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Xiao W, Weissman JL, Johnson PLF. Ecological drivers of CRISPR immune systems. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.16.594560. [PMID: 38952799 PMCID: PMC11216370 DOI: 10.1101/2024.05.16.594560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/03/2024]
Abstract
CRISPR-Cas is the only known adaptive immune system of prokaryotes. It is a powerful defense system against mobile genetic elements such as bacteriophages. While CRISPR-Cas systems can be found throughout the prokaryotic tree of life, they are distributed unevenly across taxa and environments. Since adaptive immunity is more useful in environments where pathogens persist or reoccur, the density and/or diversity of the host/pathogen community may drive the uneven distribution of CRISPR system. We directly tested hypotheses connecting CRISPR incidence with prokaryotic density/diversity by analyzing 16S rRNA and metagenomic data from publicly available environmental sequencing projects. In terms of density, we found that CRISPR systems are significantly favored in lower abundance (less dense) taxa and disfavored in higher abundance taxa, at least in marine environments. When we extended this work to compare taxonomic diversity between samples, we found CRISPR system incidence strongly correlated with diversity in human oral environments. Together, these observations confirm that, at least in certain types of environments, the prokaryotic ecological context indeed plays a key role in selecting for CRISPR immunity. Importance 2Microbes must constantly defend themselves against viral pathogens, and a large proportion of prokaryotes do so using the highly effective CRISPR-Cas adaptive immune system. However, many prokaryotes do not. We investigated the ecological factors behind this uneven distribution of CRISPR-Cas immune systems in natural microbial populations. We found strong patterns linking CRISPR-Cas systems to prokaryotic density within ocean environments and to prokaryotic diversity within human oral environments. Our study validates previous within-lab experimental results that suggested these factors might be important and confirms that local environment and ecological context interact to select for CRISPR immunity.
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Mancilla-Rojano J, Flores V, Cevallos MA, Ochoa SA, Parra-Flores J, Arellano-Galindo J, Xicohtencatl-Cortes J, Cruz-Córdova A. A bioinformatic approach to identify confirmed and probable CRISPR-Cas systems in the Acinetobacter calcoaceticus- Acinetobacter baumannii complex genomes. Front Microbiol 2024; 15:1335997. [PMID: 38655087 PMCID: PMC11035748 DOI: 10.3389/fmicb.2024.1335997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 03/26/2024] [Indexed: 04/26/2024] Open
Abstract
Introduction The Acinetobacter calcoaceticus-Acinetobacter baumannii complex, or Acb complex, consists of six species: Acinetobacter baumannii, Acinetobacter calcoaceticus, Acinetobacter nosocomialis, Acinetobacter pittii, Acinetobacter seifertii, and Acinetobacter lactucae. A. baumannii is the most clinically significant of these species and is frequently related to healthcare-associated infections (HCAIs). Clustered regularly interspaced short palindromic repeat (CRISPR) arrays and associated genes (cas) constitute bacterial adaptive immune systems and function as variable genetic elements. This study aimed to conduct a genomic analysis of Acb complex genomes available in databases to describe and characterize CRISPR systems and cas genes. Methods Acb complex genomes available in the NCBI and BV-BRC databases, the identification and characterization of CRISPR-Cas systems were performed using CRISPRCasFinder, CRISPRminer, and CRISPRDetect. Sequence types (STs) were determined using the Oxford scheme and ribosomal multilocus sequence typing (rMLST). Prophages were identified using PHASTER and Prophage Hunter. Results A total of 293 genomes representing six Acb species exhibited CRISPR-related sequences. These genomes originate from various sources, including clinical specimens, animals, medical devices, and environmental samples. Sequence typing identified 145 ribosomal multilocus sequence types (rSTs). CRISPR-Cas systems were confirmed in 26.3% of the genomes, classified as subtypes I-Fa, I-Fb and I-Fv. Probable CRISPR arrays and cas genes associated with CRISPR-Cas subtypes III-A, I-B, and III-B were also detected. Some of the CRISPR-Cas systems are associated with genomic regions related to Cap4 proteins, and toxin-antitoxin systems. Moreover, prophage sequences were prevalent in 68.9% of the genomes. Analysis revealed a connection between these prophages and CRISPR-Cas systems, indicating an ongoing arms race between the bacteria and their bacteriophages. Furthermore, proteins associated with anti-CRISPR systems, such as AcrF11 and AcrF7, were identified in the A. baumannii and A. pittii genomes. Discussion This study elucidates CRISPR-Cas systems and defense mechanisms within the Acb complex, highlighting their diverse distribution and interactions with prophages and other genetic elements. This study also provides valuable insights into the evolution and adaptation of these microorganisms in various environments and clinical settings.
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Affiliation(s)
- Jetsi Mancilla-Rojano
- Posgrado en Ciencias Biológicas, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico, Mexico
- Laboratorio de Investigación en Bacteriología Intestinal, Unidad de Enfermedades Infecciosas, Hospital Infantil de México Federico Gómez, Secretaría de Salud, Mexico, Mexico
| | - Víctor Flores
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Miguel A. Cevallos
- Centro de Ciencias Genómicas, Programa de Genómica Evolutiva, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Sara A. Ochoa
- Laboratorio de Investigación en Bacteriología Intestinal, Unidad de Enfermedades Infecciosas, Hospital Infantil de México Federico Gómez, Secretaría de Salud, Mexico, Mexico
| | - Julio Parra-Flores
- Department of Nutrition and Public Health, Universidad del Bío-Bío, Chillán, Chile
| | - José Arellano-Galindo
- Unidad de Investigación en Enfermedades Infecciosas, Hospital Infantil de México Federico Gomez, Mexico, Mexico
| | - Juan Xicohtencatl-Cortes
- Laboratorio de Investigación en Bacteriología Intestinal, Unidad de Enfermedades Infecciosas, Hospital Infantil de México Federico Gómez, Secretaría de Salud, Mexico, Mexico
| | - Ariadnna Cruz-Córdova
- Posgrado en Ciencias Biológicas, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico, Mexico
- Laboratorio de Investigación en Bacteriología Intestinal, Unidad de Enfermedades Infecciosas, Hospital Infantil de México Federico Gómez, Secretaría de Salud, Mexico, Mexico
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Juszczuk-Kubiak E. Molecular Aspects of the Functioning of Pathogenic Bacteria Biofilm Based on Quorum Sensing (QS) Signal-Response System and Innovative Non-Antibiotic Strategies for Their Elimination. Int J Mol Sci 2024; 25:2655. [PMID: 38473900 DOI: 10.3390/ijms25052655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/21/2024] [Accepted: 02/22/2024] [Indexed: 03/14/2024] Open
Abstract
One of the key mechanisms enabling bacterial cells to create biofilms and regulate crucial life functions in a global and highly synchronized way is a bacterial communication system called quorum sensing (QS). QS is a bacterial cell-to-cell communication process that depends on the bacterial population density and is mediated by small signalling molecules called autoinducers (AIs). In bacteria, QS controls the biofilm formation through the global regulation of gene expression involved in the extracellular polymeric matrix (EPS) synthesis, virulence factor production, stress tolerance and metabolic adaptation. Forming biofilm is one of the crucial mechanisms of bacterial antimicrobial resistance (AMR). A common feature of human pathogens is the ability to form biofilm, which poses a serious medical issue due to their high susceptibility to traditional antibiotics. Because QS is associated with virulence and biofilm formation, there is a belief that inhibition of QS activity called quorum quenching (QQ) may provide alternative therapeutic methods for treating microbial infections. This review summarises recent progress in biofilm research, focusing on the mechanisms by which biofilms, especially those formed by pathogenic bacteria, become resistant to antibiotic treatment. Subsequently, a potential alternative approach to QS inhibition highlighting innovative non-antibiotic strategies to control AMR and biofilm formation of pathogenic bacteria has been discussed.
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Affiliation(s)
- Edyta Juszczuk-Kubiak
- Laboratory of Biotechnology and Molecular Engineering, Department of Microbiology, Prof. Wacław Dąbrowski Institute of Agricultural and Food Biotechnology-State Research Institute, Rakowiecka 36 Street, 02-532 Warsaw, Poland
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Yousefi MH, Wagemans J, Shekarforoush SS, Vallino M, Pozhydaieva N, Höfer K, Lavigne R, Hosseinzadeh S. Isolation and molecular characterization of the Salmonella Typhimurium orphan phage Arash. BMC Microbiol 2023; 23:297. [PMID: 37858092 PMCID: PMC10585845 DOI: 10.1186/s12866-023-03056-9] [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: 06/05/2023] [Accepted: 10/11/2023] [Indexed: 10/21/2023] Open
Abstract
The current threat of multidrug resistant strains necessitates development of alternatives to antibiotics such as bacteriophages. This study describes the isolation and characterization of a novel Salmonella Typhimurium phage 'Arash' from hospital wastewater in Leuven, Belgium. Arash has a myovirus morphology with a 95 nm capsid and a 140 nm tail. The host range of Arash is restricted to its isolation host. Approximately 86% of the phage particles are adsorbed to a host cell within 10 min. Arash has latent period of 65 min and burst size of 425 PFU/cell. Arash has a dsDNA genome of 180,819 bp with GC content of 53.02% with no similarities to any characterized phages, suggesting Arash as a novel species in the novel 'Arashvirus' genus. Arash carries no apparent lysogeny-, antibiotic resistance- nor virulence-related genes. Proteome analysis revealed 116 proteins as part of the mature phage particles of which 27 could be assigned a function. Therefore, the present findings shed light on the morphological, microbiological and genomic characteristics of Arash and suggest its potential application as therapeutic and/or biocontrol agent.
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Affiliation(s)
- Mohammad Hashem Yousefi
- Department of Food Hygiene and Public Health, School of Veterinary Medicine, Shiraz University, Shiraz, 71946- 84471, Iran
| | | | - Seyed Shahram Shekarforoush
- Department of Food Hygiene and Public Health, School of Veterinary Medicine, Shiraz University, Shiraz, 71946- 84471, Iran
| | - Marta Vallino
- Institute of Sustainable Plant Protection, National Research Council of Italy, Turin, 10135, Italy
| | - Nadiia Pozhydaieva
- Max Planck Institute for Terrestrial Microbiology, SYNMIKRO, Karl-von-Frisch-Strasse 16, Marburg, 35043, Germany
| | - Katharina Höfer
- Max Planck Institute for Terrestrial Microbiology, SYNMIKRO, Karl-von-Frisch-Strasse 16, Marburg, 35043, Germany
| | - Rob Lavigne
- Department of Biosystems, KU Leuven, Leuven, 3001, Belgium
| | - Saeid Hosseinzadeh
- Department of Food Hygiene and Public Health, School of Veterinary Medicine, Shiraz University, Shiraz, 71946- 84471, Iran.
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Wilhelm RC, Amsili JP, Kurtz KSM, van Es HM, Buckley DH. Ecological insights into soil health according to the genomic traits and environment-wide associations of bacteria in agricultural soils. ISME COMMUNICATIONS 2023; 3:1. [PMID: 37081121 PMCID: PMC9829723 DOI: 10.1038/s43705-022-00209-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 12/12/2022] [Accepted: 12/20/2022] [Indexed: 04/22/2023]
Abstract
Soil microbiomes are sensitive to current and previous soil conditions, and bacterial 'bioindicators' of biological, physical, and chemical soil properties have considerable potential for soil health assessment. However, the lack of ecological or physiological information for most soil microorganisms limits our ability to interpret the associations of bioindicators and, thus, their utility for guiding management. We identified bioindicators of tillage intensity and twelve soil properties used to rate soil health using a 16S rRNA gene-based survey of farmland across North America. We then inferred the genomic traits of bioindicators and evaluated their environment-wide associations (EWAS) with respect to agricultural management practice, disturbance, and plant associations with 89 studies from agroecosystems. Most bioindicators were either positively correlated with biological properties (e.g., organic matter) or negatively correlated with physical and chemical properties. Higher soil health ratings corresponded with smaller genome size and higher coding density, while lower ratings corresponded with larger genomes and higher rrn copy number. Community-weighted genome size explained most variation in health ratings. EWAS linked prominent bioindicators with the impacts of environmental disturbances. Our findings provide ecological insights into bioindicators of soil properties relevant to soil health management, illustrating the tight coupling of microbiome and soil function.
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Affiliation(s)
- Roland C Wilhelm
- School of Integrative Plant Sciences, Bradfield Hall, Cornell University, Ithaca, NY, 14853, USA.
| | - Joseph P Amsili
- School of Integrative Plant Sciences, Bradfield Hall, Cornell University, Ithaca, NY, 14853, USA
| | - Kirsten S M Kurtz
- School of Integrative Plant Sciences, Bradfield Hall, Cornell University, Ithaca, NY, 14853, USA
| | - Harold M van Es
- School of Integrative Plant Sciences, Bradfield Hall, Cornell University, Ithaca, NY, 14853, USA
| | - Daniel H Buckley
- School of Integrative Plant Sciences, Bradfield Hall, Cornell University, Ithaca, NY, 14853, USA
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Barchi Y, Philippe C, Chaïb A, Oviedo-Hernandez F, Claisse O, Le Marrec C. Phage Encounters Recorded in CRISPR Arrays in the Genus Oenococcus. Viruses 2022; 15:15. [PMID: 36680056 PMCID: PMC9867325 DOI: 10.3390/v15010015] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Revised: 12/10/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022] Open
Abstract
The Oenococcus genus comprises four recognized species, and members have been found in different types of beverages, including wine, kefir, cider and kombucha. In this work, we implemented two complementary strategies to assess whether oenococcal hosts of different species and habitats were connected through their bacteriophages. First, we investigated the diversity of CRISPR-Cas systems using a genome-mining approach, and CRISPR-endowed strains were identified in three species. A census of the spacers from the four identified CRISPR-Cas loci showed that each spacer space was mostly dominated by species-specific sequences. Yet, we characterized a limited records of potentially recent and also ancient infections between O. kitaharae and O. sicerae and phages of O. oeni, suggesting that some related phages have interacted in diverse ways with their Oenococcus hosts over evolutionary time. Second, phage-host interaction analyses were performed experimentally with a diversified panel of phages and strains. None of the tested phages could infect strains across the species barrier. Yet, some infections occurred between phages and hosts from distinct beverages in the O. oeni species.
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Affiliation(s)
| | | | | | | | | | - Claire Le Marrec
- UMR Oenologie 1366, Univ. Bordeaux, INRAE, Bordeaux INP, Bordeaux Sciences Agro, Institut des Sciences de la Vigne et du Vin, 33882 Villenave d’Ornon, France
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Soh JH, Balleza E, Abdul Rahim MN, Chan HM, Mohd Ali S, Chuah JKC, Edris S, Atef A, Bahieldin A, Ying JY, Sabir JS. CRISPR-based systems for sensitive and rapid on-site COVID-19 diagnostics. Trends Biotechnol 2022; 40:1346-1360. [PMID: 35871983 PMCID: PMC9174145 DOI: 10.1016/j.tibtech.2022.06.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 05/15/2022] [Accepted: 06/02/2022] [Indexed: 01/21/2023]
Abstract
The COVID-19 pandemic has strained healthcare systems. Sensitive, specific, and timely COVID-19 diagnosis is crucial for effective medical intervention and transmission control. RT-PCR is the most sensitive/specific, but requires costly equipment and trained personnel in centralized laboratories, which are inaccessible to resource-limited areas. Antigen rapid tests enable point-of-care (POC) detection but are significantly less sensitive/specific. CRISPR-Cas systems are compatible with isothermal amplification and dipstick readout, enabling sensitive/specific on-site testing. However, improvements in sensitivity and workflow complexity are needed to spur clinical adoption. We outline the mechanisms/strategies of major CRISPR-Cas systems, evaluate their on-site diagnostic capabilities, and discuss future research directions.
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Affiliation(s)
- Jun Hui Soh
- Cellbae Pte Ltd, 61 Science Park Road, The Galen, #03-07/08, Singapore 117525, Singapore
| | - Enrique Balleza
- Cellbae Pte Ltd, 61 Science Park Road, The Galen, #03-07/08, Singapore 117525, Singapore
| | | | - Hsi-Min Chan
- Cellbae Pte Ltd, 61 Science Park Road, The Galen, #03-07/08, Singapore 117525, Singapore
| | - Siswand Mohd Ali
- NanoBio Lab, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, The Nanos, Singapore 138669, Singapore,A*STAR Infectious Diseases Labs, A*STAR, 31 Biopolis Way, The Nanos, Singapore 138669, Singapore
| | | | - Sherif Edris
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, PO Box 80141, Jeddah 21589, Saudi Arabia,Centre of Excellence in Bionanoscience Research, King Abdulaziz University, Jeddah 21589, Saudi Arabia,Al-Borg Medical Laboratories, Al Borg Diagnostics, Jeddah, Saudi Arabia
| | - Ahmed Atef
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, PO Box 80141, Jeddah 21589, Saudi Arabia,Centre of Excellence in Bionanoscience Research, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Ahmed Bahieldin
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, PO Box 80141, Jeddah 21589, Saudi Arabia,Centre of Excellence in Bionanoscience Research, King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Jackie Y. Ying
- NanoBio Lab, Agency for Science, Technology and Research (A*STAR), 31 Biopolis Way, The Nanos, Singapore 138669, Singapore,A*STAR Infectious Diseases Labs, A*STAR, 31 Biopolis Way, The Nanos, Singapore 138669, Singapore,Institute of Materials Research and Engineering (IMRE), A*STAR, 31 Biopolis Way, The Nanos, Singapore 138669, Singapore,Correspondence:
| | - Jamal S.M. Sabir
- Department of Biological Sciences, Faculty of Science, King Abdulaziz University, PO Box 80141, Jeddah 21589, Saudi Arabia,Centre of Excellence in Bionanoscience Research, King Abdulaziz University, Jeddah 21589, Saudi Arabia,Correspondence:
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Demirci S, Essawi K, Germino-Watnick P, Liu X, Hakami W, Tisdale JF. Advances in CRISPR Delivery Methods: Perspectives and Challenges. CRISPR J 2022; 5:660-676. [PMID: 36260301 PMCID: PMC9835311 DOI: 10.1089/crispr.2022.0051] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
With the advent of new genome editing technologies and the emphasis placed on their optimization, the genetic and phenotypic correction of a plethora of diseases sit on the horizon. Ideally, genome editing approaches would provide long-term solutions through permanent disease correction instead of simply treating patients symptomatically. Although various editing machinery options exist, the clustered regularly interspaced short palindromic repeats (CRISPR)-Cas (CRISPR-associated protein) editing technique has emerged as the most popular due to its high editing efficiency, simplicity, and affordability. However, while CRISPR technology is gradually being perfected, optimization is futile without accessible, effective, and safe delivery to the desired cell or tissue. Therefore, it is important that scientists simultaneously focus on inventing and improving delivery modalities for editing machinery as well. In this review, we will discuss the critical details of viral and nonviral delivery systems, including payload, immunogenicity, efficacy in delivery, clinical application, and future directions.
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Affiliation(s)
- Selami Demirci
- Cellular and Molecular Therapeutics Branch, National Heart Lung and Blood Institutes (NHLBI), National Institutes of Health (NIH), Bethesda, Maryland, USA; and College of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia.,Address correspondence to: Selami Demirci, Cellular and Molecular Therapeutics Branch, National Heart Lung and Blood Institutes (NHLBI), National Institutes of Health (NIH), Bethesda, MD 20814, USA,
| | - Khaled Essawi
- Cellular and Molecular Therapeutics Branch, National Heart Lung and Blood Institutes (NHLBI), National Institutes of Health (NIH), Bethesda, Maryland, USA; and College of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia.,Department of Medical Laboratory Science, College of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia
| | - Paula Germino-Watnick
- Cellular and Molecular Therapeutics Branch, National Heart Lung and Blood Institutes (NHLBI), National Institutes of Health (NIH), Bethesda, Maryland, USA; and College of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia
| | - Xiong Liu
- Cellular and Molecular Therapeutics Branch, National Heart Lung and Blood Institutes (NHLBI), National Institutes of Health (NIH), Bethesda, Maryland, USA; and College of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia
| | - Waleed Hakami
- Department of Medical Laboratory Science, College of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia
| | - John F. Tisdale
- Cellular and Molecular Therapeutics Branch, National Heart Lung and Blood Institutes (NHLBI), National Institutes of Health (NIH), Bethesda, Maryland, USA; and College of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia.,Address correspondence to: John F. Tisdale, Cellular and Molecular Therapeutics Branch, National Heart Lung and Blood Institutes (NHLBI), National Institutes of Health (NIH), Bethesda, MD 20814, USA,
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Exploiting the Type I-B CRISPR Genome Editing System in Thermoanaerobacterium aotearoense SCUT27 and Engineering the Strain for Enhanced Ethanol Production. Appl Environ Microbiol 2022; 88:e0075122. [PMID: 35862665 PMCID: PMC9361813 DOI: 10.1128/aem.00751-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Thermoanaerobacterium aotearoense strain SCUT27 is a potential industrial biofuel-producing strain because of its broad substrate spectrum, especially the ability to co-use glucose and xylose. The bottleneck hindering the development of strain SCUT27 is the lack of selective markers for polygene manipulation in this thermophilic bacterium. In this study, the endogenous type I-B clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) system was developed for multiplex genome editing of strain SCUT27. The protospacer-adjacent motif was identified by in silico analysis and verified with orotidine-5'-phosphate decarboxylase (pyrF) or lactate dehydrogenase (ldh) as the editing target. The type I-B CRISPR/Cas system was functional in strain SCUT27 with 58.3% to 100% editing efficiency. A multiplex genome editing method based on thymidine kinase (tdk) as a negative selection marker was developed, and strain SCUT27/Δtdk/Δldh/ΔargR, in which ldh and the arginine repressor (argR) were knocked out successively, was successfully obtained. Strain SCUT27/Δtdk/Δldh/ΔargR exhibited prominent advantages over wild-type SCUT27 in ethanol production, with significantly improved ability to metabolize xylose. IMPORTANCE Thermophilic microbes have attracted great attention as potential candidates for production of biofuels and chemicals from lignocellulose because of their thermal tolerance and wide substrate spectra. The ability to edit multiple genes using the native type I-B CRISPR/Cas system would speed up engineering of Thermoanaerobacterium aotearoense strain SCUT27 for higher ethanol production from lignocellulosic hydrolysates. Here, we produced a mutant strain, T. aotearoense SCUT27/Δtdk/Δldh/ΔargR, using the native CRISPR/Cas system. The engineered strain showed satisfactory performance with improved ethanol productivity from various lignocellulosic hydrolysates. Our data lay the foundations for development of this thermophilic microbe into an excellent ethanol producer using lignocellulosic hydrolysates. The methods described here may also provide a reference to develop multigene editing methods for other microorganisms.
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Chernyak BV, Lyamzaev KG, Mulkidjanian AY. Innate Immunity as an Executor of the Programmed Death of Individual Organisms for the Benefit of the Entire Population. Int J Mol Sci 2021; 22:ijms222413480. [PMID: 34948277 PMCID: PMC8704876 DOI: 10.3390/ijms222413480] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 12/11/2021] [Accepted: 12/13/2021] [Indexed: 11/19/2022] Open
Abstract
In humans, over-activation of innate immunity in response to viral or bacterial infections often causes severe illness and death. Furthermore, similar mechanisms related to innate immunity can cause pathogenesis and death in sepsis, massive trauma (including surgery and burns), ischemia/reperfusion, some toxic lesions, and viral infections including COVID-19. Based on the reviewed observations, we suggest that such severe outcomes may be manifestations of a controlled suicidal strategy protecting the entire population from the spread of pathogens and from dangerous pathologies rather than an aberrant hyperstimulation of defense responses. We argue that innate immunity may be involved in the implementation of an altruistic programmed death of an organism aimed at increasing the well-being of the whole community. We discuss possible ways to suppress this atavistic program by interfering with innate immunity and suggest that combating this program should be a major goal of future medicine.
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Affiliation(s)
- Boris V. Chernyak
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119992 Moscow, Russia;
- Correspondence: (B.V.C.); (A.Y.M.)
| | - Konstantin G. Lyamzaev
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119992 Moscow, Russia;
| | - Armen Y. Mulkidjanian
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119992 Moscow, Russia;
- School of Bioengineering and Bioinformatics, Lomonosov Moscow State University, 119992 Moscow, Russia
- Department of Physics, Osnabrueck University, D-49069 Osnabrueck, Germany
- Correspondence: (B.V.C.); (A.Y.M.)
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Gómez-Godínez LJ, Martínez-Romero E, Banuelos J, Arteaga-Garibay RI. Tools and challenges to exploit microbial communities in agriculture. CURRENT RESEARCH IN MICROBIAL SCIENCES 2021; 2:100062. [PMID: 34841352 PMCID: PMC8610360 DOI: 10.1016/j.crmicr.2021.100062] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 08/12/2021] [Accepted: 08/18/2021] [Indexed: 12/13/2022] Open
Abstract
Plants contain diverse microbial communities. The associated microorganisms confer advantages to the host plant, which include growth promotion, nutrient absorption, stress tolerance, and pathogen and disease resistance. In this review, we explore how agriculture is implementing the use of microbial inoculants (single species or consortia) to improve crop yields, and discuss current strategies to study plant-associated microorganisms and how their diversity varies under unconventional agriculture. It is predicted that microbial inoculation will continue to be used in agriculture.
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Affiliation(s)
- Lorena Jacqueline Gómez-Godínez
- Laboratorio de Recursos Genéticos Microbianos, Centro Nacional de Recursos Genéticos. Instituto Nacional de Investigación Forestales, Agrícolas y Pecuarios. Boulevard de la Biodiversidad 400, Rancho las Cruces, C.P. 47600. Tepatitlán de Morelos, Jalisco, México
| | - Esperanza Martínez-Romero
- Centro de Ciencias genómicas, Universidad Nacional Autónoma de México Campus Morelos, Cuernavaca, Morelos México
| | - Jacob Banuelos
- Laboratorio de Organismos Benéficos, Facultad de Ciencias Agrícolas, Universidad Veracruzana. Circuito Aguirre Beltrán SN, Col. Universitaria, CP 91000, Xalapa, Veracruz, México
| | - Ramón I. Arteaga-Garibay
- Laboratorio de Recursos Genéticos Microbianos, Centro Nacional de Recursos Genéticos. Instituto Nacional de Investigación Forestales, Agrícolas y Pecuarios. Boulevard de la Biodiversidad 400, Rancho las Cruces, C.P. 47600. Tepatitlán de Morelos, Jalisco, México
- Corresponding authors.
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12
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Weissman JL, Alseth EO, Meaden S, Westra ER, Fuhrman JA. Immune lag is a major cost of prokaryotic adaptive immunity during viral outbreaks. Proc Biol Sci 2021; 288:20211555. [PMID: 34666523 PMCID: PMC8527200 DOI: 10.1098/rspb.2021.1555] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Clustered regularly interspaced short palindromic repeat (CRISPR)-Cas adaptive immune systems enable bacteria and archaea to efficiently respond to viral pathogens by creating a genomic record of previous encounters. These systems are broadly distributed across prokaryotic taxa, yet are surprisingly absent in a majority of organisms, suggesting that the benefits of adaptive immunity frequently do not outweigh the costs. Here, combining experiments and models, we show that a delayed immune response which allows viruses to transiently redirect cellular resources to reproduction, which we call ‘immune lag’, is extremely costly during viral outbreaks, even to completely immune hosts. Critically, the costs of lag are only revealed by examining the early, transient dynamics of a host–virus system occurring immediately after viral challenge. Lag is a basic parameter of microbial defence, relevant to all intracellular, post-infection antiviral defence systems, that has to-date been largely ignored by theoretical and experimental treatments of host-phage systems.
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Affiliation(s)
- Jake L Weissman
- Department of Biological Sciences-Marine and Environmental Biology, University of Southern California, Los Angeles, CA, USA
| | - Ellinor O Alseth
- Environment and Sustainability Institute, Biosciences, University of Exeter, Penryn Campus, Penryn, UK
| | - Sean Meaden
- Environment and Sustainability Institute, Biosciences, University of Exeter, Penryn Campus, Penryn, UK
| | - Edze R Westra
- Environment and Sustainability Institute, Biosciences, University of Exeter, Penryn Campus, Penryn, UK
| | - Jed A Fuhrman
- Department of Biological Sciences-Marine and Environmental Biology, University of Southern California, Los Angeles, CA, USA
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13
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Islam MT, Nasreen T, Kirchberger PC, Liang KYH, Orata FD, Johura FT, Hussain NAS, Im MS, Tarr CL, Alam M, Boucher YF. Population Analysis of Vibrio cholerae in Aquatic Reservoirs Reveals a Novel Sister Species ( Vibrio paracholerae sp. nov.) with a History of Association with Humans. Appl Environ Microbiol 2021; 87:e0042221. [PMID: 34132593 PMCID: PMC8357300 DOI: 10.1128/aem.00422-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Accepted: 06/04/2021] [Indexed: 12/12/2022] Open
Abstract
Most efforts to understand the biology of Vibrio cholerae have focused on a single group, the pandemic-generating lineage harboring the strains responsible for all known cholera pandemics. Consequently, little is known about the diversity of this species in its native aquatic environment. To understand the differences in the V. cholerae populations inhabiting regions with a history of cholera cases and those lacking such a history, a comparative analysis of population composition was performed. Little overlap was found in lineage compositions between those in Dhaka, Bangladesh (where cholera is endemic), located in the Ganges Delta, and those in Falmouth, MA (no known history of cholera), a small coastal town on the United States east coast. The most striking difference was the presence of a group of related lineages at high abundance in Dhaka, which was completely absent from Falmouth. Phylogenomic analysis revealed that these lineages form a cluster at the base of the phylogeny for the V. cholerae species and were sufficiently differentiated genetically and phenotypically to form a novel species. A retrospective search revealed that strains from this species have been anecdotally found from around the world and were isolated as early as 1916 from a British soldier in Egypt suffering from choleraic diarrhea. In 1935, Gardner and Venkatraman unofficially referred to a member of this group as Vibrio paracholerae. In recognition of this earlier designation, we propose the name Vibrio paracholerae sp. nov. for this bacterium. Genomic analysis suggests a link with human populations for this novel species and substantial interaction with its better-known sister species. IMPORTANCE Cholera continues to remain a major public health threat around the globe. Understanding the ecology, evolution, and environmental adaptation of the causative agent (Vibrio cholerae) and tracking the emergence of novel lineages with pathogenic potential are essential to combat the problem. In this study, we investigated the population dynamics of Vibrio cholerae in an inland locality, which is known as endemic for cholera, and compared them with those of a cholera-free coastal location. We found the consistent presence of the pandemic-generating lineage of V. cholerae in Dhaka, where cholera is endemic, and an exclusive presence of a lineage phylogenetically distinct from other V. cholerae lineages. Our study suggests that this lineage represents a novel species that has pathogenic potential and a human link to its environmental abundance. The possible association with human populations and coexistence and interaction with toxigenic V. cholerae in the natural environment make this potential human pathogen an important subject for future studies.
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Affiliation(s)
| | - Tania Nasreen
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Paul C. Kirchberger
- Department of Integrative Biology, University of Texas at Austin, Austin, Texas, USA
| | - Kevin Y. H. Liang
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Fabini D. Orata
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Fatema-Tuz Johura
- Infectious Diseases Division, International Centre for Diarrheal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | - Nora A. S. Hussain
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Monica S. Im
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Cheryl L. Tarr
- National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Munirul Alam
- Infectious Diseases Division, International Centre for Diarrheal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | - Yann F. Boucher
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore
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14
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Singh P, Ali SA. Impact of CRISPR-Cas9-Based Genome Engineering in Farm Animals. Vet Sci 2021; 8:122. [PMID: 34209174 PMCID: PMC8309983 DOI: 10.3390/vetsci8070122] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/21/2021] [Accepted: 06/22/2021] [Indexed: 12/26/2022] Open
Abstract
Humans are sorely over-dependent on livestock for their daily basic need of food in the form of meat, milk, and eggs. Therefore, genetic engineering and transgenesis provide the opportunity for more significant gains and production in a short span of time. One of the best strategies is the genetic alteration of livestock to enhance the efficiency of food production (e.g., meat and milk), animal health, and welfare (animal population and disease). Moreover, genome engineering in the bovine is majorly focused on subjects such as disease resistance (e.g., tuberculosis), eradicate allergens (e.g., beta-lactoglobulin knock-out), products generation (e.g., meat from male and milk from female), male or female birth specifically (animal sexing), the introduction of valuable traits (e.g., stress tolerance and disease resistance) and their wellbeing (e.g., hornlessness). This review addressed the impressive genome engineering method CRISPR, its fundamental principle for generating highly efficient target-specific guide RNA, and the accompanying web-based tools. However, we have covered the remarkable roadmap of the CRISPR method from its conception to its use in cattle. Additionally, we have updated the comprehensive information on CRISPR-based gene editing in cattle.
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Affiliation(s)
| | - Syed Azmal Ali
- Proteomics and Cell Biology Lab, Animal Biotechnology Center, ICAR-National Dairy Research Institute, Karnal 132001, India;
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15
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Abstract
The evolution of many microbes and pathogens, including circulating viruses such as seasonal influenza, is driven by immune pressure from the host population. In turn, the immune systems of infected populations get updated, chasing viruses even farther away. Quantitatively understanding how these dynamics result in observed patterns of rapid pathogen and immune adaptation is instrumental to epidemiological and evolutionary forecasting. Here we present a mathematical theory of coevolution between immune systems and viruses in a finite-dimensional antigenic space, which describes the cross-reactivity of viral strains and immune systems primed by previous infections. We show the emergence of an antigenic wave that is pushed forward and canalized by cross-reactivity. We obtain analytical results for shape, speed, and angular diffusion of the wave. In particular, we show that viral-immune coevolution generates an emergent timescale, the persistence time of the wave's direction in antigenic space, which can be much longer than the coalescence time of the viral population. We compare these dynamics to the observed antigenic turnover of influenza strains, and we discuss how the dimensionality of antigenic space impacts the predictability of the evolutionary dynamics. Our results provide a concrete and tractable framework to describe pathogen-host coevolution.
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16
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Seok H, Deng R, Cowan DB, Wang DZ. Application of CRISPR-Cas9 gene editing for congenital heart disease. Clin Exp Pediatr 2021; 64:269-279. [PMID: 33677855 PMCID: PMC8181018 DOI: 10.3345/cep.2020.02096] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Accepted: 02/15/2021] [Indexed: 12/26/2022] Open
Abstract
Clustered regularly interspaced short palindromic repeats and CRISPR-associated protein 9 (CRISPR-Cas9) is an ancient prokaryotic defense system that precisely cuts foreign genomic DNA under the control of a small number of guide RNAs. The CRISPR-Cas9 system facilitates efficient double-stranded DNA cleavage that has been recently adopted for genome editing to create or correct inherited genetic mutations causing disease. Congenital heart disease (CHD) is generally caused by genetic mutations such as base substitutions, deletions, and insertions, which result in diverse developmental defects and remains a leading cause of birth defects. Pediatric CHD patients exhibit a spectrum of cardiac abnormalities such as septal defects, valvular defects, and abnormal chamber development. CHD onset occurs during the prenatal period and often results in early lethality during childhood. Because CRISPR-Cas9-based genome editing technology has gained considerable attention for its potential to prevent and treat diseases, we will review the CRISPR-Cas9 system as a genome editing tool and focus on its therapeutic application for CHD.
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Affiliation(s)
- Heeyoung Seok
- Department of Life Sciences, Korea University, Seoul, Korea
| | - Rui Deng
- Department of Cardiology, Boston Children's Hospital, Boston, MA, USA.,Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Douglas B Cowan
- Department of Cardiology, Boston Children's Hospital, Boston, MA, USA.,Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Da-Zhi Wang
- Department of Cardiology, Boston Children's Hospital, Boston, MA, USA.,Department of Pediatrics, Harvard Medical School, Boston, MA, USA
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17
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Zhang L, Kang WJ, Zhu L, Xu LJ, Guo C, Zhang XH, Liu QH, Ma L. Emergence of Invasive Serotype Ib Sequence Type 10 Group B Streptococcus Disease in Chinese Infants Is Driven by a Tetracycline-Sensitive Clone. Front Cell Infect Microbiol 2021; 11:642455. [PMID: 34055663 PMCID: PMC8162377 DOI: 10.3389/fcimb.2021.642455] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 04/26/2021] [Indexed: 01/31/2023] Open
Abstract
Background Group B streptococcus (GBS) is a leading cause of serious infections in infants. The extensive use of tetracycline has led to the selection of specific resistant and infectious GBS clones. The sequence type (ST) 10 GBS strain, causing invasive infections in infants, is becoming prevalent in China. We aimed to understand the clinical and microbiological characteristics of this GBS strain. Methods We conducted a retrospective study on infants with invasive GBS disease from the largest women’s and children’s medical center in Shanxi and collected data between January 2017 and October 2020. GBS isolates were analyzed by capsule serotyping, genotyping, antibiotic resistance, and surface protein genes. Results All ST10 isolates belonged to serotype Ib; type Ib/ST10 strains were responsible for 66.7% (14/21, P < 0.05) of infant invasive GBS infections during the period and all resulted in late-onset (LOD) and late LOD disease (14/14). Infants with type Ib/ST10 GBS disease had significantly higher rates of meningitis (9/14, 64.3%, p < 0.05) and clinical complications (5/14, 35.7%, p < 0.05). The Ib/ST10 GBS isolates had limited genetic diversity, clustered in the CC10/bca/PI-1 + PI-2a genetic lineage, showed resistance to erythromycin, lincomycin, and fluoroquinolones and sensitivity to tetracycline, and possessed genes ermT, ermB, and amino acid changes in gyrA and parC. Conclusions The probable clonal expansion can result in severe infections in infants and ongoing emergence of multi-drug resistant isolates. Continued monitoring for type Ib/ST10 GBS infections is warranted.
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Affiliation(s)
- Li Zhang
- Department of Clinical Laboratory, Shanxi Children's Hospital Shanxi Maternal and Child Health Hospital, Taiyuan, China
| | - Wen-Juan Kang
- Department of Clinical Laboratory, Shanxi Children's Hospital Shanxi Maternal and Child Health Hospital, Taiyuan, China
| | - Lei Zhu
- Department of Clinical Laboratory, Shanxi Children's Hospital Shanxi Maternal and Child Health Hospital, Taiyuan, China
| | - Li-Jun Xu
- Department of Clinical Laboratory, Shanxi Children's Hospital Shanxi Maternal and Child Health Hospital, Taiyuan, China
| | - Chao Guo
- Department of Clinical Laboratory, Shanxi Children's Hospital Shanxi Maternal and Child Health Hospital, Taiyuan, China
| | - Xin-Hua Zhang
- Department of Neonatology Department, Shanxi Children's Hospital Shanxi Maternal and Child Health Hospital, Taiyuan, China
| | - Qing-Hua Liu
- Department of Pathophysiology, Shanxi Medical University, Taiyuan, China
| | - Lan Ma
- Department of Clinical Laboratory, Shanxi Children's Hospital Shanxi Maternal and Child Health Hospital, Taiyuan, China
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18
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Dion MB, Plante PL, Zufferey E, Shah SA, Corbeil J, Moineau S. Streamlining CRISPR spacer-based bacterial host predictions to decipher the viral dark matter. Nucleic Acids Res 2021; 49:3127-3138. [PMID: 33677572 PMCID: PMC8034630 DOI: 10.1093/nar/gkab133] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 02/15/2021] [Accepted: 02/17/2021] [Indexed: 12/26/2022] Open
Abstract
Thousands of new phages have recently been discovered thanks to viral metagenomics. These phages are extremely diverse and their genome sequences often do not resemble any known phages. To appreciate their ecological impact, it is important to determine their bacterial hosts. CRISPR spacers can be used to predict hosts of unknown phages, as spacers represent biological records of past phage–bacteria interactions. However, no guidelines have been established to standardize host prediction based on CRISPR spacers. Additionally, there are no tools that use spacers to perform host predictions on large viral datasets. Here, we developed a set of tools that includes all the necessary steps for predicting the hosts of uncharacterized phages. We created a database of >11 million spacers and a program to execute host predictions on large viral datasets. Our host prediction approach uses biological criteria inspired by how CRISPR–Cas naturally work as adaptive immune systems, which make the results easy to interpret. We evaluated the performance using 9484 phages with known hosts and obtained a recall of 49% and a precision of 69%. We also found that this host prediction method yielded higher performance for phages that infect gut-associated bacteria, suggesting it is well suited for gut-virome characterization.
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Affiliation(s)
- Moïra B Dion
- Département de biochimie, de microbiologie et de bio-informatique, Faculté des sciences et de génie, Université Laval, Québec City, Québec G1V 0A6, Canada.,Groupe de recherche en écologie buccale, Faculté de médecine dentaire, Université Laval, Québec City, Québec G1V 0A6, Canada
| | - Pier-Luc Plante
- Centre de recherche en infectiologie de l'Université Laval, Axe maladies infectieuses et immunitaires, Centre de Recherche du CHU de Québec-Université Laval, Québec City, Québec G1V 4G2, Canada.,Centre de recherche en données massives, Université Laval, Québec City, Québec G1V 0A6, Canada.,Département de médecine moléculaire, Faculté de Médecine, Université Laval, Québec City, Québec G1V 0A6, Canada
| | - Edwige Zufferey
- Département de biochimie, de microbiologie et de bio-informatique, Faculté des sciences et de génie, Université Laval, Québec City, Québec G1V 0A6, Canada.,Groupe de recherche en écologie buccale, Faculté de médecine dentaire, Université Laval, Québec City, Québec G1V 0A6, Canada
| | - Shiraz A Shah
- COPSAC, Copenhagen Prospective Studies on Asthma in Childhood, Herlev and Gentofte Hospital, University of Copenhagen, Gentofte 2820, Denmark
| | - Jacques Corbeil
- Centre de recherche en infectiologie de l'Université Laval, Axe maladies infectieuses et immunitaires, Centre de Recherche du CHU de Québec-Université Laval, Québec City, Québec G1V 4G2, Canada.,Centre de recherche en données massives, Université Laval, Québec City, Québec G1V 0A6, Canada.,Département de médecine moléculaire, Faculté de Médecine, Université Laval, Québec City, Québec G1V 0A6, Canada
| | - Sylvain Moineau
- Département de biochimie, de microbiologie et de bio-informatique, Faculté des sciences et de génie, Université Laval, Québec City, Québec G1V 0A6, Canada.,Groupe de recherche en écologie buccale, Faculté de médecine dentaire, Université Laval, Québec City, Québec G1V 0A6, Canada.,Félix d'Hérelle Reference Center for Bacterial Viruses, Université Laval, Québec City, Québec G1V 0A6, Canada
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19
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Wheatley RM, MacLean RC. CRISPR-Cas systems restrict horizontal gene transfer in Pseudomonas aeruginosa. THE ISME JOURNAL 2021; 15:1420-1433. [PMID: 33349652 PMCID: PMC8105352 DOI: 10.1038/s41396-020-00860-3] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 11/06/2020] [Accepted: 11/26/2020] [Indexed: 11/29/2022]
Abstract
CRISPR-Cas systems provide bacteria and archaea with an adaptive immune system that targets foreign DNA. However, the xenogenic nature of immunity provided by CRISPR-Cas raises the possibility that these systems may constrain horizontal gene transfer. Here we test this hypothesis in the opportunistic pathogen Pseudomonas aeruginosa, which has emerged as an important model system for understanding CRISPR-Cas function. Across the diversity of P. aeruginosa, active CRISPR-Cas systems are associated with smaller genomes and higher GC content, suggesting that CRISPR-Cas inhibits the acquisition of foreign DNA. Although phage is the major target of CRISPR-Cas spacers, more than 80% of isolates with an active CRISPR-Cas system have spacers that target integrative conjugative elements (ICE) or the conserved conjugative transfer machinery used by plasmids and ICE. Consistent with these results, genomes containing active CRISPR-Cas systems harbour a lower abundance of both prophage and ICE. Crucially, spacers in genomes with active CRISPR-Cas systems map to ICE and phage that are integrated into the chromosomes of closely related genomes lacking CRISPR-Cas immunity. We propose that CRISPR-Cas acts as an important constraint to horizontal gene transfer, and the evolutionary mechanisms that ensure its maintenance or drive its loss are key to the ability of this pathogen to adapt to new niches and stressors.
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Affiliation(s)
| | - R Craig MacLean
- Department of Zoology, University of Oxford, Oxford, OX1 3PS, UK
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20
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Guerrero LD, Pérez MV, Orellana E, Piuri M, Quiroga C, Erijman L. Long-run bacteria-phage coexistence dynamics under natural habitat conditions in an environmental biotechnology system. THE ISME JOURNAL 2021; 15:636-648. [PMID: 33067586 PMCID: PMC8027832 DOI: 10.1038/s41396-020-00802-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 09/21/2020] [Accepted: 10/01/2020] [Indexed: 01/30/2023]
Abstract
Bacterial viruses are widespread and abundant across natural and engineered habitats. They influence ecosystem functioning through interactions with their hosts. Laboratory studies of phage-host pairs have advanced our understanding of phenotypic and genetic diversification in bacteria and phages. However, the dynamics of phage-host interactions have been seldom recorded in complex natural environments. We conducted an observational metagenomic study of the dynamics of interaction between Gordonia and their phages using a three-year data series of samples collected from a full-scale wastewater treatment plant. The aim was to obtain a comprehensive picture of the coevolution dynamics in naturally evolving populations at relatively high time resolution. Coevolution was followed by monitoring changes over time in the CRISPR loci of Gordonia metagenome-assembled genome, and reciprocal changes in the viral genome. Genome-wide analysis indicated low strain variability of Gordonia, and almost clonal conservation of the trailer end of the CRISPR loci. Incorporation of newer spacers gave rise to multiple coexisting bacterial populations. The host population carrying a shorter CRISPR locus that contain only ancestral spacers, which has not acquired newer spacers against the coexisting phages, accounted for more than half of the total host abundance in the majority of samples. Phages genome co-evolved by introducing directional changes, with no preference for mutations within the protospacer and PAM regions. Metagenomic reconstruction of time-resolved variants of host and viral genomes revealed how the complexity at the population level has important consequences for bacteria-phage coexistence.
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Affiliation(s)
- Leandro D. Guerrero
- grid.423606.50000 0001 1945 2152Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr Héctor N. Torres” (INGEBI-CONICET), Vuelta de Obligado 2490, C1428ADN Buenos Aires, Argentina
| | - María V. Pérez
- grid.423606.50000 0001 1945 2152Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr Héctor N. Torres” (INGEBI-CONICET), Vuelta de Obligado 2490, C1428ADN Buenos Aires, Argentina ,Agua y Saneamientos Argentinos S.A., Tucumán 752, C1049APP Buenos Aires, Argentina
| | - Esteban Orellana
- grid.423606.50000 0001 1945 2152Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr Héctor N. Torres” (INGEBI-CONICET), Vuelta de Obligado 2490, C1428ADN Buenos Aires, Argentina
| | - Mariana Piuri
- Departamento de Química Biológica, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, CONICET, Intendente Güiraldes 2160, C1428EGA Buenos Aires, Argentina
| | - Cecilia Quiroga
- Instituto de Investigaciones en Microbiología y Parasitología Médica (IMPaM), Facultad de Medicina, Universidad de Buenos Aires, CONICET, Paraguay 2155, C1121ABG Buenos Aires, Argentina
| | - Leonardo Erijman
- grid.423606.50000 0001 1945 2152Instituto de Investigaciones en Ingeniería Genética y Biología Molecular “Dr Héctor N. Torres” (INGEBI-CONICET), Vuelta de Obligado 2490, C1428ADN Buenos Aires, Argentina ,grid.7345.50000 0001 0056 1981Departamento de Fisiología, Biología Molecular y Celular, Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires, Intendente Güiraldes 2160s, C1428EGA Buenos Aires, Argentina
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21
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Pavlova YS, Paez-Espino D, Morozov AY, Belalov IS. Searching for fat tails in CRISPR-Cas systems: Data analysis and mathematical modeling. PLoS Comput Biol 2021; 17:e1008841. [PMID: 33770071 PMCID: PMC8026048 DOI: 10.1371/journal.pcbi.1008841] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 04/07/2021] [Accepted: 03/01/2021] [Indexed: 12/28/2022] Open
Abstract
Understanding CRISPR-Cas systems-the adaptive defence mechanism that about half of bacterial species and most of archaea use to neutralise viral attacks-is important for explaining the biodiversity observed in the microbial world as well as for editing animal and plant genomes effectively. The CRISPR-Cas system learns from previous viral infections and integrates small pieces from phage genomes called spacers into the microbial genome. The resulting library of spacers collected in CRISPR arrays is then compared with the DNA of potential invaders. One of the most intriguing and least well understood questions about CRISPR-Cas systems is the distribution of spacers across the microbial population. Here, using empirical data, we show that the global distribution of spacer numbers in CRISPR arrays across multiple biomes worldwide typically exhibits scale-invariant power law behaviour, and the standard deviation is greater than the sample mean. We develop a mathematical model of spacer loss and acquisition dynamics which fits observed data from almost four thousand metagenomes well. In analogy to the classical 'rich-get-richer' mechanism of power law emergence, the rate of spacer acquisition is proportional to the CRISPR array size, which allows a small proportion of CRISPRs within the population to possess a significant number of spacers. Our study provides an alternative explanation for the rarity of all-resistant super microbes in nature and why proliferation of phages can be highly successful despite the effectiveness of CRISPR-Cas systems.
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Affiliation(s)
- Yekaterina S. Pavlova
- Mathematics Department, Palomar College, San Marcos, California, United States of America
| | - David Paez-Espino
- Department of Energy, Joint Genome Institute, Walnut Creek, California, United States of America
- Mammoth BioSciences, South San Francisco, California, United States of America
| | - Andrew Yu. Morozov
- School of Mathematics and Actuarial Science, University of Leicester, Leicester, United Kingdom
- Institute of Ecology and Evolution, Russian Academy of Sciences, Moscow, Russia
| | - Ilya S. Belalov
- Laboratory of Microbial Viruses, Winogradsky Institute of Microbiology, Research Center of Biotechnology RAS, Moscow, Russia
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22
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Meziti A, Nikouli E, Hatt JK, Konstantinidis KT, Kormas KA. Time series metagenomic sampling of the Thermopyles, Greece, geothermal springs reveals stable microbial communities dominated by novel sulfur-oxidizing chemoautotrophs. Environ Microbiol 2021; 23:3710-3726. [PMID: 33350070 DOI: 10.1111/1462-2920.15373] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 12/19/2020] [Indexed: 11/29/2022]
Abstract
Geothermal springs are essentially unaffected by environmental conditions aboveground as they are continuously supplied with subsurface water with little variability in chemistry. Therefore, changes in their microbial community composition and function, especially over a long period, are expected to be limited but this assumption has not yet been rigorously tested. Toward closing this knowledge gap, we applied whole metagenome sequencing to 17 water samples collected between 2010 and 2016 from the Thermopyles sulfur-rich geothermal springs in central Greece. As revealed by 16S rRNA gene fragments recovered in the metagenomes, Epsilonproteobacteria-related operational taxonomic units (OTUs) dominated most samples and grouping of samples based on OTU abundances exhibited no apparent seasonal pattern. Similarities between samples regarding functional gene content were high, with all samples sharing >70% similarity in functional pathways. These community-wide patterns were further confirmed by analysis of metagenome-assembled genomes (MAGs), which showed that novel species and genera of the chemoautotrophic Campylobacterales order dominated the springs. These MAGs carried different pathways for thiosulfate or sulfide oxidation coupled to carbon fixation pathways. Overall, our study showed that even in the long term, functions of microbial communities in a moderately hot terrestrial spring remain stable, presumably driving the corresponding stability in community structure.
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Affiliation(s)
- A Meziti
- Department of Ichthyology and Aquatic Environment, University of Thessaly, Volos, 38446, Greece.,School of Civil and Environmental Engineering, Georgia Institute of Technology, Ford Environmental Science and Technology Building, 311 Ferst Drive, Atlanta, GA, 30332, USA
| | - E Nikouli
- Department of Ichthyology and Aquatic Environment, University of Thessaly, Volos, 38446, Greece.,School of Civil and Environmental Engineering, Georgia Institute of Technology, Ford Environmental Science and Technology Building, 311 Ferst Drive, Atlanta, GA, 30332, USA
| | - J K Hatt
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Ford Environmental Science and Technology Building, 311 Ferst Drive, Atlanta, GA, 30332, USA
| | - K T Konstantinidis
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Ford Environmental Science and Technology Building, 311 Ferst Drive, Atlanta, GA, 30332, USA.,School of Biological Sciences, Georgia Institute of Technology, Ford Environmental Sciences and Technology Building, 311 Ferst Drive, Atlanta, GA, 30332, USA
| | - K A Kormas
- Department of Ichthyology and Aquatic Environment, University of Thessaly, Volos, 38446, Greece
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23
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Ruiz-Hernández UE, Pelcastre-Rodriguez LI, Cabrero-Martínez OA, Hernández-Cortez C, Castro-Escarpulli G. Analysis of CRISPR-Cas systems in Gardnerella suggests its potential role in the mechanisms of bacterial vaginosis. Comput Biol Chem 2020; 89:107381. [PMID: 33002715 DOI: 10.1016/j.compbiolchem.2020.107381] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 09/16/2020] [Accepted: 09/18/2020] [Indexed: 10/23/2022]
Abstract
Bacterial vaginosis (BV) is the principal cause of vaginal discharge among women, and it can lead to many comorbidities with a negative impact in women's daily activities. Despite the fact that the pathophysiological process of BV remains unclear, great advances had been achieved in determining consequences of the shift in the vaginal community, and it was defined that Gardnerella spp., plays a key role in the pathogenesis of BV. Interactions of vaginal phage communities and bacterial hosts may be relevant in eubiosis/dysbiosis states, so defense mechanisms in Gardnerella spp., against phage infections could be relevant in BV development. In this study, we analyzed CRISPR-Cas systems among the 13 Gardnerella species recently classified, considering that these systems act as prokaryotic immune systems against phages, plasmids, and other mobile genetic elements. In silico analyses for CRISPR-Cas systems mining over the 81 Gardnerella spp., strains genomes analyzed led to the identification of subtypes I-E and II-C. Spacers analyses showed a hypervariable region across species, providing a high resolution level in order to distinguish clonality in strains, which was supported with phylogenomic analyses based on Virtual Genomic Fingerprinting. Moreover, most of the spacers revealed interactions between Gardnerella spp., strains and prophages over the genus. Furthermore, virulence traits of the 13 species showed insights of potential niche specificity in the vaginal microbiome. Overall, our results suggest that the CRISPR-Cas systems in the genus Gardnerella may play an important role in the mechanisms of the development and maintenance of BV, considering that the Gardnerella species occupies different niches in the vaginal community; in addition, spacer sequences can be used for genotyping studies.
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Affiliation(s)
- Ubaldo Emilio Ruiz-Hernández
- Laboratorio de Investigación Clínica y Ambiental, Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico.
| | - Leda Ivonne Pelcastre-Rodriguez
- Laboratorio de Investigación Clínica y Ambiental, Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico.
| | - Omar Alejandro Cabrero-Martínez
- Laboratorio de Investigación Clínica y Ambiental, Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico.
| | - Cecilia Hernández-Cortez
- Laboratorio de Bioquímica Microbiana, Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico.
| | - Graciela Castro-Escarpulli
- Laboratorio de Investigación Clínica y Ambiental, Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Ciudad de México, Mexico.
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Campylobacter portucalensis sp. nov., a new species of Campylobacter isolated from the preputial mucosa of bulls. PLoS One 2020; 15:e0227500. [PMID: 31923228 PMCID: PMC6953823 DOI: 10.1371/journal.pone.0227500] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Accepted: 12/19/2019] [Indexed: 01/31/2023] Open
Abstract
A new species of the Campylobacter genus is described, isolated from the preputial mucosa of bulls (Bos taurus). The five isolates obtained exhibit characteristics of Campylobacter, being Gram-negative non-motile straight rods, oxidase positive, catalase negative and microaerophilic. Phenotypic characteristics and nucleotide sequence analysis of 16S rRNA and hsp60 genes demonstrated that these isolates belong to a novel species within the genus Campylobacter. Based on hsp60 gene phylogenetic analysis, the most related species are C. ureolyticus, C. blaseri and C. corcagiensis. The whole genome sequence analysis of isolate FMV-PI01 revealed that the average nucleotide identity with other Campylobacter species was less than 75%, which is far below the cut-off for isolates of the same species. However, whole genome sequence analysis identified coding sequences highly homologous with other Campylobacter spp. These included several virulence factor coding genes related with host cell adhesion and invasion, transporters involved in resistance to antimicrobials, and a type IV secretion system (T4SS), containing virB2-virB11/virD4 genes, highly homologous to the C. fetus subsp. venerealis. The genomic G+C content of isolate FMV-PI01 was 28.3%, which is one of the lowest values reported for species of the genus Campylobacter. For this species the name Campylobacter portucalensis sp. nov. is proposed, with FMV-PI01 (= LMG 31504, = CCUG 73856) as the type strain.
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Scrascia M, D'Addabbo P, Roberto R, Porcelli F, Oliva M, Calia C, Dionisi AM, Pazzani C. Characterization of CRISPR-Cas Systems in Serratia marcescens Isolated from Rhynchophorus ferrugineus (Olivier, 1790) (Coleoptera: Curculionidae). Microorganisms 2019; 7:microorganisms7090368. [PMID: 31546915 PMCID: PMC6780938 DOI: 10.3390/microorganisms7090368] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 09/09/2019] [Accepted: 09/16/2019] [Indexed: 12/13/2022] Open
Abstract
The CRISPR-Cas adaptive immune system has been attracting increasing scientific interest for biological functions and biotechnological applications. Data on the Serratia marcescens system are scarce. Here, we report a comprehensive characterisation of CRISPR-Cas systems identified in S. marcescens strains isolated as secondary symbionts of Rhynchophorus ferrugineus, also known as Red Palm Weevil (RPW), one of the most invasive pests of major cultivated palms. Whole genome sequencing was performed on four strains (S1, S5, S8, and S13), which were isolated from the reproductive apparatus of RPWs. Subtypes I-F and I-E were harboured by S5 and S8, respectively. No CRISPR-Cas system was detected in S1 or S13. Two CRISPR arrays (4 and 51 spacers) were detected in S5 and three arrays (11, 31, and 30 spacers) were detected in S8. The CRISPR-Cas systems were located in the genomic region spanning from ybhR to phnP, as if this were the only region where CRISPR-Cas loci were acquired. This was confirmed by analyzing the S. marcescens complete genomes available in the NCBI database. This region defines a genomic hotspot for horizontally acquired genes and/or CRISPR-Cas systems. This study also supplies the first identification of subtype I-E in S. marcescens.
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Affiliation(s)
- Maria Scrascia
- Department of Biology, University of Bari Aldo Moro, 70124 Bari, Italy.
| | - Pietro D'Addabbo
- Department of Biology, University of Bari Aldo Moro, 70124 Bari, Italy.
| | - Roberta Roberto
- Department of Plants, Food, and Soil Sciences, University of Bari Aldo Moro, 70124 Bari, Italy.
| | - Francesco Porcelli
- Department of Plants, Food, and Soil Sciences, University of Bari Aldo Moro, 70124 Bari, Italy.
| | - Marta Oliva
- Department of Biology, University of Bari Aldo Moro, 70124 Bari, Italy.
| | - Carla Calia
- Department of Biology, University of Bari Aldo Moro, 70124 Bari, Italy.
| | - Anna Maria Dionisi
- Department of Infectious diseases, Istituto Superiore di Sanità, 00161 Rome, Italy.
| | - Carlo Pazzani
- Department of Biology, University of Bari Aldo Moro, 70124 Bari, Italy.
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26
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Wu YW, Yang SH, Hwangbo M, Chu KH. Analysis of Zobellella denitrificans ZD1 draft genome: Genes and gene clusters responsible for high polyhydroxybutyrate (PHB) production from glycerol under saline conditions and its CRISPR-Cas system. PLoS One 2019; 14:e0222143. [PMID: 31513626 PMCID: PMC6742469 DOI: 10.1371/journal.pone.0222143] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 08/22/2019] [Indexed: 01/25/2023] Open
Abstract
Polyhydroxybutyrate (PHB) is biodegradable and renewable and thus considered as a promising alternative to petroleum-based plastics. However, PHB production is costly due to expensive carbon sources for culturing PHB-accumulating microorganisms under sterile conditions. We discovered a hyper PHB-accumulating denitrifying bacterium, Zobellella denitrificans ZD1 (referred as strain ZD1 hereafter) capable of using non-sterile crude glycerol (a waste from biodiesel production) and nitrate to produce high PHB yield under saline conditions. Nevertheless, the underlying genetic mechanisms of PHB production in strain ZD1 have not been elucidated. In this study, we discovered a complete pathway of glycerol conversion to PHB, a novel PHB synthesis gene cluster, a salt-tolerant gene cluster, denitrifying genes, and an assimilatory nitrate reduction gene cluster in the ZD1 genome. Interestingly, the novel PHB synthesis gene cluster was found to be conserved among marine Gammaproteobacteria. Higher levels of PHB accumulation were linked to higher expression levels of the PHB synthesis gene cluster in ZD1 grown with glycerol and nitrate under saline conditions. Additionally, a clustered regularly interspaced short palindromic repeat (CRISPR)-Cas type-I-E antiviral system was found in the ZD1 genome along with a long spacer list, in which most of the spacers belong to either double-stranded DNA viruses or unknown phages. The results of the genome analysis revealed strain ZD1 used the novel PHB gene cluster to produce PHB from non-sterile crude glycerol under saline conditions.
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Affiliation(s)
- Yu-Wei Wu
- Graduate Institute of Biomedical Informatics, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
- Clinical Big Data Research Center, Taipei Medical University Hospital, Taipei, Taiwan
| | - Shih-Hung Yang
- Zachry Department of Civil and Environmental Engineering, Texas A&M University, College Station, TX, United States of America
| | - Myung Hwangbo
- Zachry Department of Civil and Environmental Engineering, Texas A&M University, College Station, TX, United States of America
| | - Kung-Hui Chu
- Zachry Department of Civil and Environmental Engineering, Texas A&M University, College Station, TX, United States of America
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27
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Adaptation processes that build CRISPR immunity: creative destruction, updated. Essays Biochem 2019; 63:227-235. [PMID: 31186288 DOI: 10.1042/ebc20180073] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 05/13/2019] [Accepted: 05/14/2019] [Indexed: 01/01/2023]
Abstract
Prokaryotes can defend themselves against invading mobile genetic elements (MGEs) by acquiring immune memory against them. The memory is a DNA database located at specific chromosomal sites called CRISPRs (clustered regularly interspaced short palindromic repeats) that store fragments of MGE DNA. These are utilised to target and destroy returning MGEs, preventing re-infection. The effectiveness of CRISPR-based immune defence depends on 'adaptation' reactions that capture and integrate MGE DNA fragments into CRISPRs. This provides the means for immunity to be delivered against MGEs in 'interference' reactions. Adaptation and interference are catalysed by Cas (CRISPR-associated) proteins, aided by enzymes well known for other roles in cells. We survey the molecular biology of CRISPR adaptation, highlighting entirely new developments that may help us to understand how MGE DNA is captured. We focus on processes in Escherichia coli, punctuated with reference to other prokaryotes that illustrate how common requirements for adaptation, DNA capture and integration, can be achieved in different ways. We also comment on how CRISPR adaptation enzymes, and their antecedents, can be utilised for biotechnology.
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