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Alba Burbano D, Cardiff RAL, Tickman BI, Kiattisewee C, Maranas CJ, Zalatan JG, Carothers JM. Engineering activatable promoters for scalable and multi-input CRISPRa/i circuits. Proc Natl Acad Sci U S A 2023; 120:e2220358120. [PMID: 37463216 PMCID: PMC10374173 DOI: 10.1073/pnas.2220358120] [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: 11/30/2022] [Accepted: 06/13/2023] [Indexed: 07/20/2023] Open
Abstract
Dynamic, multi-input gene regulatory networks (GRNs) are ubiquitous in nature. Multilayer CRISPR-based genetic circuits hold great promise for building GRNs akin to those found in naturally occurring biological systems. We develop an approach for creating high-performing activatable promoters that can be assembled into deep, wide, and multi-input CRISPR-activation and -interference (CRISPRa/i) GRNs. By integrating sequence-based design and in vivo screening, we engineer activatable promoters that achieve up to 1,000-fold dynamic range in an Escherichia coli-based cell-free system. These components enable CRISPRa GRNs that are six layers deep and four branches wide. We show the generalizability of the promoter engineering workflow by improving the dynamic range of the light-dependent EL222 optogenetic system from 6-fold to 34-fold. Additionally, high dynamic range promoters enable CRISPRa systems mediated by small molecules and protein-protein interactions. We apply these tools to build input-responsive CRISPRa/i GRNs, including feedback loops, logic gates, multilayer cascades, and dynamic pulse modulators. Our work provides a generalizable approach for the design of high dynamic range activatable promoters and enables classes of gene regulatory functions in cell-free systems.
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Affiliation(s)
- Diego Alba Burbano
- Department of Chemical Engineering, University of Washington, Seattle, WA98195
- Center for Synthetic Biology, University of Washington, Seattle, WA98195
| | - Ryan A. L. Cardiff
- Center for Synthetic Biology, University of Washington, Seattle, WA98195
- Molecular Engineering & Sciences Institute, University of Washington, Seattle, WA98195
| | - Benjamin I. Tickman
- Center for Synthetic Biology, University of Washington, Seattle, WA98195
- Molecular Engineering & Sciences Institute, University of Washington, Seattle, WA98195
| | - Cholpisit Kiattisewee
- Center for Synthetic Biology, University of Washington, Seattle, WA98195
- Molecular Engineering & Sciences Institute, University of Washington, Seattle, WA98195
| | - Cassandra J. Maranas
- Center for Synthetic Biology, University of Washington, Seattle, WA98195
- Molecular Engineering & Sciences Institute, University of Washington, Seattle, WA98195
| | - Jesse G. Zalatan
- Center for Synthetic Biology, University of Washington, Seattle, WA98195
- Molecular Engineering & Sciences Institute, University of Washington, Seattle, WA98195
- Department of Chemistry, University of Washington, Seattle, WA98195
| | - James M. Carothers
- Department of Chemical Engineering, University of Washington, Seattle, WA98195
- Center for Synthetic Biology, University of Washington, Seattle, WA98195
- Molecular Engineering & Sciences Institute, University of Washington, Seattle, WA98195
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2
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Karaman E, Eyüpoğlu AE, Mahmoudi Azar L, Uysal S. Large-Scale Production of Anti-RNase A VHH Expressed in pyrG Auxotrophic Aspergillus oryzae. Curr Issues Mol Biol 2023; 45:4778-4795. [PMID: 37367053 DOI: 10.3390/cimb45060304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 05/15/2023] [Accepted: 05/18/2023] [Indexed: 06/28/2023] Open
Abstract
Nanobodies, also referred to as VHH antibodies, are the smallest fragments of naturally produced camelid antibodies and are ideal affinity reagents due to their remarkable properties. They are considered an alternative to monoclonal antibodies (mAbs) with potential utility in imaging, diagnostic, and other biotechnological applications given the difficulties associated with mAb expression. Aspergillus oryzae (A. oryzae) is a potential system for the large-scale expression and production of functional VHH antibodies that can be used to meet the demand for affinity reagents. In this study, anti-RNase A VHH was expressed under the control of the glucoamylase promoter in pyrG auxotrophic A. oryzae grown in a fermenter. The feature of pyrG auxotrophy, selected for the construction of a stable and efficient platform, was established using homologous recombination. Pull-down assay, size exclusion chromatography, and surface plasmon resonance were used to confirm the binding specificity of anti-RNase A VHH to RNase A. The affinity of anti-RNase A VHH was nearly 18.3-fold higher (1.9 nM) when expressed in pyrG auxotrophic A. oryzae rather than in Escherichia coli. This demonstrates that pyrG auxotrophic A. oryzae is a practical, industrially scalable, and promising biotechnological platform for the large-scale production of functional VHH antibodies with high binding activity.
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Affiliation(s)
- Elif Karaman
- Beykoz Institute of Life Sciences and Biotechnology, Bezmialem Vakif University, 34820 Istanbul, Turkey
- Department of Biotechnology, Institute of Health Sciences, Bezmialem Vakif University, 34093 Istanbul, Turkey
| | - Alp Ertunga Eyüpoğlu
- Department of Molecular Biology and Genetics, Faculty of Arts and Sciences, Bogazici University, 34450 Istanbul, Turkey
| | - Lena Mahmoudi Azar
- Beykoz Institute of Life Sciences and Biotechnology, Bezmialem Vakif University, 34820 Istanbul, Turkey
| | - Serdar Uysal
- Beykoz Institute of Life Sciences and Biotechnology, Bezmialem Vakif University, 34820 Istanbul, Turkey
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3
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Nicoleti JL, Braga ES, Stanisic D, Jadranin M, Façanha DAE, Barral TD, Hanna SA, Azevedo V, Meyer R, Tasic L, Portela RW. A serum NMR metabolomic analysis of the Corynebacterium pseudotuberculosis infection in goats. Appl Microbiol Biotechnol 2023:10.1007/s00253-023-12595-0. [PMID: 37219572 DOI: 10.1007/s00253-023-12595-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2023] [Revised: 05/10/2023] [Accepted: 05/15/2023] [Indexed: 05/24/2023]
Abstract
Caseous lymphadenitis (CLA), an infectious disease caused by Corynebacterium pseudotuberculosis in small ruminants, is highly prevalent worldwide. Economic losses have already been associated with the disease, and little is known about the host-pathogen relationship associated with the disease. The present study aimed to perform a metabolomic study of the C. pseudotuberculosis infection in goats. Serum samples were collected from a herd of 173 goats. The animals were classified as controls (not infected), asymptomatic (seropositives but without detectable CLA clinical signs), and symptomatic (seropositive animals presenting CLA lesions), according to microbiological isolation and immunodiagnosis. The serum samples were analyzed using nuclear magnetic resonance (1H-NMR), nuclear Overhauser effect spectroscopy (NOESY), and Carr-Purcell-Meiboom-Gill (CPMG) sequences. The NMR data were analyzed using chemometrics, and principal component analysis (PCA) and partial least square discriminant analysis (PLS-DA) were performed to discover specific biomarkers responsible for discrimination between the groups. A high dissemination of the infection by C. pseudotuberculosis was observed, being 74.57% asymptomatic and 11.56% symptomatic. In the evaluation of 62 serum samples by NMR, the techniques were satisfactory in the discrimination of the groups, being also complementary and mutually confirming, demonstrating possible biomarkers for the infection by the bacterium. Twenty metabolites of interest were identified by NOESY and 29 by CPMG, such as tryptophan, polyunsaturated fatty acids, formic acid, NAD+, and 3-hydroxybutyrate, opening promising possibilities for the use of these results in new therapeutic, immunodiagnosis, and immunoprophylactic tools, as well as for studies of the immune response against C. pseudotuberculosis. KEY POINTS: • Sixty-two samples from healthy, CLA asymptomatic, and symptomatic goats were screened • Twenty metabolites of interest were identified by NOESY and 29 by CPMG • 1H-NMR NOESY and CPMG were complementary and mutually confirming.
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Affiliation(s)
- Jorge Luis Nicoleti
- Laboratório de Imunologia E Biologia Molecular, Instituto de Ciências da Saúde, Universidade Federal da Bahia, Salvador, Bahia State, 40231-300, Brazil
| | - Erik Sobrinho Braga
- Laboratório de Química Biológica, Instituto de Química, Universidade Estadual de Campinas, Campinas, São Paulo State, 13083-970, Brazil
| | - Danijela Stanisic
- Laboratório de Química Biológica, Instituto de Química, Universidade Estadual de Campinas, Campinas, São Paulo State, 13083-970, Brazil
| | - Milka Jadranin
- Laboratório de Química Biológica, Instituto de Química, Universidade Estadual de Campinas, Campinas, São Paulo State, 13083-970, Brazil
- Institute of Chemistry, Technology and Metallurgy, University of Belgrade, 11000, Belgrade, Serbia
| | - Débora Andréa Evangelista Façanha
- Institute of Rural Development, Universidade da Integração Internacional da Lusofonia Afro-Brasileira, Redenção, Ceará State, 62790-000, Brazil
| | - Thiago Doria Barral
- Laboratório de Imunologia E Biologia Molecular, Instituto de Ciências da Saúde, Universidade Federal da Bahia, Salvador, Bahia State, 40231-300, Brazil
| | - Samira Abdallah Hanna
- Laboratório de Imunologia E Biologia Molecular, Instituto de Ciências da Saúde, Universidade Federal da Bahia, Salvador, Bahia State, 40231-300, Brazil
| | - Vasco Azevedo
- Laboratório de Genética Celular e Molecular, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais State, 31270-901, Brazil
| | - Roberto Meyer
- Laboratório de Imunologia E Biologia Molecular, Instituto de Ciências da Saúde, Universidade Federal da Bahia, Salvador, Bahia State, 40231-300, Brazil
| | - Ljubica Tasic
- Laboratório de Química Biológica, Instituto de Química, Universidade Estadual de Campinas, Campinas, São Paulo State, 13083-970, Brazil
| | - Ricardo Wagner Portela
- Laboratório de Imunologia E Biologia Molecular, Instituto de Ciências da Saúde, Universidade Federal da Bahia, Salvador, Bahia State, 40231-300, Brazil.
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4
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Xue C, Ng IS. A direct enzymatic evaluation platform (DEEP) to fine-tuning pyridoxal 5'-phosphate-dependent proteins for cadaverine production. Biotechnol Bioeng 2023; 120:272-283. [PMID: 36271696 DOI: 10.1002/bit.28270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 10/06/2022] [Accepted: 10/17/2022] [Indexed: 11/11/2022]
Abstract
Pyridoxal 5'-phosphate (pyridoxal phosphate, PLP) is an essential cofactor for multiple enzymatic reactions in industry. However, cofactor engineering based on PLP regeneration and related to the performance of enzymes in chemical production has rarely been discussed. First, we found that MG1655 strain was sensitive to nitrogen source and relied on different amino acids, thus the biomass was significantly reduced when PLP excess in the medium. Then, the six KEIO collection strains were applied to find out the prominent gene in deoxyxylulose-5-phosphate (DXP) pathway, where pdxB was superior in controlling cell growth. Therefore, the clustered regularly interspaced short palindromic repeats interference (CRISPRi) targeted on pdxB in MG1655 was employed to establish a novel direct enzymatic evaluation platform (DEEP) as a high-throughput tool and obtained the optimal modules for incorporating of PLP to enhance the biomass and activity of PLP-dependent enzymes simultaneously. As a result, the biomass has increased by 55% using PlacI promoter driven pyridoxine 5'-phosphate oxidase (PdxH) with a trace amount of precursor. When the strains incorporated DEEP and lysine decarboxylase (CadA), the cadaverine productivity was increased 32% due to the higher expression of CadA. DEEP is not only feasible for high-throughput screening of the best chassis for PLP engineering but also practical in fine-tuning the quantity and quality of enzymes.
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Affiliation(s)
- Chengfeng Xue
- Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan
| | - I-Son Ng
- Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan
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5
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Gupta M, Wong M, Jawed K, Gedeon K, Barrett H, Bassalo M, Morrison C, Eqbal D, Yazdani SS, Gill RT, Huang J, Douaisi M, Dordick J, Belfort G, Koffas MA. Isobutanol production by combined in vivo and in vitro metabolic engineering. Metab Eng Commun 2022; 15:e00210. [PMID: 36325486 PMCID: PMC9619177 DOI: 10.1016/j.mec.2022.e00210] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 10/03/2022] [Accepted: 10/16/2022] [Indexed: 12/12/2022] Open
Abstract
The production of the biofuel, isobutanol, in E. coli faces limitations due to alcohol toxicity, product inhibition, product recovery, and long-term industrial feasibility. Here we demonstrate an approach of combining both in vivo with in vitro metabolic engineering to produce isobutanol. The in vivo production of α-ketoisovalerate (KIV) was conducted through CRISPR mediated integration of the KIV pathway in bicistronic design (BCD) in E. coli and inhibition of competitive valine pathway using CRISPRi technology. The subsequent in vitro conversion to isobutanol was carried out with engineered enzymes for 2-ketoacid decarboxylase (KIVD) and alcohol dehydrogenase (ADH). For the in vivo production of KIV and subsequent in vitro production of isobutanol, this two-step serial approach resulted in yields of 56% and 93%, productivities of 0.62 and 0.074 g L-1 h-1, and titers of 5.6 and 1.78 g L-1, respectively. Thus, this combined biosynthetic system can be used as a modular approach for producing important metabolites, like isobutanol, without the limitations associated with in vivo production using a consolidated bioprocess.
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Affiliation(s)
- Mamta Gupta
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA,Department of Botany and Environmental Studies, DAV University, Jalandhar, 144 001, Punjab, India
| | - Matthew Wong
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Kamran Jawed
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA,DBT-ICGEB Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
| | - Kamil Gedeon
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Hannah Barrett
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Marcelo Bassalo
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, CO, 80309, USA
| | - Clifford Morrison
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Danish Eqbal
- DBT-ICGEB Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
| | - Syed Shams Yazdani
- DBT-ICGEB Advanced Bioenergy Research, International Centre for Genetic Engineering and Biotechnology, New Delhi, 110067, India
| | - Ryan T. Gill
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, CO, 80309, USA
| | - Jiaqi Huang
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Marc Douaisi
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Jonathan Dordick
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Georges Belfort
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Mattheos A.G. Koffas
- Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA,Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA,Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA,Corresponding author. Howard P. Isermann Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY, 12180, USA.
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6
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Kasari M, Kasari V, Kärmas M, Jõers A. Decoupling Growth and Production by Removing the Origin of Replication from a Bacterial Chromosome. ACS Synth Biol 2022; 11:2610-2622. [PMID: 35798328 DOI: 10.1021/acssynbio.1c00618] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Efficient production of biochemicals and proteins in cell factories frequently benefits from a two-stage bioprocess in which growth and production phases are decoupled. Here, we describe a novel growth switch based on the permanent removal of the origin of replication (oriC) from the Escherichia coli chromosome. Without oriC, cells cannot initiate a new round of replication, and they stop growing while their metabolism remains active. Our system relies on a serine recombinase from bacteriophage phiC31 whose expression is controlled by the temperature-sensitive cI857 repressor from phage lambda. The reporter protein expression in switched cells continues after cessation of growth, leading to protein levels up to 5 times higher compared to nonswitching cells. Switching induces a unique physiological state that is different from both normal exponential and stationary phases. The switched cells remain in this state even when not growing, retain their protein synthesis capacity, and do not induce proteins associated with the stationary phase. Our switcher technology is potentially useful for a range of products and applicable in many bacterial species for decoupling growth and production.
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Affiliation(s)
- Marje Kasari
- Institute of Technology, University of Tartu, Nooruse 1, 50104 Tartu, Estonia
| | - Villu Kasari
- Institute of Technology, University of Tartu, Nooruse 1, 50104 Tartu, Estonia
| | - Mirjam Kärmas
- Institute of Technology, University of Tartu, Nooruse 1, 50104 Tartu, Estonia
| | - Arvi Jõers
- Institute of Technology, University of Tartu, Nooruse 1, 50104 Tartu, Estonia
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7
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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.
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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.
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8
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Dolgalev G, Poverennaya E. Applications of CRISPR-Cas Technologies to Proteomics. Genes (Basel) 2021; 12:1790. [PMID: 34828396 PMCID: PMC8625504 DOI: 10.3390/genes12111790] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 11/10/2021] [Accepted: 11/11/2021] [Indexed: 12/12/2022] Open
Abstract
CRISPR-Cas-based genome editing is a revolutionary approach that has provided an unprecedented investigational power for the life sciences. Rapid and efficient, CRISPR-Cas technologies facilitate the generation of complex biological models and at the same time provide the necessary methods required to study these models in depth. The field of proteomics has already significantly benefited from leveraging the power of CRISPR-Cas technologies, however, many potential applications of these technologies in the context of proteomics remain unexplored. In this review, we intend to provide an introduction to the CRISPR-Cas technologies and demonstrate how they can be applied to solving proteome-centric questions. To achieve this goal, we begin with the description of the modern suite of CRISPR-Cas-based tools, focusing on the more mature CRISPR-Cas9 system. In the second part of this review, we highlight both established and potential applications of the CRISPR-Cas technologies to proteomics.
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9
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Shabestary K, Hernández HP, Miao R, Ljungqvist E, Hallman O, Sporre E, Branco Dos Santos F, Hudson EP. Cycling between growth and production phases increases cyanobacteria bioproduction of lactate. Metab Eng 2021; 68:131-141. [PMID: 34601120 DOI: 10.1016/j.ymben.2021.09.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 09/03/2021] [Accepted: 09/25/2021] [Indexed: 01/23/2023]
Abstract
Decoupling growth from product synthesis is a promising strategy to increase carbon partitioning and maximize productivity in cell factories. However, reduction in both substrate uptake rate and metabolic activity in the production phase are an underlying problem for upscaling. Here, we used CRISPR interference to repress growth in lactate-producing Synechocystis sp. PCC 6803. Carbon partitioning to lactate in the production phase exceeded 90%, but CO2 uptake was severely reduced compared to uptake during the growth phase. We characterized strains during the onset of growth arrest using transcriptomics and proteomics. Multiple genes involved in ATP homeostasis were regulated once growth was inhibited, which suggests an alteration of energy charge that may lead to reduced substrate uptake. In order to overcome the reduced metabolic activity and take advantage of increased carbon partitioning, we tested a novel production strategy that involved alternating growth arrest and recovery by periodic addition of an inducer molecule to activate CRISPRi. Using this strategy, we maintained lactate biosynthesis in Synechocystis for 30 days in a constant light turbidostat cultivation. Cumulative lactate titers were also increased by 100% compared to a constant growth-arrest regime, and reached 1 g/L. Further, the cultivation produced lactate for 30 days, compared to 20 days for the non-growth arrest cultivation. Periodic growth arrest could be applicable for other products, and in cyanobacteria, could be linked to internal circadian rhythms that persist in constant light.
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Affiliation(s)
- Kiyan Shabestary
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH - Royal Institute of Technology, Stockholm, Sweden
| | - Hugo Pineda Hernández
- Molecular Microbial Physiology Group, Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH, the Netherlands
| | - Rui Miao
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH - Royal Institute of Technology, Stockholm, Sweden
| | - Emil Ljungqvist
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH - Royal Institute of Technology, Stockholm, Sweden
| | - Olivia Hallman
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH - Royal Institute of Technology, Stockholm, Sweden
| | - Emil Sporre
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH - Royal Institute of Technology, Stockholm, Sweden
| | - Filipe Branco Dos Santos
- Molecular Microbial Physiology Group, Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, Science Park 904, Amsterdam, 1098 XH, the Netherlands
| | - Elton P Hudson
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Science for Life Laboratory, KTH - Royal Institute of Technology, Stockholm, Sweden.
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