1
|
Fontana J, Sparkman-Yager D, Faulkner I, Cardiff R, Kiattisewee C, Walls A, Primo TG, Kinnunen PC, Garcia Martin H, Zalatan JG, Carothers JM. Guide RNA structure design enables combinatorial CRISPRa programs for biosynthetic profiling. Nat Commun 2024; 15:6341. [PMID: 39068154 PMCID: PMC11283517 DOI: 10.1038/s41467-024-50528-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 07/12/2024] [Indexed: 07/30/2024] Open
Abstract
Engineering metabolism to efficiently produce chemicals from multi-step pathways requires optimizing multi-gene expression programs to achieve enzyme balance. CRISPR-Cas transcriptional control systems are emerging as important tools for programming multi-gene expression, but poor predictability of guide RNA folding can disrupt expression control. Here, we correlate efficacy of modified guide RNAs (scRNAs) for CRISPR activation (CRISPRa) in E. coli with a computational kinetic parameter describing scRNA folding rate into the active structure (rS = 0.8). This parameter also enables forward design of scRNAs, allowing us to design a system of three synthetic CRISPRa promoters that can orthogonally activate (>35-fold) expression of chosen outputs. Through combinatorial activation tuning, we profile a three-dimensional design space expressing two different biosynthetic pathways, demonstrating variable production of pteridine and human milk oligosaccharide products. This RNA design approach aids combinatorial optimization of metabolic pathways and may accelerate routine design of effective multi-gene regulation programs in bacterial hosts.
Collapse
Affiliation(s)
- Jason Fontana
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, WA, USA
- Department of Chemistry, University of Washington, Seattle, WA, USA
- Department of Chemical Engineering, University of Washington, Seattle, WA, USA
| | - David Sparkman-Yager
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, WA, USA
- Department of Chemical Engineering, University of Washington, Seattle, WA, USA
| | - Ian Faulkner
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, WA, USA
- Department of Chemical Engineering, University of Washington, Seattle, WA, USA
| | - Ryan Cardiff
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, WA, USA
- Department of Chemistry, University of Washington, Seattle, WA, USA
- Department of Chemical Engineering, University of Washington, Seattle, WA, USA
| | - Cholpisit Kiattisewee
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, WA, USA
- Department of Chemistry, University of Washington, Seattle, WA, USA
- Department of Chemical Engineering, University of Washington, Seattle, WA, USA
| | - Aria Walls
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, WA, USA
- Department of Chemical Engineering, University of Washington, Seattle, WA, USA
| | - Tommy G Primo
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, WA, USA
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Patrick C Kinnunen
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Biofuels and Bioproducts Division, DOE Joint BioEnergy Institute, Emeryville, CA, USA
- DOE Agile BioFoundry, Emeryville, CA, USA
| | - Hector Garcia Martin
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Biofuels and Bioproducts Division, DOE Joint BioEnergy Institute, Emeryville, CA, USA
- DOE Agile BioFoundry, Emeryville, CA, USA
| | - Jesse G Zalatan
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, WA, USA.
- Department of Chemistry, University of Washington, Seattle, WA, USA.
| | - James M Carothers
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, WA, USA.
- Department of Chemical Engineering, University of Washington, Seattle, WA, USA.
| |
Collapse
|
2
|
Stukenberg D, Faber A, Becker A. Graded-CRISPRi, a Tool for Tuning the Strengths of CRISPRi-Mediated Knockdowns in Vibrio natriegens Using gRNA Libraries. ACS Synth Biol 2024; 13:2091-2104. [PMID: 38916455 DOI: 10.1021/acssynbio.4c00056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
In recent years, the fast-growing bacterium Vibrio natriegens has gained increasing attention as it has the potential to become a next-generation chassis for synthetic biology. A wide range of genetic parts and genome engineering methods have already been developed. However, there is still a need for a well-characterized tool to effectively and gradually reduce the expression levels of native genes. To bridge this gap, we created graded-CRISPRi, a system utilizing gRNA variants that lead to varying levels of repression strength. By incorporating multiple gRNA sequences into our design, we successfully extended this concept to simultaneously repress four distinct reporter genes. Furthermore, we demonstrated the capability of using graded-CRISPRi to target native genes, thereby examining the effect of various knockdown levels on growth.
Collapse
Affiliation(s)
- Daniel Stukenberg
- Center for Synthetic Microbiology, Philipps-Universität Marburg, Marburg 35037, Germany
- Department of Biology, Philipps-Universität Marburg, Marburg 35037, Germany
| | - Anna Faber
- Center for Synthetic Microbiology, Philipps-Universität Marburg, Marburg 35037, Germany
- Department of Biology, Philipps-Universität Marburg, Marburg 35037, Germany
| | - Anke Becker
- Center for Synthetic Microbiology, Philipps-Universität Marburg, Marburg 35037, Germany
- Department of Biology, Philipps-Universität Marburg, Marburg 35037, Germany
| |
Collapse
|
3
|
Burbano DA, Kiattisewee C, Karanjia AV, Cardiff RAL, Faulkner ID, Sugianto W, Carothers JM. CRISPR Tools for Engineering Prokaryotic Systems: Recent Advances and New Applications. Annu Rev Chem Biomol Eng 2024; 15:389-430. [PMID: 38598861 DOI: 10.1146/annurev-chembioeng-100522-114706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2024]
Abstract
In the past decades, the broad selection of CRISPR-Cas systems has revolutionized biotechnology by enabling multimodal genetic manipulation in diverse organisms. Rooted in a molecular engineering perspective, we recapitulate the different CRISPR components and how they can be designed for specific genetic engineering applications. We first introduce the repertoire of Cas proteins and tethered effectors used to program new biological functions through gene editing and gene regulation. We review current guide RNA (gRNA) design strategies and computational tools and how CRISPR-based genetic circuits can be constructed through regulated gRNA expression. Then, we present recent advances in CRISPR-based biosensing, bioproduction, and biotherapeutics across in vitro and in vivo prokaryotic systems. Finally, we discuss forthcoming applications in prokaryotic CRISPR technology that will transform synthetic biology principles in the near future.
Collapse
Affiliation(s)
- Diego Alba Burbano
- Department of Chemical Engineering, University of Washington, Seattle, Washington, USA
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, Washington, USA;
| | - Cholpisit Kiattisewee
- Department of Chemical Engineering, University of Washington, Seattle, Washington, USA
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, Washington, USA;
| | - Ava V Karanjia
- Department of Chemical Engineering, University of Washington, Seattle, Washington, USA
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, Washington, USA;
| | - Ryan A L Cardiff
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, Washington, USA;
| | - Ian D Faulkner
- Department of Chemical Engineering, University of Washington, Seattle, Washington, USA
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, Washington, USA;
| | - Widianti Sugianto
- Department of Chemical Engineering, University of Washington, Seattle, Washington, USA
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, Washington, USA;
| | - James M Carothers
- Department of Chemical Engineering, University of Washington, Seattle, Washington, USA
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, Washington, USA;
| |
Collapse
|
4
|
Kim G, Kim HJ, Kim K, Kim HJ, Yang J, Seo SW. Tunable translation-level CRISPR interference by dCas13 and engineered gRNA in bacteria. Nat Commun 2024; 15:5319. [PMID: 38909033 PMCID: PMC11193725 DOI: 10.1038/s41467-024-49642-x] [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: 11/15/2023] [Accepted: 06/13/2024] [Indexed: 06/24/2024] Open
Abstract
Although CRISPR-dCas13, the RNA-guided RNA-binding protein, was recently exploited as a translation-level gene expression modulator, it has still been difficult to precisely control the level due to the lack of detailed characterization. Here, we develop a synthetic tunable translation-level CRISPR interference (Tl-CRISPRi) system based on the engineered guide RNAs that enable precise and predictable down-regulation of mRNA translation. First, we optimize the Tl-CRISPRi system for specific and multiplexed repression of genes at the translation level. We also show that the Tl-CRISPRi system is more suitable for independently regulating each gene in a polycistronic operon than the transcription-level CRISPRi (Tx-CRISPRi) system. We further engineer the handle structure of guide RNA for tunable and predictable repression of various genes in Escherichia coli and Vibrio natriegens. This tunable Tl-CRISPRi system is applied to increase the production of 3-hydroxypropionic acid (3-HP) by 14.2-fold via redirecting the metabolic flux, indicating the usefulness of this system for the flux optimization in the microbial cell factories based on the RNA-targeting machinery.
Collapse
Affiliation(s)
- Giho Kim
- School of Chemical and Biological Engineering, Seoul National University, Seoul, Republic of Korea
| | - Ho Joon Kim
- School of Chemical and Biological Engineering, Seoul National University, Seoul, Republic of Korea
| | - Keonwoo Kim
- School of Chemical and Biological Engineering, Seoul National University, Seoul, Republic of Korea
| | - Hyeon Jin Kim
- Interdisciplinary Program in Bioengineering, Seoul National University, Seoul, South Korea
| | - Jina Yang
- Department of Chemical Engineering, Jeju National University, Jeju-si, South Korea
| | - Sang Woo Seo
- School of Chemical and Biological Engineering, Seoul National University, Seoul, Republic of Korea.
- Interdisciplinary Program in Bioengineering, Seoul National University, Seoul, South Korea.
- Institute of Chemical Processes, Seoul National University, Seoul, South Korea.
- Bio-MAX Institute, Seoul National University, Seoul, South Korea.
- Institute of Bio Engineering, Seoul National University, Seoul, South Korea.
| |
Collapse
|
5
|
Tang M, Xu X, Liu Y, Li J, Du G, Lv X, Liu L. Combinatorial Metabolic Engineering for Improving Betulinic Acid Biosynthesis in Saccharomyces cerevisiae. ACS Synth Biol 2024; 13:1798-1808. [PMID: 38748665 DOI: 10.1021/acssynbio.4c00104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/22/2024]
Abstract
Betulinic acid (BA) is a lupane-type triterpenoid with potent anticancer and anti-HIV activities. Its great potential in clinical applications necessitates the development of an efficient strategy for BA synthesis. This study attempted to achieve efficient BA biosynthesis in Saccharomyces cerevisiae using systematic metabolic engineering strategies. First, a de novo BA biosynthesis pathway in S. cerevisiae was constructed, which yielded a titer of 14.01 ± 0.21 mg/L. Then, by enhancing the BA synthesis pathway and dynamic inhibition of the competitive pathway, a greater proportion of the metabolic flow was directed toward BA synthesis, achieving a titer of 88.07 ± 5.83 mg/L. Next, acetyl-CoA and NADPH supply was enhanced, which increased the BA titer to 166.43 ± 1.83 mg/L. Finally, another BA synthesis pathway in the peroxisome was constructed. Dual regulation of the peroxisome and cytoplasmic metabolism increased the BA titer to 210.88 ± 4.76 mg/L. Following fed-batch fermentation process modification, the BA titer reached 682.29 ± 8.16 mg/L. Overall, this work offers a guide for building microbial cell factories that are capable of producing terpenoids with efficiency.
Collapse
Affiliation(s)
- Mei Tang
- 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
| | - 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
| | - 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
| | - 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
- Institute of Future Food and Technology, JITRI, Yixing 214200, China
| |
Collapse
|
6
|
Gawlitt S, Collins SP, Yu Y, Blackman SA, Barquist L, Beisel CL. Expanding the flexibility of base editing for high-throughput genetic screens in bacteria. Nucleic Acids Res 2024; 52:4079-4097. [PMID: 38499498 DOI: 10.1093/nar/gkae174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 02/07/2024] [Accepted: 02/28/2024] [Indexed: 03/20/2024] Open
Abstract
Genome-wide screens have become powerful tools for elucidating genotype-to-phenotype relationships in bacteria. Of the varying techniques to achieve knockout and knockdown, CRISPR base editors are emerging as promising options. However, the limited number of available, efficient target sites hampers their use for high-throughput screening. Here, we make multiple advances to enable flexible base editing as part of high-throughput genetic screening in bacteria. We first co-opt the Streptococcus canis Cas9 that exhibits more flexible protospacer-adjacent motif recognition than the traditional Streptococcus pyogenes Cas9. We then expand beyond introducing premature stop codons by mutating start codons. Next, we derive guide design rules by applying machine learning to an essentiality screen conducted in Escherichia coli. Finally, we rescue poorly edited sites by combining base editing with Cas9-induced cleavage of unedited cells, thereby enriching for intended edits. The efficiency of this dual system was validated through a conditional essentiality screen based on growth in minimal media. Overall, expanding the scope of genome-wide knockout screens with base editors could further facilitate the investigation of new gene functions and interactions in bacteria.
Collapse
Affiliation(s)
- Sandra Gawlitt
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), 97080 Würzburg, Germany
| | - Scott P Collins
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, USA
| | - Yanying Yu
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), 97080 Würzburg, Germany
| | - Samuel A Blackman
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, USA
| | - Lars Barquist
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), 97080 Würzburg, Germany
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario L5L 1C6, Canada
- Medical Faculty, University of Würzburg, 97080 Würzburg, Germany
| | - Chase L Beisel
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), 97080 Würzburg, Germany
- Medical Faculty, University of Würzburg, 97080 Würzburg, Germany
| |
Collapse
|
7
|
Laster DJ, Akel NS, Hendrixson JA, James A, Crawford JA, Fu Q, Berryhill SB, Thostenson JD, Nookaew I, O’Brien CA, Onal M. CRISPR interference provides increased cell type-specificity compared to the Cre-loxP system. iScience 2023; 26:107428. [PMID: 37575184 PMCID: PMC10415806 DOI: 10.1016/j.isci.2023.107428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 06/12/2023] [Accepted: 07/17/2023] [Indexed: 08/15/2023] Open
Abstract
Cre-mediated recombination is frequently used for cell type-specific loss of function (LOF) studies. A major limitation of this system is recombination in unwanted cell types. CRISPR interference (CRISPRi) has been used effectively for global LOF in mice. However, cell type-specific CRISPRi, independent of recombination-based systems, has not been reported. To test the feasibility of cell type-specific CRISPRi, we produced two novel knock-in mouse models that achieve gene suppression when used together: one expressing dCas9::KRAB under the control of a cell type-specific promoter and the other expressing a single guide RNA from a safe harbor locus. We then compared the phenotypes of mice in which the same gene was targeted by either CRISPRi or the Cre-loxP system, with cell specificity conferred by Dmp1 regulatory elements in both cases. We demonstrate that CRISPRi is effective for cell type-specific LOF and that it provides improved cell type-specificity compared to the Cre-loxP system.
Collapse
Affiliation(s)
- Dominique J. Laster
- Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Nisreen S. Akel
- Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - James A. Hendrixson
- Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Alicen James
- Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Julie A. Crawford
- Center for Musculoskeletal Disease Research (CMDR), University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
- Division of Endocrinology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Qiang Fu
- Center for Musculoskeletal Disease Research (CMDR), University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
- Division of Endocrinology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Stuart B. Berryhill
- Center for Musculoskeletal Disease Research (CMDR), University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
- Division of Endocrinology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Jeff D. Thostenson
- Department of Biostatistics, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Intawat Nookaew
- Center for Musculoskeletal Disease Research (CMDR), University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
- Department of Biomedical Informatics, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Charles A. O’Brien
- Center for Musculoskeletal Disease Research (CMDR), University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
- Division of Endocrinology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Melda Onal
- Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
- Center for Musculoskeletal Disease Research (CMDR), University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| |
Collapse
|
8
|
Yang Y, Wang D, Lü P, Ma S, Chen K. Research progress on nucleic acid detection and genome editing of CRISPR/Cas12 system. Mol Biol Rep 2023; 50:3723-3738. [PMID: 36648696 PMCID: PMC9843688 DOI: 10.1007/s11033-023-08240-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 01/03/2023] [Indexed: 01/18/2023]
Abstract
PURPOSE This work characterizes the applications of CRISPR/Cas12 system, including nucleic acid detection, animal, plant and microbial genome editing. METHODS The literature on CRISPR/Cas12 system was collected and reviewed. RESULTS CRISPR/Cas system is an acquired immune system derived from bacteria and archaea, which has become the most popular technology around the world because of its outstanding contribution in genome editing. Type V CRISPR/Cas systems are distinguished by a single RNA-guided RuvC nuclease domain with single effector molecule. Cas12a, the first reported type V CRISPR/Cas system, targets double-stranded DNA (dsDNA) adjacent to PAM sequences and trans-cleaves single-stranded DNA (ssDNA). We present the applications of CRISPR/Cas12 system for nucleic acid detection and genome editing in animals, plants and microorganisms. Furthermore, this review also summarizes the applications of other Cas12 proteins, such as Cas12b, Cas12c, Cas12d, and so on, which further widen the application prospects of CRISPR/Cas12 system. CONCLUSIONS Knowledge of the applications of CRISPR/Cas12 system is necessary for improving the understanding of the functional diversity of CRISPR/Cas12 system and also provides significant references for further research and utilization of CRISPR/Cas12 in other new fields.
Collapse
Affiliation(s)
- Yanhua Yang
- School of Life Sciences, Jiangsu University, 301 Xuefu Road, Zhenjiang, 212013, Jiangsu Province, People's Republic of China.
| | - Dandan Wang
- School of Life Sciences, Jiangsu University, 301 Xuefu Road, Zhenjiang, 212013, Jiangsu Province, People's Republic of China
| | - Peng Lü
- School of Life Sciences, Jiangsu University, 301 Xuefu Road, Zhenjiang, 212013, Jiangsu Province, People's Republic of China
| | - Shangshang Ma
- School of Life Sciences, Jiangsu University, 301 Xuefu Road, Zhenjiang, 212013, Jiangsu Province, People's Republic of China
| | - Keping Chen
- School of Life Sciences, Jiangsu University, 301 Xuefu Road, Zhenjiang, 212013, Jiangsu Province, People's Republic of China
| |
Collapse
|
9
|
Wang J, Teng Y, Gong X, Zhang J, Wu Y, Lou L, Li M, Xie ZR, Yan Y. Exploring and engineering PAM-diverse Streptococci Cas9 for PAM-directed bifunctional and titratable gene control in bacteria. Metab Eng 2023; 75:68-77. [PMID: 36404524 PMCID: PMC10947553 DOI: 10.1016/j.ymben.2022.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 10/05/2022] [Accepted: 10/23/2022] [Indexed: 11/18/2022]
Abstract
The RNA-guided Cas9s serve as powerful tools for programmable gene editing and regulation; their targeting scopes and efficacies, however, are always constrained by the PAM sequence stringency. Most Streptococci Cas9s, including the prototype SpCas9 from S. pyogenes, specifically recognize a canonical NGG PAM via a conserved RxR PAM-binding motif within the PAM-interaction (PI) domain. Here, SpCas9-based mining unveils three distinct and rarely presented PAM-binding motifs (QxxxR, QxQ and RxQ) among Streptococci Cas9 orthologs. With the catalytically-dead QxxxR-containing SedCas9 from S. equinus, we dissect its NAG PAM specificity and elucidate its underlying recognition mechanism via computational prediction and mutagenesis analysis. Replacing the SedCas9 PI domain with alternate PAM-binding motifs rewires its PAM specificity to NGG or NAA. Moreover, a semi-rational design with minimal mutation creates a SedCas9-NQ variant showing robust activity towards expanded NNG and NAA PAMs, based upon which we engineered a compact ω-SedCas9-NQ transcriptional regulator for PAM-directed bifunctional and titratable gene control. The ω-SedCas9-NQ mediated metabolic reprogramming of endogenous genes in Escherichia coli affords a 2.6-fold increase of 4-hydroxycoumarin production. This work reveals new Cas9 scaffolds with distinct PAM-binding motifs for PAM relaxation and creates a new PAM-diverse Cas9 variant for versatile gene control in bacteria.
Collapse
Affiliation(s)
- Jian Wang
- School of Chemical, Materials and Biomedical Engineering, College of Engineering, The University of Georgia, Athens, GA, 30602, USA
| | - Yuxi Teng
- School of Chemical, Materials and Biomedical Engineering, College of Engineering, The University of Georgia, Athens, GA, 30602, USA
| | - Xinyu Gong
- School of Chemical, Materials and Biomedical Engineering, College of Engineering, The University of Georgia, Athens, GA, 30602, USA
| | - Jianli Zhang
- School of Chemical, Materials and Biomedical Engineering, College of Engineering, The University of Georgia, Athens, GA, 30602, USA
| | - Yifei Wu
- School of Electrical and Computer Engineering, College of Engineering, The University of Georgia, Athens, GA, 30602, USA
| | - Lei Lou
- School of Electrical and Computer Engineering, College of Engineering, The University of Georgia, Athens, GA, 30602, USA
| | - Michelle Li
- North Oconee High School, Bogart, GA, 30622, USA
| | - Zhong-Ru Xie
- School of Electrical and Computer Engineering, College of Engineering, The University of Georgia, Athens, GA, 30602, USA
| | - Yajun Yan
- School of Chemical, Materials and Biomedical Engineering, College of Engineering, The University of Georgia, Athens, GA, 30602, USA.
| |
Collapse
|
10
|
Kiattisewee C, Karanjia AV, Legut M, Daniloski Z, Koplik SE, Nelson J, Kleinstiver BP, Sanjana NE, Carothers JM, Zalatan JG. Expanding the Scope of Bacterial CRISPR Activation with PAM-Flexible dCas9 Variants. ACS Synth Biol 2022; 11:4103-4112. [PMID: 36378874 PMCID: PMC10516241 DOI: 10.1021/acssynbio.2c00405] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
CRISPR-Cas transcriptional tools have been widely applied for programmable regulation of complex biological networks. In comparison to eukaryotic systems, bacterial CRISPR activation (CRISPRa) has stringent target site requirements for effective gene activation. While genes may not always have an NGG protospacer adjacent motif (PAM) at the appropriate position, PAM-flexible dCas9 variants can expand the range of targetable sites. Here we systematically evaluate a panel of PAM-flexible dCas9 variants for their ability to activate bacterial genes. We observe that dxCas9-NG provides a high dynamic range of gene activation for sites with NGN PAMs while dSpRY permits modest activity across almost any PAM. Similar trends were observed for heterologous and endogenous promoters. For all variants tested, improved PAM-flexibility comes with the trade-off that CRISPRi-mediated gene repression becomes less effective. Weaker CRISPR interference (CRISPRi) gene repression can be partially rescued by expressing multiple sgRNAs to target many sites in the gene of interest. Our work provides a framework to choose the most effective dCas9 variant for a given set of gene targets, which will further expand the utility of CRISPRa/i gene regulation in bacterial systems.
Collapse
Affiliation(s)
- Cholpisit Kiattisewee
- Molecular Engineering & Sciences Institute and Center
for Synthetic Biology, University of Washington, Seattle, WA 98195, United
States
| | - Ava V. Karanjia
- Molecular Engineering & Sciences Institute and Center
for Synthetic Biology, University of Washington, Seattle, WA 98195, United
States
- Department of Chemical Engineering, University of
Washington, Seattle, WA 98195, United States
| | - Mateusz Legut
- New York Genome Center, New York, NY 10013, United
States
- Department of Biology, New York University, New York, NY
10013, United States
| | - Zharko Daniloski
- New York Genome Center, New York, NY 10013, United
States
- Department of Biology, New York University, New York, NY
10013, United States
| | - Samantha E. Koplik
- Department of Bioengineering, University of Washington,
Seattle, WA 98195, United States
| | - Joely Nelson
- Molecular Engineering & Sciences Institute and Center
for Synthetic Biology, University of Washington, Seattle, WA 98195, United
States
| | - Benjamin P. Kleinstiver
- Center for Genomic Medicine, Massachusetts General
Hospital, Boston, MA 02114, United States
- Department of Pathology, Massachusetts General Hospital,
Boston, MA 02114, United States
- Department of Pathology, Harvard Medical School, Boston,
MA 02115, United States
| | - Neville E. Sanjana
- New York Genome Center, New York, NY 10013, United
States
- Department of Biology, New York University, New York, NY
10013, United States
| | - James M. Carothers
- Molecular Engineering & Sciences Institute and Center
for Synthetic Biology, University of Washington, Seattle, WA 98195, United
States
- Department of Chemical Engineering, University of
Washington, Seattle, WA 98195, United States
- Department of Bioengineering, University of Washington,
Seattle, WA 98195, United States
| | - Jesse G. Zalatan
- Molecular Engineering & Sciences Institute and Center
for Synthetic Biology, University of Washington, Seattle, WA 98195, United
States
- Department of Chemical Engineering, University of
Washington, Seattle, WA 98195, United States
- Department of Chemistry, University of Washington,
Seattle, WA 98195, United States
| |
Collapse
|
11
|
Tickman BI, Burbano DA, Chavali VP, Kiattisewee C, Fontana J, Khakimzhan A, Noireaux V, Zalatan JG, Carothers JM. Multi-layer CRISPRa/i circuits for dynamic genetic programs in cell-free and bacterial systems. Cell Syst 2022; 13:215-229.e8. [PMID: 34800362 DOI: 10.1016/j.cels.2021.10.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 08/24/2021] [Accepted: 10/26/2021] [Indexed: 11/29/2022]
Abstract
CRISPR-Cas transcriptional circuits hold great promise as platforms for engineering metabolic networks and information processing circuits. Historically, prokaryotic CRISPR control systems have been limited to CRISPRi. Creating approaches to integrate CRISPRa for transcriptional activation with existing CRISPRi-based systems would greatly expand CRISPR circuit design space. Here, we develop design principles for engineering prokaryotic CRISPRa/i genetic circuits with network topologies specified by guide RNAs. We demonstrate that multi-layer CRISPRa/i cascades and feedforward loops can operate through the regulated expression of guide RNAs in cell-free expression systems and E. coli. We show that CRISPRa/i circuits can program complex functions by designing type 1 incoherent feedforward loops acting as fold-change detectors and tunable pulse-generators. By investigating how component characteristics relate to network properties such as depth, width, and speed, this work establishes a framework for building scalable CRISPRa/i circuits as regulatory programs in cell-free expression systems and bacterial hosts. A record of this paper's transparent peer review process is included in the supplemental information.
Collapse
Affiliation(s)
- Benjamin I Tickman
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, WA 98195, USA
| | - Diego Alba Burbano
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, WA 98195, USA; Department of Chemical Engineering, University of Washington, Seattle, WA 98195, USA
| | - Venkata P Chavali
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, WA 98195, USA
| | - Cholpisit Kiattisewee
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, WA 98195, USA
| | - Jason Fontana
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, WA 98195, USA
| | - Aset Khakimzhan
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA
| | - Vincent Noireaux
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA
| | - Jesse G Zalatan
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, WA 98195, USA; Department of Chemistry, University of Washington, Seattle, WA 98195, USA.
| | - James M Carothers
- Molecular Engineering & Sciences Institute and Center for Synthetic Biology, University of Washington, Seattle, WA 98195, USA; Department of Chemical Engineering, University of Washington, Seattle, WA 98195, USA.
| |
Collapse
|
12
|
Qu L, Xiu X, Sun G, Zhang C, Yang H, Liu Y, Li J, Du G, Lv X, Liu L. Engineered yeast for efficient de novo synthesis of 7‐dehydrocholesterol. Biotechnol Bioeng 2022; 119:1278-1289. [DOI: 10.1002/bit.28055] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 01/22/2022] [Accepted: 02/01/2022] [Indexed: 02/02/2023]
Affiliation(s)
- Lisha Qu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education Jiangnan University Wuxi Jiangsu China
- Science Center for Future Foods Jiangnan University Wuxi Jiangsu China
| | - Xiang Xiu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education Jiangnan University Wuxi Jiangsu China
- Science Center for Future Foods Jiangnan University Wuxi Jiangsu China
| | - Guoyun Sun
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education Jiangnan University Wuxi Jiangsu China
- Science Center for Future Foods Jiangnan University Wuxi Jiangsu China
| | - Chenyang Zhang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education Jiangnan University Wuxi Jiangsu China
- Science Center for Future Foods Jiangnan University Wuxi Jiangsu China
| | - Haiquan Yang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education Jiangnan University Wuxi Jiangsu China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education Jiangnan University Wuxi Jiangsu China
- Science Center for Future Foods Jiangnan University Wuxi Jiangsu China
| | - Jianghua Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education Jiangnan University Wuxi Jiangsu China
- Science Center for Future Foods Jiangnan University Wuxi Jiangsu China
| | - Guocheng Du
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education Jiangnan University Wuxi Jiangsu China
- Science Center for Future Foods Jiangnan University Wuxi Jiangsu China
| | - Xueqin Lv
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education Jiangnan University Wuxi Jiangsu China
- Science Center for Future Foods Jiangnan University Wuxi Jiangsu China
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education Jiangnan University Wuxi Jiangsu China
- Science Center for Future Foods Jiangnan University Wuxi Jiangsu China
| |
Collapse
|
13
|
Tarnowski MJ, Gorochowski TE. Massively parallel characterization of engineered transcript isoforms using direct RNA sequencing. Nat Commun 2022; 13:434. [PMID: 35064117 PMCID: PMC8783025 DOI: 10.1038/s41467-022-28074-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 01/07/2022] [Indexed: 12/23/2022] Open
Abstract
Transcriptional terminators signal where transcribing RNA polymerases (RNAPs) should halt and disassociate from DNA. However, because termination is stochastic, two different forms of transcript could be produced: one ending at the terminator and the other reading through. An ability to control the abundance of these transcript isoforms would offer bioengineers a mechanism to regulate multi-gene constructs at the level of transcription. Here, we explore this possibility by repurposing terminators as 'transcriptional valves' that can tune the proportion of RNAP read-through. Using one-pot combinatorial DNA assembly, we iteratively construct 1780 transcriptional valves for T7 RNAP and show how nanopore-based direct RNA sequencing (dRNA-seq) can be used to characterize entire libraries of valves simultaneously at a nucleotide resolution in vitro and unravel genetic design principles to tune and insulate termination. Finally, we engineer valves for multiplexed regulation of CRISPR guide RNAs. This work provides new avenues for controlling transcription and demonstrates the benefits of long-read sequencing for exploring complex sequence-function landscapes.
Collapse
Affiliation(s)
- Matthew J Tarnowski
- School of Biological Sciences, University of Bristol, Tyndall Avenue, Bristol, BS8 1TQ, UK
| | - Thomas E Gorochowski
- School of Biological Sciences, University of Bristol, Tyndall Avenue, Bristol, BS8 1TQ, UK.
- BrisSynBio, University of Bristol, Tyndall Avenue, Bristol, BS8 1TQ, UK.
| |
Collapse
|
14
|
Ziegler M, Hägele L, Gäbele T, Takors R. CRISPRi enables fast growth followed by stable aerobic pyruvate formation in
Escherichia coli
without auxotrophy. Eng Life Sci 2021; 22:70-84. [PMID: 35140555 PMCID: PMC8811725 DOI: 10.1002/elsc.202100021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 10/06/2021] [Accepted: 11/10/2021] [Indexed: 11/13/2022] Open
Abstract
CRISPR interference (CRISPRi) was applied to enable the aerobic production of pyruvate in Escherichia coli MG1655 under glucose excess conditions by targeting the promoter regions of aceE or pdhR. Knockdown strains were cultivated in aerobic shaking flasks and the influence of inducer concentration and different sgRNA binding sites on the production of pyruvate was measured. Targeting the promoter regions of aceE or pdhR triggered pyruvate production during the exponential phase and reduced expression of aceE. In lab‐scale bioreactor fermentations, an aceE silenced strain successfully produced pyruvate under fully aerobic conditions during the exponential phase, but loss of productivity occurred during a subsequent nitrogen‐limited phase. Targeting the promoter region of pdhR enabled pyruvate production during the growth phase of cultivations, and a continued low‐level accumulation during the nitrogen‐limited production phase. Combinatorial targeting of the promoter regions of both aceE and pdhR in E. coli MG1655 pdCas9 psgRNA_aceE_234_pdhR_329 resulted in the stable aerobic production of pyruvate with non‐growing cells at YP/S = 0.36 ± 0.029 gPyruvate/gGlucose in lab‐scale bioreactors throughout an extended nitrogen‐limited production phase.
Collapse
Affiliation(s)
- Martin Ziegler
- Institute of Biochemical Engineering University of Stuttgart Stuttgart Germany
| | - Lorena Hägele
- Institute of Biochemical Engineering University of Stuttgart Stuttgart Germany
| | - Teresa Gäbele
- Institute of Biochemical Engineering University of Stuttgart Stuttgart Germany
| | - Ralf Takors
- Institute of Biochemical Engineering University of Stuttgart Stuttgart Germany
| |
Collapse
|
15
|
Zocca VFB, Corrêa GG, Lins MRDCR, de Jesus VN, Tavares LF, Amorim LADS, Kundlatsch GE, Pedrolli DB. The CRISPR toolbox for the gram-positive model bacterium Bacillus subtilis. Crit Rev Biotechnol 2021; 42:813-826. [PMID: 34719304 DOI: 10.1080/07388551.2021.1983516] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
CRISPR has revolutionized the way we engineer genomes. Its simplicity and modularity have enabled the development of a great number of tools to edit genomes and to control gene expression. This powerful technology was first adapted to Bacillus subtilis in 2016 and has been intensely upgraded since then. Many tools have been successfully developed to build a CRISPR toolbox for this Gram-positive model and important industrial chassis. The toolbox includes tools, such as double-strand and single-strand cutting CRISPR for point mutation, gene insertion, and gene deletion up to 38 kb. Moreover, catalytic dead Cas proteins have been used for base editing, as well as for the control of gene expression (CRISPRi and CRISPRa). Many of these tools have been used for multiplex CRISPR with the most successful one targeting up to six loci simultaneously for point mutation. However, tools for efficient multiplex CRISPR for other functionalities are still missing in the toolbox. CRISPR engineering has already resulted in efficient protein and metabolite-producing strains, demonstrating its great potential. In this review, we cover all the important additions made to the B. subtilis CRISPR toolbox since 2016, and strain developments fomented by the technology.
Collapse
Affiliation(s)
- Vitoria Fernanda Bertolazzi Zocca
- Department of Bioprocess Engineering and Biotechnology, School of Pharmaceutical Sciences, Universidade Estadual Paulista (UNESP), Araraquara, Brazil
| | - Graciely Gomes Corrêa
- Department of Bioprocess Engineering and Biotechnology, School of Pharmaceutical Sciences, Universidade Estadual Paulista (UNESP), Araraquara, Brazil
| | - Milca Rachel da Costa Ribeiro Lins
- Department of Bioprocess Engineering and Biotechnology, School of Pharmaceutical Sciences, Universidade Estadual Paulista (UNESP), Araraquara, Brazil
| | - Victor Nunes de Jesus
- Department of Bioprocess Engineering and Biotechnology, School of Pharmaceutical Sciences, Universidade Estadual Paulista (UNESP), Araraquara, Brazil
| | - Leonardo Ferro Tavares
- Department of Bioprocess Engineering and Biotechnology, School of Pharmaceutical Sciences, Universidade Estadual Paulista (UNESP), Araraquara, Brazil
| | - Laura Araujo da Silva Amorim
- Department of Bioprocess Engineering and Biotechnology, School of Pharmaceutical Sciences, Universidade Estadual Paulista (UNESP), Araraquara, Brazil
| | - Guilherme Engelberto Kundlatsch
- Department of Bioprocess Engineering and Biotechnology, School of Pharmaceutical Sciences, Universidade Estadual Paulista (UNESP), Araraquara, Brazil
| | - Danielle Biscaro Pedrolli
- Department of Bioprocess Engineering and Biotechnology, School of Pharmaceutical Sciences, Universidade Estadual Paulista (UNESP), Araraquara, Brazil
| |
Collapse
|
16
|
Shakiba N, Jones RD, Weiss R, Del Vecchio D. Context-aware synthetic biology by controller design: Engineering the mammalian cell. Cell Syst 2021; 12:561-592. [PMID: 34139166 PMCID: PMC8261833 DOI: 10.1016/j.cels.2021.05.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 04/19/2021] [Accepted: 05/14/2021] [Indexed: 12/25/2022]
Abstract
The rise of systems biology has ushered a new paradigm: the view of the cell as a system that processes environmental inputs to drive phenotypic outputs. Synthetic biology provides a complementary approach, allowing us to program cell behavior through the addition of synthetic genetic devices into the cellular processor. These devices, and the complex genetic circuits they compose, are engineered using a design-prototype-test cycle, allowing for predictable device performance to be achieved in a context-dependent manner. Within mammalian cells, context effects impact device performance at multiple scales, including the genetic, cellular, and extracellular levels. In order for synthetic genetic devices to achieve predictable behaviors, approaches to overcome context dependence are necessary. Here, we describe control systems approaches for achieving context-aware devices that are robust to context effects. We then consider cell fate programing as a case study to explore the potential impact of context-aware devices for regenerative medicine applications.
Collapse
Affiliation(s)
- Nika Shakiba
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| | - Ross D Jones
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| | - Ron Weiss
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| | - Domitilla Del Vecchio
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| |
Collapse
|
17
|
Jervis AJ, Hanko EK, Dunstan MS, Robinson CJ, Takano E, Scrutton NS. A plasmid toolset for CRISPR-mediated genome editing and CRISPRi gene regulation in Escherichia coli. Microb Biotechnol 2021; 14:1120-1129. [PMID: 33710766 PMCID: PMC8085919 DOI: 10.1111/1751-7915.13780] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 02/09/2021] [Indexed: 12/29/2022] Open
Abstract
CRISPR technologies have become standard laboratory tools for genetic manipulations across all kingdoms of life. Despite their origins in bacteria, the development of CRISPR tools for engineering bacteria has been slower than for eukaryotes; nevertheless, their function and application for genome engineering and gene regulation via CRISPR interference (CRISPRi) has been demonstrated in various bacteria, and adoption has become more widespread. Here, we provide simple plasmid-based systems for genome editing (gene knockouts/knock-ins, and genome integration of large DNA fragments) and CRISPRi in E. coli using a CRISPR-Cas12a system. The described genome engineering protocols allow markerless deletion or genome integration in just seven working days with high efficiency (> 80% and 50%, respectively), and the CRISPRi protocols allow robust transcriptional repression of target genes (> 90%) with a single cloning step. The presented minimized plasmids and their associated design and experimental protocols provide efficient and effective CRISPR-Cas12 genome editing, genome integration and CRISPRi implementation. These simple-to-use systems and protocols will allow the easy adoption of CRISPR technology by any laboratory.
Collapse
Affiliation(s)
- Adrian J. Jervis
- Manchester Centre for Fine and Speciality Chemicals (SYNBIOCHEM)Manchester Institute of BiotechnologyUniversity of ManchesterManchesterM1 7DNUK
| | - Erik K.R. Hanko
- Manchester Centre for Fine and Speciality Chemicals (SYNBIOCHEM)Manchester Institute of BiotechnologyUniversity of ManchesterManchesterM1 7DNUK
| | - Mark S. Dunstan
- Manchester Centre for Fine and Speciality Chemicals (SYNBIOCHEM)Manchester Institute of BiotechnologyUniversity of ManchesterManchesterM1 7DNUK
| | - Christopher J. Robinson
- Manchester Centre for Fine and Speciality Chemicals (SYNBIOCHEM)Manchester Institute of BiotechnologyUniversity of ManchesterManchesterM1 7DNUK
| | - Eriko Takano
- Manchester Centre for Fine and Speciality Chemicals (SYNBIOCHEM)Manchester Institute of BiotechnologyUniversity of ManchesterManchesterM1 7DNUK
| | - Nigel S. Scrutton
- Manchester Centre for Fine and Speciality Chemicals (SYNBIOCHEM)Manchester Institute of BiotechnologyUniversity of ManchesterManchesterM1 7DNUK
| |
Collapse
|
18
|
Schultenkämper K, Gütle DD, López MG, Keller LB, Zhang L, Einsle O, Jacquot JP, Wendisch VF. Interrogating the Role of the Two Distinct Fructose-Bisphosphate Aldolases of Bacillus methanolicus by Site-Directed Mutagenesis of Key Amino Acids and Gene Repression by CRISPR Interference. Front Microbiol 2021; 12:669220. [PMID: 33995334 PMCID: PMC8119897 DOI: 10.3389/fmicb.2021.669220] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 03/30/2021] [Indexed: 12/13/2022] Open
Abstract
The Gram-positive Bacillus methanolicus shows plasmid-dependent methylotrophy. This facultative ribulose monophosphate (RuMP) cycle methylotroph possesses two fructose bisphosphate aldolases (FBA) with distinct kinetic properties. The chromosomally encoded FBAC is the major glycolytic aldolase. The gene for the major gluconeogenic aldolase FBAP is found on the natural plasmid pBM19 and is induced during methylotrophic growth. The crystal structures of both enzymes were solved at 2.2 Å and 2.0 Å, respectively, and they suggested amino acid residue 51 to be crucial for binding fructose-1,6-bisphosphate (FBP) as substrate and amino acid residue 140 for active site zinc atom coordination. As FBAC and FBAP differed at these positions, site-directed mutagenesis (SDM) was performed to exchange one or both amino acid residues of the respective proteins. The aldol cleavage reaction was negatively affected by the amino acid exchanges that led to a complete loss of glycolytic activity of FBAP. However, both FBAC and FBAP maintained gluconeogenic aldol condensation activity, and the amino acid exchanges improved the catalytic efficiency of the major glycolytic aldolase FBAC in gluconeogenic direction at least 3-fold. These results confirmed the importance of the structural differences between FBAC and FBAP concerning their distinct enzymatic properties. In order to investigate the physiological roles of both aldolases, the expression of their genes was repressed individually by CRISPR interference (CRISPRi). The fba C RNA levels were reduced by CRISPRi, but concomitantly the fba P RNA levels were increased. Vice versa, a similar compensatory increase of the fba C RNA levels was observed when fba P was repressed by CRISPRi. In addition, targeting fba P decreased tkt P RNA levels since both genes are cotranscribed in a bicistronic operon. However, reduced tkt P RNA levels were not compensated for by increased RNA levels of the chromosomal transketolase gene tkt C.
Collapse
Affiliation(s)
- Kerstin Schultenkämper
- Genetics of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, Bielefeld, Germany
| | | | - Marina Gil López
- Genetics of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, Bielefeld, Germany
| | - Laura B Keller
- Genetics of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, Bielefeld, Germany
| | - Lin Zhang
- Institute for Biochemistry, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Oliver Einsle
- Institute for Biochemistry, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | | | - Volker F Wendisch
- Genetics of Prokaryotes, Faculty of Biology & CeBiTec, Bielefeld University, Bielefeld, Germany
| |
Collapse
|
19
|
Zhang R, Xu W, Shao S, Wang Q. Gene Silencing Through CRISPR Interference in Bacteria: Current Advances and Future Prospects. Front Microbiol 2021; 12:635227. [PMID: 33868193 PMCID: PMC8044314 DOI: 10.3389/fmicb.2021.635227] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/24/2021] [Indexed: 11/30/2022] Open
Abstract
Functional genetic screening is an important method that has been widely used to explore the biological processes and functional annotation of genetic elements. CRISPR/Cas (Clustered regularly interspaced short palindromic repeat sequences/CRISPR-associated protein) is the newest tool in the geneticist's toolbox, allowing researchers to edit a genome with unprecedented ease, accuracy, and high-throughput. Most recently, CRISPR interference (CRISPRi) has been developed as an emerging technology that exploits the catalytically inactive Cas9 (dCas9) and single-guide RNA (sgRNA) to repress sequence-specific genes. In this review, we summarized the characteristics of the CRISPRi system, such as programmable, highly efficient, and specific. Moreover, we demonstrated its applications in functional genetic screening and highlighted its potential to dissect the underlying mechanism of pathogenesis. The recent development of the CRISPRi system will provide a high-throughput, practical, and efficient tool for the discovery of functionally important genes in bacteria.
Collapse
Affiliation(s)
- Riyu Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Wensheng Xu
- Laboratory of Agricultural Product Detection and Control of Spoilage Organisms and Pesticide Residue, Faculty of Food Science and Engineering, Beijing University of Agriculture, Beijing, China
| | - Shuai Shao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Qiyao Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
- Shanghai Collaborative Innovation Center for Biomanufacturing Technology, Shanghai, China
- Shanghai Engineering Research Center of Maricultured Animal Vaccines, Shanghai, China
| |
Collapse
|
20
|
Essential gene analysis in Acinetobacter baumannii by high-density transposon mutagenesis and CRISPR interference. J Bacteriol 2021; 203:e0056520. [PMID: 33782056 DOI: 10.1128/jb.00565-20] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Acinetobacter baumannii is a poorly understood bacterium capable of life-threatening infections in hospitals. Few antibiotics remain effective against this highly resistant pathogen. Developing rationally-designed antimicrobials that can target A. baumannii requires improved knowledge of the proteins that carry out essential processes allowing growth of the organism. Unfortunately, studying essential genes has been challenging using traditional techniques, which usually require time-consuming recombination-based genetic manipulations. Here, we performed saturating mutagenesis with dual transposon systems to identify essential genes in A. baumannii and we developed a CRISPR-interference (CRISPRi) system for facile analysis of these genes. We show that the CRISPRi system enables efficient transcriptional silencing in A. baumannii Using these tools, we confirmed the essentiality of the novel cell division protein AdvA and discovered a previously uncharacterized AraC-family transcription factor (ACX60_RS03245) that is necessary for growth. In addition, we show that capsule biosynthesis is a conditionally essential process, with mutations in late-acting steps causing toxicity in strain ATCC 17978 that can be bypassed by blocking early-acting steps or activating the BfmRS stress response. These results open new avenues for analysis of essential pathways in A. baumannii ImportanceNew approaches are urgently needed to control A. baumannii, one of the most drug resistant pathogens known. To facilitate the development of novel targets that allow inhibition of the pathogen, we performed a large-scale identification of genes whose products the bacterium needs for growth. We also developed a CRISPR-based gene knockdown tool that operates efficiently in A. baumannii, allowing rapid analysis of these essential genes. We used these methods to define multiple processes vital to the bacterium, including a previously uncharacterized gene-regulatory factor and export of a protective polymeric capsule. These tools will enhance our ability to investigate processes critical for the essential biology of this challenging hospital-acquired pathogen.
Collapse
|
21
|
Huang HH, Bellato M, Qian Y, Cárdenas P, Pasotti L, Magni P, Del Vecchio D. dCas9 regulator to neutralize competition in CRISPRi circuits. Nat Commun 2021; 12:1692. [PMID: 33727557 PMCID: PMC7966764 DOI: 10.1038/s41467-021-21772-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 01/29/2021] [Indexed: 12/17/2022] Open
Abstract
CRISPRi-mediated gene regulation allows simultaneous control of many genes. However, highly specific sgRNA-promoter binding is, alone, insufficient to achieve independent transcriptional regulation of multiple targets. Indeed, due to competition for dCas9, the repression ability of one sgRNA changes significantly when another sgRNA becomes expressed. To solve this problem and decouple sgRNA-mediated regulatory paths, we create a dCas9 concentration regulator that implements negative feedback on dCas9 level. This allows any sgRNA to maintain an approximately constant dose-response curve, independent of other sgRNAs. We demonstrate the regulator performance on both single-stage and layered CRISPRi-based genetic circuits, zeroing competition effects of up to 15-fold changes in circuit I/O response encountered without the dCas9 regulator. The dCas9 regulator decouples sgRNA-mediated regulatory paths, enabling concurrent and independent regulation of multiple genes. This allows predictable composition of CRISPRi-based genetic modules, which is essential in the design of larger scale synthetic genetic circuits.
Collapse
Affiliation(s)
- Hsin-Ho Huang
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Massimo Bellato
- Laboratory of Bioinformatics, Mathematical Modelling and Synthetic Biology, Department of Electrical, Computer and Biomedical Engineering, University of Pavia, Pavia, Italy
| | - Yili Qian
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Pablo Cárdenas
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Lorenzo Pasotti
- Laboratory of Bioinformatics, Mathematical Modelling and Synthetic Biology, Department of Electrical, Computer and Biomedical Engineering, University of Pavia, Pavia, Italy
| | - Paolo Magni
- Laboratory of Bioinformatics, Mathematical Modelling and Synthetic Biology, Department of Electrical, Computer and Biomedical Engineering, University of Pavia, Pavia, Italy
| | - Domitilla Del Vecchio
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Synthetic Biology Center, Massachusetts Institute of Technology, Cambridge, MA, USA.
| |
Collapse
|
22
|
Todor H, Silvis MR, Osadnik H, Gross CA. Bacterial CRISPR screens for gene function. Curr Opin Microbiol 2020; 59:102-109. [PMID: 33285498 DOI: 10.1016/j.mib.2020.11.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 11/03/2020] [Accepted: 11/04/2020] [Indexed: 12/16/2022]
Abstract
In this review we describe the application of CRISPR tools for functional genomics screens in bacteria, with a focus on the use of interference (CRISPRi) approaches. We review recent developments in CRISPRi titration, which has enabled essential gene functional screens, and genome-scale pooled CRISPRi screens. We summarize progress toward enabling CRISPRi screens in non-model and pathogenic bacteria, including the development of new dCas9 variants. Taking into account the current state of the field, we provide a forward-looking analysis of CRISPRi strategies for determining gene function in bacteria.
Collapse
Affiliation(s)
- Horia Todor
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Melanie R Silvis
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Hendrik Osadnik
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Carol A Gross
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94158, USA; Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA 94158, USA; California Institute of Quantitative Biology, University of California, San Francisco, San Francisco 94158 CA, USA.
| |
Collapse
|
23
|
Tian J, Yang G, Gu Y, Sun X, Lu Y, Jiang W. Developing an endogenous quorum-sensing based CRISPRi circuit for autonomous and tunable dynamic regulation of multiple targets in Streptomyces. Nucleic Acids Res 2020; 48:8188-8202. [PMID: 32672817 PMCID: PMC7430639 DOI: 10.1093/nar/gkaa602] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 07/01/2020] [Accepted: 07/15/2020] [Indexed: 12/12/2022] Open
Abstract
Quorum-sensing (QS) mediated dynamic regulation has emerged as an effective strategy for optimizing product titers in microbes. However, these QS-based circuits are often created on heterologous systems and require careful tuning via a tedious testing/optimization process. This hampers their application in industrial microbes. Here, we design a novel QS circuit by directly integrating an endogenous QS system with CRISPRi (named EQCi) in the industrial rapamycin-producing strain Streptomyces rapamycinicus. EQCi combines the advantages of both the QS system and CRISPRi to enable tunable, autonomous, and dynamic regulation of multiple targets simultaneously. Using EQCi, we separately downregulate three key nodes in essential pathways to divert metabolic flux towards rapamycin biosynthesis and significantly increase its titers. Further application of EQCi to simultaneously regulate these three key nodes with fine-tuned repression strength boosts the rapamycin titer by ∼660%, achieving the highest reported titer (1836 ± 191 mg/l). Notably, compared to static engineering strategies, which result in growth arrest and suboptimal rapamycin titers, EQCi-based regulation substantially promotes rapamycin titers without affecting cell growth, indicating that it can achieve a trade-off between essential pathways and product synthesis. Collectively, this study provides a convenient and effective strategy for strain improvement and shows potential for application in other industrial microorganisms.
Collapse
Affiliation(s)
- Jinzhong Tian
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences (CAS), Shanghai 200032, China.,University of Chinese Academy of Sciences, Beijing 100039, China
| | - Gaohua Yang
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences (CAS), Shanghai 200032, China.,University of Chinese Academy of Sciences, Beijing 100039, China
| | - Yang Gu
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences (CAS), Shanghai 200032, China
| | - Xinqiang Sun
- XinChang Pharmaceutical Factory, Zhejiang medicine LTD, Xinchang 312500, Zhejiang Province, China
| | - Yinhua Lu
- College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Weihong Jiang
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences (CAS), Shanghai 200032, China
| |
Collapse
|
24
|
Pattharaprachayakul N, Lee M, Incharoensakdi A, Woo HM. Current understanding of the cyanobacterial CRISPR-Cas systems and development of the synthetic CRISPR-Cas systems for cyanobacteria. Enzyme Microb Technol 2020; 140:109619. [PMID: 32912679 DOI: 10.1016/j.enzmictec.2020.109619] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 05/14/2020] [Accepted: 06/05/2020] [Indexed: 11/20/2022]
Abstract
Cyanobacteria are photosynthetic microorganisms that are capable of converting CO2 to value-added chemicals. Engineering of cyanobacteria with synthetic biology tools, including the CRISPR-Cas system, has allowed an opportunity for biological CO2 utilization. Here, we described natural CRISPR-Cas systems for understanding cyanobacterial genomics and synthetic CRISPR-Cas systems for metabolic engineering applications. The natural CRISPR-Cas systems in cyanobacteria have been identified as Class 1, with type I and III, and some Class 2, with type V, as an adaptive immune system against viral invasion. As synthetic tools, CRISPR-Cas9 and -Cas12a have been successfully established in cyanobacteria to delete a target gene without a selection marker. Deactivated Cas9 and Cas12a have also been used to repress genes for metabolic engineering. In addition, a perspective on how advanced CRISPR-Cas systems and a pool of the guide RNAs can be advantageous for precise genome engineering and understanding of unknown functions was discussed for advanced engineering of cyanobacteria.
Collapse
Affiliation(s)
- Napisa Pattharaprachayakul
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon, 16419, Republic of Korea; Laboratory of Cyanobacterial Biotechnology, Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok, 10330 Thailand; Program in Biotechnology, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok, 10330, Thailand
| | - Mieun Lee
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon, 16419, Republic of Korea
| | - Aran Incharoensakdi
- Laboratory of Cyanobacterial Biotechnology, Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok, 10330 Thailand
| | - Han Min Woo
- Department of Food Science and Biotechnology, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon, 16419, Republic of Korea; BioFoundry Research Center, Institute of Biotechnology and Bioengineering, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon, 16419, Republic of Korea.
| |
Collapse
|
25
|
Wu Y, Liu Y, Lv X, Li J, Du G, Liu L. Applications of CRISPR in a Microbial Cell Factory: From Genome Reconstruction to Metabolic Network Reprogramming. ACS Synth Biol 2020; 9:2228-2238. [PMID: 32794766 DOI: 10.1021/acssynbio.0c00349] [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] [Indexed: 02/08/2023]
Abstract
The well-designed microbial cell factory finds wide applications in chemical, pharmaceutical, and food industries due to its sustainable and environmentally friendly features. Recently, the clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated proteins (CRISPR-Cas) systems have been developed into powerful tools to perform genome editing and transcriptional regulation in prokaryotic and eukaryotic cells. Accordingly, these tools are useful to build microbial cell factories not only by reconstructing the genome but also by reprogramming the metabolic network. In this review, we summarize the recent significant headway and potential uses of the CRISPR technology in the construction of efficient microbial cell factories. Moreover, the future perspectives on the improvement and upgradation of CRISPR-based tools are also discussed.
Collapse
Affiliation(s)
- Yaokang Wu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Yanfeng Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Xueqin Lv
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Jianghua Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Guocheng Du
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| | - Long Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, Jiangnan University, Wuxi, 214122, China
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, China
| |
Collapse
|
26
|
Wang D, Wang H, Zhan Y, Xu Y, Deng J, Chen J, Cai D, Wang Q, Sheng F, Chen S. Engineering Expression Cassette of pgdS for Efficient Production of Poly-γ-Glutamic Acids With Specific Molecular Weights in Bacillus licheniformis. Front Bioeng Biotechnol 2020; 8:728. [PMID: 32754581 PMCID: PMC7381323 DOI: 10.3389/fbioe.2020.00728] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 06/09/2020] [Indexed: 12/13/2022] Open
Abstract
Poly-γ-glutamic acid (γ-PGA) is an emerging biopolymer with various applications and γ-PGAs with different molecular weights exhibit distinctive properties. However, studies on the controllable molecular weights of biopolymers are limited. The purpose of this study is to achieve production of γ-PGAs with a wide range of molecular weights through manipulating the expression of γ-PGA depolymerase (PgdS) in Bacillus licheniformis WX-02. Firstly, the expression and secretion of PgdS were regulated through engineering its expression elements (four promoters and eight signal peptides), which generated γ-PGAs with molecular weights ranging from 6.82 × 104 to 1.78 × 106 Da. Subsequently, through combination of promoters with signal peptides, the production of γ-PGAs with a specific molecular weight could be efficiently obtained. Interestingly, the γ-PGA yield increased with the reduced molecular weight in flask cultures (Pearson correlation coefficient of −0.968, P < 0.01). Finally, in batch fermentation, the highest yield of γ-PGA with a weight-average molecular weight of 7.80 × 104 Da reached 39.13 g/L under glutamate-free medium. Collectively, we developed an efficient strategy for one-step production of γ-PGAs with specific molecular weights, which have potential application for industrial production of desirable γ-PGAs.
Collapse
Affiliation(s)
- Dong Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Science, Hubei University, Wuhan, China
| | - Huan Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Science, Hubei University, Wuhan, China
| | - Yangyang Zhan
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Science, Hubei University, Wuhan, China
| | - Yong Xu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Science, Hubei University, Wuhan, China
| | - Jie Deng
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Science, Hubei University, Wuhan, China
| | | | - Dongbo Cai
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Science, Hubei University, Wuhan, China
| | - Qin Wang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Science, Hubei University, Wuhan, China
| | - Feng Sheng
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Science, Hubei University, Wuhan, China
| | - Shouwen Chen
- State Key Laboratory of Biocatalysis and Enzyme Engineering, Environmental Microbial Technology Center of Hubei Province, College of Life Science, Hubei University, Wuhan, China
| |
Collapse
|
27
|
Mo XH, Zhang H, Wang TM, Zhang C, Zhang C, Xing XH, Yang S. Establishment of CRISPR interference in Methylorubrum extorquens and application of rapidly mining a new phytoene desaturase involved in carotenoid biosynthesis. Appl Microbiol Biotechnol 2020; 104:4515-4532. [PMID: 32215707 DOI: 10.1007/s00253-020-10543-w] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 03/02/2020] [Accepted: 03/11/2020] [Indexed: 02/04/2023]
Abstract
The methylotrophic bacterium Methylorubrum extorquens AM1 holds a great potential of a microbial cell factory in producing high value chemicals with methanol as the sole carbon and energy source. However, many gene functions remain unknown, hampering further rewiring of metabolic networks. Clustered regularly interspaced short palindromic repeat interference (CRISPRi) has been demonstrated to be a robust tool for gene knockdown in diverse organisms. In this study, we developed an efficient CRISPRi system through optimizing the promoter strength of Streptococcus pyogenes-derived deactivated cas9 (dcas9). When the dcas9 and sgRNA were respectively controlled by medium PR/tetO and strong PmxaF-g promoters, dynamic repression efficacy of cell growth through disturbing a central metabolism gene glyA was achieved from 41.9 to 96.6% dependent on the sgRNA targeting sites. Furthermore, the optimized CRISPRi system was shown to effectively decrease the abundance of exogenous fluorescent protein gene mCherry over 50% and to reduce the expression of phytoene desaturase gene crtI by 97.7%. We then used CRISPRi technology combined with 26 sgRNAs pool to rapidly discover a new phytoene desaturase gene META1_3670 from 2470 recombinant mutants. The gene function was further verified through gene deletion and complementation as well as phylogenetic tree analysis. In addition, we applied CRISPRi to repress the transcriptional level of squalene-hopene cyclase gene shc involved in hopanoid biosynthesis by 64.9%, which resulted in enhancing 1.9-fold higher of carotenoid production without defective cell growth. Thus, the CRISPRi system developed here provides a useful tool in mining functional gene of M. extorquens as well as in biotechnology for producing high-valued chemicals from methanol. KEY POINTS: Developing an efficient CRISPRi to knockdown gene expression in C1-utilizing bacteria CRISPRi combined with sgRNAs pool to rapidly discover a new phytoene desaturase gene Improvement of carotenoid production by repressing a competitive pathway.
Collapse
Affiliation(s)
- Xu-Hua Mo
- School of Life Sciences, Shandong Province Key Laboratory of Applied Mycology, and Qingdao International Center on Microbes Utilizing Biogas, Qingdao Agricultural University, Qingdao, Shandong Province, People's Republic of China
| | - Hui Zhang
- School of Life Sciences, Shandong Province Key Laboratory of Applied Mycology, and Qingdao International Center on Microbes Utilizing Biogas, Qingdao Agricultural University, Qingdao, Shandong Province, People's Republic of China
| | - Tian-Min Wang
- Department of Chemical Engineering, Tsinghua University, Beijing, People's Republic of China
| | - Chong Zhang
- Department of Chemical Engineering, Tsinghua University, Beijing, People's Republic of China
| | - Cong Zhang
- School of Life Sciences, Shandong Province Key Laboratory of Applied Mycology, and Qingdao International Center on Microbes Utilizing Biogas, Qingdao Agricultural University, Qingdao, Shandong Province, People's Republic of China
| | - Xin-Hui Xing
- Department of Chemical Engineering, Tsinghua University, Beijing, People's Republic of China
| | - Song Yang
- School of Life Sciences, Shandong Province Key Laboratory of Applied Mycology, and Qingdao International Center on Microbes Utilizing Biogas, Qingdao Agricultural University, Qingdao, Shandong Province, People's Republic of China.
- Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin University, Tianjin, People's Republic of China.
| |
Collapse
|
28
|
Li M, Chen J, Wang Y, Liu J, Huang J, Chen N, Zheng P, Sun J. Efficient Multiplex Gene Repression by CRISPR-dCpf1 in Corynebacterium glutamicum. Front Bioeng Biotechnol 2020; 8:357. [PMID: 32391351 PMCID: PMC7193084 DOI: 10.3389/fbioe.2020.00357] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 03/31/2020] [Indexed: 01/14/2023] Open
Abstract
Corynebacterium glutamicum is an important workhorse for industrial production of diversiform bioproducts. Multiplex control of metabolic pathway genes is crucial for maximizing biosynthesis of desired products. However, few tools for simultaneously regulating multiple genes in C. glutamicum have been reported. Here, a CRISPR-dCpf1-based multiplex gene repression system was developed for C. glutamicum. This system successfully repressed two fluorescent reporter genes simultaneously by expressing a dCpf1 (E1006A, D917A) and a designed single crRNA array. To demonstrate applications of this CRISPR-dCpf1 system in metabolic engineering, we applied this system to repress four genes involved in lysine biosynthesis (gltA, pck, pgi, and hom) with a single array, which increased the lysine titer and yield for over 4.0-fold. Quantitative PCR demonstrated that transcription of all the four endogenous target genes were repressed by over 90%. Thus, the CRISPR-dCpf1 system is a simple and effective technique for multiplex gene repression in C. glutamicum and holds promise for metabolic engineering of C. glutamicum to produce valuable chemicals and fuels.
Collapse
Affiliation(s)
- Mingyue Li
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China.,Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Jiuzhou Chen
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Yu Wang
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Jiao Liu
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Jingwen Huang
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China.,School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Ning Chen
- College of Biotechnology, Tianjin University of Science and Technology, Tianjin, China
| | - Ping Zheng
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| | - Jibin Sun
- Key Laboratory of Systems Microbial Biotechnology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, China
| |
Collapse
|
29
|
Zhang J, Wang Z, Su T, Sun H, Zhu Y, Qi Q, Wang Q. Tuning the Binding Affinity of Heme-Responsive Biosensor for Precise and Dynamic Pathway Regulation. iScience 2020; 23:101067. [PMID: 32371371 PMCID: PMC7200772 DOI: 10.1016/j.isci.2020.101067] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Revised: 02/21/2020] [Accepted: 04/13/2020] [Indexed: 02/06/2023] Open
Abstract
Current challenge for dynamic pathway control in metabolic engineering is enabling the components of the artificial regulatory system to be tunable. Here, we designed and built a heme-responsive regulatory system containing a heme biosensor HrtR and CRISPRi to regulate chemicals production while maintaining the intracellular heme homeostasis. A series of engineered biosensors with varied sensitivity and threshold were obtained by semi-rational design with site saturated mutation of HrtR. The modified metabolite-binding affinity of HrtR was confirmed by heme titration and molecular dynamic simulation. Dynamic regulation pattern of the system was validated by the fluctuation of gene expression and intracellular heme concentration. The efficiency of this regulatory system was proved by improving the 5-aminolevulinic acid (ALA) production to 5.35g/L, the highest yield in batch fermentation of Escherichia coli. This system was also successfully used in improving porphobilinogen (PBG) and porphyrins biosynthesis and can be applied in many other biological processes. Designed and built a heme-responsive regulatory system employing HrtR and CRISPRi Turning the binding affinity of HrtR by site saturation mutations Optimizing the system to achieve dynamic regulation of target genes The system was applied to the ALA, PBG, and porphyrins production
Collapse
Affiliation(s)
- Jian Zhang
- State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Qingdao 266237, P. R. China
| | - Zhiguo Wang
- Institute of Ageing Research, School of Medicine, Hangzhou Normal University, Hangzhou 311121, P. R. China
| | - Tianyuan Su
- State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Qingdao 266237, P. R. China
| | - Huanhuan Sun
- State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Qingdao 266237, P. R. China
| | - Yuan Zhu
- State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Qingdao 266237, P. R. China
| | - Qingsheng Qi
- State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Qingdao 266237, P. R. China; CAS Key Lab of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, P. R. China.
| | - Qian Wang
- State Key Laboratory of Microbial Technology, National Glycoengineering Research Center, Shandong University, Qingdao 266237, P. R. China.
| |
Collapse
|
30
|
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
|
31
|
Schultenkämper K, Brito LF, Wendisch VF. Impact of CRISPR interference on strain development in biotechnology. Biotechnol Appl Biochem 2020; 67:7-21. [DOI: 10.1002/bab.1901] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 02/13/2020] [Indexed: 12/17/2022]
Affiliation(s)
| | - Luciana F. Brito
- Department of Biotechnology and Food ScienceNTNUNorwegian University of Science and Technology Trondheim Norway
| | | |
Collapse
|
32
|
Kent R, Dixon N. Contemporary Tools for Regulating Gene Expression in Bacteria. Trends Biotechnol 2019; 38:316-333. [PMID: 31679824 DOI: 10.1016/j.tibtech.2019.09.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 09/16/2019] [Accepted: 09/17/2019] [Indexed: 12/14/2022]
Abstract
Insights from novel mechanistic paradigms in gene expression control have led to the development of new gene expression systems for bioproduction, control, and sensing applications. Coupled with a greater understanding of synthetic burden and modern creative biodesign approaches, contemporary bacterial gene expression tools and systems are emerging that permit fine-tuning of expression, enabling greater predictability and maximisation of specific productivity, while minimising deleterious effects upon cell viability. These advances have been achieved by using a plethora of regulatory tools, operating at all levels of the so-called 'central dogma' of molecular biology. In this review, we discuss these gene regulation tools in the context of their design, prototyping, integration into expression systems, and biotechnological application.
Collapse
Affiliation(s)
- Ross Kent
- Manchester Institute of Biotechnology and School of Chemistry, University of Manchester, Manchester, UK
| | - Neil Dixon
- Manchester Institute of Biotechnology and School of Chemistry, University of Manchester, Manchester, UK.
| |
Collapse
|
33
|
Lu Q, Liu JZ. Enhanced Astaxanthin Production in Escherichia coli via Morphology and Oxidative Stress Engineering. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:11703-11709. [PMID: 31578056 DOI: 10.1021/acs.jafc.9b05404] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Astaxanthin is a carotenoid of high commercial value because of its excellent antioxidative, anti-inflammatory, and anticancer properties. Here, we developed a novel strategy for improving the production of astaxanthin via morphology and oxidative stress engineering. First, we identified the morphology-/membrane- and oxidative stress-related genes, which should be knocked down, using the CRISPRi system. Deleting the morphology-/membrane-related genes (lpp and bamB) and the oxidative stress-related genes (uspE and yggE) generated longer and larger cells with higher reactive oxygen species (ROS) levels, thus enhancing the production of astaxanthin and decreasing cell growth. To not only improve cell growth but also obtain longer and larger cells with higher ROS levels, a complementary expression system using a temperature-sensitive plasmid was established. Complementarily expressing the morphology-/membrane-related genes (lpp and bamB) and the oxidative stress-related genes (uspE and yggE) further improved the production of astaxanthin to 11.92 mg/g dry cell weight in shake flask cultures.
Collapse
Affiliation(s)
- Qian Lu
- Institute of Synthetic Biology, Biomedical Center, Guangdong Province Key Laboratory of Improved Variety Reproduction in Aquatic Economic Animals and South China Sea Bio-Resource Exploitation and Utilization Collaborative Innovation Center, School of Life Sciences , Sun Yat-sen University , Guangzhou 510275 , China
| | - Jian-Zhong Liu
- Institute of Synthetic Biology, Biomedical Center, Guangdong Province Key Laboratory of Improved Variety Reproduction in Aquatic Economic Animals and South China Sea Bio-Resource Exploitation and Utilization Collaborative Innovation Center, School of Life Sciences , Sun Yat-sen University , Guangzhou 510275 , China
| |
Collapse
|
34
|
Kundert K, Lucas JE, Watters KE, Fellmann C, Ng AH, Heineike BM, Fitzsimmons CM, Oakes BL, Qu J, Prasad N, Rosenberg OS, Savage DF, El-Samad H, Doudna JA, Kortemme T. Controlling CRISPR-Cas9 with ligand-activated and ligand-deactivated sgRNAs. Nat Commun 2019; 10:2127. [PMID: 31073154 PMCID: PMC6509140 DOI: 10.1038/s41467-019-09985-2] [Citation(s) in RCA: 113] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 04/10/2019] [Indexed: 12/26/2022] Open
Abstract
The CRISPR-Cas9 system provides the ability to edit, repress, activate, or mark any gene (or DNA element) by pairing of a programmable single guide RNA (sgRNA) with a complementary sequence on the DNA target. Here we present a new method for small-molecule control of CRISPR-Cas9 function through insertion of RNA aptamers into the sgRNA. We show that CRISPR-Cas9-based gene repression (CRISPRi) can be either activated or deactivated in a dose-dependent fashion over a >10-fold dynamic range in response to two different small-molecule ligands. Since our system acts directly on each target-specific sgRNA, it enables new applications that require differential and opposing temporal control of multiple genes.
Collapse
Affiliation(s)
- Kale Kundert
- Graduate Group in Biophysics, University of California San Francisco, San Francisco, CA, 94158, USA.
| | - James E Lucas
- UC Berkeley - UCSF Graduate Program in Bioengineering, University of California San Francisco, San Francisco, CA, 94158, USA
| | - Kyle E Watters
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, 94704, USA
| | - Christof Fellmann
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, 94704, USA
| | - Andrew H Ng
- UC Berkeley - UCSF Graduate Program in Bioengineering, University of California San Francisco, San Francisco, CA, 94158, USA
| | - Benjamin M Heineike
- Bioinformatics Graduate Program, University of California San Francisco, San Francisco, CA, 94158, USA
| | - Christina M Fitzsimmons
- Chemistry and Chemical Biology Graduate Program, University of California San Francisco, San Francisco, CA, 94158, USA
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Benjamin L Oakes
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, 94704, USA
| | - Jiuxin Qu
- Department of Medicine, University of California San Francisco, San Francisco, CA, 94158, USA
| | - Neha Prasad
- Department of Medicine, University of California San Francisco, San Francisco, CA, 94158, USA
| | - Oren S Rosenberg
- Department of Medicine, University of California San Francisco, San Francisco, CA, 94158, USA
- Chan Zuckerberg Biohub, San Francisco, CA, 94158, USA
| | - David F Savage
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, 94704, USA
| | - Hana El-Samad
- Chan Zuckerberg Biohub, San Francisco, CA, 94158, USA
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, 94158, USA
| | - Jennifer A Doudna
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, 94704, USA
- Howard Hughes Medical Institute, University of California Berkeley, Berkeley, CA, 94704, USA
| | - Tanja Kortemme
- Chan Zuckerberg Biohub, San Francisco, CA, 94158, USA.
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, 94158, USA.
| |
Collapse
|
35
|
Lee YJ, Kim SJ, Amrofell MB, Moon TS. Establishing a Multivariate Model for Predictable Antisense RNA-Mediated Repression. ACS Synth Biol 2019; 8:45-56. [PMID: 30517781 DOI: 10.1021/acssynbio.8b00227] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Recent advances in our understanding of RNA folding and functions have facilitated the use of regulatory RNAs such as synthetic antisense RNAs (asRNAs) to modulate gene expression. However, despite the simple and universal complementarity rule, predictable asRNA-mediated repression is still challenging due to the intrinsic complexity of native asRNA-mediated gene regulation. To address this issue, we present a multivariate model, based on the change in free energy of complex formation (Δ GCF) and percent mismatch of the target binding region, which can predict synthetic asRNA-mediated repression efficiency in diverse contexts. First, 69 asRNAs that bind to multiple target mRNAs were designed and tested to create the predictive model. Second, we showed that the same model is effective predicting repression of target genes in both plasmids and chromosomes. Third, using our model, we designed asRNAs that simultaneously modulated expression of a toxin and its antitoxin to demonstrate tunable control of cell growth. Fourth, we tested and validated the same model in two different biotechnologically important organisms: Escherichia coli Nissle 1917 and Bacillus subtilis 168. Last, multiple parameters, including target locations, the presence of an Hfq binding site, GC contents, and gene expression levels, were revisited to define the conditions under which the multivariate model should be used for accurate prediction. Together, 434 different strain-asRNA combinations were tested, validating the predictive model in a variety of contexts, including multiple target genes and organisms. The result presented in this study is an important step toward achieving predictable tunability of asRNA-mediated repression.
Collapse
Affiliation(s)
- Young Je Lee
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Soo-Jung Kim
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Matthew B. Amrofell
- 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
|
36
|
Alper HS, Beisel CL. Advances in CRISPR Technologies for Microbial Strain Engineering. Biotechnol J 2018; 13:e1800460. [PMID: 30175907 DOI: 10.1002/biot.201800460] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 07/26/2018] [Indexed: 11/08/2022]
Affiliation(s)
- Hal S Alper
- H. Alper, The University of Texas at Austin, USA
| | - Chase L Beisel
- Chase Beisel , Helmholtz Institute for RNA-based Infection Research, Germany
| |
Collapse
|
37
|
Abstract
CRISPR interference (CRISPRi) is widely utilized for regulation of target gene expression by repressing transcription. Simple design rules for the single guide RNA (sgRNA) and multiplexity won this method immense popularity. However, quantitative control of the expression levels at varying degrees in a dynamic manner using CRISPRi has been regarded difficult. To deal with this limitation, Fontana et al. modulated the expression levels of the components of CRISPRi, the deactivated Cas9 (dCas9), and the sgRNAs, using various constitutive or inducible promoters (Fontana et al., Biotechnol. J. 2018, 13, 1800069). They found that the expression level of sgRNA is the key to controlling CRISPRi. Modulation of sgRNA expression levels enabled quantitative tuning of the CRISPRi-regulated gene expression level. This approach is expected to be easily applied to diverse applications owing to its simplicity compared to the conventional approaches that modified target sequence or changed the expression level of dCas9.
Collapse
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
| | - 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
| |
Collapse
|
38
|
Fontana J, Voje WE, Zalatan JG, Carothers JM. Prospects for engineering dynamic CRISPR–Cas transcriptional circuits to improve bioproduction. ACTA ACUST UNITED AC 2018; 45:481-490. [DOI: 10.1007/s10295-018-2039-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 04/26/2018] [Indexed: 12/26/2022]
Abstract
Abstract
Dynamic control of gene expression is emerging as an important strategy for controlling flux in metabolic pathways and improving bioproduction of valuable compounds. Integrating dynamic genetic control tools with CRISPR–Cas transcriptional regulation could significantly improve our ability to fine-tune the expression of multiple endogenous and heterologous genes according to the state of the cell. In this mini-review, we combine an analysis of recent literature with examples from our own work to discuss the prospects and challenges of developing dynamically regulated CRISPR–Cas transcriptional control systems for applications in synthetic biology and metabolic engineering.
Collapse
Affiliation(s)
- Jason Fontana
- 0000000122986657 grid.34477.33 Molecular Engineering and Sciences Institute and Center for Synthetic Biology University of Washington 98195 Seattle WA USA
| | - William E Voje
- 0000000122986657 grid.34477.33 Molecular Engineering and Sciences Institute and Center for Synthetic Biology University of Washington 98195 Seattle WA USA
- 0000000122986657 grid.34477.33 Department of Chemical Engineering University of Washington 98195 Seattle WA USA
| | - Jesse G Zalatan
- 0000000122986657 grid.34477.33 Molecular Engineering and Sciences Institute and Center for Synthetic Biology University of Washington 98195 Seattle WA USA
- 0000000122986657 grid.34477.33 Department of Chemistry University of Washington 98195 Seattle WA USA
| | - James M Carothers
- 0000000122986657 grid.34477.33 Molecular Engineering and Sciences Institute and Center for Synthetic Biology University of Washington 98195 Seattle WA USA
- 0000000122986657 grid.34477.33 Department of Chemical Engineering University of Washington 98195 Seattle WA USA
| |
Collapse
|
39
|
Synthetic CRISPR-Cas gene activators for transcriptional reprogramming in bacteria. Nat Commun 2018; 9:2489. [PMID: 29950558 PMCID: PMC6021436 DOI: 10.1038/s41467-018-04901-6] [Citation(s) in RCA: 117] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 06/01/2018] [Indexed: 02/06/2023] Open
Abstract
Methods to regulate gene expression programs in bacterial cells are limited by the absence of effective gene activators. To address this challenge, we have developed synthetic bacterial transcriptional activators in E. coli by linking activation domains to programmable CRISPR-Cas DNA binding domains. Effective gene activation requires target sites situated in a narrow region just upstream of the transcription start site, in sharp contrast to the relatively flexible target site requirements for gene activation in eukaryotic cells. Together with existing tools for CRISPRi gene repression, these bacterial activators enable programmable control over multiple genes with simultaneous activation and repression. Further, the entire gene expression program can be switched on by inducing expression of the CRISPR-Cas system. This work will provide a foundation for engineering synthetic bacterial cellular devices with applications including diagnostics, therapeutics, and industrial biosynthesis. The absence of effective gene activators in bacteria limits regulated expression programs. Here the authors design synthetic bacterial CRISPR-Cas transcriptional activators that can be used to construct multi-gene programs of activation and repression.
Collapse
|