1
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Yang Y, Zhou P, Tian D, Wang W, Zhou Y, Jiang X. CRISPR-Cas3 and type I restriction-modification team up against bla KPC-IncF plasmid transfer in Klebsiella pneumoniae. BMC Microbiol 2024; 24:240. [PMID: 38961341 PMCID: PMC11223367 DOI: 10.1186/s12866-024-03381-7] [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: 12/04/2023] [Accepted: 06/18/2024] [Indexed: 07/05/2024] Open
Abstract
OBJECTIVE We explored whether the Clustered regularly interspaced short palindromic repeat (CRISPR)-Cas and restriction-modification (R-M) systems are compatible and act together to resist plasmid attacks. METHODS 932 global whole-genome sequences from GenBank, and 459 K. pneumoniae isolates from six provinces of China, were collected to investigate the co-distribution of CRISPR-Cas, R-M systems, and blaKPC plasmid. Conjugation and transformation assays were applied to explore the anti-plasmid function of CRISPR and R-M systems. RESULTS We found a significant inverse correlation between the presence of CRISPR and R-M systems and blaKPC plasmids in K. pneumoniae, especially when both systems cohabited in one host. The multiple matched recognition sequences of both systems in blaKPC-IncF plasmids (97%) revealed that they were good targets for both systems. Furthermore, the results of conjugation assay demonstrated that CRISPR-Cas and R-M systems in K. pneumoniae could effectively hinder blaKPC plasmid invasion. Notably, CRISPR-Cas and R-M worked together to confer a 4-log reduction in the acquisition of blaKPC plasmid in conjugative events, exhibiting robust synergistic anti-plasmid immunity. CONCLUSIONS Our results indicate the synergistic role of CRISPR and R-M in regulating horizontal gene transfer in K. pneumoniae and rationalize the development of antimicrobial strategies that capitalize on the immunocompromised status of KPC-KP.
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Affiliation(s)
- Yang Yang
- Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China
- Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, China
| | - Peiyao Zhou
- Department of Laboratory Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Dongxing Tian
- Department of Laboratory Medicine, Shanghai Medical College, Huashan Hospital, Fudan University, Shanghai, China
| | - Weiwen Wang
- Department of Laboratory Medicine, Shanghai Medical College, Huashan Hospital, Fudan University, Shanghai, China
| | - Ying Zhou
- Department of Clinical Laboratory Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, People's Republic of China.
| | - Xiaofei Jiang
- Department of Laboratory Medicine, Shanghai Medical College, Huashan Hospital, Fudan University, Shanghai, China.
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2
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Pradeu T, Thomma BPHJ, Girardin SE, Lemaitre B. The conceptual foundations of innate immunity: Taking stock 30 years later. Immunity 2024; 57:613-631. [PMID: 38599162 DOI: 10.1016/j.immuni.2024.03.007] [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: 01/14/2024] [Revised: 02/23/2024] [Accepted: 03/06/2024] [Indexed: 04/12/2024]
Abstract
While largely neglected over decades during which adaptive immunity captured most of the attention, innate immune mechanisms have now become central to our understanding of immunology. Innate immunity provides the first barrier to infection in vertebrates, and it is the sole mechanism of host defense in invertebrates and plants. Innate immunity also plays a critical role in maintaining homeostasis, shaping the microbiota, and in disease contexts such as cancer, neurodegeneration, metabolic syndromes, and aging. The emergence of the field of innate immunity has led to an expanded view of the immune system, which is no longer restricted to vertebrates and instead concerns all metazoans, plants, and even prokaryotes. The study of innate immunity has given rise to new concepts and language. Here, we review the history and definition of the core concepts of innate immunity, discussing their value and fruitfulness in the long run.
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Affiliation(s)
- Thomas Pradeu
- CNRS UMR 5164 ImmunoConcept, University of Bordeaux, Bordeaux, France; Department of Biological and Medical Sciences, University of Bordeaux, Bordeaux, France; Presidential Fellow, Chapman University, Orange, CA, USA.
| | - Bart P H J Thomma
- Institute for Plant Sciences, University of Cologne, Cologne, Germany
| | - Stephen E Girardin
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Bruno Lemaitre
- Global Health Institute, School of Life Science, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
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3
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Dai P, Hu D. The making of hypervirulent Klebsiella pneumoniae. J Clin Lab Anal 2022; 36:e24743. [PMID: 36347819 PMCID: PMC9757020 DOI: 10.1002/jcla.24743] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 10/01/2022] [Accepted: 10/09/2022] [Indexed: 10/08/2023] Open
Abstract
Klebsiella pneumoniae is a notorious bacterium in clinical practice. Virulence, carbapenem-resistance and their convergence among K. pneumoniae are extensively discussed in this article. Hypervirulent K. pneumoniae (HvKP) has spread from the Asian Pacific Rim to the world, inducing various invasive infections, such as pyogenic liver abscess, endophthalmitis, and meningitis. Furthermore, HvKP has acquired more and more drug resistance. Among multidrug-resistant HvKP, hypervirulent carbapenem-resistant K. pneumoniae (Hv-CRKP), and carbapenem-resistant hypervirulent K. pneumoniae (CR-HvKP) are both devastating for their extreme drug resistance and virulence. The hypervirulence of HvKP is primarily attributed to hypercapsule, macromolecular exopolysaccharides, or excessive siderophores, although it has many other factors, for example, lipopolysaccharides, fimbriae, and porins. In contrast with classical determination of HvKP, that is, animal lethality test, molecular determination could be an optional and practical method after improvement. HvKP, including Hv-CRKP and CR-HvKP, has been progressing. R-M and CRISPR-Cas systems may play pivotal roles in such evolutions. Hv-CRKP and CR-HvKP, in particular the former, should be of severe concern due to their being more and more prevalent.
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Affiliation(s)
- Piaopiao Dai
- Department of Laboratory MedicineTaizhou Municipal HospitalTaizhouChina
| | - Dakang Hu
- Department of Laboratory MedicineTaizhou Municipal HospitalTaizhouChina
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4
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Vialetto E, Yu Y, Collins SP, Wandera KG, Barquist L, Beisel CL. A target expression threshold dictates invader defense and prevents autoimmunity by CRISPR-Cas13. Cell Host Microbe 2022; 30:1151-1162.e6. [PMID: 35690065 PMCID: PMC9590104 DOI: 10.1016/j.chom.2022.05.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 03/30/2022] [Accepted: 05/17/2022] [Indexed: 11/20/2022]
Abstract
CRISPR-Cas systems must enact robust immunity against foreign genetic material without inducing cytotoxic autoimmunity. For type VI systems that use Cas13 nucleases and recognize RNA targets, immune activation requires extensive CRISPR RNA (crRNA) guide-target complementarity and a target-flanking motif. Here, we report a third requirement shaping the immune response: the expression of the target transcript exceeding a threshold. We found that endogenous non-essential transcripts targeted by crRNAs rarely elicited autoimmunity. Instead, autoimmune induction required over-expressing the targeted transcripts above a threshold. A genome-wide screen confirmed target expression levels as a global determinant of cytotoxic autoimmunity and revealed that this threshold shifts with each guide-target pair. This threshold further ensured defense against a lytic bacteriophage yet allowed the tolerance of a targeted beneficial gene expressed from an invading plasmid. These findings establish target expression levels as an additional criterion for immune defense by RNA-targeting CRISPR-Cas systems, preventing autoimmunity and distinguishing pathogenic and benign invaders.
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Affiliation(s)
- Elena Vialetto
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), 97080 Würzburg, Germany
| | - Yanying Yu
- 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
| | - Katharina G Wandera
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), 97080 Würzburg, Germany
| | - Lars Barquist
- 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
| | - Chase L Beisel
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz Centre for Infection Research (HZI), 97080 Würzburg, Germany; Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, USA; Medical Faculty, University of Würzburg, 97080 Würzburg, Germany.
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5
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The RD2 Pathogenicity Island Modifies the Disease Potential of the Group A Streptococcus. Infect Immun 2021; 89:e0072220. [PMID: 33820819 DOI: 10.1128/iai.00722-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Serotype M28 isolates of the group A Streptococcus (GAS; Streptococcus pyogenes) are nonrandomly associated with cases of puerperal sepsis, a potentially life-threatening infection that can occur in women following childbirth. Previously, we discovered that the 36.3-kb RD2 pathogenicity island, which is present in serotype M28 isolates but lacking from most other isolates, promotes the ability of M28 GAS to colonize the female reproductive tract. Here, we performed a gain-of-function study in which we introduced RD2 into representative serotype M1, M49, and M59 isolates and assessed the phenotypic consequences of RD2 acquisition. All RD2-containing derivatives colonized a higher percentage of mice, and at higher CFU levels, than did the parental isolates in a mouse vaginal colonization model. However, for two additional phenotypes, survival in heparinized whole human blood and adherence to two human vaginal epithelial cell lines, there were serotype-specific differences from RD2 acquisition. Using transcriptomic comparisons, we identified that such differences may be a consequence of RD2 altering the abundance of transcripts from select core genome genes along serotype-specific lines. Our study is the first that interrogates RD2 function in GAS serotypes other than M28 isolates, shedding light on variability in the phenotypic consequences of RD2 acquisition and informing on why this mobile genetic element is not ubiquitous in the GAS population.
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6
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Zhang WJ, Zhang C, Zhou S, Li XG, Mangenot S, Fouteau S, Guerin T, Qi XQ, Yang J, Bartlett DH, Wu LF. Comparative genomic analysis of obligately piezophilic Moritella yayanosii DB21MT-5 reveals bacterial adaptation to the Challenger Deep, Mariana Trench. Microb Genom 2021; 7:000591. [PMID: 34319226 PMCID: PMC8477399 DOI: 10.1099/mgen.0.000591] [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: 10/23/2020] [Accepted: 04/20/2021] [Indexed: 01/19/2023] Open
Abstract
Hadal trenches are the deepest but underexplored ecosystems on the Earth. Inhabiting the trench bottom is a group of micro-organisms termed obligate piezophiles that grow exclusively under high hydrostatic pressures (HHP). To reveal the genetic and physiological characteristics of their peculiar lifestyles and microbial adaptation to extreme high pressures, we sequenced the complete genome of the obligately piezophilic bacterium Moritella yayanosii DB21MT-5 isolated from the deepest oceanic sediment at the Challenger Deep, Mariana Trench. Through comparative analysis against pressure sensitive and deep-sea piezophilic Moritella strains, we identified over a hundred genes that present exclusively in hadal strain DB21MT-5. The hadal strain encodes fewer signal transduction proteins and secreted polysaccharases, but has more abundant metal ion transporters and the potential to utilize plant-derived saccharides. Instead of producing osmolyte betaine from choline as other Moritella strains, strain DB21MT-5 ferments on choline within a dedicated bacterial microcompartment organelle. Furthermore, the defence systems possessed by DB21MT-5 are distinct from other Moritella strains but resemble those in obligate piezophiles obtained from the same geographical setting. Collectively, the intensive comparative genomic analysis of an obligately piezophilic strain Moritella yayanosii DB21MT-5 demonstrates a depth-dependent distribution of energy metabolic pathways, compartmentalization of important metabolism and use of distinct defence systems, which likely contribute to microbial adaptation to the bottom of hadal trench.
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Affiliation(s)
- Wei-Jia Zhang
- Laboratory of Deep-Sea Microbial Cell Biology, Institute of Deep-Sea Science and Engineering, Chinese Academy of Sciences, PR China
- France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), Marseille, France / IDSSE-CAS, Sanya, PR China
- Institution of Deep-Sea Life Sciences, Hainan Deep-Sea Technology Laboratory, Sanya, PR China
| | - Chan Zhang
- Laboratory of Deep-Sea Microbial Cell Biology, Institute of Deep-Sea Science and Engineering, Chinese Academy of Sciences, PR China
- Present address: College of Horticulture, Hainan University, No. 58, Renmin Avenue, Haikou, PR China
| | - Siyu Zhou
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
| | - Xue-Gong Li
- Laboratory of Deep-Sea Microbial Cell Biology, Institute of Deep-Sea Science and Engineering, Chinese Academy of Sciences, PR China
- France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), Marseille, France / IDSSE-CAS, Sanya, PR China
- Institution of Deep-Sea Life Sciences, Hainan Deep-Sea Technology Laboratory, Sanya, PR China
| | - Sophie Mangenot
- Génomique Métabolique, CEA, Genoscope, Institut François Jacob, Université d’Évry, Université Paris-Saclay, CNRS, Evry, France
| | - Stéphanie Fouteau
- Génomique Métabolique, CEA, Genoscope, Institut François Jacob, Université d’Évry, Université Paris-Saclay, CNRS, Evry, France
| | - Thomas Guerin
- Génomique Métabolique, CEA, Genoscope, Institut François Jacob, Université d’Évry, Université Paris-Saclay, CNRS, Evry, France
| | - Xiao-Qing Qi
- Laboratory of Deep-Sea Microbial Cell Biology, Institute of Deep-Sea Science and Engineering, Chinese Academy of Sciences, PR China
- France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), Marseille, France / IDSSE-CAS, Sanya, PR China
- Institution of Deep-Sea Life Sciences, Hainan Deep-Sea Technology Laboratory, Sanya, PR China
| | - Jian Yang
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, PR China
| | - Douglas H. Bartlett
- Marine Biology Research Division, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093-0202, USA
| | - Long-Fei Wu
- France-China Joint Laboratory for Evolution and Development of Magnetotactic Multicellular Organisms (LIA-MagMC), Marseille, France / IDSSE-CAS, Sanya, PR China
- Aix-Marseille Université, CNRS, LCB UMR 7257, IMM, IM2B, Marseille, France
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7
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Slaymaker IM, Gaudelli NM. Engineering Cas9 for human genome editing. Curr Opin Struct Biol 2021; 69:86-98. [PMID: 33964614 DOI: 10.1016/j.sbi.2021.03.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 03/07/2021] [Accepted: 03/12/2021] [Indexed: 12/26/2022]
Abstract
Since the initial reports describing CRISPR-Cas9, labs across the globe have leveraged this valuable gene editing tool to alter the genomes of living cells. With the goal of generating more precise and efficient genome changes, scientists and engineers have mutated, evolved, and covalently altered Cas9 in order to predictably edit the genetic code. Here, we highlight recent advancements and contributions to the growing field of Cas9 engineering. We present key aspects of Cas9 engineering efforts focused on sgRNA manipulation, PAM-recognition, specificity, deaminase fusions, reverse-transcriptase fusions, and structural rearrangements of this important gene-modifying tool.
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Affiliation(s)
- Ian M Slaymaker
- Beam Therapeutics, 26 Landsdowne St., Cambridge, MA 02139, USA.
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8
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de Almeida NAA, Ribeiro CRDA, Raposo JV, de Paula VS. Immunotherapy and Gene Therapy for Oncoviruses Infections: A Review. Viruses 2021; 13:822. [PMID: 34063186 PMCID: PMC8147456 DOI: 10.3390/v13050822] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 02/19/2021] [Accepted: 02/24/2021] [Indexed: 12/24/2022] Open
Abstract
Immunotherapy has been shown to be highly effective in some types of cancer caused by viruses. Gene therapy involves insertion or modification of a therapeutic gene, to correct for inappropriate gene products that cause/may cause diseases. Both these types of therapy have been used as alternative ways to avoid cancers caused by oncoviruses. In this review, we summarize recent studies on immunotherapy and gene therapy including the topics of oncolytic immunotherapy, immune checkpoint inhibitors, gene replacement, antisense oligonucleotides, RNA interference, clustered regularly interspaced short palindromic repeats Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-based gene editing, transcription activator-like effector nucleases (TALENs) and custom treatment for Epstein-Barr virus, human T-lymphotropic virus 1, hepatitis B virus, human papillomavirus, hepatitis C virus, herpesvirus associated with Kaposi's sarcoma, Merkel cell polyomavirus, and cytomegalovirus.
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Affiliation(s)
| | | | | | - Vanessa Salete de Paula
- Laboratory of Molecular Virology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, 21040-360 Rio de Janeiro, Brazil; (N.A.A.d.A.); (C.R.d.A.R.); (J.V.R.)
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9
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Zhou Y, Tian D, Tang Y, Yu L, Huang Y, Li G, Li M, Wang Y, Yang Z, Poirel L, Jiang X. High-risk KPC-producing Klebsiella pneumoniae lack type I R-M systems. Int J Antimicrob Agents 2020; 56:106050. [DOI: 10.1016/j.ijantimicag.2020.106050] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 06/03/2020] [Accepted: 06/06/2020] [Indexed: 12/16/2022]
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10
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A phylogenetic test of the role of CRISPR-Cas in limiting plasmid acquisition and prophage integration in bacteria. Plasmid 2019; 104:102418. [PMID: 31195029 DOI: 10.1016/j.plasmid.2019.102418] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 06/01/2019] [Accepted: 06/05/2019] [Indexed: 12/17/2022]
Abstract
CRISPR-Cas is a prokaryotic defense system capable of protecting the cell from damaging foreign genetic elements. However, some genetic elements can be beneficial, which suggests the hypothesis that bacteria with CRISPR-Cas incur a cost of reduced intake of mutualistic plasmids and prophage. Here we present the first robust test of this hypothesis that controls for phylogenic and ecological biases in the distribution of CRISPR-Cas. We filtered the available genomic data (~7000 strains from ~2100 species) by first selecting all pairs of conspecific strains, one with and one without CRISPR-Cas (controlling ecological bias), and second by retaining only one such pair per bacterial family (controlling phylogenetic bias), resulting in pairs representing 38 bacterial families. Analysis of these pairs of bacterial strains showed that on average the CRISPR-Cas strain of each pair contained significantly fewer plasmids than its CRISPR-Cas negative partner (0.86 vs. 1.86). It also showed that the CRISPR-Cas positive strains had 31% fewer intact prophage (1.17 vs. 1.75), but the effect was highly variable and not significant. These results support the hypothesis that CRISPR-Cas reduces the rate of plasmid-mediated HGT and, given the abundant evidence of beneficial genes carried by plasmids, provide a clear example of a cost associated with the CRISPR-Cas system.
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11
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Natural tuning of restriction endonuclease synthesis by cluster of rare arginine codons. Sci Rep 2019; 9:5808. [PMID: 30967604 PMCID: PMC6456624 DOI: 10.1038/s41598-019-42311-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 03/28/2019] [Indexed: 01/21/2023] Open
Abstract
Restriction–modification (R-M) systems are highly widespread among bacteria and archaea, and they appear to play a pivotal role in modulating horizontal gene transfer, as well as in protecting the host organism against viruses and other invasive DNA particles. Type II R-M systems specify two independent enzymes: a restriction endonuclease (REase) and protective DNA methyltransferase (MTase). If the cell is to survive, the counteracting activities as toxin and antitoxin, must be finely balanced in vivo. The molecular basis of this regulatory process remains unclear and current searches for regulatory elements in R-M modules are focused mainly at the transcription step. In this report, we show new aspects of REase control that are linked to translation. We used the EcoVIII R-M system as a model. Both, the REase and MTase genes for this R-M system contain an unusually high number of rare arginine codons (AGA and AGG) when compared to the rest of the E. coli K-12 genome. Clusters of these codons near the N-terminus of the REase greatly affect the translational efficiency. Changing these to higher frequency codons for E. coli (CGC) improves the REase synthesis, making the R-M system more potent to defend its host against bacteriophages. However, this improved efficiency in synthesis reduces host fitness due to increased autorestriction. We hypothesize that expression of the endonuclease gene can be modulated depending on the host genetic context and we propose a novel post-transcriptional mode of R–M system regulation that alleviates the potential lethal action of the restriction enzyme.
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12
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Djordjevic M, Rodic A, Graovac S. From biophysics to 'omics and systems biology. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2019; 48:413-424. [PMID: 30972433 DOI: 10.1007/s00249-019-01366-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 02/12/2019] [Accepted: 04/03/2019] [Indexed: 01/03/2023]
Abstract
Recent decades brought a revolution to biology, driven mainly by exponentially increasing amounts of data coming from "'omics" sciences. To handle these data, bioinformatics often has to combine biologically heterogeneous signals, for which methods from statistics and engineering (e.g. machine learning) are often used. While such an approach is sometimes necessary, it effectively treats the underlying biological processes as a black box. Similarly, systems biology deals with inherently complex systems, characterized by a large number of degrees of freedom, and interactions that are highly non-linear. To deal with this complexity, the underlying physical interactions are often (over)simplified, such as in Boolean modelling of network dynamics. In this review, we argue for the utility of applying a biophysical approach in bioinformatics and systems biology, including discussion of two examples from our research which address sequence analysis and understanding intracellular gene expression dynamics.
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Affiliation(s)
- Marko Djordjevic
- Faculty of Biology, Institute of Physiology and Biochemistry, University of Belgrade, Belgrade, Serbia.
| | - Andjela Rodic
- Faculty of Biology, Institute of Physiology and Biochemistry, University of Belgrade, Belgrade, Serbia.,Interdisciplinary PhD Program in Biophysics, University of Belgrade, Belgrade, Serbia
| | - Stefan Graovac
- Faculty of Biology, Institute of Physiology and Biochemistry, University of Belgrade, Belgrade, Serbia.,Interdisciplinary PhD Program in Biophysics, University of Belgrade, Belgrade, Serbia
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13
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Faure G, Makarova KS, Koonin EV. CRISPR-Cas: Complex Functional Networks and Multiple Roles beyond Adaptive Immunity. J Mol Biol 2018; 431:3-20. [PMID: 30193985 DOI: 10.1016/j.jmb.2018.08.030] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 08/28/2018] [Accepted: 08/29/2018] [Indexed: 01/26/2023]
Abstract
CRISPR-Cas is a prokaryotic adaptive immune system that functions by incorporating fragments of foreign DNA into CRISPR arrays. The arrays containing spacers derived from foreign DNA are transcribed, and the transcripts are processed to generate spacer-containing mature CRISPR-RNAs that are employed as guides to specifically recognize and cleave the DNA or RNA of the cognate parasitic genetic elements. The CRISPR-Cas systems show remarkable complexity and diversity of molecular organization and appear to be involved in various cellular functions that are distinct from, even if connected to, adaptive immunity. In this review, we discuss some of such functional links of CRISPR-Cas systems including their effect on horizontal gene transfer that can be either inhibitory or stimulatory, connections between CRISPR-Cas and DNA repair systems as well as programmed cell death and signal transduction mechanisms, and potential role of CRISPR-Cas in transposon integration and plasmid maintenance. The interplay between the primary function of CRISPR-Cas as an adaptive immunity mechanism and these other roles defines the richness of the biological effects of these systems and affects their spread among bacteria and archaea.
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Affiliation(s)
- Guilhem Faure
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - Kira S Makarova
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA.
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Food Spoilage-Associated Leuconostoc, Lactococcus, and Lactobacillus Species Display Different Survival Strategies in Response to Competition. Appl Environ Microbiol 2018; 84:AEM.00554-18. [PMID: 29678911 DOI: 10.1128/aem.00554-18] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 04/12/2018] [Indexed: 12/27/2022] Open
Abstract
Psychrotrophic lactic acid bacteria (LAB) are the prevailing spoilage organisms in packaged cold-stored meat products. Species composition and metabolic activities of such LAB spoilage communities are determined by the nature of the meat product, storage conditions, and interspecies interactions. Our knowledge of system level responses of LAB during such interactions is very limited. To expand it, we studied interactions between three common psychrotrophic spoilage LAB (Leuconostoc gelidum, Lactococcus piscium, and Lactobacillus oligofermentans) by comparing their time course transcriptome profiles obtained during their growth in individual, pairwise, and triple cultures. The study revealed how these LAB employed different strategies to cope with the consequences of interspecies competition. The fastest-growing bacterium, Le. gelidum, attempted to enhance its nutrient-scavenging and growth capabilities in the presence of other LAB through upregulation of carbohydrate catabolic pathways, pyruvate fermentation enzymes, and ribosomal proteins, whereas the slower-growing Lc. piscium and Lb. oligofermentans downregulated these functions. These findings may explain the competitive success and predominance of Le. gelidum in a variety of spoiled foods. Peculiarly, interspecies interactions induced overexpression of prophage genes and restriction modification systems (mechanisms of DNA exchange and protection against it) in Lc. piscium and Lb. oligofermentans but not in Le. gelidum Cocultivation induced also overexpression of the numerous putative adhesins in Lb. oligofermentans These adhesins might contribute to the survival of this slowly growing bacterium in actively growing meat spoilage communities.IMPORTANCE Despite the apparent relevance of LAB for biotechnology and human health, interactions between members of LAB communities are not well known. Knowledge of such interactions is crucial for understanding how these communities function and, consequently, whether there is any possibility to develop new strategies to interfere with their growth and to postpone spoilage of packaged and refrigerated foods. With the help of controlled experiments, detailed regulation events can be observed. This study gives an insight into the system level interactions and the different competition-induced survival strategies related to enhanced uptake and catabolism of carbon sources, overexpression of adhesins and putative bacteriocins, and the induction of exchange of genetic material. Even though this experiment dealt with only three LAB strains in vitro, these findings agreed well with the relative abundance patterns typically reported for these species in natural food microbial communities.
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Grzybek M, Golonko A, Górska A, Szczepaniak K, Strachecka A, Lass A, Lisowski P. The CRISPR/Cas9 system sheds new lights on the biology of protozoan parasites. Appl Microbiol Biotechnol 2018; 102:4629-4640. [PMID: 29626235 PMCID: PMC5954013 DOI: 10.1007/s00253-018-8927-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 03/06/2018] [Indexed: 01/04/2023]
Abstract
The CRISPR/Cas9 system, a natural defence system of bacterial organisms, has recently been used to modify genomes of the most important protozoa parasites. Successful genome manipulations with the CRISPR/Cas9 system are changing the present view of genetics in parasitology. The application of this system offers a major chance to overcome the current restriction in culturing, maintaining and analysing protozoan parasites, and allows dynamic analysis of parasite genes functions, leading to a better understanding of pathogenesis. CRISPR/Cas9 system will have a significant influence on the process of developing novel drugs and treatment strategies against protozoa parasites.
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Affiliation(s)
- Maciej Grzybek
- Department of Tropical Parasitology, Medical University of Gdansk, Powstania Styczniowego 9b, 81-519 Gdynia, Poland
| | - Aleksandra Golonko
- Department of Biotechnology, Bialystok University of Technology, Wiejska 45E, 15-351, Bialystok, Poland
| | - Aleksandra Górska
- Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Akademicka 13, 20-950 Lublin, Poland
| | - Klaudiusz Szczepaniak
- Faculty of Veterinary Medicine, University of Life Sciences in Lublin, Akademicka 13, 20-950 Lublin, Poland
| | - Aneta Strachecka
- Faculty of Biology, Animal Sciences and Bioeconomy, University of Life Sciences in Lublin, Akademicka 13, 20-950 Lublin, Poland
| | - Anna Lass
- Department of Tropical Parasitology, Medical University of Gdansk, Powstania Styczniowego 9b, 81-519 Gdynia, Poland
| | - Paweł Lisowski
- Department of Molecular Biology, Institute of Genetics and Animal Breeding PAS, Postepu 36A, 05-552 Jastrzebiec, Poland
- iPS Cell-Based Disease Modeling Group, Max-Delbrück-Center for Molecular Medicine (MDC) in the Helmholtz Association, Robert-Rössle-Str. 10, 13092 Berlin, Germany
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16
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Incomplete prophage tolerance by type III-A CRISPR-Cas systems reduces the fitness of lysogenic hosts. Nat Commun 2018; 9:61. [PMID: 29302058 PMCID: PMC5754349 DOI: 10.1038/s41467-017-02557-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 12/11/2017] [Indexed: 12/26/2022] Open
Abstract
CRISPR–Cas systems offer an immune mechanism through which prokaryotic hosts can acquire heritable resistance to genetic parasites, including temperate phages. Co-transcriptional DNA and RNA targeting by type III-A CRISPR–Cas systems restricts temperate phage lytic infections while allowing lysogenic infections to be tolerated under conditions where the prophage targets are transcriptionally repressed. However, long-term consequences of this phenomenon have not been explored. Here we show that maintenance of conditionally tolerant type III-A systems can produce fitness costs within populations of Staphylococcus aureus lysogens. The fitness costs depend on the activity of prophage-internal promoters and type III-A Cas nucleases implicated in targeting, can be more severe in double lysogens, and are alleviated by spacer-target mismatches which do not abrogate immunity during the lytic cycle. These findings suggest that persistence of type III-A systems that target endogenous prophages could be enhanced by spacer-target mismatches, particularly among populations that are prone to polylysogenization. CRISPR-Cas systems, such as type III-A CRISPR-Cas, provide an immune mechanism for prokaryotic hosts to resist parasites, including phages. Here, the authors show that maintenance of conditionally tolerant type III-A systems can affect the fitness of Staphylococcus aureus lysogens.
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17
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Do fungi have an innate immune response? An NLR-based comparison to plant and animal immune systems. PLoS Pathog 2017; 13:e1006578. [PMID: 29073287 PMCID: PMC5658179 DOI: 10.1371/journal.ppat.1006578] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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18
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Soppe JA, Lebbink RJ. Antiviral Goes Viral: Harnessing CRISPR/Cas9 to Combat Viruses in Humans. Trends Microbiol 2017; 25:833-850. [PMID: 28522157 DOI: 10.1016/j.tim.2017.04.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 04/07/2017] [Accepted: 04/19/2017] [Indexed: 12/11/2022]
Abstract
The clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated (Cas) systems are RNA-guided sequence-specific prokaryotic antiviral immune systems. In prokaryotes, small RNA molecules guide Cas effector endonucleases to invading foreign genetic elements in a sequence-dependent manner, resulting in DNA cleavage by the endonuclease upon target binding. A rewired CRISPR/Cas9 system can be used for targeted and precise genome editing in eukaryotic cells. CRISPR/Cas has also been harnessed to target human pathogenic viruses as a potential new antiviral strategy. Here, we review recent CRISPR/Cas9-based approaches to combat specific human viruses in humans and discuss challenges that need to be overcome before CRISPR/Cas9 may be used in the clinic as an antiviral strategy.
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Affiliation(s)
- Jasper Adriaan Soppe
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Robert Jan Lebbink
- Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands.
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19
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Abstract
Clustered regularly interspaced short palindromic repeats and CRISPR-associated protein (CRISPR-Cas) systems store the memory of past encounters with foreign DNA in unique spacers that are inserted between direct repeats in CRISPR arrays. For only a small fraction of the spacers, homologous sequences, called protospacers, are detectable in viral, plasmid, and microbial genomes. The rest of the spacers remain the CRISPR “dark matter.” We performed a comprehensive analysis of the spacers from all CRISPR-cas loci identified in bacterial and archaeal genomes, and we found that, depending on the CRISPR-Cas subtype and the prokaryotic phylum, protospacers were detectable for 1% to about 19% of the spacers (~7% global average). Among the detected protospacers, the majority, typically 80 to 90%, originated from viral genomes, including proviruses, and among the rest, the most common source was genes that are integrated into microbial chromosomes but are involved in plasmid conjugation or replication. Thus, almost all spacers with identifiable protospacers target mobile genetic elements (MGE). The GC content, as well as dinucleotide and tetranucleotide compositions, of microbial genomes, their spacer complements, and the cognate viral genomes showed a nearly perfect correlation and were almost identical. Given the near absence of self-targeting spacers, these findings are most compatible with the possibility that the spacers, including the dark matter, are derived almost completely from the species-specific microbial mobilomes. The principal function of CRISPR-Cas systems is thought to be protection of bacteria and archaea against viruses and other parasitic genetic elements. The CRISPR defense function is mediated by sequences from parasitic elements, known as spacers, that are inserted into CRISPR arrays and then transcribed and employed as guides to identify and inactivate the cognate parasitic genomes. However, only a small fraction of the CRISPR spacers match any sequences in the current databases, and of these, only a minority correspond to known parasitic elements. We show that nearly all spacers with matches originate from viral or plasmid genomes that are either free or have been integrated into the host genome. We further demonstrate that spacers with no matches have the same properties as those of identifiable origins, strongly suggesting that all spacers originate from mobile elements.
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20
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Claverie JM, Abergel C. CRISPR-Cas-like system in giant viruses: why MIMIVIRE is not likely to be an adaptive immune system. Virol Sin 2017; 31:193-6. [PMID: 27315813 DOI: 10.1007/s12250-016-3801-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Jean-Michel Claverie
- Structural and Genomic Information Laboratory (UMR7256), CNRS Aix Marseille University, Mediterranean Institute of Microbiology (FR 3479), Marseille, France.
| | - Chantal Abergel
- Structural and Genomic Information Laboratory (UMR7256), CNRS Aix Marseille University, Mediterranean Institute of Microbiology (FR 3479), Marseille, France.
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Liu XF, Hummel M, Abecassis M. Epigenetic regulation of cellular and cytomegalovirus genes during myeloid cell development. ACTA ACUST UNITED AC 2017; 3. [PMID: 28707002 DOI: 10.18103/imr.v3i3.385] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Myeloid cells are important cell types that carry human cytomegalovirus. Latent viral DNA is present in CD34+ progenitor cells and their derived monocytes. However, differentiation of latently infected monocytes to mature macrophages or dendritic cells causes reactivation of latent viruses. During hematopoietic development, pluripotent genes are repressed, and lineage specific genes are activated in a step-wise manner. This process is governed by cell-type specific chromatin states. Enhancers in the hematopoietic system are highly dynamic and established by pioneer (first tier) transcription factors (TFs), which set the stage for second and third tier TF binding. In this review, we examine the epigenetic mechanisms that regulate myeloid cell development, cell identity, and activation with a special focus on factors that regulate viral gene expression and the status of viral infection in myeloid cells.
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Affiliation(s)
- Xue-Feng Liu
- Comprehensive Transplant Center, Division of Organ Transplantation, Department of Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611
| | - Mary Hummel
- Comprehensive Transplant Center, Division of Organ Transplantation, Department of Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611
| | - Michael Abecassis
- Comprehensive Transplant Center, Division of Organ Transplantation, Department of Surgery, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611
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Westra ER, Dowling AJ, Broniewski JM, van Houte S. Evolution and Ecology of CRISPR. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2016. [DOI: 10.1146/annurev-ecolsys-121415-032428] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Edze R. Westra
- Environment and Sustainability Institute and Centre for Ecology and Conservation, Biosciences, University of Exeter, Tremough Campus, Penryn TR10 9FE, United Kingdom;
| | - Andrea J. Dowling
- Environment and Sustainability Institute and Centre for Ecology and Conservation, Biosciences, University of Exeter, Tremough Campus, Penryn TR10 9FE, United Kingdom;
| | - Jenny M. Broniewski
- Environment and Sustainability Institute and Centre for Ecology and Conservation, Biosciences, University of Exeter, Tremough Campus, Penryn TR10 9FE, United Kingdom;
| | - Stineke van Houte
- Environment and Sustainability Institute and Centre for Ecology and Conservation, Biosciences, University of Exeter, Tremough Campus, Penryn TR10 9FE, United Kingdom;
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23
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Friendly Fire: Biological Functions and Consequences of Chromosomal Targeting by CRISPR-Cas Systems. J Bacteriol 2016; 198:1481-6. [PMID: 26929301 DOI: 10.1128/jb.00086-16] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Clustered regularly interspaced short palindromic repeat (CRISPR)-associated (Cas) systems in bacteria and archaea target foreign elements, such as bacteriophages and conjugative plasmids, through the incorporation of short sequences (termed spacers) from the foreign element into the CRISPR array, thereby allowing sequence-specific targeting of the invader. Thus, CRISPR-Cas systems are typically considered a microbial adaptive immune system. While many of these incorporated spacers match targets on bacteriophages and plasmids, a noticeable number are derived from chromosomal DNA. While usually lethal to the self-targeting bacteria, in certain circumstances, these self-targeting spacers can have profound effects in regard to microbial biology, including functions beyond adaptive immunity. In this minireview, we discuss recent studies that focus on the functions and consequences of CRISPR-Cas self-targeting, including reshaping of the host population, group behavior modification, and the potential applications of CRISPR-Cas self-targeting as a tool in microbial biotechnology. Understanding the effects of CRISPR-Cas self-targeting is vital to fully understanding the spectrum of function of these systems.
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24
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Price AA, Grakoui A, Weiss DS. Harnessing the Prokaryotic Adaptive Immune System as a Eukaryotic Antiviral Defense. Trends Microbiol 2016; 24:294-306. [PMID: 26852268 PMCID: PMC4808413 DOI: 10.1016/j.tim.2016.01.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 01/12/2016] [Accepted: 01/13/2016] [Indexed: 02/07/2023]
Abstract
Clustered, regularly interspaced, short palindromic repeats - CRISPR-associated (CRISPR-Cas) systems - are sequence-specific RNA-directed endonuclease complexes that bind and cleave nucleic acids. These systems evolved within prokaryotes as adaptive immune defenses to target and degrade nucleic acids derived from bacteriophages and other foreign genetic elements. The antiviral function of these systems has now been exploited to combat eukaryotic viruses throughout the viral life cycle. Here we discuss current advances in CRISPR-Cas9 technology as a eukaryotic antiviral defense.
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Affiliation(s)
- Aryn A Price
- Department of Microbiology and Immunology, Microbiology and Molecular Genetics Program, Emory University, Atlanta, GA 30329, USA; Emory Vaccine Center, Emory University, Atlanta, GA 30329, USA; Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA
| | - Arash Grakoui
- Emory Vaccine Center, Emory University, Atlanta, GA 30329, USA; Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA; Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia 30329, USA.
| | - David S Weiss
- Emory Vaccine Center, Emory University, Atlanta, GA 30329, USA; Yerkes National Primate Research Center, Emory University, Atlanta, GA 30329, USA; Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia 30329, USA.
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25
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Koonin EV, Wolf YI. Just how Lamarckian is CRISPR-Cas immunity: the continuum of evolvability mechanisms. Biol Direct 2016; 11:9. [PMID: 26912144 PMCID: PMC4765028 DOI: 10.1186/s13062-016-0111-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Accepted: 02/16/2016] [Indexed: 12/22/2022] Open
Abstract
The CRISPR-Cas system of prokaryotic adaptive immunity displays features of a mechanism for directional, Lamarckian evolution. Indeed, this system modifies a specific locus in a bacterial or archaeal genome by inserting a piece of foreign DNA into a CRISPR array which results in acquired, heritable resistance to the cognate selfish element. A key element of the Lamarckian scheme is the specificity and directionality of the mutational process whereby an environmental cue causes only mutations that provide specific adaptations to the original challenge. In the case of adaptive immunity, the specificity of mutations is equivalent to self-nonself discrimination. Recent studies on the CRISPR mechanism have shown that the levels of discrimination can substantially differ such that in some CRISPR-Cas variants incorporation of DNA is random whereas discrimination occurs by selection of cells that carry cognate inserts. In other systems, a higher level of specificity appears to be achieved via specialized mechanisms. These findings emphasize the continuity between random and directed mutations and the critical importance of evolved mechanisms that govern the mutational process.
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Affiliation(s)
- Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institute of Health, Bethesda, MD, 20894, USA.
| | - Yuri I Wolf
- National Center for Biotechnology Information, National Library of Medicine, National Institute of Health, Bethesda, MD, 20894, USA.
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26
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Pleška M, Qian L, Okura R, Bergmiller T, Wakamoto Y, Kussell E, Guet C. Bacterial Autoimmunity Due to a Restriction-Modification System. Curr Biol 2016; 26:404-9. [DOI: 10.1016/j.cub.2015.12.041] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Revised: 11/08/2015] [Accepted: 12/10/2015] [Indexed: 01/25/2023]
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