1
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Liu Y, Liang Z, Yu S, Ye Y, Lin Z. CRISPR RNA-Guided Transposases Facilitate Dispensable Gene Study in Phage. Viruses 2024; 16:422. [PMID: 38543787 PMCID: PMC10974960 DOI: 10.3390/v16030422] [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: 01/26/2024] [Revised: 03/05/2024] [Accepted: 03/07/2024] [Indexed: 05/23/2024] Open
Abstract
Phages provide a potential therapy for multi-drug-resistant (MDR) bacteria. However, a significant portion of viral genes often remains unknown, posing potential dangers. The identification of non-essential genes helps dissect and simplify phage genomes, but current methods have various limitations. In this study, we present an in vivo two-plasmid transposon insertion system to assess the importance of phage genes, which is based on the V. cholerae transposon Tn6677, encoding a nuclease-deficient type I-F CRISPR-Cas system. We first validated the system in Pseudomonas aeruginosa PAO1 and its phage S1. We then used the selection marker AcrVA1 to protect transposon-inserted phages from CRISPR-Cas12a and enriched the transposon-inserted phages. For a pool of selected 10 open-reading frames (2 known functional protein genes and 8 hypothetical protein genes) of phage S1, we identified 5 (2 known functional protein genes and 3 hypothetical protein genes) as indispensable genes and the remaining 5 (all hypothetical protein genes) as dispensable genes. This approach offers a convenient, site-specific method that does not depend on homologous arms and double-strand breaks (DSBs), holding promise for future applications across a broader range of phages and facilitating the identification of the importance of phage genes and the insertion of genetic cargos.
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Affiliation(s)
- Yanmei Liu
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China; (Y.L.); (Z.L.); (S.Y.)
| | - Zizhen Liang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China; (Y.L.); (Z.L.); (S.Y.)
| | - Shuting Yu
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China; (Y.L.); (Z.L.); (S.Y.)
| | - Yanrui Ye
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China; (Y.L.); (Z.L.); (S.Y.)
| | - Zhanglin Lin
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China; (Y.L.); (Z.L.); (S.Y.)
- Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
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2
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Costa AR, Azeredo J, Pires DP. Synthetic Biology to Engineer Bacteriophage Genomes. Methods Mol Biol 2024; 2734:261-277. [PMID: 38066375 DOI: 10.1007/978-1-0716-3523-0_17] [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: 12/18/2023]
Abstract
Recent advances in the synthetic biology field have enabled the development of new molecular biology techniques used to build specialized bacteriophages with new functionalities. Bacteriophages have been engineered toward a wide range of applications, including pathogen control and detection, targeted drug delivery, or even assembly of new materials.In this chapter, two strategies that have been successfully used to genetically engineer bacteriophage genomes will be addressed: the bacteriophage recombineering of electroporated DNA (BRED) and the yeast-based phage-engineering platform.
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Affiliation(s)
- Ana Rita Costa
- Department of Bionanoscience, Delft University of Technology, Delft, the Netherlands
| | - Joana Azeredo
- CEB - Centre of Biological Engineering, University of Minho, Braga, Portugal
- LABBELS - Associate Laboratory, Braga, Guimarães, Portugal
| | - Diana Priscila Pires
- CEB - Centre of Biological Engineering, University of Minho, Braga, Portugal.
- LABBELS - Associate Laboratory, Braga, Guimarães, Portugal.
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3
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Skutel M, Andriianov A, Zavialova M, Kirsanova M, Shodunke O, Zorin E, Golovshchinskii A, Severinov K, Isaev A. T5-like phage BF23 evades host-mediated DNA restriction and methylation. MICROLIFE 2023; 4:uqad044. [PMID: 38025991 PMCID: PMC10644984 DOI: 10.1093/femsml/uqad044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 10/15/2023] [Accepted: 10/25/2023] [Indexed: 12/01/2023]
Abstract
Bacteriophage BF23 is a close relative of phage T5, a prototypical Tequintavirus that infects Escherichia coli. BF23 was isolated in the middle of the XXth century and was extensively studied as a model object. Like T5, BF23 carries long ∼9.7 kb terminal repeats, injects its genome into infected cell in a two-stage process, and carries multiple specific nicks in its double-stranded genomic DNA. The two phages rely on different host secondary receptors-FhuA (T5) and BtuB (BF23). Only short fragments of the BF23 genome, including the region encoding receptor interacting proteins, have been determined. Here, we report the full genomic sequence of BF23 and describe the protein content of its virion. T5-like phages represent a unique group that resist restriction by most nuclease-based host immunity systems. We show that BF23, like other Tequintavirus phages, resist Types I/II/III restriction-modification host immunity systems if their recognition sites are located outside the terminal repeats. We also demonstrate that the BF23 avoids host-mediated methylation. We propose that inhibition of methylation is a common feature of Tequintavirus and Epseptimavirus genera phages, that is not, however, associated with their antirestriction activity.
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Affiliation(s)
- Mikhail Skutel
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30/1, 143028, Moscow, Russia
| | - Aleksandr Andriianov
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30/1, 143028, Moscow, Russia
| | - Maria Zavialova
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30/1, 143028, Moscow, Russia
- Institute of Biomedical Chemistry (IBMC), Pogodinskaya 10/8, 119435, Moscow, Russia
| | - Maria Kirsanova
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30/1, 143028, Moscow, Russia
| | - Oluwasefunmi Shodunke
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30/1, 143028, Moscow, Russia
- Moscow Institute of Physics and Technology, Institutskiy Pereulok 9, 141701, Dolgoprudny, Russia
| | - Evgenii Zorin
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30/1, 143028, Moscow, Russia
| | | | - Konstantin Severinov
- Waksman Institute of Microbiology, 190 Frelinghuysen Rd, NJ 08854, Piscataway, United States
| | - Artem Isaev
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30/1, 143028, Moscow, Russia
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4
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Lv S, Wang Y, Jiang K, Guo X, Zhang J, Zhou F, Li Q, Jiang Y, Yang C, Teng T. Genetic Engineering and Biosynthesis Technology: Keys to Unlocking the Chains of Phage Therapy. Viruses 2023; 15:1736. [PMID: 37632078 PMCID: PMC10457950 DOI: 10.3390/v15081736] [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: 06/26/2023] [Revised: 07/21/2023] [Accepted: 08/12/2023] [Indexed: 08/27/2023] Open
Abstract
Phages possess the ability to selectively eliminate pathogenic bacteria by recognizing bacterial surface receptors. Since their discovery, phages have been recognized for their potent bactericidal properties, making them a promising alternative to antibiotics in the context of rising antibiotic resistance. However, the rapid emergence of phage-resistant strains (generally involving temperature phage) and the limited host range of most phage strains have hindered their antibacterial efficacy, impeding their full potential. In recent years, advancements in genetic engineering and biosynthesis technology have facilitated the precise engineering of phages, thereby unleashing their potential as a novel source of antibacterial agents. In this review, we present a comprehensive overview of the diverse strategies employed for phage genetic engineering, as well as discuss their benefits and drawbacks in terms of bactericidal effect.
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Affiliation(s)
- Sixuan Lv
- School of Nursing and Health, Henan University, Kaifeng 475004, China
- Institute of Biomedical Informatics, School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
| | - Yuhan Wang
- Institute of Biomedical Informatics, School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
| | - Kaixin Jiang
- School of Nursing and Health, Henan University, Kaifeng 475004, China
- Institute of Biomedical Informatics, School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
| | - Xinge Guo
- School of Nursing and Health, Henan University, Kaifeng 475004, China
- Institute of Biomedical Informatics, School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
| | - Jing Zhang
- School of Nursing and Health, Henan University, Kaifeng 475004, China
- Institute of Biomedical Informatics, School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
| | - Fang Zhou
- School of Nursing and Health, Henan University, Kaifeng 475004, China
- Institute of Biomedical Informatics, School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
| | - Qiming Li
- School of Nursing and Health, Henan University, Kaifeng 475004, China
- Institute of Biomedical Informatics, School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
| | - Yuan Jiang
- Institute of Biomedical Informatics, School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
| | - Changyong Yang
- School of Nursing and Health, Henan University, Kaifeng 475004, China
| | - Tieshan Teng
- School of Nursing and Health, Henan University, Kaifeng 475004, China
- Institute of Biomedical Informatics, School of Basic Medical Sciences, Henan University, Kaifeng 475004, China
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5
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Esteves NC, Bigham DN, Scharf BE. Phages on filaments: A genetic screen elucidates the complex interactions between Salmonella enterica flagellin and bacteriophage Chi. PLoS Pathog 2023; 19:e1011537. [PMID: 37535496 PMCID: PMC10399903 DOI: 10.1371/journal.ppat.1011537] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 07/04/2023] [Indexed: 08/05/2023] Open
Abstract
The bacterial flagellum is a rotary motor organelle and important virulence factor that propels motile pathogenic bacteria, such as Salmonella enterica, through their surroundings. Bacteriophages, or phages, are viruses that solely infect bacteria. As such, phages have myriad applications in the healthcare field, including phage therapy against antibiotic-resistant bacterial pathogens. Bacteriophage χ (Chi) is a flagellum-dependent (flagellotropic) bacteriophage, which begins its infection cycle by attaching its long tail fiber to the S. enterica flagellar filament as its primary receptor. The interactions between phage and flagellum are poorly understood, as are the reasons that χ only kills certain Salmonella serotypes while others entirely evade phage infection. In this study, we used molecular cloning, targeted mutagenesis, heterologous flagellin expression, and phage-host interaction assays to determine which domains within the flagellar filament protein flagellin mediate this complex interaction. We identified the antigenic N- and C-terminal D2 domains as essential for phage χ binding, with the hypervariable central D3 domain playing a less crucial role. Here, we report that the primary structure of the Salmonella flagellin D2 domains is the major determinant of χ adhesion. The phage susceptibility of a strain is directly tied to these domains. We additionally uncovered important information about flagellar function. The central and most variable domain, D3, is not required for motility in S. Typhimurium 14028s, as it can be deleted or its sequence composition can be significantly altered with minimal impacts on motility. Further knowledge about the complex interactions between flagellotropic phage χ and its primary bacterial receptor may allow genetic engineering of its host range for use as targeted antimicrobial therapy against motile pathogens of the χ-host genera Salmonella, Escherichia, or Serratia.
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Affiliation(s)
- Nathaniel C. Esteves
- Dept. of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
| | - Danielle N. Bigham
- Dept. of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
| | - Birgit E. Scharf
- Dept. of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, United States of America
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6
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Usman SS, Uba AI, Christina E. Bacteriophage genome engineering for phage therapy to combat bacterial antimicrobial resistance as an alternative to antibiotics. Mol Biol Rep 2023; 50:7055-7067. [PMID: 37392288 DOI: 10.1007/s11033-023-08557-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 05/30/2023] [Indexed: 07/03/2023]
Abstract
Bacteriophages (phages) are viruses that mainly infect bacteria and are ubiquitously distributed in nature, especially to their host. Phage engineering involves nucleic acids manipulation of phage genome for antimicrobial activity directed against pathogens through the applications of molecular biology techniques such as synthetic biology methods, homologous recombination, CRISPY-BRED and CRISPY-BRIP recombineering, rebooting phage-based engineering, and targeted nucleases including CRISPR/Cas9, zinc-finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs). Management of bacteria is widely achieved using antibiotics whose mechanism of action has been shown to target both the genetic dogma and the metabolism of pathogens. However, the overuse of antibiotics has caused the emergence of multidrug-resistant (MDR) bacteria which account for nearly 5 million deaths as of 2019 thereby posing threats to the public health sector, particularly by 2050. Lytic phages have drawn attention as a strong alternative to antibiotics owing to the promising efficacy and safety of phage therapy in various models in vivo and human studies. Therefore, harnessing phage genome engineering methods, particularly CRISPR/Cas9 to overcome the limitations such as phage narrow host range, phage resistance or any potential eukaryotic immune response for phage-based enzymes/proteins therapy may designate phage therapy as a strong alternative to antibiotics for combatting bacterial antimicrobial resistance (AMR). Here, the current trends and progress in phage genome engineering techniques and phage therapy are reviewed.
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Affiliation(s)
- Sani Sharif Usman
- Department of Molecular Biology and Genetic Engineering, School of Bioengineering and Biosciences, Lovely Professional University, Jalandhar-Delhi G.T. Road, Phagwara, 144401, Punjab, India
- Department of Biological Sciences, Faculty of Science, Federal University of Kashere, P.M.B. 0182, Gombe, Nigeria
| | - Abdullahi Ibrahim Uba
- Department of Molecular Biology and Genetics, Istanbul AREL University, 34537, Istanbul, Türkiye
| | - Evangeline Christina
- Department of Molecular Biology and Genetic Engineering, School of Bioengineering and Biosciences, Lovely Professional University, Jalandhar-Delhi G.T. Road, Phagwara, 144401, Punjab, India.
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7
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Paul SS. Phage engineering for development of diagnostic tools. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2023; 200:91-101. [PMID: 37739561 DOI: 10.1016/bs.pmbts.2023.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/24/2023]
Abstract
The bacteriophages rely on the host cell to provide energy and resources for their own replication. Antibody-based diagnostic tests rely on the antibody and the biomarker interactions. Since, most of these diagnostic tools employ the use of antibodies; hence, they require intensive storage protocols at cold conditions and incur high time and capital cost due to their production and purification process. Phage-based diagnostics can overcome this limitation. Bacteriophages, have been used as emerging tools for the detection of various pathogens. Rapid phage-mediated detection assays have become commercial diagnostic tools. Conventional method and new cloning approaches have been followed to specifically detect a disease- causing microbial strains. This review discusses use of Phage typing as diagnostic tools, phage-based detection methods, and their usage for signal amplification. Design rules for reporter phage engineering are also discussed followed by different engineering platforms for phage genome editing. We also discuss recent examples of how phage research is influencing the recent advances in the development of phage-based diagnostics for ultra-sensitive detection of various bio-species, outlining the advantages and limitations of detection technology of phage-based assays.
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8
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Jia HJ, Jia PP, Yin S, Bu LK, Yang G, Pei DS. Engineering bacteriophages for enhanced host range and efficacy: insights from bacteriophage-bacteria interactions. Front Microbiol 2023; 14:1172635. [PMID: 37323893 PMCID: PMC10264812 DOI: 10.3389/fmicb.2023.1172635] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 05/10/2023] [Indexed: 06/17/2023] Open
Abstract
Bacteriophages, the most abundant organisms on earth, have the potential to address the rise of multidrug-resistant bacteria resulting from the overuse of antibiotics. However, their high specificity and limited host range can hinder their effectiveness. Phage engineering, through the use of gene editing techniques, offers a means to enhance the host range of bacteria, improve phage efficacy, and facilitate efficient cell-free production of phage drugs. To engineer phages effectively, it is necessary to understand the interaction between phages and host bacteria. Understanding the interaction between the receptor recognition protein of bacteriophages and host receptors can serve as a valuable guide for modifying or replacing these proteins, thereby altering the receptor range of the bacteriophage. Research and development focused on the CRISPR-Cas bacterial immune system against bacteriophage nucleic acids can provide the necessary tools to promote recombination and counter-selection in engineered bacteriophage programs. Additionally, studying the transcription and assembly functions of bacteriophages in host bacteria can facilitate the engineered assembly of bacteriophage genomes in non-host environments. This review highlights a comprehensive summary of phage engineering methods, including in-host and out-of-host engineering, and the use of high-throughput methods to understand their role. The main aim of these techniques is to harness the intricate interactions between bacteriophages and hosts to inform and guide the engineering of bacteriophages, particularly in the context of studying and manipulating the host range of bacteriophages. By employing advanced high-throughput methods to identify specific bacteriophage receptor recognition genes, and subsequently introducing modifications or performing gene swapping through in-host recombination or out-of-host synthesis, it becomes possible to strategically alter the host range of bacteriophages. This capability holds immense significance for leveraging bacteriophages as a promising therapeutic approach against antibiotic-resistant bacteria.
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Affiliation(s)
- Huang-Jie Jia
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, China
| | - Pan-Pan Jia
- School of Public Health, Chongqing Medical University, Chongqing, China
| | - Supei Yin
- Urinary Nephropathy Center, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Ling-Kang Bu
- College of Life Science, Henan Normal University, Xinxiang, China
| | - Guan Yang
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, China
| | - De-Sheng Pei
- School of Public Health, Chongqing Medical University, Chongqing, China
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9
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Hussain W, Yang X, Ullah M, Wang H, Aziz A, Xu F, Asif M, Ullah MW, Wang S. Genetic engineering of bacteriophages: Key concepts, strategies, and applications. Biotechnol Adv 2023; 64:108116. [PMID: 36773707 DOI: 10.1016/j.biotechadv.2023.108116] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 02/03/2023] [Accepted: 02/05/2023] [Indexed: 02/12/2023]
Abstract
Bacteriophages are the most abundant biological entity in the world and hold a tremendous amount of unexplored genetic information. Since their discovery, phages have drawn a great deal of attention from researchers despite their small size. The development of advanced strategies to modify their genomes and produce engineered phages with desired traits has opened new avenues for their applications. This review presents advanced strategies for developing engineered phages and their potential antibacterial applications in phage therapy, disruption of biofilm, delivery of antimicrobials, use of endolysin as an antibacterial agent, and altering the phage host range. Similarly, engineered phages find applications in eukaryotes as a shuttle for delivering genes and drugs to the targeted cells, and are used in the development of vaccines and facilitating tissue engineering. The use of phage display-based specific peptides for vaccine development, diagnostic tools, and targeted drug delivery is also discussed in this review. The engineered phage-mediated industrial food processing and biocontrol, advanced wastewater treatment, phage-based nano-medicines, and their use as a bio-recognition element for the detection of bacterial pathogens are also part of this review. The genetic engineering approaches hold great potential to accelerate translational phages and research. Overall, this review provides a deep understanding of the ingenious knowledge of phage engineering to move them beyond their innate ability for potential applications.
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Affiliation(s)
- Wajid Hussain
- Advanced Biomaterials & Tissues Engineering Center, College of Life Sciences and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Xiaohan Yang
- Advanced Biomaterials & Tissues Engineering Center, College of Life Sciences and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Mati Ullah
- Department of Biotechnology, College of Life Sciences and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Huan Wang
- Advanced Biomaterials & Tissues Engineering Center, College of Life Sciences and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Ayesha Aziz
- Advanced Biomaterials & Tissues Engineering Center, College of Life Sciences and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Fang Xu
- Huazhong University of Science and Technology Hospital, Wuhan 430074, China
| | - Muhammad Asif
- Hubei Key Laboratory of Plasma Chemistry and Advanced Materials, School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan 430205, China
| | - Muhammad Wajid Ullah
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, China.
| | - Shenqi Wang
- Advanced Biomaterials & Tissues Engineering Center, College of Life Sciences and Technology, Huazhong University of Science and Technology, Wuhan 430074, China.
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10
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Fishman CB, Crawford KD, Bhattarai-Kline S, Zhang K, González-Delgado A, Shipman SL. Continuous Multiplexed Phage Genome Editing Using Recombitrons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.24.534024. [PMID: 36993281 PMCID: PMC10055335 DOI: 10.1101/2023.03.24.534024] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Bacteriophages, which naturally shape bacterial communities, can be co-opted as a biological technology to help eliminate pathogenic bacteria from our bodies and food supply1. Phage genome editing is a critical tool to engineer more effective phage technologies. However, editing phage genomes has traditionally been a low efficiency process that requires laborious screening, counter selection, or in vitro construction of modified genomes2. These requirements impose limitations on the type and throughput of phage modifications, which in turn limit our knowledge and potential for innovation. Here, we present a scalable approach for engineering phage genomes using recombitrons: modified bacterial retrons3 that generate recombineering donor DNA paired with single stranded binding and annealing proteins to integrate those donors into phage genomes. This system can efficiently create genome modifications in multiple phages without the need for counterselection. Moreover, the process is continuous, with edits accumulating in the phage genome the longer the phage is cultured with the host, and multiplexable, with different editing hosts contributing distinct mutations along the genome of a phage in a mixed culture. In lambda phage, as an example, recombitrons yield single-base substitutions at up to 99% efficiency and up to 5 distinct mutations installed on a single phage genome, all without counterselection and only a few hours of hands-on time.
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Affiliation(s)
- Chloe B. Fishman
- Gladstone Institute of Data Science and Biotechnology, San Francisco, CA, USA
| | - Kate D. Crawford
- Gladstone Institute of Data Science and Biotechnology, San Francisco, CA, USA
- Graduate Program in Bioengineering, University of California, San Francisco and Berkeley, CA, USA
| | - Santi Bhattarai-Kline
- Gladstone Institute of Data Science and Biotechnology, San Francisco, CA, USA
- UCLA-Caltech Medical Scientist Training Program, David Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Karen Zhang
- Gladstone Institute of Data Science and Biotechnology, San Francisco, CA, USA
- Graduate Program in Bioengineering, University of California, San Francisco and Berkeley, CA, USA
| | | | - Seth L. Shipman
- Gladstone Institute of Data Science and Biotechnology, San Francisco, CA, USA
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA
- Chan Zuckerberg Biohub, San Francisco, CA
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11
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Huss P, Chen J, Raman S. High-throughput approaches to understand and engineer bacteriophages. Trends Biochem Sci 2023; 48:187-197. [PMID: 36180320 PMCID: PMC9868059 DOI: 10.1016/j.tibs.2022.08.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 08/30/2022] [Accepted: 08/31/2022] [Indexed: 01/26/2023]
Abstract
Bacteriophage research has been vital to fundamental aspects of modern biology. Advances in metagenomics have revealed treasure troves of new and uncharacterized bacteriophages ('phages') that are not yet understood. However, our ability to find new phages has outpaced our understanding of how sequence encodes function in phages. Traditional approaches for characterizing phages are limited in scale and face hurdles in determining how changes in sequence drive function. We describe powerful emerging technologies that can be used to clarify sequence-function relationships in phages through high-throughput genome engineering. Using these approaches, up to 105 variants can be characterized through pooled selection experiments and deep sequencing. We describe caveats when using these tools and provide examples of basic science and engineering goals that are pursuable using these approaches.
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Affiliation(s)
- Phil Huss
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA; Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Jackie Chen
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Srivatsan Raman
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA; Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA.
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12
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Goren MG, Mahata T, Qimron U. An efficient, scarless, selection-free technology for phage engineering. RNA Biol 2023; 20:830-835. [PMID: 37846029 PMCID: PMC10583621 DOI: 10.1080/15476286.2023.2270344] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/28/2023] [Indexed: 10/18/2023] Open
Abstract
Most recently developed phage engineering technologies are based on the CRISPR-Cas system. Here, we present a non-CRISPR-based method for genetically engineering the Escherichia coli phages T5, T7, P1, and λ by adapting the pORTMAGE technology, which was developed for engineering bacterial genomes. The technology comprises E. coli harbouring a plasmid encoding a potent recombinase and a gene transiently silencing a repair system. Oligonucleotides with the desired phage mutation are electroporated into E. coli followed by infection of the target bacteriophage. The high efficiency of this technology, which yields 1-14% of desired recombinants, allows low-throughput screening for the desired mutant. We have demonstrated the use of this technology for single-base substitutions, for deletions of 50-201 bases, for insertions of 20 bases, and for four different phages. The technology may also be readily modified for use across many additional bacterial and phage strains.[Figure: see text].
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Affiliation(s)
- Moran G. Goren
- Department of Clinical Microbiology and Immunology, School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Tridib Mahata
- Department of Clinical Microbiology and Immunology, School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Udi Qimron
- Department of Clinical Microbiology and Immunology, School of Medicine, Tel Aviv University, Tel Aviv, Israel
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13
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Mahler M, Costa AR, van Beljouw SPB, Fineran PC, Brouns SJJ. Approaches for bacteriophage genome engineering. Trends Biotechnol 2022; 41:669-685. [PMID: 36117025 DOI: 10.1016/j.tibtech.2022.08.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 08/08/2022] [Accepted: 08/22/2022] [Indexed: 12/26/2022]
Abstract
In recent years, bacteriophage research has been boosted by a rising interest in using phage therapy to treat antibiotic-resistant bacterial infections. In addition, there is a desire to use phages and their unique proteins for specific biocontrol applications and diagnostics. However, the ability to manipulate phage genomes to understand and control gene functions, or alter phage properties such as host range, has remained challenging due to a lack of universal selectable markers. Here, we discuss the state-of-the-art techniques to engineer and select desired phage genomes using advances in cell-free methodologies and clustered regularly interspaced short palindromic repeats-CRISPR associated protein (CRISPR-Cas) counter-selection approaches.
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Affiliation(s)
- Marina Mahler
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand; Department of Bionanoscience, Delft University of Technology, Delft, the Netherlands
| | - Ana Rita Costa
- Department of Bionanoscience, Delft University of Technology, Delft, the Netherlands; Kavli Institute of Nanoscience, Delft, the Netherlands
| | - Sam P B van Beljouw
- Department of Bionanoscience, Delft University of Technology, Delft, the Netherlands; Kavli Institute of Nanoscience, Delft, the Netherlands
| | - Peter C Fineran
- Department of Microbiology and Immunology, University of Otago, Dunedin, New Zealand; Bioprotection Aotearoa, University of Otago, Dunedin, New Zealand; Genetics Otago, University of Otago, Dunedin, New Zealand
| | - Stan J J Brouns
- Department of Bionanoscience, Delft University of Technology, Delft, the Netherlands; Kavli Institute of Nanoscience, Delft, the Netherlands.
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Expansion of the Plaquing Host Range and Improvement of the Absorption Rate of a T5-like Salmonella Phage by Altering the Long Tail Fibers. Appl Environ Microbiol 2022; 88:e0089522. [PMID: 35969059 PMCID: PMC9469705 DOI: 10.1128/aem.00895-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The high host specificity of phages is a real challenge in the therapy applications of the individual phages. This study aimed to edit the long tail fiber proteins (pb1) of a T5-like phage to obtain the engineered phages with expanded plaquing host range. Two T5-like Salmonella phages with high genome sequence homology but different plaquing host ranges, narrow-host range phage vB STyj5-1 (STyj5-1) and wide-host range phage vB BD13 (BD13), were isolated and characterized. The pb1 parts of STyj5-1 were replaced by the corresponding part of BD13 using homologous recombination method to obtain the engineered phages. The alterations of the whole pb1 part or the N-terminal amino acids 1-400 of pb1 of STyj5-1 could expand their plaquing host ranges (from 20 strains to 30 strains) and improve their absorption rates (from 0.28-28.84% to 28.10-99.49%). Besides, the one-step growth curves of these engineered phages with modified pb1 parts were more similar to that of STyj5-1. The burst sizes of phages BD13, STyj5-1 and the engineered phages were 250, 236, 166, and 223 PFU per cell, respectively. The expanded plaquing host range and improved absorption rates of these engineered phages revealed that the pb1 part might be the primary determinant of the host specificities of some T5-like phages. IMPORTANCE Genetic editing can be used to change or expand the host range of phages and have been successfully applied in T2, T4 and other phages to obtain engineered phages. However, there are hardly any similar reports on T5-like phages due to that the determinant regions related to their host ranges have not been completely clarified and the editing of T5-like phages is more difficult compared to other phages. This study attempted and successfully expanded the host range of a narrow-host range T5-like phage (STyj5-1) by exchanging its whole pb1 part or the N-terminal 1-400aa of that part by a broad-host range phage (BD13). These demonstrated the pb1 part might be the primary determinant of the host specificities for some T5-like phages and provided an effective method of extension plaquing host range of these phages.
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15
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Isaev A, Andriianov A, Znobishcheva E, Zorin E, Morozova N, Severinov K. Editing of Phage Genomes—Recombineering-assisted SpCas9 Modification of Model Coliphages T7, T5, and T3. Mol Biol 2022. [DOI: 10.1134/s0026893322060073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Abstract
Bacteriophages—viruses that infect bacterial cells—are the most abundant biological entities on Earth. The use of phages in fundamental research and industry requires tools for precise manipulation of their genomes. Yet, compared to bacterial genome engineering, modification of phage genomes is challenging because of the lack of selective markers and thus requires laborious screenings of recombinant/mutated phage variants. The development of the CRISPR-Cas technologies allowed to solve this issue by the implementation of negative selection that eliminates the parental phage genomes. In this manuscript, we summarize current methods of phage genome engineering and their coupling with CRISPR-Cas technologies. We also provide examples of our successful application of these methods for introduction of specific insertions, deletions, and point mutations in the genomes of model Escherichia coli lytic phages T7, T5, and T3.
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16
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Flagellotropic Bacteriophages: Opportunities and Challenges for Antimicrobial Applications. Int J Mol Sci 2022; 23:ijms23137084. [PMID: 35806089 PMCID: PMC9266447 DOI: 10.3390/ijms23137084] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 06/18/2022] [Accepted: 06/21/2022] [Indexed: 12/22/2022] Open
Abstract
Bacteriophages (phages) are the most abundant biological entities in the biosphere. As viruses that solely infect bacteria, phages have myriad healthcare and agricultural applications including phage therapy and antibacterial treatments in the foodservice industry. Phage therapy has been explored since the turn of the twentieth century but was no longer prioritized following the invention of antibiotics. As we approach a post-antibiotic society, phage therapy research has experienced a significant resurgence for the use of phages against antibiotic-resistant bacteria, a growing concern in modern medicine. Phages are extraordinarily diverse, as are their host receptor targets. Flagellotropic (flagellum-dependent) phages begin their infection cycle by attaching to the flagellum of their motile host, although the later stages of the infection process of most of these phages remain elusive. Flagella are helical appendages required for swimming and swarming motility and are also of great importance for virulence in many pathogenic bacteria of clinical relevance. Not only is bacterial motility itself frequently important for virulence, as it allows pathogenic bacteria to move toward their host and find nutrients more effectively, but flagella can also serve additional functions including mediating bacterial adhesion to surfaces. Flagella are also a potent antigen recognized by the human immune system. Phages utilizing the flagellum for infections are of particular interest due to the unique evolutionary tradeoff they force upon their hosts: by downregulating or abolishing motility to escape infection by a flagellotropic phage, a pathogenic bacterium would also likely attenuate its virulence. This factor may lead to flagellotropic phages becoming especially potent antibacterial agents. This review outlines past, present, and future research of flagellotropic phages, including their molecular mechanisms of infection and potential future applications.
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Lee C, Kim H, Ryu S. Bacteriophage and endolysin engineering for biocontrol of food pathogens/pathogens in the food: recent advances and future trends. Crit Rev Food Sci Nutr 2022; 63:8919-8938. [PMID: 35400249 DOI: 10.1080/10408398.2022.2059442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Despite advances in modern technologies, various foodborne outbreaks have continuously threatened the food safety. The overuse of and abuse/misuse of antibiotics have escalated this threat due to the prevalence of multidrug-resistant (MDR) pathogens. Therefore, the development of new methodologies for controlling microbial contamination is extremely important to ensure the food safety. As an alternative to antibiotics, bacteriophages(phages) and derived endolysins have been proposed as novel, effective, and safe antimicrobial agents and applied for the prevention and/or eradication of bacterial contaminants even in foods and food processing facilities. In this review, we describe recent genetic and protein engineering tools for phages and endolysins. The major aim of engineering is to overcome limitations such as a narrow host range, low antimicrobial activity, and low stability of phages and endolysins. Phage engineering also aims to deter the emergence of phage resistance. In the case of endolysin engineering, enhanced antibacterial ability against Gram-negative and Gram-positive bacteria is another important goal. Here, we summarize the successful studies of phages and endolysins treatment in different types of food. Moreover, this review highlights the recent advances in engineering techniques for phages and endolysins, discusses existing challenges, and suggests technical opportunities for further development, especially in terms of antimicrobial agents in the food industry.
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Affiliation(s)
- Chanyoung Lee
- Department of Food and Animal Biotechnology, College of Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea
- Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea
- Center for Food and Bioconvergence, Seoul National University, Seoul, Republic of Korea
| | - Hyeongsoon Kim
- Department of Food and Animal Biotechnology, College of Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea
- Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea
| | - Sangryeol Ryu
- Department of Food and Animal Biotechnology, College of Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea
- Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea
- Research Institute of Agriculture and Life Sciences, College of Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea
- Center for Food and Bioconvergence, Seoul National University, Seoul, Republic of Korea
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18
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Liu S, Lu H, Zhang S, Shi Y, Chen Q. Phages against Pathogenic Bacterial Biofilms and Biofilm-Based Infections: A Review. Pharmaceutics 2022; 14:pharmaceutics14020427. [PMID: 35214158 PMCID: PMC8875263 DOI: 10.3390/pharmaceutics14020427] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 02/07/2022] [Accepted: 02/08/2022] [Indexed: 02/01/2023] Open
Abstract
Bacterial biofilms formed by pathogens are known to be hundreds of times more resistant to antimicrobial agents than planktonic cells, making it extremely difficult to cure biofilm-based infections despite the use of antibiotics, which poses a serious threat to human health. Therefore, there is an urgent need to develop promising alternative antimicrobial therapies to reduce the burden of drug-resistant bacterial infections caused by biofilms. As natural enemies of bacteria, bacteriophages (phages) have the advantages of high specificity, safety and non-toxicity, and possess great potential in the defense and removal of pathogenic bacterial biofilms, which are considered to be alternatives to treat bacterial diseases. This work mainly reviews the composition, structure and formation process of bacterial biofilms, briefly discusses the interaction between phages and biofilms, and summarizes several strategies based on phages and their derivatives against biofilms and drug-resistant bacterial infections caused by biofilms, serving the purpose of developing novel, safe and effective treatment methods against biofilm-based infections and promoting the application of phages in maintaining human health.
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Affiliation(s)
| | | | | | - Ying Shi
- Correspondence: (Y.S.); (Q.C.); Tel.: +86-139-6717-1522 (Y.S.)
| | - Qihe Chen
- Correspondence: (Y.S.); (Q.C.); Tel.: +86-139-6717-1522 (Y.S.)
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19
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Adler BA, Hessler T, Cress BF, Lahiri A, Mutalik VK, Barrangou R, Banfield J, Doudna JA. Broad-spectrum CRISPR-Cas13a enables efficient phage genome editing. Nat Microbiol 2022; 7:1967-1979. [PMID: 36316451 PMCID: PMC9712115 DOI: 10.1038/s41564-022-01258-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 09/23/2022] [Indexed: 11/05/2022]
Abstract
CRISPR-Cas13 proteins are RNA-guided RNA nucleases that defend against incoming RNA and DNA phages by binding to complementary target phage transcripts followed by general, non-specific RNA degradation. Here we analysed the defensive capabilities of LbuCas13a from Leptotrichia buccalis and found it to have robust antiviral activity unaffected by target phage gene essentiality, gene expression timing or target sequence location. Furthermore, we find LbuCas13a antiviral activity to be broadly effective against a wide range of phages by challenging LbuCas13a against nine E. coli phages from diverse phylogenetic groups. Leveraging the versatility and potency enabled by LbuCas13a targeting, we applied LbuCas13a towards broad-spectrum phage editing. Using a two-step phage-editing and enrichment method, we achieved seven markerless genome edits in three diverse phages with 100% efficiency, including edits as large as multi-gene deletions and as small as replacing a single codon. Cas13a can be applied as a generalizable tool for editing the most abundant and diverse biological entities on Earth.
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Affiliation(s)
- Benjamin A. Adler
- grid.47840.3f0000 0001 2181 7878California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA USA ,grid.47840.3f0000 0001 2181 7878Innovative Genomics Institute, University of California, Berkeley, CA USA
| | - Tomas Hessler
- grid.47840.3f0000 0001 2181 7878Innovative Genomics Institute, University of California, Berkeley, CA USA ,grid.47840.3f0000 0001 2181 7878Department of Earth and Planetary Science, University of California, Berkeley, CA USA ,grid.184769.50000 0001 2231 4551Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA USA
| | - Brady F. Cress
- grid.47840.3f0000 0001 2181 7878California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA USA ,grid.47840.3f0000 0001 2181 7878Innovative Genomics Institute, University of California, Berkeley, CA USA
| | - Arushi Lahiri
- grid.47840.3f0000 0001 2181 7878Department of Molecular and Cell Biology, University of California, Berkeley, CA USA
| | - Vivek K. Mutalik
- grid.47840.3f0000 0001 2181 7878Innovative Genomics Institute, University of California, Berkeley, CA USA ,grid.184769.50000 0001 2231 4551Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA USA
| | - Rodolphe Barrangou
- grid.47840.3f0000 0001 2181 7878Innovative Genomics Institute, University of California, Berkeley, CA USA ,grid.40803.3f0000 0001 2173 6074Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, Raleigh, NC USA
| | - Jillian Banfield
- grid.47840.3f0000 0001 2181 7878Innovative Genomics Institute, University of California, Berkeley, CA USA ,grid.47840.3f0000 0001 2181 7878Department of Earth and Planetary Science, University of California, Berkeley, CA USA ,grid.184769.50000 0001 2231 4551Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA USA ,grid.47840.3f0000 0001 2181 7878Environmental Science, Policy and Management, University of California, Berkeley, CA USA ,grid.1008.90000 0001 2179 088XUniversity of Melbourne, Melbourne, Australia
| | - Jennifer A. Doudna
- grid.47840.3f0000 0001 2181 7878California Institute for Quantitative Biosciences (QB3), University of California, Berkeley, CA USA ,grid.47840.3f0000 0001 2181 7878Innovative Genomics Institute, University of California, Berkeley, CA USA ,grid.184769.50000 0001 2231 4551Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA USA ,grid.47840.3f0000 0001 2181 7878Howard Hughes Medical Institute, University of California, Berkeley, CA USA ,grid.47840.3f0000 0001 2181 7878Department of Chemistry, University of California, Berkeley, CA USA ,grid.184769.50000 0001 2231 4551MBIB Division, Lawrence Berkeley National Laboratory, Berkeley, CA USA
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20
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Forsberg KJ, Schmidtke DT, Werther R, Uribe RV, Hausman D, Sommer MOA, Stoddard BL, Kaiser BK, Malik HS. The novel anti-CRISPR AcrIIA22 relieves DNA torsion in target plasmids and impairs SpyCas9 activity. PLoS Biol 2021; 19:e3001428. [PMID: 34644300 PMCID: PMC8545432 DOI: 10.1371/journal.pbio.3001428] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 10/25/2021] [Accepted: 09/28/2021] [Indexed: 11/18/2022] Open
Abstract
To overcome CRISPR-Cas defense systems, many phages and mobile genetic elements (MGEs) encode CRISPR-Cas inhibitors called anti-CRISPRs (Acrs). Nearly all characterized Acrs directly bind Cas proteins to inactivate CRISPR immunity. Here, using functional metagenomic selection, we describe AcrIIA22, an unconventional Acr found in hypervariable genomic regions of clostridial bacteria and their prophages from human gut microbiomes. AcrIIA22 does not bind strongly to SpyCas9 but nonetheless potently inhibits its activity against plasmids. To gain insight into its mechanism, we obtained an X-ray crystal structure of AcrIIA22, which revealed homology to PC4-like nucleic acid-binding proteins. Based on mutational analyses and functional assays, we deduced that acrIIA22 encodes a DNA nickase that relieves torsional stress in supercoiled plasmids. This may render them less susceptible to SpyCas9, which uses free energy from negative supercoils to form stable R-loops. Modifying DNA topology may provide an additional route to CRISPR-Cas resistance in phages and MGEs.
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Affiliation(s)
- Kevin J. Forsberg
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- * E-mail:
| | - Danica T. Schmidtke
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Rachel Werther
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Ruben V. Uribe
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Deanna Hausman
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Morten O. A. Sommer
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Lyngby, Denmark
| | - Barry L. Stoddard
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Brett K. Kaiser
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Department of Biology, Seattle University, Seattle, Washington, United States of America
| | - Harmit S. Malik
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
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