151
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Gussow AB, Park AE, Borges AL, Shmakov SA, Makarova KS, Wolf YI, Bondy-Denomy J, Koonin EV. Machine-learning approach expands the repertoire of anti-CRISPR protein families. Nat Commun 2020; 11:3784. [PMID: 32728052 PMCID: PMC7391736 DOI: 10.1038/s41467-020-17652-0] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 07/08/2020] [Indexed: 11/28/2022] Open
Abstract
The CRISPR-Cas are adaptive bacterial and archaeal immunity systems that have been harnessed for the development of powerful genome editing and engineering tools. In the incessant host-parasite arms race, viruses evolved multiple anti-defense mechanisms including diverse anti-CRISPR proteins (Acrs) that specifically inhibit CRISPR-Cas and therefore have enormous potential for application as modulators of genome editing tools. Most Acrs are small and highly variable proteins which makes their bioinformatic prediction a formidable task. We present a machine-learning approach for comprehensive Acr prediction. The model shows high predictive power when tested against an unseen test set and was employed to predict 2,500 candidate Acr families. Experimental validation of top candidates revealed two unknown Acrs (AcrIC9, IC10) and three other top candidates were coincidentally identified and found to possess anti-CRISPR activity. These results substantially expand the repertoire of predicted Acrs and provide a resource for experimental Acr discovery.
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Affiliation(s)
- Ayal B Gussow
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, 20894, USA
| | - Allyson E Park
- Department of Microbiology and Immunology, University of California San Francisco, San Francisco, CA, USA
| | - Adair L Borges
- Department of Microbiology and Immunology, University of California San Francisco, San Francisco, CA, USA
| | - Sergey A Shmakov
- 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
| | - Yuri I Wolf
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, 20894, USA
| | - Joseph Bondy-Denomy
- Department of Microbiology and Immunology, University of California San Francisco, San Francisco, CA, 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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152
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Bertelli C, Tilley KE, Brinkman FSL. Microbial genomic island discovery, visualization and analysis. Brief Bioinform 2020; 20:1685-1698. [PMID: 29868902 PMCID: PMC6917214 DOI: 10.1093/bib/bby042] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 04/30/2018] [Indexed: 12/27/2022] Open
Abstract
Horizontal gene transfer (also called lateral gene transfer) is a major mechanism for microbial genome evolution, enabling rapid adaptation and survival in specific niches. Genomic islands (GIs), commonly defined as clusters of bacterial or archaeal genes of probable horizontal origin, are of particular medical, environmental and/or industrial interest, as they disproportionately encode virulence factors and some antimicrobial resistance genes and may harbor entire metabolic pathways that confer a specific adaptation (solvent resistance, symbiosis properties, etc). As large-scale analyses of microbial genomes increases, such as for genomic epidemiology investigations of infectious disease outbreaks in public health, there is increased appreciation of the need to accurately predict and track GIs. Over the past decade, numerous computational tools have been developed to tackle the challenges inherent in accurate GI prediction. We review here the main types of GI prediction methods and discuss their advantages and limitations for a routine analysis of microbial genomes in this era of rapid whole-genome sequencing. An assessment is provided of 20 GI prediction software methods that use sequence-composition bias to identify the GIs, using a reference GI data set from 104 genomes obtained using an independent comparative genomics approach. Finally, we present guidelines to assist researchers in effectively identifying these key genomic regions.
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Affiliation(s)
- Claire Bertelli
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada
| | - Keith E Tilley
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada
| | - Fiona S L Brinkman
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada
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153
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Dineshkumar K, Aparna V, Wu L, Wan J, Abdelaziz MH, Su Z, Wang S, Xu H. Bacterial bug-out bags: outer membrane vesicles and their proteins and functions. J Microbiol 2020; 58:531-542. [DOI: 10.1007/s12275-020-0026-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 05/06/2020] [Accepted: 05/12/2020] [Indexed: 01/08/2023]
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154
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A Novel Inducible Prophage from Burkholderia Vietnamiensis G4 is Widely Distributed across the Species and Has Lytic Activity against Pathogenic Burkholderia. Viruses 2020; 12:v12060601. [PMID: 32486377 PMCID: PMC7354579 DOI: 10.3390/v12060601] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 05/27/2020] [Accepted: 05/29/2020] [Indexed: 12/30/2022] Open
Abstract
Burkholderia species have environmental, industrial and medical significance, and are important opportunistic pathogens in individuals with cystic fibrosis (CF). Using a combination of existing and newly determined genome sequences, this study investigated prophage carriage across the species B. vietnamiensis, and also isolated spontaneously inducible prophages from a reference strain, G4. Eighty-one B. vietnamiensis genomes were bioinformatically screened for prophages using PHASTER (Phage Search Tool Enhanced Release) and prophage regions were found to comprise up to 3.4% of total genetic material. Overall, 115 intact prophages were identified and there was evidence of polylysogeny in 32 strains. A novel, inducible Mu-like phage (vB_BvM-G4P1) was isolated from B. vietnamiensis G4 that had lytic activity against strains of five Burkholderia species prevalent in CF infections, including the Boston epidemic B. dolosa strain SLC6. The cognate prophage to vB_BvM-G4P1 was identified in the lysogen genome and was almost identical (>93.5% tblastx identity) to prophages found in 13 other B. vietnamiensis strains (17% of the strain collection). Phylogenomic analysis determined that the G4P1-like prophages were widely distributed across the population structure of B. vietnamiensis. This study highlights how genomic characterization of Burkholderia prophages can lead to the discovery of novel bacteriophages with potential therapeutic or biotechnological applications.
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155
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Pei Z, Sadiq FA, Han X, Zhao J, Zhang H, Ross RP, Lu W, Chen W. Identification, characterization, and phylogenetic analysis of eight new inducible prophages in Lactobacillus. Virus Res 2020; 286:198003. [PMID: 32450182 DOI: 10.1016/j.virusres.2020.198003] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 04/26/2020] [Accepted: 04/29/2020] [Indexed: 10/24/2022]
Abstract
Lysogenic bacterial strains abound in the Lactobacillus genus and contain dormant prophages inserted within their genomes. To evaluate the prophage-induction potential of the Lactobacillus strains of six species, 142 randomly selected strains from these species were induced with Mitomycin C. Eight newly-induced phages were identified and found to be diverse in morphology. Among the six species assessed, Lactobacillus plantarum and Lactobacillus rhamnosus strains were generally insensitive to induction. The genomic characterizations of eight phages were performed via whole genome sequencing and protein prediction. Meanwhile, genome comparison of the induced phages and predicted prophages demonstrated that the prediction software PHASTER can accurately locate major prophage regions in Lactobacillus. A phylogenetic tree of the Lactobacillus phage population was constructed to obtain further insights into the clustering of individuals, two major groups were found, one of which consisted mostly of L. plantarum virulent phages, the other was represented by Lactobacillus casei/paracasei temperate phages. Finally, it was confirmed via genomic collinear analysis, which seven of the eight Lactobacillus temperate phages were newly discovered, and two Lactobacillus brevis temperate phages belonged to a novel lineage.
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Affiliation(s)
- Zhangming Pei
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Faizan Ahmed Sadiq
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Xiao Han
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
| | - Jianxin Zhao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; International Joint Research Center for Probiotics & Gut Health, Jiangnan University, Wuxi, Jiangsu, China
| | - Hao Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; International Joint Research Center for Probiotics & Gut Health, Jiangnan University, Wuxi, Jiangsu, China
| | - R Paul Ross
- International Joint Research Center for Probiotics & Gut Health, Jiangnan University, Wuxi, Jiangsu, China; APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Wenwei Lu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; National Engineering Research Center for Functional Food, Jiangnan University, Wuxi 214122, China
| | - Wei Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; National Engineering Research Center for Functional Food, Jiangnan University, Wuxi 214122, China; International Joint Research Center for Probiotics & Gut Health, Jiangnan University, Wuxi, Jiangsu, China; Beijing Innovation Centre of Food Nutrition and Human Health, Beijing Technology and Business University (BTBU), Beijing 100048, China.
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156
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Pratama AA, van Elsas JD. Gene mobility in microbiomes of the mycosphere and mycorrhizosphere -role of plasmids and bacteriophages. FEMS Microbiol Ecol 2020; 95:5454738. [PMID: 30980672 DOI: 10.1093/femsec/fiz053] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 04/12/2019] [Indexed: 12/22/2022] Open
Abstract
Microbial activity in soil, including horizontal gene transfer (HGT), occurs in soil hot spots and at "hot moments". Given their capacities to explore soil for nutrients, soil fungi (associated or not with plant roots) can act as (1) selectors of myco(rrhizo)sphere-adapted organisms and (2) accelerators of HGT processes across the cell populations that are locally present. This minireview critically examines our current understanding of the drivers of gene mobility in the myco(rrhizo)sphere. We place a special focus on the role of two major groups of gene mobility agents, i.e. plasmids and bacteriophages. With respect to plasmids, there is mounting evidence that broad-host-range (IncP-1β and PromA group) plasmids are prominent drivers of gene mobility across mycosphere inhabitants. A role of IncP-1β plasmids in Fe uptake processes has been revealed. Moreover, a screening of typical mycosphere-inhabiting Paraburkholderia spp. revealed carriage of integrated plasmids, next to prophages, that presumably confer fitness enhancements. In particular, functions involved in biofilm formation and nutrient uptake were thus identified. The potential of the respective gene mobility agents to promote the movement of such genes is critically examined.
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Affiliation(s)
- Akbar Adjie Pratama
- Department of Microbial Ecology - Groningen Institute for Evolutionary Life Sciences, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Jan Dirk van Elsas
- Department of Microbial Ecology - Groningen Institute for Evolutionary Life Sciences, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
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157
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Rainey PB, Quistad SD. Toward a dynamical understanding of microbial communities. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190248. [PMID: 32200735 PMCID: PMC7133524 DOI: 10.1098/rstb.2019.0248] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/09/2020] [Indexed: 12/13/2022] Open
Abstract
The challenge of moving beyond descriptions of microbial community composition to the point where understanding underlying eco-evolutionary dynamics emerges is daunting. While it is tempting to simplify through use of model communities composed of a small number of types, there is a risk that such strategies fail to capture processes that might be specific and intrinsic to complexity of the community itself. Here, we describe approaches that embrace this complexity and show that, in combination with metagenomic strategies, dynamical insight is increasingly possible. Arising from these studies is mounting evidence of rapid eco-evolutionary change among lineages and a sense that processes, particularly those mediated by horizontal gene transfer, not only are integral to system function, but are central to long-term persistence. That such dynamic, systems-level insight is now possible, means that the study and manipulation of microbial communities can move to new levels of inquiry. This article is part of the theme issue 'Conceptual challenges in microbial community ecology'.
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Affiliation(s)
- Paul B. Rainey
- Department of Microbial Population Biology, Max Planck Institute for Evolutionary Biology, 24306 Plön, Germany
- Laboratoire de Génétique de l'Evolution, Chemistry, Biology and Innovation (CBI) UMR8231, ESPCI Paris, CNRS, PSL Research University, 75231 Paris, France
| | - Steven D. Quistad
- Laboratoire de Génétique de l'Evolution, Chemistry, Biology and Innovation (CBI) UMR8231, ESPCI Paris, CNRS, PSL Research University, 75231 Paris, France
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158
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Characterization and Genomic Analysis of ValSw3-3, a New Siphoviridae Bacteriophage Infecting Vibrio alginolyticus. J Virol 2020; 94:JVI.00066-20. [PMID: 32132234 PMCID: PMC7199398 DOI: 10.1128/jvi.00066-20] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 02/25/2020] [Indexed: 02/08/2023] Open
Abstract
A novel lytic bacteriophage, ValSw3-3, which efficiently infects pathogenic strains of Vibrio alginolyticus, was isolated from sewage water and characterized by microbiological and in silico genomic analyses. Transmission electron microscopy indicated that ValSw3-3 has the morphology of siphoviruses. This phage can infect four species in the Vibrio genus and has a latent period of 15 min and a burst size of 95 ± 2 PFU/infected bacterium. Genome sequencing results show that ValSw3-3 has a 39,846-bp double-stranded DNA genome with a GC content of 43.1%. The similarity between the genome sequences of ValSw3-3 and those of other phages recorded in the GenBank database was below 50% (42%), suggesting that ValSw3-3 significantly differs from previously reported phages at the DNA level. Multiple genome comparisons and phylogenetic analysis based on the major capsid protein revealed that phage ValSw3-3 is grouped in a clade with five other phages, including Listonella phage phiHSIC (GenBank accession no. NC_006953.1), Vibrio phage P23 (MK097141.1), Vibrio phage pYD8-B (NC_021561.1), Vibrio phage 2E1 (KX507045.1), and Vibrio phage 12G5 (HQ632860.1), and is distinct from all known genera within the Siphoviridae family that have been ratified by the International Committee on Taxonomy of Viruses (ICTV). An in silico proteomic comparison of diverse phages from the Siphoviridae family supported this clustering result and suggested that ValSw3-3, phiHSIC, P23, pYD8-B, 2E1, and 12G5 should be classified as a novel genus cluster of Siphoviridae A subsequent analysis of core genes also revealed the common genes shared within this new cluster. Overall, these results provide a characterization of Vibrio phage ValSw3-3 and support our proposal of a new viral genus within the family Siphoviridae IMPORTANCE Phage therapy has been considered a potential alternative to antibiotic therapy in treating bacterial infections. For controlling the vibriosis-causing pathogen Vibrio alginolyticus, well-documented phage candidates are still lacking. Here, we characterize a novel lytic Vibrio phage, ValSw3-3, based on its morphology, host range and infectivity, growth characteristics, stability under various conditions, and genomic features. Our results show that ValSw3-3 could be a potent candidate for phage therapy to treat V. alginolyticus infections due to its stronger infectivity and better pH and thermal stability than those of previously reported Vibrio phages. Moreover, genome sequence alignments, phylogenetic analysis, in silico proteomic comparison, and core gene analysis all support that this novel phage, ValSw3-3, and five unclassified phages form a clade distant from those of other known genera ratified by the ICTV. Thus, we propose a new viral genus within the Siphoviridae family to accommodate this clade, with ValSw3-3 as a representative member.
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159
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Luo E, Eppley JM, Romano AE, Mende DR, DeLong EF. Double-stranded DNA virioplankton dynamics and reproductive strategies in the oligotrophic open ocean water column. THE ISME JOURNAL 2020; 14:1304-1315. [PMID: 32060418 PMCID: PMC7174320 DOI: 10.1038/s41396-020-0604-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 12/17/2019] [Accepted: 01/30/2020] [Indexed: 12/11/2022]
Abstract
Microbial communities are critical to ecosystem dynamics and biogeochemical cycling in the open oceans. Viruses are essential elements of these communities, influencing the productivity, diversity, and evolution of cellular hosts. To further explore the natural history and ecology of open-ocean viruses, we surveyed the spatiotemporal dynamics of double-stranded DNA (dsDNA) viruses in both virioplankton and bacterioplankton size fractions in the North Pacific Subtropical Gyre, one of the largest biomes on the planet. Assembly and clustering of viral genomes revealed a peak in virioplankton diversity at the base of the euphotic zone, where virus populations and host species richness both reached their maxima. Simultaneous characterization of both extracellular and intracellular viruses suggested depth-specific reproductive strategies. In particular, analyses indicated elevated lytic interactions in the mixed layer, more temporally variable temperate phage interactions at the base of the euphotic zone, and increased lysogeny in the mesopelagic ocean. Furthermore, the depth variability of auxiliary metabolic genes suggested habitat-specific strategies for viral influence on light-energy, nitrogen, and phosphorus acquisition during host infection. Most virus populations were temporally persistent over several years in this environment at the 95% nucleic acid identity level. In total, our analyses revealed variable distributional patterns and diverse reproductive and metabolic strategies of virus populations in the open-ocean water column.
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Affiliation(s)
- Elaine Luo
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education (C-MORE), University of Hawaii, Honolulu, HI, 96822, USA
| | - John M Eppley
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education (C-MORE), University of Hawaii, Honolulu, HI, 96822, USA
| | - Anna E Romano
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education (C-MORE), University of Hawaii, Honolulu, HI, 96822, USA
| | - Daniel R Mende
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education (C-MORE), University of Hawaii, Honolulu, HI, 96822, USA
| | - Edward F DeLong
- Daniel K. Inouye Center for Microbial Oceanography: Research and Education (C-MORE), University of Hawaii, Honolulu, HI, 96822, USA.
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160
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Zhou J, Sun T, Kang W, Tang D, Feng Q. Pathogenic and antimicrobial resistance genes in Streptococcus oralis strains revealed by comparative genome analysis. Genomics 2020; 112:3783-3793. [PMID: 32334114 DOI: 10.1016/j.ygeno.2020.04.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Revised: 04/03/2020] [Accepted: 04/20/2020] [Indexed: 02/05/2023]
Abstract
Streptococcus oralis is an early colonizer bacterium in dental plaques and is considered a potential pathogen of infective endocarditis (IE) disease. In this study, we built a complete genome map of Streptococcus oralis strain SOT, Streptococcus oralis strain SOD and Streptococcus infantis strain SO and performed comparative genomic analysis among these three strains. The results showed that there are five genomic islands (GIs) in strain SOT and one CRISPR in strain SOD. Each genome harbors various pathogenic genes related to diseases and drug resistance, while the antibiotic resistance genes in strains SOT and SOD were quite similar but different from those in strain SO. In addition, we identified 17 main virulence factors and capsule-related genes in three strains. These results suggest the pathogenic potential of Streptococcus strains, which lay a foundation for the prevention and treatment of a Streptococcus oralis infection.
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Affiliation(s)
- Jiannan Zhou
- Department of Human Microbiome, School and Hospital of Stomatology, Shandong University, Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, No. 44-1 Wenhua Road West, 250012 Jinan, Shandong, China
| | - Tianyong Sun
- Department of Human Microbiome, School and Hospital of Stomatology, Shandong University, Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, No. 44-1 Wenhua Road West, 250012 Jinan, Shandong, China
| | - Wenyan Kang
- Department of Human Microbiome, School and Hospital of Stomatology, Shandong University, Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, No. 44-1 Wenhua Road West, 250012 Jinan, Shandong, China
| | - Di Tang
- Department of Human Microbiome, School and Hospital of Stomatology, Shandong University, Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, No. 44-1 Wenhua Road West, 250012 Jinan, Shandong, China
| | - Qiang Feng
- Department of Human Microbiome, School and Hospital of Stomatology, Shandong University, Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, No. 44-1 Wenhua Road West, 250012 Jinan, Shandong, China; State Key Laboratory of Microbial Technology, Shandong University,266237 Qingdao, Shandong, China; NHC Key Laboratory of Otorhinolaryngology (Shandong University), Jinan, Shandong, China.
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161
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Arndt D, Marcu A, Liang Y, Wishart DS. PHAST, PHASTER and PHASTEST: Tools for finding prophage in bacterial genomes. Brief Bioinform 2020; 20:1560-1567. [PMID: 29028989 DOI: 10.1093/bib/bbx121] [Citation(s) in RCA: 118] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 07/31/2017] [Indexed: 11/13/2022] Open
Abstract
PHAST (PHAge Search Tool) and its successor PHASTER (PHAge Search Tool - Enhanced Release) have become two of the most widely used web servers for identifying putative prophages in bacterial genomes. Here we review the main capabilities of these web resources, provide some practical guidance regarding their use and discuss possible future improvements. PHAST, which was first described in 2011, made its debut just as whole bacterial genome sequencing and was becoming inexpensive and relatively routine. PHAST quickly gained popularity among bacterial genome researchers because of its web accessibility, its ease of use along with its enhanced accuracy and rapid processing times. PHASTER, which appeared in 2016, provided a number of much-needed enhancements to the PHAST server, including greater processing speed (to cope with very large submission volumes), increased database sizes, a more modern user interface, improved graphical displays and support for metagenomic submissions. Continuing developments in the field, along with increased interest in automated phage and prophage finding, have already led to several improvements to the PHASTER server and will soon lead to the development of a successor to PHASTER (to be called PHASTEST).
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162
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Mahendra C, Christie KA, Osuna BA, Pinilla-Redondo R, Kleinstiver BP, Bondy-Denomy J. Broad-spectrum anti-CRISPR proteins facilitate horizontal gene transfer. Nat Microbiol 2020; 5:620-629. [PMID: 32218510 PMCID: PMC7194981 DOI: 10.1038/s41564-020-0692-2] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 02/14/2020] [Indexed: 12/26/2022]
Abstract
CRISPR-Cas adaptive immune systems protect bacteria and archaea against their invading genetic parasites, including bacteriophages/viruses and plasmids. In response to this immunity, many phages have anti-CRISPR (Acr) proteins that inhibit CRISPR-Cas targeting. To date, anti-CRISPR genes have primarily been discovered in phage or prophage genomes. Here, we uncovered acr loci on plasmids and other conjugative elements present in Firmicutes using the Listeria acrIIA1 gene as a marker. The four identified genes, found in Listeria, Enterococcus, Streptococcus and Staphylococcus genomes, can inhibit type II-A SpyCas9 or SauCas9, and are thus named acrIIA16-19. In Enterococcus faecalis, conjugation of a Cas9-targeted plasmid was enhanced by anti-CRISPRs derived from Enterococcus conjugative elements, highlighting a role for Acrs in the dissemination of plasmids. Reciprocal co-immunoprecipitation showed that each Acr protein interacts with Cas9, and Cas9-Acr complexes were unable to cleave DNA. Northern blotting suggests that these anti-CRISPRs manipulate single guide RNA length, loading or stability. Mirroring their activity in bacteria, AcrIIA16 and AcrIIA17 provide robust and highly potent broad-spectrum inhibition of distinct Cas9 proteins in human cells (for example, SpyCas9, SauCas9, SthCas9, NmeCas9 and CjeCas9). This work presents a focused analysis of non-phage Acr proteins, demonstrating a role in horizontal gene transfer bolstered by broad-spectrum CRISPR-Cas9 inhibition.
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Affiliation(s)
- Caroline Mahendra
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA, USA
| | - Kathleen A Christie
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
- Department of Pathology, Massachusetts General Hospital, Boston, MA, USA
- Department of Pathology, Harvard Medical School, Boston, MA, USA
| | - Beatriz A Osuna
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA, USA
| | - Rafael Pinilla-Redondo
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA, USA
- Section of Microbiology, University of Copenhagen, Universitetsparken 15, Copenhagen, Denmark
- Department of Technological Educations, University College Copenhagen, Sigurdsgade 26, Copenhagen, Denmark
| | - Benjamin P Kleinstiver
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
- Department of Pathology, Massachusetts General Hospital, Boston, MA, USA
- Department of Pathology, Harvard Medical School, Boston, MA, USA
| | - Joseph Bondy-Denomy
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA, USA.
- Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA, USA.
- Innovative Genomics Institute, Berkeley, CA, USA.
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163
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Saroj DB, Gupta AK. Genome based safety assessment for Bacillus coagulans strain LBSC (DSM 17654) for probiotic application. Int J Food Microbiol 2020; 318:108523. [DOI: 10.1016/j.ijfoodmicro.2020.108523] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 10/30/2019] [Accepted: 01/12/2020] [Indexed: 01/12/2023]
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164
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Prolič-Kalinšek M, De Bruyn P, Jurėnas D, Van Melderen L, Loris R, Volkov AN. 1H, 13C, and 15N backbone and side chain chemical shift assignment of YdaS, a monomeric member of the HigA family. BIOMOLECULAR NMR ASSIGNMENTS 2020; 14:25-30. [PMID: 31625047 DOI: 10.1007/s12104-019-09915-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 10/03/2019] [Indexed: 06/10/2023]
Abstract
The cryptic prophage CP-933P in Escherichia coli O157:H7 contains a parDE-like toxin-antitoxin module, the operator region of which is recognized by two flanking transcription regulators: PaaR2 (ParE associated Regulator), which forms part of the paaR2-paaA2-parE2 toxin-antitoxin operon and YdaS (COG4197), which is encoded in the opposite direction but shares the operator. Here we report the 1H, 15N and 13C backbone and side chain chemical shift assignments of YdaS from Escherichia coli O157:H7 in its free state. YdaS is a distinct relative to HigA antitoxins but behaves as a monomer in solution. The BMRB Accession Number is 27917.
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Affiliation(s)
- Maruša Prolič-Kalinšek
- Structural Biology Brussels, Department of Biotechnology (DBIT), Vrije Universiteit Brussel, Brussels, Belgium
- VIB-VUB Center for Structural Biology, Brussels, Belgium
| | - Pieter De Bruyn
- Structural Biology Brussels, Department of Biotechnology (DBIT), Vrije Universiteit Brussel, Brussels, Belgium
- VIB-VUB Center for Structural Biology, Brussels, Belgium
| | - Dukas Jurėnas
- Cellular and Molecular Microbiology, Department of Molecular Biology, Université Libre de Bruxelles, Gosselies, Belgium
| | - Laurence Van Melderen
- Cellular and Molecular Microbiology, Department of Molecular Biology, Université Libre de Bruxelles, Gosselies, Belgium
| | - Remy Loris
- Structural Biology Brussels, Department of Biotechnology (DBIT), Vrije Universiteit Brussel, Brussels, Belgium.
- VIB-VUB Center for Structural Biology, Brussels, Belgium.
| | - Alexander N Volkov
- Structural Biology Brussels, Department of Biotechnology (DBIT), Vrije Universiteit Brussel, Brussels, Belgium
- VIB-VUB Center for Structural Biology, Brussels, Belgium
- Jean Jeener NMR Centre, Vrije Universiteit Brussel, Brussels, Belgium
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165
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Quistad SD, Doulcier G, Rainey PB. Experimental manipulation of selfish genetic elements links genes to microbial community function. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190681. [PMID: 32200751 PMCID: PMC7133536 DOI: 10.1098/rstb.2019.0681] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Microbial communities underpin the Earth's biological and geochemical processes, but their complexity hampers understanding. Motivated by the challenge of diversity and the need to forge ways of capturing dynamical behaviour connecting genes to function, biologically independent experimental communities comprising hundreds of microbial genera were established from garden compost and propagated on nitrogen-limited minimal medium with cellulose (paper) as sole carbon source. After 1 year of bi-weekly transfer, communities retained hundreds of genera. To connect genes to function, we used a simple experimental manipulation that involved the periodic collection of selfish genetic elements (SGEs) from separate communities, followed by pooling and redistribution across communities. The treatment was predicted to promote amplification and dissemination of SGEs and thus horizontal gene transfer. Confirmation came from comparative metagenomics, which showed the substantive movement of ecologically significant genes whose dynamic across space and time could be followed. Enrichment of genes implicated in nitrogen metabolism, and particularly ammonification, prompted biochemical assays that revealed a measurable impact on community function. Our simple experimental strategy offers a conceptually new approach for unravelling dynamical processes affecting microbial community function. This article is part of the theme issue ‘Conceptual challenges in microbial community ecology’.
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Affiliation(s)
- Steven D Quistad
- Laboratoire de Génétique de l'Evolution, Chemistry, Biology and Innovation (CBI) UMR8231, ESPCI Paris, CNRS, PSL Research University, 10 rue Vauquelin, Paris, France
| | - Guilhem Doulcier
- Laboratoire de Génétique de l'Evolution, Chemistry, Biology and Innovation (CBI) UMR8231, ESPCI Paris, CNRS, PSL Research University, 10 rue Vauquelin, Paris, France
| | - Paul B Rainey
- Laboratoire de Génétique de l'Evolution, Chemistry, Biology and Innovation (CBI) UMR8231, ESPCI Paris, CNRS, PSL Research University, 10 rue Vauquelin, Paris, France.,Department of Microbial Population Biology, Max Planck Institute for Evolutionary Biology, Plön 24306, Germany
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166
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Wei B, Peng Z, Huang T, Guan Q, Xie M, Xiong T. Stability of potential prophages in commercial strain Lactobacillus plantarum NCU116 under various stressors. Arch Microbiol 2020; 202:1241-1250. [PMID: 32112122 DOI: 10.1007/s00203-020-01813-2] [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: 07/04/2019] [Revised: 01/10/2020] [Accepted: 01/18/2020] [Indexed: 01/21/2023]
Abstract
Genetic stability of bacterium as a starter culture is vital for product quality in fermentation industry. The commercial strain Lactobacillus plantarum NCU116 widely used in fruit and vegetable fermentation was induced with various stressors to investigate the stability of potential prophages. PHAge Search Tool (PHAST) identified three potential prophages in bacterial genome. By spectrophotometric analysis, mitomycin C (MMC), lactic acid, and bile salt were found to inhibit the growth of L. plantarum NCU116 while ethanol and hydrogen peroxide had no notable impacts. Transcriptions of four phage-synthesizing genes (phaR, phacap, phaada, phatail) and four phage-resistant genes (cas116, helR, hsd1, hsd2) under stressors were investigated by quantitative reverse transcription PCR. MMC was found to most significantly upregulated transcriptions of phage-synthesizing genes, followed by lactic acid and bile salt. By transmission electron microscopy, no virus particles from the lysates of strain NCU116 treated by MMC were observed, corresponding to the result that no phage nucleic acids could be extracted from the supernatants of strain NCU116 treated by MMC. This study suggested that no prophages could be induced from L. plantarum NCU116 by strong inducer MMC, indicating its genetic stability, which supports the comprehensive application of strain NCU116 in industry without causing fermentation failure.
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Affiliation(s)
- Benliang Wei
- School of Food Science and Technology, Nanchang University, Nanchang, China
| | - Zhen Peng
- School of Food Science and Technology, Nanchang University, Nanchang, China.,State Key Laboratory of Food Science and Technology, Nanchang University, 235 East Nanjing Road, Nanchang, 330047, China
| | - Tao Huang
- School of Food Science and Technology, Nanchang University, Nanchang, China
| | - Qianqian Guan
- State Key Laboratory of Food Science and Technology, Nanchang University, 235 East Nanjing Road, Nanchang, 330047, China
| | - Mingyong Xie
- School of Food Science and Technology, Nanchang University, Nanchang, China.,State Key Laboratory of Food Science and Technology, Nanchang University, 235 East Nanjing Road, Nanchang, 330047, China
| | - Tao Xiong
- School of Food Science and Technology, Nanchang University, Nanchang, China. .,State Key Laboratory of Food Science and Technology, Nanchang University, 235 East Nanjing Road, Nanchang, 330047, China.
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167
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Pan M, Hidalgo-Cantabrana C, Barrangou R. Host and body site-specific adaptation of Lactobacillus crispatus genomes. NAR Genom Bioinform 2020; 2:lqaa001. [PMID: 33575551 PMCID: PMC7671364 DOI: 10.1093/nargab/lqaa001] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 12/09/2019] [Accepted: 01/06/2020] [Indexed: 12/13/2022] Open
Abstract
Lactobacillus crispatus is a common inhabitant of both healthy poultry gut and human vaginal tract, and the absence of this species has been associated with a higher risk of developing infectious diseases. In this study, we analyzed 105 L. crispatus genomes isolated from a variety of ecological niches, including the human vaginal tract, human gut, chicken gut and turkey gut, to shed light on the genetic and functional features that drive evolution and adaptation of this important species. We performed in silico analyses to identify the pan and core genomes of L. crispatus, and to reveal the genomic differences and similarities associated with their origins of isolation. Our results demonstrated that, although a significant portion of the genomic content is conserved, human and poultry L. crispatus isolates evolved to encompass different genomic features (e.g. carbohydrate usage, CRISPR-Cas immune systems, prophage occurrence) in order to thrive in different environmental niches. We also observed that chicken and turkey L. crispatus isolates can be differentiated based on their genomic information, suggesting significant differences may exist between these two poultry gut niches. These results provide insights into host and niche-specific adaptation patterns in species of human and animal importance.
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Affiliation(s)
- Meichen Pan
- Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, Raleigh, NC 27606, USA
| | - Claudio Hidalgo-Cantabrana
- Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, Raleigh, NC 27606, USA
| | - Rodolphe Barrangou
- Department of Food, Bioprocessing and Nutrition Sciences, North Carolina State University, Raleigh, NC 27606, USA
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168
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Abstract
With the increasing frequency of antibiotic resistance, it is critical to explore new therapeutic strategies for treating bacterial infections. Here, we use a temperate phage, i.e., one that integrates itself into the bacterial genome, to neutralize the expression of a virulence factor by modifying bacterial function at the genetic level. We show that Shiga toxin production can be significantly reduced in vitro and in the mammalian gut. Alternative to traditional applications of phage therapy that rely on killing bacteria, our genetics-based antivirulence approach introduces a new framework for treating bacterial infections. Elimination or alteration of select members of the gut microbiota is key to therapeutic efficacy. However, the complexity of these microbial inhabitants makes it challenging to precisely target bacteria. Here, we deliver exogenous genes to specific bacteria by genomic integration of temperate phage for long-lasting modification. As a real-world therapeutic test, we engineered λ phage to transcriptionally repress Shiga toxin by using genetic hybrids between λ and other lambdoid phages to overcome resistance encoded by the virulence-expressing prophage. We show that a single dose of engineered phage propagates throughout the bacterial community and reduces Shiga toxin production in an enteric mouse model of infection without markedly affecting bacterial concentrations. Our work reveals a new framework for transferring functions to bacteria within their native environment. IMPORTANCE With the increasing frequency of antibiotic resistance, it is critical to explore new therapeutic strategies for treating bacterial infections. Here, we use a temperate phage, i.e., one that integrates itself into the bacterial genome, to neutralize the expression of a virulence factor by modifying bacterial function at the genetic level. We show that Shiga toxin production can be significantly reduced in vitro and in the mammalian gut. Alternative to traditional applications of phage therapy that rely on killing bacteria, our genetics-based antivirulence approach introduces a new framework for treating bacterial infections.
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169
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Cubo MT, Alías-Villegas C, Balsanelli E, Mesa D, de Souza E, Espuny MR. Diversity of Sinorhizobium (Ensifer) meliloti Bacteriophages in the Rhizosphere of Medicago marina: Myoviruses, Filamentous and N4-Like Podovirus. Front Microbiol 2020; 11:22. [PMID: 32038600 PMCID: PMC6992544 DOI: 10.3389/fmicb.2020.00022] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 01/07/2020] [Indexed: 02/02/2023] Open
Abstract
Using different Sinorhizobium meliloti strains as hosts, we isolated eight new virulent phages from the rhizosphere of the coastal legume Medicago marina. Half of the isolated phages showed a very narrow host range while the other half exhibited a wider host range within the strains tested. Electron microscopy studies showed that phages M_ort18, M_sf1.2, and M_sf3.33 belonged to the Myoviridae family with feature long, contractile tails and icosaedral head. Phages I_sf3.21 and I_sf3.10T appeared to have filamentous shape and produced turbid plaques, which is a characteristic of phages from the Inoviridae family. Phage P_ort11 is a member of the Podoviridae, with an icosahedral head and a short tail and was selected for further characterization and genome sequencing. P_ort11 contained linear, double-stranded DNA with a length of 75239 bp and 103 putative open reading frames. BLASTP analysis revealed strong similarities to Escherichia phage N4 and other N4-like phages. This is the first report of filamentous and N4-like phages that infect S. meliloti.
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Affiliation(s)
- María Teresa Cubo
- Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Seville, Spain
| | - Cynthia Alías-Villegas
- Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Seville, Spain
| | - Eduardo Balsanelli
- Department of Biochemistry and Molecular Biology, Universidade Federal do Paraná, Curitiba, Brazil
| | - Dany Mesa
- Department of Biochemistry and Molecular Biology, Universidade Federal do Paraná, Curitiba, Brazil
| | - Emanuel de Souza
- Department of Biochemistry and Molecular Biology, Universidade Federal do Paraná, Curitiba, Brazil
| | - María Rosario Espuny
- Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Seville, Spain
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170
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Si-Tuan N, Ngoc HM, Nhat LD, Nguyen C, Pham HQ, Huong NT. Genomic features, whole-genome phylogenetic and comparative genomic analysis of extreme-drug-resistant ventilator-associated-pneumonia Acinetobacter baumannii strain in a Vietnam hospital. INFECTION GENETICS AND EVOLUTION 2020; 80:104178. [PMID: 31917358 DOI: 10.1016/j.meegid.2020.104178] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 12/31/2019] [Accepted: 01/05/2020] [Indexed: 01/14/2023]
Abstract
OBJECTIVES Acinetobacter baumannii is a major cause of ventilator-associated-pneumonia (VAP) worldwide due to its impressive propensity to rapidly acquire resistance elements to a wide range of antibacterial agents. We sought to explore the genomic features of this pathogen from a sputum specimen of a VAP male patient. METHODS Whole genome analysis of A. baumannii DMS06670 included de novo assembly; functional annotation, whole-genome-phylogenetic analysis, antibiotics genes identification, prophage regions, virulent factor and pan-genome analysis. RESULTS Assembly of whole-genome shotgun sequences of strain DMS06670 yielded an estimated genome size of 3.8 Mb with Sequence Type 447. Functional annotation and orthologous protein cluster analysis identified several potential antibiotic resistance genes was conducted (with 1 novel gene), prophage regions, virulent factors. The clusters of orthologous groups (COGs) analysis in protein sequence of the A. baumannii strain was compared with the other five genomes showed that the orthologous protein clusters responsible for multi-drug exist inside highly antimicrobial resistant strains. Whole-genome phylogenetic and in silico MLST analysis revealed that this A. baumannii strain is in the same clade as strains LAC-4 and BJAB0715. Comparative analysis of 23 available genomes of A. baumannii revealed a pan-genome consisting of 15,883 genes. CONCLUSION Our findings provide insight into the virulence-associated genes and then compared with the genomes of other A. baumannii strains by calculation of ANI values and pan-genome analysis. Functional studies of these pathogens are required to validate these findings.
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Affiliation(s)
- Nguyen Si-Tuan
- Department of Biotechnology, Faculty of Chemical Engineering, Ho Chi Minh City University of Technology, HCM National University, Vietnam; Department of Medical Microbiology, Thongnhat General Hospital of Dongnai Province, Vietnam.
| | - Hua My Ngoc
- Department of Medical Biochemistry, Thongnhat General Hospital of Dongnai Province, Vietnam
| | - Le Duy Nhat
- Department of Medical Microbiology, Thongnhat General Hospital of Dongnai Province, Vietnam
| | | | - Huy Quang Pham
- School of Applied Biosciences, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 702-701, Republic of Korea
| | - Nguyen Thuy Huong
- Department of Biotechnology, Faculty of Chemical Engineering, Ho Chi Minh City University of Technology, HCM National University, Vietnam
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171
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Abstract
Here we introduce methods for the detection, enumeration, and isolation of bacteriophages from Escherichia coli. In bacteria, horizontal gene transfer may be mediated by virulent and temperate phages. Strict virulent phages, able to propagate in a suitable strain following the lytic pathway, can be isolated directly from different natural environments. In temperate phages, the lytic cycle must be activated, and phages are detected after their induction. In both cases, detection is based on the production of visible plaques in a confluent lawn of the host strain using a double agar layer method. Further purification and characterization are achieved by density gradients, electron microscopy studies, and genomic analysis. This straightforward methodology can be applied to the detection, enumeration, and isolation of bacteriophages from any bacterial species, using the appropriate host strain, media, and culture conditions.
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Affiliation(s)
- Juan Jofre
- Department of Microbiology, University of Barcelona, Barcelona, Spain
| | - Maite Muniesa
- Department of Microbiology, University of Barcelona, Barcelona, Spain.
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172
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Jarocki P, Komoń-Janczara E, Podleśny M, Kholiavskyi O, Pytka M, Kordowska-Wiater M. Genomic and Proteomic Characterization of Bacteriophage BH1 Spontaneously Released from Probiotic Lactobacillus rhamnosus Pen. Viruses 2019; 11:E1163. [PMID: 31888239 PMCID: PMC6950654 DOI: 10.3390/v11121163] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 12/10/2019] [Accepted: 12/13/2019] [Indexed: 02/06/2023] Open
Abstract
Lactobacillus rhamnosus Pen is a human endogenous strain used for the production of probiotic formula, which is effective in the prevention of antibiotic-associated diarrhoea. Our study showed that this probiotic strain releases bacteriophage BH1 without the addition of any inducing agent. Our research revealed that phage BH1 has a circular genome with a length of 40721 nt and a GC content of 44.8%. The genome of phage BH1 possesses 57 open reading frames which could be divided into functional modules associated with DNA packaging, morphogenesis, lysis, integration, genetic switch, and replication. In spite of similarity in morphology and genomic organization, comparative analysis revealed substantial genetic diversity and mosaic genomic architecture among phages described for the Lactobacillus casei group. Additionally, qPCR and ddPCR analysis confirmed earlier microscopic observations indicating that L. rhamnosus Pen liberates bacteriophage particles during growth. This occurs spontaneously, and is not a result of external inducing factors. For samples collected after 4 and 24 h of L. rhamnosus Pen culture, the number of attB and attP copies increased 2.5 and 12 times, respectively. This phenomenon, by introducing resistance to other phages or enhancing the biofilm-forming capabilities, may increase the survivability of microorganisms in their natural ecological niche. Conversely, spontaneous phage induction may be an important virulence factor for bacteria, posing a potential threat for the human host.
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Affiliation(s)
- Piotr Jarocki
- Department of Biotechnology, Microbiology and Human Nutrition, University of Life Sciences in Lublin, 8 Skromna St., 20-704 Lublin, Poland
| | - Elwira Komoń-Janczara
- Department of Biotechnology, Microbiology and Human Nutrition, University of Life Sciences in Lublin, 8 Skromna St., 20-704 Lublin, Poland
| | - Marcin Podleśny
- Process and Development Department, Al. Tysiąclecia Państwa Polskiego 13, Grupa Azoty Zakłady Azotowe “Puławy” S.A, 24-110 Puławy, Poland
| | - Oleksandr Kholiavskyi
- Department of Biotechnology, Microbiology and Human Nutrition, University of Life Sciences in Lublin, 8 Skromna St., 20-704 Lublin, Poland
| | - Monika Pytka
- Department of Biotechnology, Microbiology and Human Nutrition, University of Life Sciences in Lublin, 8 Skromna St., 20-704 Lublin, Poland
| | - Monika Kordowska-Wiater
- Department of Biotechnology, Microbiology and Human Nutrition, University of Life Sciences in Lublin, 8 Skromna St., 20-704 Lublin, Poland
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173
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Phytovirome Analysis of Wild Plant Populations: Comparison of Double-Stranded RNA and Virion-Associated Nucleic Acid Metagenomic Approaches. J Virol 2019; 94:JVI.01462-19. [PMID: 31597769 DOI: 10.1128/jvi.01462-19] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 10/01/2019] [Indexed: 12/29/2022] Open
Abstract
Metagenomic studies have indicated that the diversity of plant viruses was until recently far underestimated. As important components of ecosystems, there is a need to explore the diversity and richness of the viruses associated with plant populations and to understand the drivers shaping their diversity in space and time. Two viral sequence enrichment approaches, double-stranded RNA (dsRNA) and virion-associated nucleic acids (VANA), have been used and compared here for the description of the virome of complex plant pools representative of the most prevalent plant species in unmanaged and cultivated ecosystems. A novel bioinformatics strategy was used to assess viral richness not only at the family level but also by determining operational taxonomic units (OTU) following the clustering of conserved viral domains. A large viral diversity dominated by novel dsRNA viruses was detected in all sites, while a large between-site variability limited the ability to draw a clear conclusion on the impact of cultivation. A trend for a higher diversity of dsRNA viruses was nevertheless detected in unmanaged sites (118 versus 77 unique OTUs). The dsRNA-based approach consistently revealed a broader and more comprehensive diversity for RNA viruses than the VANA approach, whatever the assessment criterion. In addition, dissimilarity analyses indicated both approaches to be largely reproducible but not necessarily convergent. These findings illustrate features of phytoviromes in various ecosystems and a novel strategy for precise virus richness estimation. These results allow us to reason methodological choices in phytovirome studies and likely in other virome studies where RNA viruses are the focal taxa.IMPORTANCE There are today significant knowledge gaps on phytovirus populations and on the drivers impacting them but also on the comparative performance-methodological approaches for their study. We used and compared two viral sequence enrichment approaches, double-stranded RNAs (dsRNA) and virion-associated nucleic acids (VANA), for phytovirome description in complex pools representative of the most prevalent plant species in unmanaged and cultivated ecosystems. Viral richness was assessed by determining operational taxonomic units (OTU) following the clustering of conserved viral domains. There is some limited evidence of an impact of cultivation on viral populations. These results provide data allowing us to reason the methodological choices in virome studies. For researchers primarily interested in RNA viruses, the dsRNA approach is recommended because it consistently provided a more comprehensive description of the analyzed phytoviromes, but it understandably underrepresented DNA viruses and bacteriophages.
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174
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Negri A, Jąkalski M, Szczuka A, Pryszcz LP, Mruk I. Transcriptome analyses of cells carrying the Type II Csp231I restriction-modification system reveal cross-talk between two unrelated transcription factors: C protein and the Rac prophage repressor. Nucleic Acids Res 2019; 47:9542-9556. [PMID: 31372643 PMCID: PMC6765115 DOI: 10.1093/nar/gkz665] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 07/16/2019] [Accepted: 07/23/2019] [Indexed: 12/27/2022] Open
Abstract
Restriction-modification (R–M) systems represent an effective mechanism of defence against invading bacteriophages, and are widely spread among bacteria and archaea. In acquiring a Type II R–M system via horizontal gene transfer, the new hosts become more resistant to phage infection, through the action of a restriction endonuclease (REase), which recognizes and cleaves specific target DNAs. To protect the host cell's DNA, there is also a methyltransferase (MTase), which prevents DNA cleavage by the cognate REase. In some R–M systems, the host also accepts a cis-acting transcription factor (C protein), which regulates the counteracting activities of REase and MTase to avoid host self-restriction. Our study characterized the unexpected phenotype of Escherichia coli cells, which manifested as extensive cell filamentation triggered by acquiring the Csp231I R–M system from Citrobacter sp. Surprisingly, we found that the cell morphology defect was solely dependent on the C regulator. Our transcriptome analysis supported by in vivo and in vitro assays showed that C protein directly silenced the expression of the RacR repressor to affect the Rac prophage-related genes. The rac locus ydaST genes, when derepressed, exerted a toxicity indicated by cell filamentation through an unknown mechanism. These results provide an apparent example of transcription factor cross-talk, which can have significant consequences for the host, and may represent a constraint on lateral gene transfer.
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Affiliation(s)
- Alessandro Negri
- Department of Microbiology, Faculty of Biology, University of Gdansk, Wita Stwosza 59, Gdansk 80-308, Poland
| | - Marcin Jąkalski
- Department of Plant Taxonomy and Nature Conservation, University of Gdansk, Wita Stwosza 59, 80-308 Gdansk, Poland
| | - Aleksandra Szczuka
- Department of Microbiology, Faculty of Biology, University of Gdansk, Wita Stwosza 59, Gdansk 80-308, Poland
| | - Leszek P Pryszcz
- Laboratory of Zebrafish Developmental Genomics, International Institute of Molecular and Cell Biology, Warsaw, ul. Trojdena 4, 02-109 Warsaw, Poland
| | - Iwona Mruk
- Department of Microbiology, Faculty of Biology, University of Gdansk, Wita Stwosza 59, Gdansk 80-308, Poland
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175
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Mohapatra B, Kazy SK, Sar P. Comparative genome analysis of arsenic reducing, hydrocarbon metabolizing groundwater bacterium Achromobacter sp. KAs 3-5T explains its competitive edge for survival in aquifer environment. Genomics 2019; 111:1604-1619. [DOI: 10.1016/j.ygeno.2018.11.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 10/25/2018] [Accepted: 11/05/2018] [Indexed: 11/24/2022]
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176
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Abstract
Colorectal cancer (CRC) is a common cancer globally. It is a complex disease influenced by genetic and environmental factors. Early studies on familial cases have identified major genes involved in CRC, such as proto-oncogenes KRAS, PIK3CA and BRAF, and tumour-suppressor genes APC and TP53. These genes have provided valuable insight into the molecular pathogenesis of CRC, and some have made ways to clinical utility to help diagnose cancer syndromes, prognosticate oncological outcomes and predict treatment responses. While these genetic factors are important, recent studies have suggested contribution of microorganisms to colorectal carcinogenesis. Observational studies, animal experiments and translational works have identified several microorganisms as potential carcinogenic bacteria, such as Fusobacterium nucleatum and Peptostreptococcus anaerobius. With the advent of sequencing technology and bioinformatics, more genomic and metagenomic factors are being uncovered as important players in CRC carcinogenesis. This article aims to review recent genomic and metagenomic discoveries relating to CRC.
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Affiliation(s)
- Charmaine Ng
- Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Haojun Li
- Li Ka Shing Institute of Health Science, State Key Laboratory of Digestive Disease, Institute of Digestive Disease, Department of Medicine and Therapeutics, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - William K K Wu
- Li Ka Shing Institute of Health Science, State Key Laboratory of Digestive Disease, Institute of Digestive Disease, Department of Medicine and Therapeutics, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.,Department of Anaesthesia and Intensive Care, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Sunny H Wong
- Department of Anaesthesia and Intensive Care, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Jun Yu
- Department of Anaesthesia and Intensive Care, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
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177
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Pfeifer E, Hünnefeld M, Popa O, Frunzke J. Impact of Xenogeneic Silencing on Phage-Host Interactions. J Mol Biol 2019; 431:4670-4683. [PMID: 30796986 PMCID: PMC6925973 DOI: 10.1016/j.jmb.2019.02.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 02/07/2019] [Accepted: 02/11/2019] [Indexed: 01/21/2023]
Abstract
Phages, viruses that prey on bacteria, are the most abundant and diverse inhabitants of the Earth. Temperate bacteriophages can integrate into the host genome and, as so-called prophages, maintain a long-term association with their host. The close relationship between host and virus has significantly shaped microbial evolution and phage elements may benefit their host by providing new functions. Nevertheless, the strong activity of phage promoters and potentially toxic gene products may impose a severe fitness burden and must be tightly controlled. In this context, xenogeneic silencing (XS) proteins, which can recognize foreign DNA elements, play an important role in the acquisition of novel genetic information and facilitate the evolution of regulatory networks. Currently known XS proteins fall into four classes (H-NS, MvaT, Rok and Lsr2) and have been shown to follow a similar mode of action by binding to AT-rich DNA and forming an oligomeric nucleoprotein complex that silences gene expression. In this review, we focus on the role of XS proteins in phage-host interactions by highlighting the important function of XS proteins in maintaining the lysogenic state and by providing examples of how phages fight back by encoding inhibitory proteins that disrupt XS functions in the host. Sequence analysis of available phage genomes revealed the presence of genes encoding Lsr2-type proteins in the genomes of phages infecting Actinobacteria. These data provide an interesting perspective for future studies to elucidate the impact of phage-encoded XS homologs on the phage life cycle and phage-host interactions.
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Affiliation(s)
- Eugen Pfeifer
- Forschungszentrum Jülich GmbH, Institute for Bio- and Geosciences 1, IBG1, 52425 Jülich, Germany.
| | - Max Hünnefeld
- Forschungszentrum Jülich GmbH, Institute for Bio- and Geosciences 1, IBG1, 52425 Jülich, Germany
| | - Ovidiu Popa
- Heinrich Heine Universität Düsseldorf, Institute for Quantitative and Theoretical Biology, 40223 Düsseldorf, Germany
| | - Julia Frunzke
- Forschungszentrum Jülich GmbH, Institute for Bio- and Geosciences 1, IBG1, 52425 Jülich, Germany.
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178
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Argov T, Sapir SR, Pasechnek A, Azulay G, Stadnyuk O, Rabinovich L, Sigal N, Borovok I, Herskovits AA. Coordination of cohabiting phage elements supports bacteria-phage cooperation. Nat Commun 2019; 10:5288. [PMID: 31754112 PMCID: PMC6872733 DOI: 10.1038/s41467-019-13296-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 10/30/2019] [Indexed: 01/08/2023] Open
Abstract
Bacterial pathogens often carry multiple prophages and other phage-derived elements within their genome, some of which can produce viral particles in response to stress. Listeria monocytogenes 10403S harbors two phage elements in its chromosome, both of which can trigger bacterial lysis under stress: an active prophage (ϕ10403S) that promotes the virulence of its host and can produce infective virions, and a locus encoding phage tail-like bacteriocins. Here, we show that the two phage elements are co-regulated, with the bacteriocin locus controlling the induction of the prophage and thus its activity as a virulence-associated molecular switch. More specifically, a metalloprotease encoded in the bacteriocin locus is upregulated in response to stress and acts as an anti-repressor for CI-like repressors encoded in each phage element. Our results provide molecular insight into the phenomenon of polylysogeny and its intricate adaptation to complex environments.
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Affiliation(s)
- Tal Argov
- The School of Molecular Cell Biology and Biotechnology, Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel
| | - Shai Ran Sapir
- The School of Molecular Cell Biology and Biotechnology, Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel
| | - Anna Pasechnek
- The School of Molecular Cell Biology and Biotechnology, Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel
| | - Gil Azulay
- The School of Molecular Cell Biology and Biotechnology, Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel
| | - Olga Stadnyuk
- The School of Molecular Cell Biology and Biotechnology, Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel
| | - Lev Rabinovich
- The School of Molecular Cell Biology and Biotechnology, Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel
| | - Nadejda Sigal
- The School of Molecular Cell Biology and Biotechnology, Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel
| | - Ilya Borovok
- The School of Molecular Cell Biology and Biotechnology, Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel
| | - Anat A Herskovits
- The School of Molecular Cell Biology and Biotechnology, Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv, 69978, Israel.
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179
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Khan A, Wahl LM. Quantifying the forces that maintain prophages in bacterial genomes. Theor Popul Biol 2019; 133:168-179. [PMID: 31758948 DOI: 10.1016/j.tpb.2019.11.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 11/08/2019] [Accepted: 11/12/2019] [Indexed: 10/25/2022]
Abstract
Genome sequencing has revealed that prophages, viral sequences integrated in a bacterial chromosome, are abundant, accounting for as much as 20% of the bacterial genome. These sequences can confer fitness benefits to the bacterial host, but may also instigate cell death through induction. Several recent investigations have revealed that the distribution of prophage lengths is bimodal, with a clear distinction between small and large prophages. Here we develop a mathematical model of the evolutionary forces affecting the prophage size distribution, and fit this model to three recent data sets. This approach offers quantitative estimates for the relative rates of lysogeny, induction, mutational degradation and selection acting on a wide class of prophage sequences. The model predicts that large prophages are predominantly maintained by the introduction of new prophage sequences through lysogeny, whereas shorter prophages can be enriched when they no longer encode the genes necessary for induction, but still offer selective benefits to their hosts.
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Affiliation(s)
- Amjad Khan
- Department of Applied Mathematics, Western University, London, ON, Canada
| | - Lindi M Wahl
- Department of Applied Mathematics, Western University, London, ON, Canada.
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180
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Cryptic-Prophage-Encoded Small Protein DicB Protects Escherichia coli from Phage Infection by Inhibiting Inner Membrane Receptor Proteins. J Bacteriol 2019; 201:JB.00475-19. [PMID: 31527115 PMCID: PMC6832061 DOI: 10.1128/jb.00475-19] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 09/12/2019] [Indexed: 02/06/2023] Open
Abstract
Temperate bacteriophages can integrate their genomes into the bacterial host chromosome and exist as prophages whose gene products play key roles in bacterial fitness and interactions with eukaryotic host organisms. Most bacterial chromosomes contain “cryptic” prophages that have lost genes required for production of phage progeny but retain genes of unknown function that may be important for regulating bacterial host physiology. This study provides such an example, where a cryptic-prophage-encoded product can perform multiple roles in the bacterial host and influence processes, including metabolism, cell division, and susceptibility to phage infection. Further functional characterization of cryptic-prophage-encoded functions will shed new light on host-phage interactions and their cellular physiological implications. Bacterial genomes harbor cryptic prophages that have lost genes required for induction, excision from host chromosomes, or production of phage progeny. Escherichia coli K-12 strains contain a cryptic prophage, Qin, that encodes a small RNA, DicF, and a small protein, DicB, that have been implicated in control of bacterial metabolism and cell division. Since DicB and DicF are encoded in the Qin immunity region, we tested whether these gene products could protect the E. coli host from bacteriophage infection. Transient expression of the dicBF operon yielded cells that were ∼100-fold more resistant to infection by λ phage than control cells, and the phenotype was DicB dependent. DicB specifically inhibited infection by λ and other phages that use ManYZ membrane proteins for cytoplasmic entry of phage DNA. In addition to blocking ManYZ-dependent phage infection, DicB also inhibited the canonical sugar transport activity of ManYZ. Previous studies demonstrated that DicB interacts with MinC, an FtsZ polymerization inhibitor, causing MinC localization to midcell and preventing Z ring formation and cell division. In strains producing mutant MinC proteins that do not interact with DicB, both DicB-dependent phenotypes involving ManYZ were lost. These results suggest that DicB is a pleiotropic regulator of bacterial physiology and cell division and that these effects are mediated by a key molecular interaction with the cell division protein MinC. IMPORTANCE Temperate bacteriophages can integrate their genomes into the bacterial host chromosome and exist as prophages whose gene products play key roles in bacterial fitness and interactions with eukaryotic host organisms. Most bacterial chromosomes contain “cryptic” prophages that have lost genes required for production of phage progeny but retain genes of unknown function that may be important for regulating bacterial host physiology. This study provides such an example, where a cryptic-prophage-encoded product can perform multiple roles in the bacterial host and influence processes, including metabolism, cell division, and susceptibility to phage infection. Further functional characterization of cryptic-prophage-encoded functions will shed new light on host-phage interactions and their cellular physiological implications.
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181
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DNA Packaging and Genomics of the Salmonella 9NA-Like Phages. J Virol 2019; 93:JVI.00848-19. [PMID: 31462565 DOI: 10.1128/jvi.00848-19] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 08/26/2019] [Indexed: 12/14/2022] Open
Abstract
We present the genome sequences of Salmonella enterica tailed phages Sasha, Sergei, and Solent. These phages, along with Salmonella phages 9NA, FSL_SP-062, and FSL_SP-069 and the more distantly related Proteus phage PmiS-Isfahan, have similarly sized genomes of between 52 and 57 kbp in length that are largely syntenic. Their genomes also show substantial genome mosaicism relative to one another, which is common within tailed phage clusters. Their gene content ranges from 80 to 99 predicted genes, of which 40 are common to all seven and form the core genome, which includes all identifiable virion assembly and DNA replication genes. The total number of gene types (pangenome) in the seven phages is 176, and 59 of these are unique to individual phages. Their core genomes are much more closely related to one another than to the genome of any other known phage, and they comprise a well-defined cluster within the family Siphoviridae To begin to characterize this group of phages in more experimental detail, we identified the genes that encode the major virion proteins and examined the DNA packaging of the prototypic member, phage 9NA. We show that it uses a pac site-directed headful packaging mechanism that results in virion chromosomes that are circularly permuted and about 13% terminally redundant. We also show that its packaging series initiates with double-stranded DNA cleavages that are scattered across a 170-bp region and that its headful measuring device has a precision of ±1.8%.IMPORTANCE The 9NA-like phages are clearly highly related to each other but are not closely related to any other known phage type. This work describes the genomes of three new 9NA-like phages and the results of experimental analysis of the proteome of the 9NA virion and DNA packaging into the 9NA phage head. There is increasing interest in the biology of phages because of their potential for use as antibacterial agents and for their ecological roles in bacterial communities. 9NA-like phages that infect two bacterial genera have been identified to date, and related phages infecting additional Gram-negative bacterial hosts are likely to be found in the future. This work provides a foundation for the study of these phages, which will facilitate their study and potential use.
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182
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Garmaeva S, Sinha T, Kurilshikov A, Fu J, Wijmenga C, Zhernakova A. Studying the gut virome in the metagenomic era: challenges and perspectives. BMC Biol 2019; 17:84. [PMID: 31660953 PMCID: PMC6819614 DOI: 10.1186/s12915-019-0704-y] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 09/22/2019] [Indexed: 12/12/2022] Open
Abstract
The human gut harbors a complex ecosystem of microorganisms, including bacteria and viruses. With the rise of next-generation sequencing technologies, we have seen a quantum leap in the study of human-gut-inhabiting bacteria, yet the viruses that infect these bacteria, known as bacteriophages, remain underexplored. In this review, we focus on what is known about the role of bacteriophages in human health and the technical challenges involved in studying the gut virome, of which they are a major component. Lastly, we discuss what can be learned from studies of bacteriophages in other ecosystems.
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Affiliation(s)
- Sanzhima Garmaeva
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Trishla Sinha
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Alexander Kurilshikov
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Jingyuan Fu
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.,Department of Pediatrics, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Cisca Wijmenga
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Alexandra Zhernakova
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
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183
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Rezaei Javan R, Ramos-Sevillano E, Akter A, Brown J, Brueggemann AB. Prophages and satellite prophages are widespread in Streptococcus and may play a role in pneumococcal pathogenesis. Nat Commun 2019; 10:4852. [PMID: 31649284 PMCID: PMC6813308 DOI: 10.1038/s41467-019-12825-y] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 09/27/2019] [Indexed: 02/06/2023] Open
Abstract
Prophages (viral genomes integrated within a host bacterial genome) can confer various phenotypic traits to their hosts, such as enhanced pathogenicity. Here we analyse >1300 genomes of 70 different Streptococcus species and identify nearly 800 prophages and satellite prophages (prophages that do not encode their own structural components but rely on the bacterial host and another helper prophage for survival). We show that prophages and satellite prophages are widely distributed among streptococci in a structured manner, and constitute two distinct entities with little effective genetic exchange between them. Cross-species transmission of prophages is not uncommon. Furthermore, a satellite prophage is associated with virulence in a mouse model of Streptococcus pneumoniae infection. Our findings highlight the potential importance of prophages in streptococcal biology and pathogenesis. Prophages are viral genomes integrated within bacterial genomes. Here, Rezaei Javan et al. identify nearly 800 prophages and satellite prophages in > 1300 Streptococcus genomes, and show that a satellite prophage is associated with virulence in a mouse model of pneumococcal infection.
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Affiliation(s)
| | | | - Asma Akter
- Department of Medicine, Imperial College London, London, UK
| | - Jeremy Brown
- UCL Respiratory, Division of Medicine, University College London, London, UK
| | - Angela B Brueggemann
- Nuffield Department of Medicine, University of Oxford, Oxford, UK. .,Department of Medicine, Imperial College London, London, UK. .,Nuffield Department of Population Health, University of Oxford, Oxford, UK.
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184
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Large Phenotypic and Genetic Diversity of Prophages Induced from the Fish Pathogen Vibrio anguillarum. Viruses 2019; 11:v11110983. [PMID: 31653117 PMCID: PMC6893619 DOI: 10.3390/v11110983] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 10/15/2019] [Indexed: 01/07/2023] Open
Abstract
Vibrio anguillarum is a marine pathogenic bacterium that causes vibriosis in fish and shellfish. Although prophage-like sequences have been predicted in V. anguillarum strains, many are not characterized, and it is not known if they retain the functional capacity to form infectious particles that can infect and lysogenize other bacterial hosts. In this study, the genome sequences of 28 V. anguillarum strains revealed 55 different prophage-related elements. Chemical and spontaneous induction allowed a collection of 42 phage isolates, which were classified in seven different groups according to a multiplex PCR assay. One shared prophage sequence, p41 (group III), was present in 17 V. anguillarum strains, suggesting that this specific element is very dynamically exchanged among V. anguillarum populations. Interestingly, the host range of genetically identical phages was highly dependent on the strains used for proliferation, indicating that phenotypic properties of phages were partly regulated by the host. Finally, experimental evidence displayed that the induced phage ɸVa_90-11-287_p41 was able to lysogenize V. anguillarum strain Ba35, and subsequently spontaneously become released from the lysogenized cells, demonstrating an efficient transfer of the phage among V. anguillarum strains. Altogether, the results showed large genetic and functional diversity and broad distribution of prophages in V. anguillarum, and demonstrated the potential of prophages as drivers of evolution in V. anguillarum strains.
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185
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Reis-Cunha JL, Bartholomeu DC, Manson AL, Earl AM, Cerqueira GC. ProphET, prophage estimation tool: A stand-alone prophage sequence prediction tool with self-updating reference database. PLoS One 2019; 14:e0223364. [PMID: 31577829 PMCID: PMC6774505 DOI: 10.1371/journal.pone.0223364] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 09/19/2019] [Indexed: 01/18/2023] Open
Abstract
Background Prophages play a significant role in prokaryotic evolution, often altering the function of the cell that they infect via transfer of new genes e.g., virulence or antibiotic resistance factors, inactivation of existing genes or by modifying gene expression. Recently, phage therapy has gathered renewed interest as a promising alternative to control bacterial infections. Cataloging the repertoire of prophages in large collections of species’ genomes is an important initial step in understanding their evolution and potential therapeutic utility. However, current widely-used tools for identifying prophages within bacterial genome sequences are mainly web-based, can have long response times, and do not scale to keep pace with the many thousands of genomes currently being sequenced routinely. Methodology In this work, we present ProphET, an easy to install prophage predictor to be used in Linux operation system, without the constraints associated with a web-based tool. ProphET predictions rely on similarity searches against a database of prophage genes, taking as input a bacterial genome sequence in FASTA format and its corresponding gene annotation in GFF. ProphET identifies prophages in three steps: similarity search, calculation of the density of prophage genes, and edge refinement. ProphET performance was evaluated and compared with other phage predictors based on a set of 54 bacterial genomes containing 267 manually annotated prophages. Findings and conclusions ProphET identifies prophages in bacterial genomes with high precision and offers a fast, highly scalable alternative to widely-used web-based applications for prophage detection.
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Affiliation(s)
- João L. Reis-Cunha
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
- * E-mail: (JLR-C); (GCC)
| | - Daniella C. Bartholomeu
- Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Abigail L. Manson
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Ashlee M. Earl
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - Gustavo C. Cerqueira
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- Personal Genome Diagnostics, Baltimore, Maryland, United States of America
- * E-mail: (JLR-C); (GCC)
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186
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Wynands B, Otto M, Runge N, Preckel S, Polen T, Blank LM, Wierckx N. Streamlined Pseudomonas taiwanensis VLB120 Chassis Strains with Improved Bioprocess Features. ACS Synth Biol 2019; 8:2036-2050. [PMID: 31465206 DOI: 10.1021/acssynbio.9b00108] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Microbes harbor many traits that are dispensable or even unfavorable under industrial and laboratory settings. The elimination of such traits could improve the host's efficiency, genetic stability, and robustness, thereby increasing the predictability and boosting its performance as a microbial cell factory. We engineered solvent-tolerant Pseudomonas taiwanensis VLB120 to yield streamlined chassis strains with higher growth rates and biomass yields, enhanced solvent tolerance, and improved process performance. In total, the genome was reduced by up to 10%. This was achieved by the elimination of genes that enable the cell to swim and form biofilms and by the deletion of the megaplasmid pSTY and large proviral segments. The resulting strain GRC1 had a 15% higher growth rate and biomass yield than the wildtype. However, this strain lacks the pSTY-encoded efflux pump TtgGHI, rendering it solvent-sensitive. Through reintegration of ttgGHI by chromosomal insertion without (GRC2) and with (GRC3) the corresponding regulator genes, the solvent-tolerant phenotype was enhanced. The generated P. taiwanensis GRC strains enlarge the repertoire of streamlined chassis with enhanced key performance indicators, making them attractive hosts for biotechnological applications. The different solvent tolerance levels of GRC1, GRC2, and GRC3 enable the selection of a fitting host platform in relation to the desired process requirements in a chassis à la carte principle. This was demonstrated in a metabolic engineering approach for the production of phenol from glycerol. The streamlined producer GRC1Δ5-TPL38 outperformed the equivalent nonstreamlined producer VLB120Δ5-TPL38 concerning phenol titer, rate, and yield, thereby highlighting the added value of the streamlined chassis.
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Affiliation(s)
- Benedikt Wynands
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Maike Otto
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Nadine Runge
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Sarah Preckel
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Tino Polen
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Lars M. Blank
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
| | - Nick Wierckx
- Institute of Applied Microbiology, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany
- Institute of Bio- and Geosciences, IBG-1: Biotechnology, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
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187
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Characterization of LysBC17, a Lytic Endopeptidase from Bacillus cereus. Antibiotics (Basel) 2019; 8:antibiotics8030155. [PMID: 31546935 PMCID: PMC6784087 DOI: 10.3390/antibiotics8030155] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 09/16/2019] [Accepted: 09/17/2019] [Indexed: 12/26/2022] Open
Abstract
Bacillus cereus, a Gram-positive bacterium, is an agent of food poisoning. B. cereus is closely related to Bacillus anthracis, a deadly pathogen for humans, and Bacillus thuringenesis, an insect pathogen. Due to the growing prevalence of antibiotic resistance in bacteria, alternative antimicrobials are needed. One such alternative is peptidoglycan hydrolase enzymes, which can lyse Gram-positive bacteria when exposed externally. A bioinformatic search for bacteriolytic enzymes led to the discovery of a gene encoding an endolysin-like endopeptidase, LysBC17, which was then cloned from the genome of B. cereus strain Bc17. This gene is also present in the B. cereus ATCC 14579 genome. The gene for LysBC17 encodes a protein of 281 amino acids. Recombinant LysBC17 was expressed and purified from E. coli. Optimal lytic activity against B. cereus occurred between pH 7.0 and 8.0, and in the absence of NaCl. The LysBC17 enzyme had lytic activity against strains of B. cereus, B. anthracis, and other Bacillus species.
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188
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Sinha A, Maurice CF. Bacteriophages: Uncharacterized and Dynamic Regulators of the Immune System. Mediators Inflamm 2019; 2019:3730519. [PMID: 31582898 PMCID: PMC6754933 DOI: 10.1155/2019/3730519] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 08/06/2019] [Indexed: 12/23/2022] Open
Abstract
The human gut is an extremely active immunological site interfacing with the densest microbial community known to colonize the human body, the gut microbiota. Despite tremendous advances in our comprehension of how the gut microbiota is involved in human health and interacts with the mammalian immune system, most studies are incomplete as they typically do not consider bacteriophages. These bacterial viruses are estimated to be as numerous as their bacterial hosts, with tremendous and mostly uncharacterized genetic diversity. In addition, bacteriophages are not passive members of the gut microbiota, as highlighted by the recent evidence for their active involvement in human health. Yet, how bacteriophages interact with their bacterial hosts and the immune system in the human gut remains poorly described. Here, we aim to fill this gap by providing an overview of bacteriophage communities in the gut during human development, detailing recent findings for their bacterial-mediated effects on the immune response and summarizing the latest evidence for direct interactions between them and the immune system. The dramatic increase in antibiotic-resistant bacterial pathogens has spurred a renewed interest in using bacteriophages for therapy, despite the many unknowns about bacteriophages in the human body. Going forward, more studies encompassing the communities of bacteria, bacteriophages, and the immune system in diverse health and disease settings will provide invaluable insight into this dynamic trio essential for human health.
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Affiliation(s)
- Anshul Sinha
- Department of Microbiology & Immunology, McGill University, Montreal, QC, Canada
| | - Corinne F. Maurice
- Department of Microbiology & Immunology, McGill University, Montreal, QC, Canada
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189
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Liu X, Tang K, Zhang D, Li Y, Liu Z, Yao J, Wood TK, Wang X. Symbiosis of a P2‐family phage and deep‐sea
Shewanella putrefaciens. Environ Microbiol 2019; 21:4212-4232. [DOI: 10.1111/1462-2920.14781] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Revised: 07/12/2019] [Accepted: 08/13/2019] [Indexed: 11/30/2022]
Affiliation(s)
- Xiaoxiao Liu
- Key Laboratory of Tropical Marine Bio‐resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences Guangzhou 510301 China
| | - Kaihao Tang
- Key Laboratory of Tropical Marine Bio‐resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences Guangzhou 510301 China
| | - Dali Zhang
- Key Laboratory of Tropical Marine Bio‐resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences Guangzhou 510301 China
| | - Yangmei Li
- Key Laboratory of Tropical Marine Bio‐resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences Guangzhou 510301 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Zhe Liu
- Guangdong Provincial Center for Disease Control and Prevention Guangdong Provincial Institute of Public Health Guangzhou 511430 China
| | - Jianyun Yao
- Key Laboratory of Tropical Marine Bio‐resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences Guangzhou 510301 China
| | - Thomas K. Wood
- Department of Chemical Engineering Pennsylvania State University University Park PA 16802‐4400 USA
| | - Xiaoxue Wang
- Key Laboratory of Tropical Marine Bio‐resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences Guangzhou 510301 China
- University of Chinese Academy of Sciences Beijing 100049 China
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190
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Tang Q, Feng M, Hou B, Ye J, Wu H, Zhang H. Prophage protein RacR activates lysozyme LysN, causing the growth defect of E. coli JM83. Sci Rep 2019; 9:12537. [PMID: 31467306 PMCID: PMC6715736 DOI: 10.1038/s41598-019-48690-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 08/01/2019] [Indexed: 11/09/2022] Open
Abstract
Prophage enriched the prokaryotic genome, and their transcriptional factors improved the protein expression network of the host. In this study, we uncovered a new prophage-prophage interaction in E. coli JM83. The Rac prophage protein RacR (GenBank accession no. AVI55875.1) directly activated the transcription of φ80dlacZΔM15 prophage lysozyme encoding gene 19 (GenBank accession no. ACB02445.1, renamed it lysN, lysozyme nineteen), resulting in the growth defect of JM83. This phenomenon also occurred in DH5α, but not in BL21(DE3) and MG1655 due to the genotype differences. However, deletion of lysN could not completely rescued JM83 from the growth arrest, indicating that RacR may regulate other related targets. In addition, passivation of RacR regulation was found in the late period of growth of JM83, and it was transmissible to daughter cells. Altogether, our study revealed part of RacR regulatory network, which suggested some advanced genetic strategies in bacteria.
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Affiliation(s)
- Qiongwei Tang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Meilin Feng
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Bingbing Hou
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Jiang Ye
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Haizhen Wu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China. .,Department of Applied Biology, East China University of Science and Technology, Shanghai, China.
| | - Huizhan Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China. .,Department of Applied Biology, East China University of Science and Technology, Shanghai, China.
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191
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Generation of a Prophage-Free Variant of the Fast-Growing Bacterium Vibrio natriegens. Appl Environ Microbiol 2019; 85:AEM.00853-19. [PMID: 31253674 PMCID: PMC6696956 DOI: 10.1128/aem.00853-19] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 06/19/2019] [Indexed: 12/16/2022] Open
Abstract
The fast-growing marine bacterium Vibrio natriegens represents an emerging strain for molecular biology and biotechnology. Genome sequencing and quantitative PCR analysis revealed that the first chromosome of V. natriegens ATCC 14048 contains two prophage regions (VNP1 and VNP2) that are both inducible by the DNA-damaging agent mitomycin C and exhibit spontaneous activation under standard cultivation conditions. Their activation was also confirmed by live cell imaging of an mCherry fusion to the major capsid proteins of VNP1 and VNP2. Transmission electron microscopy visualized the release of phage particles belonging to the Siphoviridae family into the culture supernatant. Freeing V. natriegens from its proviral load, followed by phenotypic characterization, revealed an improved robustness of the prophage-free variant toward DNA-damaging conditions, reduced cell lysis under hypo-osmotic conditions, and an increased pyruvate production compared to wild-type levels. Remarkably, the prophage-free strain outcompeted the wild type in a competitive growth experiment, emphasizing that this strain is a promising platform for future metabolic engineering approaches.IMPORTANCE The fast-growing marine bacterium Vibrio natriegens represents an emerging model host for molecular biology and biotechnology, featuring a reported doubling time of less than 10 minutes. In many bacterial species, viral DNA (prophage elements) may constitute a considerable fraction of the whole genome and may have detrimental effects on the growth and fitness of industrial strains. Genome analysis revealed the presence of two prophage regions in the V. natriegens genome that were shown to undergo spontaneous induction under standard cultivation conditions. In this study, we generated a prophage-free variant of V. natriegens Remarkably, the prophage-free strain exhibited a higher tolerance toward DNA damage and hypo-osmotic stress. Moreover, it was shown to outcompete the wild-type strain in a competitive growth experiment. In conclusion, our study presents the prophage-free variant of V. natriegens as a promising platform strain for future biotechnological applications.
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192
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Rands CM, Brüssow H, Zdobnov EM. Comparative genomics groups phages of Negativicutes and classical Firmicutes despite different Gram-staining properties. Environ Microbiol 2019; 21:3989-4001. [PMID: 31314945 DOI: 10.1111/1462-2920.14746] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 07/02/2019] [Accepted: 07/14/2019] [Indexed: 01/05/2023]
Abstract
Negativicutes are gram-negative bacteria characterized by two cell membranes, but they are phylogenetically a side-branch of gram-positive Firmicutes that contain only a single membrane. We asked whether viruses (phages) infecting Negativicutes were horizontally acquired from gram-negative Proteobacteria, given the shared outer cell structure of their bacterial hosts, or if Negativicute phages co-evolved vertically with their hosts and thus resemble gram-positive Firmicute prophages. We predicted and characterized 485 prophages (mostly Caudovirales) from gram-negative Firmicute genomes plus 2977 prophages from other bacterial clades, and we used virome sequence data from 183 human stool samples to support our predictions. The majority of identified Negativicute prophages were lambdoids closer related to prophages from other Firmicutes than Proteobacteria by sequence relationship and genome organization (position of the lysis module). Only a single Mu-like candidate prophage and no clear P2-like prophages were identified in Negativicutes, both common in Proteobacteria. Given this collective evidence, it is unlikely that Negativicute phages were acquired from Proteobacteria. Sequence-related prophages, which occasionally harboured antibiotic resistance genes, were identified in two distinct Negativicute orders (Veillonellales and Acidaminococcales), possibly suggesting horizontal cross-order phage infection between human gut commensals. Our results reveal ancient genomic signatures of phage and bacteria co-evolution despite horizontal phage mobilization.
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Affiliation(s)
- Chris M Rands
- Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland.,Swiss Institute of Bioinformatics, Geneva, Switzerland
| | - Harald Brüssow
- Department of Biosystems, Laboratory of Gene Technology, KU Leuven, Leuven, Belgium
| | - Evgeny M Zdobnov
- Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland.,Swiss Institute of Bioinformatics, Geneva, Switzerland
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193
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Shimada T, Ogasawara H, Ishihama A. Single-target regulators form a minor group of transcription factors in Escherichia coli K-12. Nucleic Acids Res 2019. [PMID: 29529243 PMCID: PMC5934670 DOI: 10.1093/nar/gky138] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The identification of regulatory targets of all TFs is critical for understanding the entire network of the genome regulation. The lac regulon of Escherichia coli K-12 W3110 is composed of the lacZYA operon and its repressor lacI gene, and has long been recognized as the seminal model of transcription regulation in bacteria with only one highly preferred target. After the Genomic SELEX screening in vitro of more than 200 transcription factors (TFs) from E. coli K-12, however, we found that most TFs regulate multiple target genes. With respect to the number of regulatory targets, a total of these 200 E. coli TFs form a hierarchy ranging from a single target to as many as 1000 targets. Here we focus a total of 13 single-target TFs, 9 known TFs (BetI, KdpE, LacI, MarR, NanR, RpiR, TorR, UlaR and UxuR) and 4 uncharacterized TFs (YagI, YbaO, YbiH and YeaM), altogether forming only a minor group of TFs in E. coli. These single-target TFs were classified into three groups based on their functional regulation.
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Affiliation(s)
- Tomohiro Shimada
- Meiji University, School of Agriculture, Kawasaki, Kanagawa 214-8571, Japan
| | - Hiroshi Ogasawara
- Shinshu University, Research Center for Supports to Advanced Science, Division of Gene Research, Ueda, Nagano 386-8567, Japan.,Shinshu University, Research Center for Fungal and Microbial Dynamism, Kamiina, Nagano 399-4598, Japan
| | - Akira Ishihama
- Hosei University, Micro-Nano Technology Research Center, Koganei, Tokyo 184-8584, Japan
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194
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Stevens RH, Zhang H, Sedgley C, Bergman A, Manda AR. The prevalence and impact of lysogeny among oral isolates of Enterococcus faecalis. J Oral Microbiol 2019; 11:1643207. [PMID: 31489125 PMCID: PMC6711143 DOI: 10.1080/20002297.2019.1643207] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 07/01/2019] [Accepted: 07/03/2019] [Indexed: 10/29/2022] Open
Abstract
Bacterial phenotypic properties are frequently influenced by the uptake of extrachromosomal genetic elements, such as plasmids and bacteriophage genomes. Such modifications can result in enhanced pathogenicity due to toxin production, increased toxin release, altered antigenicity, and resistance to antibiotics. In the case of bacteriophages, the phage genome can stably integrate into the bacterial chromosome as a prophage, to produce a lysogenic cell. Oral enterococcal strains have been isolated from subgingival plaque and the root canals of endodontically-treated teeth that have failed to heal. Previously, we isolated a bacteriophage, phage ɸEf11, induced from a lysogenic Enterococcus faecalis strain recovered from the root canal of a failed endodontic case. PCR analysis using phage ɸEf11-specific oligonucleotide primers, disclosed that lysogens containing ɸEf11 prophages were commonly found among oral E. faecalis strains, being detected in 19 of 61 (31%) strains examined. Furthermore, in comparison to an isogenic cured strain, cultures of a lysogen harboring an ɸEf11 prophage exhibited altered phenotypic characteristics, such as increased persistence at high density, enhanced biofilm formation, and resistance to a bacteriophage lytic enzyme. From these results we conclude that lysogeny is common among oral E. faecalis strains, and that it alters properties of the lysogenic cell.
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Affiliation(s)
- Roy H Stevens
- Kornberg School of Dentistry, Temple University, Philadelphia, PA, USA
| | - Hongming Zhang
- Kornberg School of Dentistry, Temple University, Philadelphia, PA, USA
| | - Christine Sedgley
- Department of Endodontology, Oregon Health and Science University, Portland, OR, USA
| | - Adam Bergman
- Kornberg School of Dentistry, Temple University, Philadelphia, PA, USA
| | - Anil Reddy Manda
- Kornberg School of Dentistry, Temple University, Philadelphia, PA, USA
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195
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orf20 in prophage phiv142-3 contributes to the adhesion and colonization ability of avian pathogenic Escherichia coli strain DE142 by affecting the formation of flagella and I fimbriae. Vet Microbiol 2019; 235:301-309. [PMID: 31383317 DOI: 10.1016/j.vetmic.2019.07.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 07/17/2019] [Accepted: 07/20/2019] [Indexed: 12/21/2022]
Abstract
We have previously demonstrated that prophage phiv142-3 enhances the colonization ability of avian pathogenic Escherichia coli (APEC) strain DE142. However, the mechanism of this action remains unknown. In this study, we demonstrate that deletion of phiv142-3 orf20 leads to a decrease in the survival ability in chicken serum, adhesion, and ability to invade DF-1 cells of mutant strain DE142Δorf20 compared with that of wild type (WT). Avian infection assays showed that bacterial loads in lungs and hearts of chickens challenged with the mutant are decreased to 7% and 8.3% compared with those challenged with the WT. The number of flagella and I fimbriae of the mutant are decreased and the mutant exhibits filamentation. However, protein ORF20 shows no adhesion ability to DF-1 cells in adherence inhibition experiments, indicating that it does not directly participate in adhesion. qRT-PCR revealed that the deletion of orf20 leads to reduction in the expression of nine genes related to the exportation of flagellar protein and two I-fimbriae-related genes (fimA and fimH), but does not affect genes related to the synthesis of flagella and other adhesins. Compared with the WT, the transcription level of the cell-division-associated genes minC and minD was increased 1.4-fold and 2.5-fold in mutant DE142Δorf20, respectively, indicating that orf20 affects the morphology of DE142 by regulating expression of minC and minD. Thus, our study revealed that orf20 in prophage phiv142-3 played a role in flagellar exportation, cell morphology, and I fimbriae synthesis.
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196
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Labonté JM, Pachiadaki M, Fergusson E, McNichol J, Grosche A, Gulmann LK, Vetriani C, Sievert SM, Stepanauskas R. Single Cell Genomics-Based Analysis of Gene Content and Expression of Prophages in a Diffuse-Flow Deep-Sea Hydrothermal System. Front Microbiol 2019; 10:1262. [PMID: 31244796 PMCID: PMC6581674 DOI: 10.3389/fmicb.2019.01262] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 05/21/2019] [Indexed: 11/25/2022] Open
Abstract
Phage–host interactions likely play a major role in the composition and functioning of many microbiomes, yet remain poorly understood. Here, we employed single cell genomics to investigate phage–host interactions in a diffuse-flow, low-temperature hydrothermal vent that may be reflective of a broadly distributed biosphere in the subseafloor. We identified putative prophages in 13 of 126 sequenced single amplified genomes (SAGs), with no evidence for lytic infections, which is in stark contrast to findings in the surface ocean. Most were distantly related to known prophages, while their hosts included bacterial phyla Campylobacterota, Bacteroidetes, Chlorobi, Proteobacteria, Lentisphaerae, Spirochaetes, and Thermotogae. Our results suggest the predominance of lysogeny over lytic interaction in diffuse-flow, deep-sea hydrothermal vents, despite the high activity of the dominant Campylobacteria that would favor lytic infections. We show that some of the identified lysogens have co-evolved with their host over geological time scales and that their genes are transcribed in the environment. Functional annotations of lysogeny-related genes suggest involvement in horizontal gene transfer enabling host’s protection against toxic metals and antibacterial compounds.
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Affiliation(s)
- Jessica M Labonté
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, United States.,Department of Marine Biology, Texas A&M University at Galveston, Galveston, TX, United States
| | - Maria Pachiadaki
- Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, United States.,Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
| | | | - Jesse McNichol
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
| | - Ashley Grosche
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ, United States
| | - Lara K Gulmann
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
| | - Costantino Vetriani
- Department of Biochemistry and Microbiology, Rutgers University, New Brunswick, NJ, United States.,Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, NJ, United States
| | - Stefan M Sievert
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, United States
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197
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Fang Z, Tan J, Wu S, Li M, Xu C, Xie Z, Zhu H. PPR-Meta: a tool for identifying phages and plasmids from metagenomic fragments using deep learning. Gigascience 2019; 8:giz066. [PMID: 31220250 PMCID: PMC6586199 DOI: 10.1093/gigascience/giz066] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 03/26/2019] [Accepted: 05/14/2019] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Phages and plasmids are the major components of mobile genetic elements, and fragments from such elements generally co-exist with chromosome-derived fragments in sequenced metagenomic data. However, there is a lack of efficient methods that can simultaneously identify phages and plasmids in metagenomic data, and the existing tools identifying either phages or plasmids have not yet presented satisfactory performance. FINDINGS We present PPR-Meta, a 3-class classifier that allows simultaneous identification of both phage and plasmid fragments from metagenomic assemblies. PPR-Meta consists of several modules for predicting sequences of different lengths. Using deep learning, a novel network architecture, referred to as the Bi-path Convolutional Neural Network, is designed to improve the performance for short fragments. PPR-Meta demonstrates much better performance than currently available similar tools individually for phage or plasmid identification, while testing on both artificial contigs and real metagenomic data. PPR-Meta is freely available via http://cqb.pku.edu.cn/ZhuLab/PPR_Meta or https://github.com/zhenchengfang/PPR-Meta. CONCLUSIONS To the best of our knowledge, PPR-Meta is the first tool that can simultaneously identify phage and plasmid fragments efficiently and reliably. The software is optimized and can be easily run on a local PC by non-computer professionals. We developed PPR-Meta to promote the research on mobile genetic elements and horizontal gene transfer.
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Affiliation(s)
- Zhencheng Fang
- State Key Laboratory for Turbulence and Complex Systems and Department of Biomedical Engineering, College of Engineering, Peking University, No.5 Yiheyuan Road Haidian District, Beijing 100871, China
- Center for Quantitative Biology, Peking University, No.5 Yiheyuan Road Haidian District, Beijing 100871, China
| | - Jie Tan
- State Key Laboratory for Turbulence and Complex Systems and Department of Biomedical Engineering, College of Engineering, Peking University, No.5 Yiheyuan Road Haidian District, Beijing 100871, China
- Center for Quantitative Biology, Peking University, No.5 Yiheyuan Road Haidian District, Beijing 100871, China
| | - Shufang Wu
- State Key Laboratory for Turbulence and Complex Systems and Department of Biomedical Engineering, College of Engineering, Peking University, No.5 Yiheyuan Road Haidian District, Beijing 100871, China
- Center for Quantitative Biology, Peking University, No.5 Yiheyuan Road Haidian District, Beijing 100871, China
| | - Mo Li
- State Key Laboratory for Turbulence and Complex Systems and Department of Biomedical Engineering, College of Engineering, Peking University, No.5 Yiheyuan Road Haidian District, Beijing 100871, China
- Center for Quantitative Biology, Peking University, No.5 Yiheyuan Road Haidian District, Beijing 100871, China
- Peking University-Tsinghua University - National Institute of Biological Sciences (PTN) joint PhD program, School of Life Sciences, Peking University, No.5 Yiheyuan Road Haidian District, Beijing 100871, China
| | - Congmin Xu
- State Key Laboratory for Turbulence and Complex Systems and Department of Biomedical Engineering, College of Engineering, Peking University, No.5 Yiheyuan Road Haidian District, Beijing 100871, China
- Center for Quantitative Biology, Peking University, No.5 Yiheyuan Road Haidian District, Beijing 100871, China
- Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 631 Cherry St, Atlanta, Georgia 30332, GA, USA
| | - Zhongjie Xie
- State Key Laboratory for Turbulence and Complex Systems and Department of Biomedical Engineering, College of Engineering, Peking University, No.5 Yiheyuan Road Haidian District, Beijing 100871, China
- Center for Quantitative Biology, Peking University, No.5 Yiheyuan Road Haidian District, Beijing 100871, China
| | - Huaiqiu Zhu
- State Key Laboratory for Turbulence and Complex Systems and Department of Biomedical Engineering, College of Engineering, Peking University, No.5 Yiheyuan Road Haidian District, Beijing 100871, China
- Center for Quantitative Biology, Peking University, No.5 Yiheyuan Road Haidian District, Beijing 100871, China
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198
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Liang J, Kou Z, Qin S, Chen Y, Li Z, Li C, Duan R, Hao H, Zha T, Gu W, Huang Y, Xiao M, Jing H, Wang X. Novel Yersinia enterocolitica Prophages and a Comparative Analysis of Genomic Diversity. Front Microbiol 2019; 10:1184. [PMID: 31191498 PMCID: PMC6548840 DOI: 10.3389/fmicb.2019.01184] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 05/09/2019] [Indexed: 12/18/2022] Open
Abstract
Yersinia enterocolitica is a major agent of foodborne diseases worldwide. Prophage plays an important role in the genetic evolution of the bacterial genome. Little is known about the genetic information about prophages in the genome of Y. enterocolitica, and no pathogenic Y. enterocolitica prophages have been described. In this study, we induced and described the genomes of six prophages from pathogenic Y. enterocolitica for the first time. Phylogenetic analysis based on whole genome sequencing revealed that these novel Yersinia phages are genetically distinct from the previously reported phages, showing considerable genetic diversity. Interestingly, the prophages induced from O:3 and O:9 Y. enterocolitica showed different genomic sequences and morphology but highly conserved among the same serotype strains, which classified into two diverse clusters. The three long-tailed Myoviridae prophages induced from serotype O:3 Y. enterocolitica were highly conserved, shared ≥99.99% identity and forming genotypic cluster A; the three Podoviridae prophages induced from the serotype O:9 strains formed cluster B, also shared more than 99.90% identity with one another. Cluster A was most closely related to O:5 non-pathogenic Y. enterocolitica prophage PY54 (61.72% identity). The genetic polymorphism of these two kinds of prophages and highly conserved among the same serotype strains, suggested a possible shared evolutionary past for these phages: originated from distinct ancestors, and entered pathogenic Y. enterocolitica as extrachromosomal genetic components during evolution when facing selective pressure. These results are critically important for further understanding of phage roles in host physiology and the pathology of disease.
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Affiliation(s)
- Junrong Liang
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases - Chinese Center for Disease Control and Prevention, National Institute for Communicable Disease Control and Prevention, Beijing, China
| | - Zengqiang Kou
- Shandong Provincial Centre for Disease Control and Prevention, Jinan, China
| | - Shuai Qin
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases - Chinese Center for Disease Control and Prevention, National Institute for Communicable Disease Control and Prevention, Beijing, China
| | - Yuhuang Chen
- Shenzhen Nanshan Maternity and Child Heath Care Hospital, Shenzhen, China
| | - Zhenpeng Li
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases - Chinese Center for Disease Control and Prevention, National Institute for Communicable Disease Control and Prevention, Beijing, China
| | - Chuchu Li
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases - Chinese Center for Disease Control and Prevention, National Institute for Communicable Disease Control and Prevention, Beijing, China.,Department of Pathogenic Biology, School of Medical Science, Jiangsu University, Zhenjiang, China
| | - Ran Duan
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases - Chinese Center for Disease Control and Prevention, National Institute for Communicable Disease Control and Prevention, Beijing, China
| | - Huijing Hao
- Chang Ping Women and Children Health Care Hospital, Beijing, China
| | - Tao Zha
- Wuhu Municipal Centre for Disease Control and Prevention, Wuhu, China
| | - Wenpeng Gu
- Yunnan Provincial Centre for Disease Control and Prevention, Kunming, China
| | - Yuanming Huang
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases - Chinese Center for Disease Control and Prevention, National Institute for Communicable Disease Control and Prevention, Beijing, China
| | - Meng Xiao
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases - Chinese Center for Disease Control and Prevention, National Institute for Communicable Disease Control and Prevention, Beijing, China
| | - Huaiqi Jing
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases - Chinese Center for Disease Control and Prevention, National Institute for Communicable Disease Control and Prevention, Beijing, China
| | - Xin Wang
- State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases - Chinese Center for Disease Control and Prevention, National Institute for Communicable Disease Control and Prevention, Beijing, China
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199
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Minnullina L, Pudova D, Shagimardanova E, Shigapova L, Sharipova M, Mardanova A. Comparative Genome Analysis of Uropathogenic Morganella morganii Strains. Front Cell Infect Microbiol 2019; 9:167. [PMID: 31231616 PMCID: PMC6558430 DOI: 10.3389/fcimb.2019.00167] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 05/03/2019] [Indexed: 12/02/2022] Open
Abstract
Morganella morganii is an opportunistic bacterial pathogen shown to cause a wide range of clinical and community-acquired infections. This study was aimed at sequencing and comparing the genomes of three M. morganii strains isolated from the urine samples of patients with community-acquired urinary tract infections. Draft genome sequencing was conducted using the Illumina HiSeq platform. The genomes of MM 1, MM 4, and MM 190 strains have a size of 3.82–3.97 Mb and a GC content of 50.9–51%. Protein-coding sequences (CDS) represent 96.1% of the genomes, RNAs are encoded by 2.7% of genes and pseudogenes account for 1.2% of the genomes. The pan-genome containes 4,038 CDS, of which 3,279 represent core genes. Six to ten prophages and 21–33 genomic islands were identified in the genomes of MM 1, MM 4, and MM 190. More than 30 genes encode capsular biosynthesis proteins, an average of 60 genes encode motility and chemotaxis proteins, and about 70 genes are associated with fimbrial biogenesis and adhesion. We determined that all strains contained urease gene cluster ureABCEFGD and had a urease activity. Both MM 4 and MM 190 strains are capable of hemolysis and their activity correlates well with a cytotoxicity level on T-24 bladder carcinoma cells. These activities were associated with expression of RTX toxin gene hlyA, which was introduced into the genomes by a phage similar to Salmonella phage 118970_sal4.
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Affiliation(s)
- Leyla Minnullina
- Laboratory of Microbial Biotechnology, Institute of Fundamental Medicine and Biology, Kazan (Volga region) Federal University, Kazan, Russia
| | - Daria Pudova
- Laboratory of Microbial Biotechnology, Institute of Fundamental Medicine and Biology, Kazan (Volga region) Federal University, Kazan, Russia
| | - Elena Shagimardanova
- Laboratory of Extreme Biology, Institute of Fundamental Medicine and Biology, Kazan (Volga region) Federal University, Kazan, Russia
| | - Leyla Shigapova
- Laboratory of Extreme Biology, Institute of Fundamental Medicine and Biology, Kazan (Volga region) Federal University, Kazan, Russia
| | - Margarita Sharipova
- Laboratory of Microbial Biotechnology, Institute of Fundamental Medicine and Biology, Kazan (Volga region) Federal University, Kazan, Russia
| | - Ayslu Mardanova
- Laboratory of Microbial Biotechnology, Institute of Fundamental Medicine and Biology, Kazan (Volga region) Federal University, Kazan, Russia
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200
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Fu Y, Wu Y, Yuan Y, Gao M. Prevalence and Diversity Analysis of Candidate Prophages to Provide An Understanding on Their Roles in Bacillus Thuringiensis. Viruses 2019; 11:v11040388. [PMID: 31027262 PMCID: PMC6521274 DOI: 10.3390/v11040388] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 04/04/2019] [Accepted: 04/24/2019] [Indexed: 01/03/2023] Open
Abstract
Bacillus thuringiensis (Bt) is widely used in producing biological insecticides. Phage contaminations during Bt fermentation can cause severe losses of yields. Lots of strategies have been engaged to control extrinsic phage contamination during Bt fermentation, but their effectiveness is low. In this study, the candidate endogenous prophages (prophages) in 61 Bt chromosomes that had been deposited in GenBank database were analyzed. The results revealed that all chromosomes contained prophage regions, and 398 candidate prophage regions were predicted, including 135 putative complete prophages and 263 incomplete prophage regions. These putative complete prophages showed highly diverse genetic backgrounds. The inducibility of the prophages of ten Bt strains (4AJ1, 4BD1, HD-1, HD-29, HD-73, HD-521, BMB171, 4CC1, CT-43, and HD-1011) was tested, and the results showed that seven of the ten strains’ prophages were inducible. These induced phages belonged to the Siphoviridae family and exhibited a broad host spectrum against the non-original strains. The culture supernatants of the two strains (BMB171, 4CC1) could lyse Bt cells, but no virions were observed, which was speculated to be caused by lysin. The functional analysis of the putative complete prophage proteins indicated that some proteins, such as antibiotic resistance-associated proteins and restriction endonucleases, might increase the fitness of the Bt strains to different environments. The findings of this study provided understanding on the high prevalence and diversity of Bt prophages, as well as pointed out the role of prophages in the life cycle of Bt.
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Affiliation(s)
- Yajuan Fu
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.
- University of Chinese Academy of Sciences, Beijing 100039, China.
| | - Yan Wu
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.
| | - Yihui Yuan
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.
- Present address: State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou 571158, China.
| | - Meiying Gao
- Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.
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