvi A, Klein DJ, Fischmann TO, Kim HY, McCoy MA, Walker SS, Hruza A, Richards MP, Chamberlin C, Saradjian P, Butko MT, Mercado G, Burchard J, Strickland C, Dandliker PJ, Smith GF, Nickbarg EB. Discovery of Selective RNA-Binding Small Molecules by Affinity-Selection Mass Spectrometry. ACS Chem Biol 2018; 13:820-831. [PMID: 29412640 DOI: 10.1021/acschembio.7b01013] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Recent advances in understanding the relevance of noncoding RNA (ncRNA) to disease have increased interest in drugging ncRNA with small molecules. The recent discovery of ribocil, a structurally distinct synthetic mimic of the natural ligand of the flavin mononucleotide (FMN) riboswitch, has revealed the potential chemical diversity of small molecules that target ncRNA. Affinity-selection mass spectrometry (AS-MS) is theoretically applicable to high-throughput screening (HTS) of small molecules binding to ncRNA. Here, we report the first application of the Automated Ligand Detection System (ALIS), an indirect AS-MS technique, for the selective detection of small molecule-ncRNA interactions, high-throughput screening against large unbiased small-molecule libraries, and identification and characterization of novel compounds (structurally distinct from both FMN and ribocil) that target the FMN riboswitch. Crystal structures reveal that different compounds induce various conformations of the FMN riboswitch, leading to different activity profiles. Our findings validate the ALIS platform for HTS screening for RNA-binding small molecules and further demonstrate that ncRNA can be broadly targeted by chemically diverse yet selective small molecules as therapeutics.
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Affiliation(s)
- Noreen F. Rizvi
- Merck & Co., Inc., Boston, Massachusetts 02115, United States
| | - John A. Howe
- Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Ali Nahvi
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | - Daniel J. Klein
- Merck & Co., Inc., West Point, Pennsylvania 19486, United States
| | | | - Hai-Young Kim
- Merck & Co., Inc., Boston, Massachusetts 02115, United States
| | - Mark A. McCoy
- Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Scott S. Walker
- Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Alan Hruza
- Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | | | - Chad Chamberlin
- Merck & Co., Inc., Boston, Massachusetts 02115, United States
| | - Peter Saradjian
- Merck & Co., Inc., Boston, Massachusetts 02115, United States
| | | | - Gabriel Mercado
- Biodesy, Inc., South San Francisco, California 94080, United States
| | - Julja Burchard
- Merck & Co., Inc., Boston, Massachusetts 02115, United States
| | | | | | - Graham F. Smith
- Merck & Co., Inc., Boston, Massachusetts 02115, United States
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16
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Jang S, Jang S, Xiu Y, Kang TJ, Lee SH, Koffas MAG, Jung GY. Development of Artificial Riboswitches for Monitoring of Naringenin In Vivo. ACS Synth Biol 2017; 6:2077-2085. [PMID: 28749656 DOI: 10.1021/acssynbio.7b00128] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Microbial strains are considered promising hosts for production of flavonoids because of their rapid growth rate and suitability for large-scale manufacturing. However, productivity and titer of current recombinant strains still do not meet the requirements of industrial processes. Genetically encoded biosensors have been applied for high-throughput screening or dynamic regulation of biosynthetic pathways for enhancing the performance of microbial strains that produce valuable chemicals. Currently, few protein sensor-regulators for flavonoids exist. Unlike the protein-based trans-regulating controllers, riboswitches can respond to their ligands faster and eliminate off-target effects. Here, we developed artificial riboswitches that activate gene expression in response to naringenin, an important flavonoid. RNA aptamers for naringenin were developed using SELEX and cloned upstream of a dual selectable marker gene to construct a riboswitch library. Two in vivo selection routes were applied separately to the library by supplementing naringenin at two different concentrations during enrichments to modulate the operational ranges of the riboswitches. The selected riboswitches were responsive to naringenin and activated gene expression up to 2.91-fold. Operational ranges of the riboswitches were distinguished on the basis of their selection route. Additionally, the specificity of the riboswitches was assessed, and their applicability as dynamic regulators was confirmed. Collectively, the naringenin riboswitches reported in this work will be valuable tools in metabolic engineering of microorganisms for the production of flavonoids.
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Affiliation(s)
- Sungho Jang
- Department
of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Korea
| | - Sungyeon Jang
- Department
of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Korea
| | - Yu Xiu
- Department
of Chemical and Biological Engineering, Center for Biotechnology and
Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
- State
Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, China
- Beijing
Key Laboratory of Bioactive Substances and Functional Food, Beijing Union University, Beijing 100191, China
| | - Taek Jin Kang
- Department
of Chemical and Biochemical Engineering, Dongguk University, 30 Pildong-ro 1-gil, Jung-gu, Seoul, 04620, Korea
| | - Sang-Hyeup Lee
- Department
of Life Chemistry, Catholic University of Daegu, Hayang-ro 13-13,
Hayang-eup, Gyeongsan, Gyeongbuk 38430, Korea
| | - Mattheos A. G. Koffas
- Department
of Chemical and Biological Engineering, Center for Biotechnology and
Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
- Department
of Biological Sciences, Center for Biotechnology and Interdisciplinary
Studies, Rensselaer Polytechnic Institutee, Troy, New York 12180, United States
| | - Gyoo Yeol Jung
- Department
of Chemical Engineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Korea
- School
of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, 77 Cheongam-ro, Nam-gu, Pohang, Gyeongbuk 37673, Korea
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17
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Jang S, Jung GY. Systematic optimization of L-tryptophan riboswitches for efficient monitoring of the metabolite in Escherichia coli. Biotechnol Bioeng 2017; 115:266-271. [PMID: 28892124 DOI: 10.1002/bit.26448] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 08/11/2017] [Accepted: 09/08/2017] [Indexed: 12/31/2022]
Abstract
Riboswitches form a class of genetically encoded sensor-regulators and are considered as promising tools for monitoring various metabolites. Functional parameters of a riboswitch, like dynamic or operational range, should be optimized before the riboswitch is implemented in a specific application for monitoring the target molecule efficiently. However, optimization of a riboswitch was not straightforward and required detailed studies owing to its complex sequence-function relationship. Here, we present three approaches for tuning and optimization of functional parameters of a riboswitch using an artificial L-tryptophan riboswitch as an example. First, the constitutive expression level was adjusted to control the dynamic range of an L-tryptophan riboswitch. The dynamic range increased as the constitutive expression level increased. Then, the function of a riboswitch-encoded protein was utilized to connect the regulatory response of the riboswitch to another outcome for amplifying the dynamic range. Riboswitch-mediated control of the host cell growth enabled the amplification of the riboswitch response. Finally, L-tryptophan aptamers with different dissociation constants were employed to alter the operational range of the riboswitch. The dose-response curve was shifted towards higher L-tryptophan concentrations when an aptamer with higher dissociation constant was employed. All strategies were effective in modifying the distinct functional parameters of the L-tryptophan riboswitch, and they could be easily applied to optimization of other riboswitches owing to their simplicity.
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Affiliation(s)
- Sungho Jang
- Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, Gyeongbuk, Korea
| | - Gyoo Yeol Jung
- Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, Gyeongbuk, Korea.,School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang, Gyeongbuk, Korea
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18
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Domin G, Findeiß S, Wachsmuth M, Will S, Stadler PF, Mörl M. Applicability of a computational design approach for synthetic riboswitches. Nucleic Acids Res 2017; 45:4108-4119. [PMID: 27994029 PMCID: PMC5397205 DOI: 10.1093/nar/gkw1267] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 12/06/2016] [Indexed: 02/07/2023] Open
Abstract
Riboswitches have gained attention as tools for synthetic biology, since they enable researchers to reprogram cells to sense and respond to exogenous molecules. In vitro evolutionary approaches produced numerous RNA aptamers that bind such small ligands, but their conversion into functional riboswitches remains difficult. We previously developed a computational approach for the design of synthetic theophylline riboswitches based on secondary structure prediction. These riboswitches have been constructed to regulate ligand-dependent transcription termination in Escherichia coli. Here, we test the usability of this design strategy by applying the approach to tetracycline and streptomycin aptamers. The resulting tetracycline riboswitches exhibit robust regulatory properties in vivo. Tandem fusions of these riboswitches with theophylline riboswitches represent logic gates responding to two different input signals. In contrast, the conversion of the streptomycin aptamer into functional riboswitches appears to be difficult. Investigations of the underlying aptamer secondary structure revealed differences between in silico prediction and structure probing. We conclude that only aptamers adopting the minimal free energy (MFE) structure are suitable targets for construction of synthetic riboswitches with design approaches based on equilibrium thermodynamics of RNA structures. Further improvements in the design strategy are required to implement aptamer structures not corresponding to the calculated MFE state.
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Affiliation(s)
- Gesine Domin
- Leipzig University, Institute for Biochemistry, 04103 Leipzig, Germany
| | - Sven Findeiß
- University of Vienna, Research Group Bioinformatics and Computational Biology, Faculty of Computer Science, A-1090 Vienna, Austria.,University of Vienna, Institute for Theoretical Chemistry, A-1090 Vienna, Austria
| | - Manja Wachsmuth
- Leipzig University, Institute for Biochemistry, 04103 Leipzig, Germany
| | - Sebastian Will
- Leipzig University, Bioinformatics Group, Department of Computer Science and Interdisciplinary Center for Bioinformatics, 04107 Leipzig, Germany
| | - Peter F Stadler
- University of Vienna, Institute for Theoretical Chemistry, A-1090 Vienna, Austria.,Leipzig University, Bioinformatics Group, Department of Computer Science and Interdisciplinary Center for Bioinformatics, 04107 Leipzig, Germany.,Max Planck Institute for Mathematics in the Science, 04103 Leipzig, Germany.,Fraunhofer Institute for Cell Therapy and Immunology, 04103 Leipzig, Germany.,Santa Fe Institute, Santa Fe NM 87501, USA
| | - Mario Mörl
- Leipzig University, Institute for Biochemistry, 04103 Leipzig, Germany
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19
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Endoh T, Sugimoto N. Conformational Dynamics of mRNA in Gene Expression as New Pharmaceutical Target. CHEM REC 2017; 17:817-832. [DOI: 10.1002/tcr.201700016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Indexed: 11/05/2022]
Affiliation(s)
- Tamaki Endoh
- Frontier Institute for Biomolecular Engineering Research (FIBER); Konan University; 7-1-20 Minatojima-minamimachi Chuo-ku, Kobe 650-0047 Japan
| | - Naoki Sugimoto
- Frontier Institute for Biomolecular Engineering Research (FIBER); Konan University; 7-1-20 Minatojima-minamimachi Chuo-ku, Kobe 650-0047 Japan
- Graduate School of Frontiers of Innovative Research in Science and Technology (FIRST); Konan University; 7-1-20 Minatojima-minamimachi Chuo-ku, Kobe 650-0047 Japan
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20
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Hallberg ZF, Su Y, Kitto RZ, Hammond MC. Engineering and In Vivo Applications of Riboswitches. Annu Rev Biochem 2017; 86:515-539. [PMID: 28375743 DOI: 10.1146/annurev-biochem-060815-014628] [Citation(s) in RCA: 99] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Riboswitches are common gene regulatory units mostly found in bacteria that are capable of altering gene expression in response to a small molecule. These structured RNA elements consist of two modular subunits: an aptamer domain that binds with high specificity and affinity to a target ligand and an expression platform that transduces ligand binding to a gene expression output. Significant progress has been made in engineering novel aptamer domains for new small molecule inducers of gene expression. Modified expression platforms have also been optimized to function when fused with both natural and synthetic aptamer domains. As this field expands, the use of these privileged scaffolds has permitted the development of tools such as RNA-based fluorescent biosensors. In this review, we summarize the methods that have been developed to engineer new riboswitches and highlight applications of natural and synthetic riboswitches in enzyme and strain engineering, in controlling gene expression and cellular physiology, and in real-time imaging of cellular metabolites and signals.
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Affiliation(s)
- Zachary F Hallberg
- Department of Chemistry, University of California, Berkeley, California 94720;
| | - Yichi Su
- Department of Chemistry, University of California, Berkeley, California 94720;
| | - Rebekah Z Kitto
- Department of Chemistry, University of California, Berkeley, California 94720;
| | - Ming C Hammond
- Department of Chemistry, University of California, Berkeley, California 94720; .,Department of Molecular and Cell Biology, University of California, Berkeley, California 94720
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21
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Characterization of Engineered PreQ1 Riboswitches for Inducible Gene Regulation in Mycobacteria. J Bacteriol 2017; 199:JB.00656-16. [PMID: 28069821 DOI: 10.1128/jb.00656-16] [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: 09/07/2016] [Accepted: 01/03/2017] [Indexed: 11/20/2022] Open
Abstract
We report here the behavior of naturally occurring and rationally engineered preQ1 riboswitches and their application to inducible gene regulation in mycobacteria. Because mycobacteria lack preQ1 biosynthetic genes, we hypothesized that preQ1 could be used as an exogenous nonmetabolite ligand to control riboswitches in mycobacteria. Selected naturally occurring preQ1 riboswitches were assayed and successfully drove preQ1-dependent repression of a green fluorescent protein reporter in Mycobacterium smegmatis Using structure-based design, we engineered three preQ1 riboswitches from Thermoanaerobacter tencongensis, Bacillus subtilis, and Lactobacillus rhamnosus toward achieving higher response ratios and increased repression. Assuming a steady-state model, variants of the T. tencongensis riboswitch most closely followed the predicted trends. Unexpectedly, the preQ1 dose response was best described by a model with a second, independent preQ1 binding site. This behavior was general to the preQ1 riboswitch family, since the wild type and rationally designed mutants of riboswitches from all three bacteria behaved analogously. Across all variants, the response ratios, which describe expression in the absence versus the presence of preQ1, ranged from <2 to ∼10, but repression in all cases was incomplete up to 1 mM preQ1. By reducing the transcript expression level, we obtained a preQ1 riboswitch variant appropriate for inducible knockdown applications. We further showed that the preQ1 response is reversible, is titratable, and can be used to control protein expression in mycobacteria within infected macrophages. By engineering naturally occurring preQ1 riboswitches, we have not only extended the tools available for inducible gene regulation in mycobacteria but also uncovered new behavior of these riboswitches.IMPORTANCE Riboswitches are elements found in noncoding regions of mRNA that regulate gene expression, typically in response to an endogenous metabolite. Riboswitches have emerged as important tools for inducible gene expression in diverse organisms. We noted that mycobacteria lack the biosynthesis genes for preQ1, a ligand for riboswitches from diverse bacteria. Predicting that preQ1 is not present in mycobacteria, we showed that it controls optimized riboswitches appropriate for gene knockdown applications. Further, the riboswitch response is subject to a second independent preQ1 binding event that has not been previously documented. By engineering naturally occurring riboswitches, we have uncovered a new behavior, with implications for riboswitch function in its native context, and extended the tools available for inducible gene regulation in mycobacteria.
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22
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Abstract
Riboflavin derivatives are essential cofactors for a myriad of flavoproteins. In bacteria, flavins importance extends beyond their role as intracellular protein cofactors, as secreted flavins are a key metabolite in a variety of physiological processes. Bacteria obtain riboflavin through the endogenous riboflavin biosynthetic pathway (RBP) or by the use of importer proteins. Bacteria frequently encode multiple paralogs of the RBP enzymes and as for other micronutrient supply pathways, biosynthesis and uptake functions largely coexist. It is proposed that bacteria shut down biosynthesis and would rather uptake riboflavin when the vitamin is environmentally available. Recently, the overlap of riboflavin provisioning elements has gained attention and the functions of duplicated paralogs of RBP enzymes started to be addressed. Results point towards the existence of a modular structure in the bacterial riboflavin supply pathways. Such structure uses subsets of RBP genes to supply riboflavin for specific functions. Given the importance of riboflavin in intra and extracellular bacterial physiology, this complex array of riboflavin provision pathways may have developed to contend with the various riboflavin requirements. In riboflavin-prototrophic bacteria, riboflavin transporters could represent a module for riboflavin provision for particular, yet unidentified processes, rather than substituting for the RBP as usually assumed.
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Affiliation(s)
- Víctor Antonio García-Angulo
- a Microbiology and Mycology Program, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile , Santiago , Chile
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23
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Rode AB, Endoh T, Sugimoto N. tRNA Shifts the G-quadruplex-Hairpin Conformational Equilibrium in RNA towards the Hairpin Conformer. Angew Chem Int Ed Engl 2016; 55:14315-14319. [DOI: 10.1002/anie.201605431] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Ambadas B. Rode
- Frontier Institute for Biomolecular Engineering Research (FIBER); Konan University; 7-1-20 Minatojima-minamimachi, Chuo-ku Kobe 650-0047 Japan
| | - Tamaki Endoh
- Frontier Institute for Biomolecular Engineering Research (FIBER); Konan University; 7-1-20 Minatojima-minamimachi, Chuo-ku Kobe 650-0047 Japan
| | - Naoki Sugimoto
- Frontier Institute for Biomolecular Engineering Research (FIBER); Konan University; 7-1-20 Minatojima-minamimachi, Chuo-ku Kobe 650-0047 Japan
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24
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Rode AB, Endoh T, Sugimoto N. tRNA Shifts the G-quadruplex-Hairpin Conformational Equilibrium in RNA towards the Hairpin Conformer. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201605431] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Ambadas B. Rode
- Frontier Institute for Biomolecular Engineering Research (FIBER); Konan University; 7-1-20 Minatojima-minamimachi, Chuo-ku Kobe 650-0047 Japan
| | - Tamaki Endoh
- Frontier Institute for Biomolecular Engineering Research (FIBER); Konan University; 7-1-20 Minatojima-minamimachi, Chuo-ku Kobe 650-0047 Japan
| | - Naoki Sugimoto
- Frontier Institute for Biomolecular Engineering Research (FIBER); Konan University; 7-1-20 Minatojima-minamimachi, Chuo-ku Kobe 650-0047 Japan
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25
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Trends in the Design and Development of Specific Aptamers Against Peptides and Proteins. Protein J 2016; 35:81-99. [DOI: 10.1007/s10930-016-9653-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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26
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ACEMBL Tool-Kits for High-Throughput Multigene Delivery and Expression in Prokaryotic and Eukaryotic Hosts. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 896:27-42. [DOI: 10.1007/978-3-319-27216-0_3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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27
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Howe JA, Wang H, Fischmann TO, Balibar CJ, Xiao L, Galgoci AM, Malinverni JC, Mayhood T, Villafania A, Nahvi A, Murgolo N, Barbieri CM, Mann PA, Carr D, Xia E, Zuck P, Riley D, Painter RE, Walker SS, Sherborne B, de Jesus R, Pan W, Plotkin MA, Wu J, Rindgen D, Cummings J, Garlisi CG, Zhang R, Sheth PR, Gill CJ, Tang H, Roemer T. Selective small-molecule inhibition of an RNA structural element. Nature 2015; 526:672-7. [PMID: 26416753 DOI: 10.1038/nature15542] [Citation(s) in RCA: 279] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 09/04/2015] [Indexed: 02/06/2023]
Abstract
Riboswitches are non-coding RNA structures located in messenger RNAs that bind endogenous ligands, such as a specific metabolite or ion, to regulate gene expression. As such, riboswitches serve as a novel, yet largely unexploited, class of emerging drug targets. Demonstrating this potential, however, has proven difficult and is restricted to structurally similar antimetabolites and semi-synthetic analogues of their cognate ligand, thus greatly restricting the chemical space and selectivity sought for such inhibitors. Here we report the discovery and characterization of ribocil, a highly selective chemical modulator of bacterial riboflavin riboswitches, which was identified in a phenotypic screen and acts as a structurally distinct synthetic mimic of the natural ligand, flavin mononucleotide, to repress riboswitch-mediated ribB gene expression and inhibit bacterial cell growth. Our findings indicate that non-coding RNA structural elements may be more broadly targeted by synthetic small molecules than previously expected.
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Affiliation(s)
- John A Howe
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | - Hao Wang
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | | | - Carl J Balibar
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | - Li Xiao
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | | | | | - Todd Mayhood
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | | | - Ali Nahvi
- Merck Research Laboratories, West Point, Pennsylvania 19486, USA
| | | | | | - Paul A Mann
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | - Donna Carr
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | - Ellen Xia
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | - Paul Zuck
- Merck Research Laboratories, North Wales, Pennsylvania 19454, USA
| | - Dan Riley
- Merck Research Laboratories, North Wales, Pennsylvania 19454, USA
| | | | - Scott S Walker
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | - Brad Sherborne
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | | | - Weidong Pan
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | | | - Jin Wu
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | - Diane Rindgen
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | - John Cummings
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | | | - Rumin Zhang
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | - Payal R Sheth
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | - Charles J Gill
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | - Haifeng Tang
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
| | - Terry Roemer
- Merck Research Laboratories, Kenilworth, New Jersey 07033, USA
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28
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Wostenberg C, Ceres P, Polaski JT, Batey RT. A Highly Coupled Network of Tertiary Interactions in the SAM-I Riboswitch and Their Role in Regulatory Tuning. J Mol Biol 2015; 427:3473-3490. [PMID: 26343759 DOI: 10.1016/j.jmb.2015.07.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2015] [Revised: 07/27/2015] [Accepted: 07/30/2015] [Indexed: 01/24/2023]
Abstract
RNA folding in vivo is significantly influenced by transcription, which is not necessarily recapitulated by Mg(2+)-induced folding of the corresponding full-length RNA in vitro. Riboswitches that regulate gene expression at the transcriptional level are an ideal system for investigating this aspect of RNA folding as ligand-dependent termination is obligatorily co-transcriptional, providing a clear readout of the folding outcome. The folding of representative members of the SAM-I family of riboswitches has been extensively analyzed using approaches focusing almost exclusively upon Mg(2+) and/or S-adenosylmethionine (SAM)-induced folding of full-length transcripts of the ligand binding domain. To relate these findings to co-transcriptional regulatory activity, we have investigated a set of structure-guided mutations of conserved tertiary architectural elements of the ligand binding domain using an in vitro single-turnover transcriptional termination assay, complemented with phylogenetic analysis and isothermal titration calorimetry data. This analysis revealed a conserved internal loop adjacent to the SAM binding site that significantly affects ligand binding and regulatory activity. Conversely, most single point mutations throughout key conserved features in peripheral tertiary architecture supporting the SAM binding pocket have relatively little impact on riboswitch activity. Instead, a secondary structural element in the peripheral subdomain appears to be the key determinant in observed differences in regulatory properties across the SAM-I family. These data reveal a highly coupled network of tertiary interactions that promote high-fidelity co-transcriptional folding of the riboswitch but are only indirectly linked to regulatory tuning.
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Affiliation(s)
- Christopher Wostenberg
- Department of Chemistry and Biochemistry, University of Colorado Boulder, 596 UCB, Boulder, CO 80309-0596, USA
| | - Pablo Ceres
- Department of Chemistry and Biochemistry, University of Colorado Boulder, 596 UCB, Boulder, CO 80309-0596, USA
| | - Jacob T Polaski
- Department of Chemistry and Biochemistry, University of Colorado Boulder, 596 UCB, Boulder, CO 80309-0596, USA
| | - Robert T Batey
- Department of Chemistry and Biochemistry, University of Colorado Boulder, 596 UCB, Boulder, CO 80309-0596, USA.
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29
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Rode AB, Endoh T, Sugimoto N. Key Tertiary Interactions in FMN Riboswitch Aptamers Required for Ligand Binding. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2015. [DOI: 10.1246/bcsj.20150063] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Ambadas B. Rode
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University
| | - Tamaki Endoh
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University
| | - Naoki Sugimoto
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University
- Graduate School of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University
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