1
|
Lehman SM, Kongari R, Glass AM, Koert M, Ray MD, Plaut RD, Stibitz S. Phage K gp102 Drives Temperature-Sensitive Antibacterial Activity on USA300 MRSA. Viruses 2022; 15:17. [PMID: 36680060 PMCID: PMC9861931 DOI: 10.3390/v15010017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 12/15/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022] Open
Abstract
There is widespread interest in using obligately lytic bacteriophages ("phages") to treat human bacterial infections. Among Staphylococcus aureus infections, the USA300 lineage is a frequent cause of invasive disease. We observed that phage K, a model S. aureus myophage, exhibits temperature-sensitive growth on USA300 strains, with the wild-type phage providing poorer growth suppression in broth and forming smaller and fainter plaques at 37 °C vs. 30 °C. We isolated 65 mutants of phage K that had improved plaquing characteristics at 37 °C when compared to the parental phage. In all 65 mutants, this phenotype was attributable to loss-of-function (LoF) mutations in gp102, which encodes a protein of unknown function that has homologs only among the Herelleviridae (SPO1-like myophages infecting gram-positive bacteria). Additional experiments with representative mutants consistently showed that the temperature-sensitive plaque phenotype was specific to USA300 MRSA strains and that Gp102 disruption was correlated with improved suppression of bacterial growth in broth and improved antibacterial activity in a mouse model of upper respiratory tract infection. The same genotype and in vitro phenotypes could be replicated in close relatives of phage K. Gp102 disruption did not have a detectable effect on adsorption but did delay cell culture lysis relative to wild-type under permissive infection conditions, suggesting that gp102 conservation might be maintained by selective pressure for more rapid replication. Expression of gp102 on a plasmid was toxic to both an MSSA and a USA300 MRSA strain. Molecular modeling predicts a protein with two helix-turn-helix domains that displays some similarity to DNA-binding proteins such as transcription factors. While its function remains unclear, gp102 is a conserved gene that is important to the infection process of Kayvirus phages, and it appears that the manner in which USA300 strains defend against them at 37 °C can be overcome by gp102 LoF mutations.
Collapse
|
2
|
Pavlin A, Lovše A, Bajc G, Otoničar J, Kujović A, Lengar Ž, Gutierrez-Aguirre I, Kostanjšek R, Konc J, Fornelos N, Butala M. A small bacteriophage protein determines the hierarchy over co-residential jumbo phage in Bacillus thuringiensis serovar israelensis. Commun Biol 2022; 5:1286. [PMID: 36434275 PMCID: PMC9700832 DOI: 10.1038/s42003-022-04238-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 11/08/2022] [Indexed: 11/26/2022] Open
Abstract
Bacillus thuringiensis serovar israelensis is the most widely used biopesticide against insects, including vectors of animal and human diseases. Among several extrachromosomal elements, this endospore-forming entomopathogen harbors two bacteriophages: a linear DNA replicon named GIL01 that does not integrate into the chromosome during lysogeny and a circular-jumbo prophage known as pBtic235. Here, we show that GIL01 hinders the induction of cohabiting prophage pBtic235. The GIL01-encoded small protein, gp7, which interacts with the host LexA repressor, is a global transcription regulator and represses the induction of pBtic235 after DNA damage to presumably allow GIL01 to multiply first. In a complex with host LexA in stressed cells, gp7 down-regulates the expression of more than 250 host and pBtic235 genes, many of which are involved in the cellular functions of genome maintenance, cell-wall transport, and membrane and protein stability. We show that gp7 homologs that are found exclusively in bacteriophages act in a similar fashion to enhance LexA's binding to DNA, while likely also affecting host gene expression. Our results provide evidence that GIL01 influences both its host and its co-resident bacteriophage.
Collapse
Affiliation(s)
- Anja Pavlin
- grid.8954.00000 0001 0721 6013Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Anže Lovše
- grid.8954.00000 0001 0721 6013Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia ,Genialis, Inc., Boston, MA USA
| | - Gregor Bajc
- grid.8954.00000 0001 0721 6013Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Jan Otoničar
- grid.8954.00000 0001 0721 6013Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Amela Kujović
- grid.8954.00000 0001 0721 6013Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Živa Lengar
- grid.419523.80000 0004 0637 0790Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
| | - Ion Gutierrez-Aguirre
- grid.419523.80000 0004 0637 0790Department of Biotechnology and Systems Biology, National Institute of Biology, Ljubljana, Slovenia
| | - Rok Kostanjšek
- grid.8954.00000 0001 0721 6013Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| | - Janez Konc
- grid.454324.00000 0001 0661 0844Theory Department, National Institute of Chemistry, Ljubljana, Slovenia
| | - Nadine Fornelos
- grid.66859.340000 0004 0546 1623Broad Institute of MIT and Harvard, Cambridge, MA USA
| | - Matej Butala
- grid.8954.00000 0001 0721 6013Department of Biology, Biotechnical Faculty, University of Ljubljana, Ljubljana, Slovenia
| |
Collapse
|
3
|
Unraveling Protein Interactions between the Temperate Virus Bam35 and Its Bacillus Host Using an Integrative Yeast Two Hybrid-High Throughput Sequencing Approach. Int J Mol Sci 2021; 22:ijms222011105. [PMID: 34681765 PMCID: PMC8539640 DOI: 10.3390/ijms222011105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 10/08/2021] [Accepted: 10/10/2021] [Indexed: 11/20/2022] Open
Abstract
Bacillus virus Bam35 is the model Betatectivirus and member of the family Tectiviridae, which is composed of tailless, icosahedral, and membrane-containing bacteriophages. Interest in these viruses has greatly increased in recent years as they are thought to be an evolutionary link between diverse groups of prokaryotic and eukaryotic viruses. Additionally, betatectiviruses infect bacteria of the Bacillus cereus group, which are known for their applications in industry and notorious since it contains many pathogens. Here, we present the first protein–protein interactions (PPIs) network for a tectivirus–host system by studying the Bam35–Bacillus thuringiensis model using a novel approach that integrates the traditional yeast two-hybrid system and high-throughput sequencing (Y2H-HTS). We generated and thoroughly analyzed a genomic library of Bam35′s host B. thuringiensis HER1410 and screened interactions with all the viral proteins using different combinations of bait–prey couples. Initial analysis of the raw data enabled the identification of over 4000 candidate interactions, which were sequentially filtered to produce 182 high-confidence interactions that were defined as part of the core virus–host interactome. Overall, host metabolism proteins and peptidases were particularly enriched within the detected interactions, distinguishing this host–phage system from the other reported host–phage PPIs. Our approach also suggested biological roles for several Bam35 proteins of unknown function, including the membrane structural protein P25, which may be a viral hub with a role in host membrane modification during viral particle morphogenesis. This work resulted in a better understanding of the Bam35–B. thuringiensis interaction at the molecular level and holds great potential for the generalization of the Y2H-HTS approach for other virus–host models.
Collapse
|
4
|
Brady A, Felipe-Ruiz A, Gallego Del Sol F, Marina A, Quiles-Puchalt N, Penadés JR. Molecular Basis of Lysis-Lysogeny Decisions in Gram-Positive Phages. Annu Rev Microbiol 2021; 75:563-581. [PMID: 34343015 DOI: 10.1146/annurev-micro-033121-020757] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Temperate bacteriophages (phages) are viruses of bacteria. Upon infection of a susceptible host, a temperate phage can establish either a lytic cycle that kills the host or a lysogenic cycle as a stable prophage. The life cycle pursued by an infecting temperate phage can have a significant impact not only on the individual host bacterium at the cellular level but also on bacterial communities and evolution in the ecosystem. Thus, understanding the decision processes of temperate phages is crucial. This review delves into the molecular mechanisms behind lysis-lysogeny decision-making in Gram-positive phages. We discuss a variety of molecular mechanisms and the genetic organization of these well-understood systems. By elucidating the strategies used by phages to make lysis-lysogeny decisions, we can improve our understanding of phage-host interactions, which is crucial for a variety of studies including bacterial evolution, community and ecosystem diversification, and phage therapeutics. Expected final online publication date for the Annual Review of Microbiology, Volume 75 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
Collapse
Affiliation(s)
- Aisling Brady
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8TA, United Kingdom;
| | - Alonso Felipe-Ruiz
- Instituto de Biomedicina de Valencia, Consejo Superior de Investigaciones Científicas (IBV-CSIC), and Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 46010 Valencia, Spain;
| | - Francisca Gallego Del Sol
- Instituto de Biomedicina de Valencia, Consejo Superior de Investigaciones Científicas (IBV-CSIC), and Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 46010 Valencia, Spain;
| | - Alberto Marina
- Instituto de Biomedicina de Valencia, Consejo Superior de Investigaciones Científicas (IBV-CSIC), and Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), 46010 Valencia, Spain;
| | - Nuria Quiles-Puchalt
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8TA, United Kingdom;
| | - José R Penadés
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8TA, United Kingdom; .,MRC Centre for Molecular Bacteriology and Infection, Imperial College London, London SW7 2AZ, United Kingdom;
| |
Collapse
|
5
|
Lechuga A, Kazlauskas D, Salas M, Redrejo-Rodríguez M. Unlimited Cooperativity of Betatectivirus SSB, a Novel DNA Binding Protein Related to an Atypical Group of SSBs From Protein-Primed Replicating Bacterial Viruses. Front Microbiol 2021; 12:699140. [PMID: 34267740 PMCID: PMC8276246 DOI: 10.3389/fmicb.2021.699140] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 06/08/2021] [Indexed: 11/20/2022] Open
Abstract
Bam35 and related betatectiviruses are tail-less bacteriophages that prey on members of the Bacillus cereus group. These temperate viruses replicate their linear genome by a protein-primed mechanism. In this work, we have identified and characterized the product of the viral ORF2 as a single-stranded DNA binding protein (hereafter B35SSB). B35SSB binds ssDNA with great preference over dsDNA or RNA in a sequence-independent, highly cooperative manner that results in a non-specific stimulation of DNA replication. We have also identified several aromatic and basic residues, involved in base-stacking and electrostatic interactions, respectively, that are required for effective protein-ssDNA interaction. Although SSBs are essential for DNA replication in all domains of life as well as many viruses, they are very diverse proteins. However, most SSBs share a common structural domain, named OB-fold. Protein-primed viruses could constitute an exception, as no OB-fold DNA binding protein has been reported. Based on databases searches as well as phylogenetic and structural analyses, we showed that B35SSB belongs to a novel and independent group of SSBs. This group contains proteins encoded by protein-primed viral genomes from unrelated viruses, spanning betatectiviruses and Φ29 and close podoviruses, and they share a conserved pattern of secondary structure. Sensitive searches and structural predictions indicate that B35SSB contains a conserved domain resembling a divergent OB-fold, which would constitute the first occurrence of an OB-fold-like domain in a protein-primed genome.
Collapse
Affiliation(s)
- Ana Lechuga
- Centro de Biologiìa Molecular Severo Ochoa (CSIC-UAM), Madrid, Spain
| | - Darius Kazlauskas
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Saulėtekio Av. 7, Vilnius, Lithuania
| | - Margarita Salas
- Centro de Biologiìa Molecular Severo Ochoa (CSIC-UAM), Madrid, Spain
| | - Modesto Redrejo-Rodríguez
- Centro de Biologiìa Molecular Severo Ochoa (CSIC-UAM), Madrid, Spain
- Departamento de Bioquímica, Universidad Autónoma de Madrid (UAM), Madrid, Spain
- Instituto de Investigaciones Biomédicas Alberto Sols (CSIC-UAM), Madrid, Spain
| |
Collapse
|
6
|
Gillis A, Hock L, Mahillon J. Comparative Genomics of Prophages Sato and Sole Expands the Genetic Diversity Found in the Genus Betatectivirus. Microorganisms 2021; 9:1335. [PMID: 34205474 PMCID: PMC8234876 DOI: 10.3390/microorganisms9061335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 06/13/2021] [Accepted: 06/15/2021] [Indexed: 11/16/2022] Open
Abstract
Tectiviruses infecting the Bacillus cereus group represent part of the bacterial "plasmid repertoire" as they behave as linear plasmids during their lysogenic cycle. Several novel tectiviruses have been recently found infecting diverse strains belonging the B. cereus lineage. Here, we report and analyze the complete genome sequences of phages Sato and Sole. The linear dsDNA genome of Sato spans 14,852 bp with 32 coding DNA sequences (CDSs), whereas the one of Sole has 14,444 bp comprising 30 CDSs. Both phage genomes contain inverted terminal repeats and no tRNAs. Genomic comparisons and phylogenetic analyses placed these two phages within the genus Betatectivirus in the family Tectiviridae. Additional comparative genomic analyses indicated that the "gene regulation-genome replication" module of phages Sato and Sole is more diverse than previously observed among other fully sequenced betatectiviruses, displaying very low sequence similarities and containing some ORFans. Interestingly, the ssDNA binding protein encoded in this genomic module in phages Sato and Sole has very little amino acid similarity with those of reference betatectiviruses. Phylogenetic analyses showed that both Sato and Sole represent novel tectivirus species, thus we propose to include them as two novel species in the genus Betatectivirus.
Collapse
Affiliation(s)
- Annika Gillis
- Laboratory of Food and Environmental Microbiology, Earth and Life Institute, UCLouvain, Croix du Sud 2, L7.05.12, B-1348 Louvain-la-Neuve, Belgium;
| | | | - Jacques Mahillon
- Laboratory of Food and Environmental Microbiology, Earth and Life Institute, UCLouvain, Croix du Sud 2, L7.05.12, B-1348 Louvain-la-Neuve, Belgium;
| |
Collapse
|
7
|
Rapid Microscopic Detection of Bacillus anthracis by Fluorescent Receptor Binding Proteins of Bacteriophages. Microorganisms 2020; 8:microorganisms8060934. [PMID: 32575866 PMCID: PMC7356292 DOI: 10.3390/microorganisms8060934] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 06/18/2020] [Accepted: 06/19/2020] [Indexed: 12/19/2022] Open
Abstract
Bacillus anthracis, the etiological agent of anthrax disease, is typically diagnosed by immunological and molecular methods such as polymerase chain reaction (PCR). Alternatively, mass spectrometry techniques may aid in confirming the presence of the pathogen or its toxins. However, because of the close genetic relationship between B. anthracis and other members of the Bacillus cereus sensu lato group (such as Bacillus cereus or Bacillus thuringiensis) mis- or questionable identification occurs frequently. Also, bacteriophages such as phage gamma (which is highly specific for B. anthracis) have been in use for anthrax diagnostics for many decades. Here we employed host cell-specific receptor binding proteins (RBP) of (pro)-phages, also known as tail or head fibers, to develop a microscopy-based approach for the facile, rapid and unambiguous detection of B. anthracis cells. For this, the genes of (putative) RBP from Bacillus phages gamma, Wip1, AP50c and from lambdoid prophage 03 located on the chromosome of B. anthracis were selected. Respective phage genes were heterologously expressed in Escherichia coli and purified as fusions with fluorescent proteins. B. anthracis cells incubated with either of the reporter fusion proteins were successfully surface-labeled. Binding specificity was confirmed as RBP fusion proteins did not bind to most isolates of a panel of other B. cereus s.l. species or to more distantly related bacteria. Remarkably, RBP fusions detected encapsulated B. anthracis cells, thus RBP were able to penetrate the poly-γ-d-glutamate capsule of B. anthracis. From these results we anticipate this RBP-reporter assay may be useful for rapid confirmative identification of B. anthracis.
Collapse
|
8
|
Boon M, De Zitter E, De Smet J, Wagemans J, Voet M, Pennemann FL, Schalck T, Kuznedelov K, Severinov K, Van Meervelt L, De Maeyer M, Lavigne R. 'Drc', a structurally novel ssDNA-binding transcription regulator of N4-related bacterial viruses. Nucleic Acids Res 2020; 48:445-459. [PMID: 31724707 PMCID: PMC7145618 DOI: 10.1093/nar/gkz1048] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 10/16/2019] [Accepted: 10/23/2019] [Indexed: 12/22/2022] Open
Abstract
Bacterial viruses encode a vast number of ORFan genes that lack similarity to any other known proteins. Here, we present a 2.20 Å crystal structure of N4-related Pseudomonas virus LUZ7 ORFan gp14, and elucidate its function. We demonstrate that gp14, termed here as Drc (ssDNA-binding RNA Polymerase Cofactor), preferentially binds single-stranded DNA, yet contains a structural fold distinct from other ssDNA-binding proteins (SSBs). By comparison with other SSB folds and creation of truncation and amino acid substitution mutants, we provide the first evidence for the binding mechanism of this unique fold. From a biological perspective, Drc interacts with the phage-encoded RNA Polymerase complex (RNAPII), implying a functional role as an SSB required for the transition from early to middle gene transcription during phage infection. Similar to the coliphage N4 gp2 protein, Drc likely binds locally unwound middle promoters and recruits the phage RNA polymerase. However, unlike gp2, Drc does not seem to need an additional cofactor for promoter melting. A comparison among N4-related phage genera highlights the evolutionary diversity of SSB proteins in an otherwise conserved transcription regulation mechanism.
Collapse
Affiliation(s)
- Maarten Boon
- Department of Biosystems, Laboratory of Gene Technology, KU Leuven, Leuven 3001, Belgium
| | - Elke De Zitter
- Department of Chemistry, Biomolecular Architecture, KU Leuven, Leuven 3001, Belgium
| | - Jeroen De Smet
- Department of Biosystems, Laboratory of Gene Technology, KU Leuven, Leuven 3001, Belgium
| | - Jeroen Wagemans
- Department of Biosystems, Laboratory of Gene Technology, KU Leuven, Leuven 3001, Belgium
| | - Marleen Voet
- Department of Biosystems, Laboratory of Gene Technology, KU Leuven, Leuven 3001, Belgium
| | - Friederike L Pennemann
- Department of Biosystems, Laboratory of Gene Technology, KU Leuven, Leuven 3001, Belgium
| | - Thomas Schalck
- Department of Biosystems, Laboratory of Gene Technology, KU Leuven, Leuven 3001, Belgium
| | | | | | - Luc Van Meervelt
- Department of Chemistry, Biomolecular Architecture, KU Leuven, Leuven 3001, Belgium
| | - Marc De Maeyer
- Department of Chemistry, Laboratory of Biomolecular Modelling and Design, KU Leuven, Leuven 3001, Belgium
| | - Rob Lavigne
- Department of Biosystems, Laboratory of Gene Technology, KU Leuven, Leuven 3001, Belgium
| |
Collapse
|
9
|
Fornelos N, Browning DF, Pavlin A, Podlesek Z, Hodnik V, Salas M, Butala M. Lytic gene expression in the temperate bacteriophage GIL01 is activated by a phage-encoded LexA homologue. Nucleic Acids Res 2019; 46:9432-9443. [PMID: 30053203 PMCID: PMC6182141 DOI: 10.1093/nar/gky646] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 07/13/2018] [Indexed: 12/14/2022] Open
Abstract
The GIL01 bacteriophage is a temperate phage that infects the insect pathogen Bacillus thuringiensis. During the lytic cycle, phage gene transcription is initiated from three promoters: P1 and P2, which control the expression of the early phage genes involved in genome replication and P3, which controls the expression of the late genes responsible for virion maturation and host lysis. Unlike most temperate phages, GIL01 lysogeny is not maintained by a dedicated phage repressor but rather by the host's regulator of the SOS response, LexA. Previously we showed that the lytic cycle was induced by DNA damage and that LexA, in conjunction with phage-encoded protein gp7, repressed P1. Here we examine the lytic/lysogenic switch in more detail and show that P3 is also repressed by a LexA-gp7 complex, binding to tandem LexA boxes within the promoter. We also demonstrate that expression from P3 is considerably delayed after DNA damage, requiring the phage-encoded DNA binding protein, gp6. Surprisingly, gp6 is homologous to LexA itself and, thus, is a rare example of a LexA homologue directly activating transcription. We propose that the interplay between these two LexA family members, with opposing functions, ensures the timely expression of GIL01 phage late genes.
Collapse
Affiliation(s)
- Nadine Fornelos
- Instituto de Biología Molecular 'Eladio Viñuela' (CSIC), Centro de Biología Molecular 'Severo Ochoa' (CSIC-Universidad Autónoma de Madrid), Cantoblanco, 28049 Madrid, Spain
| | - Douglas F Browning
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Anja Pavlin
- Department of Biology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Zdravko Podlesek
- Department of Biology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Vesna Hodnik
- Department of Biology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
| | - Margarita Salas
- Instituto de Biología Molecular 'Eladio Viñuela' (CSIC), Centro de Biología Molecular 'Severo Ochoa' (CSIC-Universidad Autónoma de Madrid), Cantoblanco, 28049 Madrid, Spain
| | - Matej Butala
- Department of Biology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia
| |
Collapse
|
10
|
Legendre M, Alempic JM, Philippe N, Lartigue A, Jeudy S, Poirot O, Ta NT, Nin S, Couté Y, Abergel C, Claverie JM. Pandoravirus Celtis Illustrates the Microevolution Processes at Work in the Giant Pandoraviridae Genomes. Front Microbiol 2019; 10:430. [PMID: 30906288 PMCID: PMC6418002 DOI: 10.3389/fmicb.2019.00430] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 02/19/2019] [Indexed: 12/22/2022] Open
Abstract
With genomes of up to 2.7 Mb propagated in μm-long oblong particles and initially predicted to encode more than 2000 proteins, members of the Pandoraviridae family display the most extreme features of the known viral world. The mere existence of such giant viruses raises fundamental questions about their origin and the processes governing their evolution. A previous analysis of six newly available isolates, independently confirmed by a study including three others, established that the Pandoraviridae pan-genome is open, meaning that each new strain exhibits protein-coding genes not previously identified in other family members. With an average increment of about 60 proteins, the gene repertoire shows no sign of reaching a limit and remains largely coding for proteins without recognizable homologs in other viruses or cells (ORFans). To explain these results, we proposed that most new protein-coding genes were created de novo, from pre-existing non-coding regions of the G+C rich pandoravirus genomes. The comparison of the gene content of a new isolate, pandoravirus celtis, closely related (96% identical genome) to the previously described p. quercus is now used to test this hypothesis by studying genomic changes in a microevolution range. Our results confirm that the differences between these two similar gene contents mostly consist of protein-coding genes without known homologs, with statistical signatures close to that of intergenic regions. These newborn proteins are under slight negative selection, perhaps to maintain stable folds and prevent protein aggregation pending the eventual emergence of fitness-increasing functions. Our study also unraveled several insertion events mediated by a transposase of the hAT family, 3 copies of which are found in p. celtis and are presumably active. Members of the Pandoraviridae are presently the first viruses known to encode this type of transposase.
Collapse
Affiliation(s)
- Matthieu Legendre
- Aix Marseille Univ, CNRS, IGS, Structural and Genomic Information Laboratory (UMR7256), Mediterranean Institute of Microbiology (FR3479), Marseille, France
| | - Jean-Marie Alempic
- Aix Marseille Univ, CNRS, IGS, Structural and Genomic Information Laboratory (UMR7256), Mediterranean Institute of Microbiology (FR3479), Marseille, France
| | - Nadège Philippe
- Aix Marseille Univ, CNRS, IGS, Structural and Genomic Information Laboratory (UMR7256), Mediterranean Institute of Microbiology (FR3479), Marseille, France
| | - Audrey Lartigue
- Aix Marseille Univ, CNRS, IGS, Structural and Genomic Information Laboratory (UMR7256), Mediterranean Institute of Microbiology (FR3479), Marseille, France
| | - Sandra Jeudy
- Aix Marseille Univ, CNRS, IGS, Structural and Genomic Information Laboratory (UMR7256), Mediterranean Institute of Microbiology (FR3479), Marseille, France
| | - Olivier Poirot
- Aix Marseille Univ, CNRS, IGS, Structural and Genomic Information Laboratory (UMR7256), Mediterranean Institute of Microbiology (FR3479), Marseille, France
| | - Ngan Thi Ta
- Aix Marseille Univ, CNRS, IGS, Structural and Genomic Information Laboratory (UMR7256), Mediterranean Institute of Microbiology (FR3479), Marseille, France
| | - Sébastien Nin
- Aix Marseille Univ, CNRS, IGS, Structural and Genomic Information Laboratory (UMR7256), Mediterranean Institute of Microbiology (FR3479), Marseille, France
| | - Yohann Couté
- Inserm, BIG-BGE, CEA, Université Grenoble Alpes, Grenoble, France
| | - Chantal Abergel
- Aix Marseille Univ, CNRS, IGS, Structural and Genomic Information Laboratory (UMR7256), Mediterranean Institute of Microbiology (FR3479), Marseille, France
| | - Jean-Michel Claverie
- Aix Marseille Univ, CNRS, IGS, Structural and Genomic Information Laboratory (UMR7256), Mediterranean Institute of Microbiology (FR3479), Marseille, France
| |
Collapse
|
11
|
Gillis A, Fayad N, Makart L, Bolotin A, Sorokin A, Kallassy M, Mahillon J. Role of plasmid plasticity and mobile genetic elements in the entomopathogen Bacillus thuringiensis serovar israelensis. FEMS Microbiol Rev 2018; 42:829-856. [PMID: 30203090 PMCID: PMC6199540 DOI: 10.1093/femsre/fuy034] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Accepted: 09/06/2018] [Indexed: 12/14/2022] Open
Abstract
Bacillus thuringiensis is a well-known biopesticide that has been used for more than 80 years. This spore-forming bacterium belongs to the group of Bacillus cereus that also includes, among others, emetic and diarrheic pathotypes of B. cereus, the animal pathogen Bacillus anthracis and the psychrotolerant Bacillus weihenstephanensis. Bacillus thuringiensis is rather unique since it has adapted its lifestyle as an efficient pathogen of specific insect larvae. One of the peculiarities of B. thuringiensis strains is the extent of their extrachromosomal pool, with strains harbouring more than 10 distinct plasmid molecules. Among the numerous serovars of B. thuringiensis, 'israelensis' is certainly emblematic since its host spectrum is apparently restricted to dipteran insects like mosquitoes and black flies, vectors of human and animal diseases such as malaria, yellow fever, or river blindness. In this review, the putative role of the mobile gene pool of B. thuringiensis serovar israelensis in its pathogenicity and dedicated lifestyle is reviewed, with specific emphasis on the nature, diversity, and potential mobility of its constituents. Variations among the few related strains of B. thuringiensis serovar israelensis will also be reported and discussed in the scope of this specialised insect pathogen, whose lifestyle in the environment remains largely unknown.
Collapse
Affiliation(s)
- Annika Gillis
- Laboratory of Food and Environmental Microbiology, Université catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium
| | - Nancy Fayad
- Laboratory of Food and Environmental Microbiology, Université catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium
- Laboratory of Biodiversity and Functional Genomics (BGF), Faculty of Sciences, Université Saint-Joseph, 1107 2050 Beirut, Lebanon
| | - Lionel Makart
- Laboratory of Food and Environmental Microbiology, Université catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium
| | - Alexander Bolotin
- UMR1319 Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, F-78350 Jouy-en-Josas, France
| | - Alexei Sorokin
- UMR1319 Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, F-78350 Jouy-en-Josas, France
| | - Mireille Kallassy
- Laboratory of Biodiversity and Functional Genomics (BGF), Faculty of Sciences, Université Saint-Joseph, 1107 2050 Beirut, Lebanon
| | - Jacques Mahillon
- Laboratory of Food and Environmental Microbiology, Université catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium
| |
Collapse
|
12
|
A novel, easy and rapid method for constructing yeast two-hybrid vectors using In-Fusion technology. Biotechniques 2018; 64:219-224. [PMID: 29673256 DOI: 10.2144/btn-2018-0007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Yeast two-hybrid systems are powerful tools for analyzing interactions between proteins. Vector construction is an essential step in yeast two-hybrid experiments, which require bait and prey plasmids. In this study, we modified the multiple cloning site sequence of the yeast plasmid pGADT7 by site-directed mutagenesis PCR to generate the pGADT7-In vector, which resulted in an easy and rapid method for constructing yeast two-hybrid vectors using the In-Fusion cloning technique. This method has three key advantages: only one pair of primers and one round of PCR are needed to generate bait and prey plasmids for each gene, it is restriction endonuclease- and ligase-independent, and it is fast and easily performed.
Collapse
|
13
|
Yutin N, Bäckström D, Ettema TJG, Krupovic M, Koonin EV. Vast diversity of prokaryotic virus genomes encoding double jelly-roll major capsid proteins uncovered by genomic and metagenomic sequence analysis. Virol J 2018; 15:67. [PMID: 29636073 PMCID: PMC5894146 DOI: 10.1186/s12985-018-0974-y] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 03/28/2018] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Analysis of metagenomic sequences has become the principal approach for the study of the diversity of viruses. Many recent, extensive metagenomic studies on several classes of viruses have dramatically expanded the visible part of the virosphere, showing that previously undetected viruses, or those that have been considered rare, actually are important components of the global virome. RESULTS We investigated the provenance of viruses related to tail-less bacteriophages of the family Tectiviridae by searching genomic and metagenomics sequence databases for distant homologs of the tectivirus-like Double Jelly-Roll major capsid proteins (DJR MCP). These searches resulted in the identification of numerous genomes of virus-like elements that are similar in size to tectiviruses (10-15 kilobases) and have diverse gene compositions. By comparison of the gene repertoires, the DJR MCP-encoding genomes were classified into 6 distinct groups that can be predicted to differ in reproduction strategies and host ranges. Only the DJR MCP gene that is present by design is shared by all these genomes, and most also encode a predicted DNA-packaging ATPase; the rest of the genes are present only in subgroups of this unexpectedly diverse collection of DJR MCP-encoding genomes. Only a minority encode a DNA polymerase which is a hallmark of the family Tectiviridae and the putative family "Autolykiviridae". Notably, one of the identified putative DJR MCP viruses encodes a homolog of Cas1 endonuclease, the integrase involved in CRISPR-Cas adaptation and integration of transposon-like elements called casposons. This is the first detected occurrence of Cas1 in a virus. Many of the identified elements are individual contigs flanked by inverted or direct repeats and appear to represent complete, extrachromosomal viral genomes, whereas others are flanked by bacterial genes and thus can be considered as proviruses. These contigs come from metagenomes of widely different environments, some dominated by archaea and others by bacteria, suggesting that collectively, the DJR MCP-encoding elements have a broad host range among prokaryotes. CONCLUSIONS The findings reported here greatly expand the known host range of (putative) viruses of bacteria and archaea that encode a DJR MCP. They also demonstrate the extreme diversity of genome architectures in these viruses that encode no universal proteins other than the capsid protein that was used as the marker for their identification. From a supposedly minor group of bacterial and archaeal viruses, these viruses are emerging as a substantial component of the prokaryotic virome.
Collapse
Affiliation(s)
- Natalya Yutin
- National Center for Biotechnology Information, National Library of Medicine. National Institutes of Health, Bethesda, MD, 20894, USA
| | - Disa Bäckström
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Box 596, -75123, Uppsala, SE, Sweden
| | - Thijs J G Ettema
- Department of Cell and Molecular Biology, Science for Life Laboratory, Uppsala University, Box 596, -75123, Uppsala, SE, Sweden
| | - Mart Krupovic
- Unité Biologie Moléculaire du Gène chez les Extrêmophiles, Department of Microbiology, Institut Pasteur, Paris, France
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine. National Institutes of Health, Bethesda, MD, 20894, USA.
| |
Collapse
|
14
|
Extending the hosts of Tectiviridae into four additional genera of Gram-positive bacteria and more diverse Bacillus species. Virology 2018; 518:136-142. [PMID: 29481984 DOI: 10.1016/j.virol.2018.02.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 02/14/2018] [Accepted: 02/16/2018] [Indexed: 11/23/2022]
Abstract
Tectiviridae are composed of tailless bacteriophages with an icosahedral capsid and an inner membrane enclosing a double-stranded 15 kb linear DNA genome. Five of the seven previously studied Tectivirus isolates infect bacteria from Bacillus cereus sensu lato group (Betatectivirus), one distantly related member (PRD1) infect Enterobactericeae (Alpatectivirus) and one recently discovered virus infect Gluconobacter cerinus (Gammatectivirus). Here we expand the host spectrum of Betatectivirus elements to four additional genera (Streptococcus, Exiguobacterium, Clostridium and Brevibacillus) and to more distantly related Bacillus species (B. pumilus and B. flexus) by studying the genomes of fourteen novel tectiviral elements. Overall, the genomes show significant conservation in gene synteny and in modules responsible for genome replication and formation of the virion core (including DNA packaging). Notable variation exists in regions encoding host attachment and lysis along with the surrounding area of a site in which mutations are known to alter phage life cycle.
Collapse
|
15
|
Gill JJ, Wang B, Sestak E, Young R, Chu KH. Characterization of a Novel Tectivirus Phage Toil and Its Potential as an Agent for Biolipid Extraction. Sci Rep 2018; 8:1062. [PMID: 29348539 PMCID: PMC5773508 DOI: 10.1038/s41598-018-19455-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 12/28/2017] [Indexed: 12/12/2022] Open
Abstract
The oleaginous bacterium Rhodococcus opacus PD630 is metabolically diverse and can be cultivated on various renewable resources to serve as a sustainable triacylglycerol (TAG) feedstock for biodiesel production. Current methods for TAG extraction are costly, but infection of cultures by lytic bacteriophages (phages) may be a viable approach for achieving release of intracellular lipid from oleaginous bacteria such as R. opacus. This study reports the novel tectiviral phage Toil capable of releasing intracellular contents including a fluorescent protein marker and TAGs into the supernatant after phage infection of R. opacus PD631, a domesticated derivative of strain PD630. Phage Toil is placed in the Tectiviridae by its morphology, the presence of a lipid membrane, its genome architecture and the presence of terminal covalently-linked proteins. Toil is the first tectivirus capable of infecting a member of the Actinobacteria. Microscopy shows that infected cells do not undergo sudden lysis but instead maintain their original shape for several hours, with the cellular morphology gradually deteriorating. Approximately 30% of intracellular TAGs could be recovered from the culture supernatants of Toil-infected PD631 cells. Phage Toil has potential to be used as an agent in extraction of TAGs from oleaginous bacterium R. opacus. IMPORTANCE This study reported the first tectivirus (Phage Toil) capable of infecting a member of the Actinobacteria. In this study, we showed that Phage Toil can infect oleaginous bacterium Rhodococcus opacus to release intracellular contents such as a fluorescent protein marker and TAG lipid granules, which can serve as a starting material for biodiesel production. This study demonstrates a new method to extract TAGs by using this phage. Additionally, Phage Toil can be a new model phage to advance knowledge regarding phage infection mechanisms in Rhodococcus and other mycolic acid-containing bacteria such as Mycobacterium.
Collapse
Affiliation(s)
- Jason J Gill
- Department of Animal Science, Texas A&M University, College Station, TX, 77843, USA
- Center for Phage Technology, Texas A&M University, College Station, TX, 77843, USA
| | - Baixin Wang
- Zachry Department of Civil Engineering, Texas A&M University, College Station, TX, 77843, USA
| | - Emily Sestak
- Zachry Department of Civil Engineering, Texas A&M University, College Station, TX, 77843, USA
| | - Ryland Young
- Center for Phage Technology, Texas A&M University, College Station, TX, 77843, USA
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843, USA
| | - Kung-Hui Chu
- Zachry Department of Civil Engineering, Texas A&M University, College Station, TX, 77843, USA.
| |
Collapse
|
16
|
Philippe C, Krupovic M, Jaomanjaka F, Claisse O, Petrel M, le Marrec C. Bacteriophage GC1, a Novel Tectivirus Infecting Gluconobacter Cerinus, an Acetic Acid Bacterium Associated with Wine-Making. Viruses 2018; 10:v10010039. [PMID: 29337868 PMCID: PMC5795452 DOI: 10.3390/v10010039] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 01/05/2018] [Accepted: 01/12/2018] [Indexed: 12/22/2022] Open
Abstract
The Gluconobacter phage GC1 is a novel member of the Tectiviridae family isolated from a juice sample collected during dry white wine making. The bacteriophage infects Gluconobacter cerinus, an acetic acid bacterium which represents a spoilage microorganism during wine making, mainly because it is able to produce ethyl alcohol and transform it into acetic acid. Transmission electron microscopy revealed tail-less icosahedral particles with a diameter of ~78 nm. The linear double-stranded DNA genome of GC1 (16,523 base pairs) contains terminal inverted repeats and carries 36 open reading frames, only a handful of which could be functionally annotated. These encode for the key proteins involved in DNA replication (protein-primed family B DNA polymerase) as well as in virion structure and assembly (major capsid protein, genome packaging ATPase (adenosine triphosphatase) and several minor capsid proteins). GC1 is the first tectivirus infecting an alphaproteobacterial host and is thus far the only temperate tectivirus of gram-negative bacteria. Based on distinctive sequence and life-style features, we propose that GC1 represents a new genus within the Tectiviridae, which we tentatively named “Gammatectivirus”. Furthermore, GC1 helps to bridge the gap in the sequence space between alphatectiviruses and betatectiviruses.
Collapse
Affiliation(s)
- Cécile Philippe
- Institut des Sciences de la Vigne et du Vin (ISVV), University Bordeaux, Equipe d'Accueil 4577, Unité de Recherche Oenologie, 33882 Villenave d'Ornon, France.
| | - Mart Krupovic
- Department of Microbiology, Institut Pasteur, 75015 Paris, France.
| | - Fety Jaomanjaka
- Institut des Sciences de la Vigne et du Vin (ISVV), University Bordeaux, Equipe d'Accueil 4577, Unité de Recherche Oenologie, 33882 Villenave d'Ornon, France.
| | - Olivier Claisse
- Institut des Sciences de la Vigne et du Vin (ISVV), University Bordeaux, Equipe d'Accueil 4577, Unité de Recherche Oenologie, 33882 Villenave d'Ornon, France.
- Institut National de la Recherche Agronomique (INRA), ISVV, Unité Sous Contrat 1366 Oenologie, 33882 Villenave d'Ornon, France.
| | - Melina Petrel
- Bordeaux Imaging Center, University Bordeaux, Unité Mixte de Service 3420 CNRS-Unité de Service 4, Institut National de la Santé et de la Recherche Médicale, 33076 Bordeaux, France.
| | - Claire le Marrec
- Institut des Sciences de la Vigne et du Vin (ISVV), University Bordeaux, Equipe d'Accueil 4577, Unité de Recherche Oenologie, 33882 Villenave d'Ornon, France.
| |
Collapse
|
17
|
Lechuga A, Berjón-Otero M, Salas M, Redrejo-Rodríguez M. Analysis of Direct Interaction between Viral DNA-binding Proteins by Protein Pull-down Co-immunoprecipitation Assay. Bio Protoc 2018; 8:e2678. [PMID: 34179232 DOI: 10.21769/bioprotoc.2678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 12/18/2017] [Accepted: 12/20/2017] [Indexed: 11/02/2022] Open
Abstract
This protocol analyzes the direct interaction between two DNA-binding proteins by pull-down co-immunoprecipitation. One of the proteins is overexpressed in E. coli as HA-tagged recombinant protein and cell-free extracts are immunoprecipitated in HA-affinity resin. Cell extracts are treated with nuclease to degrade DNA and RNA, which rules out nucleic acid-mediated indirect interaction. Then, a second immunoprecipitation step is performed using the purified putative partner protein. Co-immunoprecipitated proteins can be detected either by Coomassie Blue staining and/or Western blotting (WB) if a specific antibody is available. Moreover, many DNA/RNA binding proteins are highly electropositive, which can hinder WB under standard conditions, as has been shown in histones and histone-like proteins. In this case, we show that the high isoelectric point of the putative partner results in a poor transfer. Tips to troubleshot WB transfer of highly electropositive DNA-binding proteins are provided.
Collapse
Affiliation(s)
- Ana Lechuga
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones científicas y Universidad Autónoma de Madrid, Madrid, Spain
| | - Mónica Berjón-Otero
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones científicas y Universidad Autónoma de Madrid, Madrid, Spain
| | - Margarita Salas
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones científicas y Universidad Autónoma de Madrid, Madrid, Spain
| | - Modesto Redrejo-Rodríguez
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones científicas y Universidad Autónoma de Madrid, Madrid, Spain
| |
Collapse
|