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1.
Nat Commun ; 10(1): 5442, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31784519

RESUMO

Genome modifications are central components of the continuous arms race between viruses and their hosts. The archaeosine base (G+), which was thought to be found only in archaeal tRNAs, was recently detected in genomic DNA of Enterobacteria phage 9g and was proposed to protect phage DNA from a wide variety of restriction enzymes. In this study, we identify three additional 2'-deoxy-7-deazaguanine modifications, which are all intermediates of the same pathway, in viruses: 2'-deoxy-7-amido-7-deazaguanine (dADG), 2'-deoxy-7-cyano-7-deazaguanine (dPreQ0) and 2'-deoxy-7- aminomethyl-7-deazaguanine (dPreQ1). We identify 180 phages or archaeal viruses that encode at least one of the enzymes of this pathway with an overrepresentation (60%) of viruses potentially infecting pathogenic microbial hosts. Genetic studies with the Escherichia phage CAjan show that DpdA is essential to insert the 7-deazaguanine base in phage genomic DNA and that 2'-deoxy-7-deazaguanine modifications protect phage DNA from host restriction enzymes.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31527037

RESUMO

Globally, more people die annually from tuberculosis than from any other single infectious agent. Unfortunately, there is no commercially-available vaccine that is sufficiently effective at preventing acquisition of pulmonary tuberculosis in adults. In this study, pre-exposure prophylactic pulmonary delivery of active aerosolized anti-tuberculosis bacteriophage D29 was evaluated as an option for protection against Mycobacterium tuberculosis infection. An average bacteriophage concentration of approximately 1 PFU/alveolus was achieved in the lungs of mice using a nose-only inhalation device optimized with a dose simulation technique and adapted for use with a vibrating mesh nebulizer. Within 30 minutes of bacteriophage delivery, the mice received either a low dose (∼50-100 CFU), or an ultra-low dose (∼5-10 CFU), of M. tuberculosis H37Rv aerosol to the lungs. A prophylactic effect was observed with bacteriophage aerosol pre-treatment significantly decreasing M. tuberculosis burden in mouse lungs 24 hours and 3 weeks post-challenge (p < 0.05). These novel results indicate that a sufficient dose of nebulized mycobacteriophage aerosol to the lungs may be a valuable intervention to provide extra protection to health care professionals and other individuals at risk of exposure to M. tuberculosis.

3.
MBio ; 10(3)2019 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-31164468

RESUMO

Temperate phages encode an immunity system to control lytic gene expression during lysogeny. This gene regulatory circuit consists of multiple interacting genetic elements, and although it is essential for controlling phage growth, it is subject to conflicting evolutionary pressures. During superinfection of a lysogen, the prophage's circuit interacts with the superinfecting phage's circuit and prevents lytic growth if the two circuits are closely related. The circuitry is advantageous since it provides the prophage with a defense mechanism, but the circuitry is also disadvantageous since it limits the phage's host range during superinfection. Evolutionarily related phages have divergent, orthogonal immunity systems that no longer interact and are heteroimmune, but we do not understand how immunity systems evolve new specificities. Here, we use a group of Cluster A mycobacteriophages that exhibit a spectrum of genetic diversity to examine how immunity system evolution impacts superinfection immunity. We show that phages with mesotypic (i.e., genetically related but distinct) immunity systems exhibit asymmetric and incomplete superinfection phenotypes. They form complex immunity networks instead of well-defined immunity groups, and mutations conferring escape (i.e., virulence) from homotypic or mesotypic immunity have various escape specificities. Thus, virulence and the evolution of new immune specificities are shaped by interactions with homotypic and mesotypic immunity systems.IMPORTANCE Many aspects regarding superinfection, immunity, virulence, and the evolution of immune specificities are poorly understood due to the lack of large collections of isolated and sequenced phages with a spectrum of genetic diversity. Using a genetically diverse collection of Cluster A phages, we show that the classical and relatively straightforward patterns of homoimmunity, heteroimmunity, and virulence result from interactions between homotypic and heterotypic phages at the extreme edges of an evolutionary continuum of immune specificities. Genetic interactions between mesotypic phages result in more complex mesoimmunity phenotypes and virulence profiles. These results highlight that the evolution of immune specificities can be shaped by homotypic and mesotypic interactions and may be more dynamic than previously considered.

4.
Nat Med ; 25(5): 730-733, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31068712

RESUMO

A 15-year-old patient with cystic fibrosis with a disseminated Mycobacterium abscessus infection was treated with a three-phage cocktail following bilateral lung transplantation. Effective lytic phage derivatives that efficiently kill the infectious M. abscessus strain were developed by genome engineering and forward genetics. Intravenous phage treatment was well tolerated and associated with objective clinical improvement, including sternal wound closure, improved liver function, and substantial resolution of infected skin nodules.


Assuntos
Infecções por Micobactéria não Tuberculosa/terapia , Mycobacterium abscessus , Terapia por Fagos/métodos , Adolescente , Fibrose Cística/microbiologia , Farmacorresistência Bacteriana , Feminino , Engenharia Genética/métodos , Humanos , Infecções por Micobactéria não Tuberculosa/microbiologia , Mycobacterium abscessus/efeitos dos fármacos
5.
BMC Genomics ; 20(1): 357, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31072320

RESUMO

BACKGROUND: Bacteriophages are the most abundant and diverse entities in the biosphere, and this diversity is driven by constant predator-prey evolutionary dynamics and horizontal gene transfer. Phage genome sequences are under-sampled and therefore present an untapped and uncharacterized source of genetic diversity, typically characterized by highly mosaic genomes and no universal genes. To better understand the diversity and relationships among phages infecting human pathogens, we have analysed the complete genome sequences of 205 phages of Staphylococcus sp. RESULTS: These are predicted to encode 20,579 proteins, which can be sorted into 2139 phamilies (phams) of related sequences; 745 of these are orphams and possess only a single gene. Based on shared gene content, these phages were grouped into four clusters (A, B, C and D), 27 subclusters (A1-A2, B1-B17, C1-C6 and D1-D2) and one singleton. However, the genomes have mosaic architectures and individual genes with common ancestors are positioned in distinct genomic contexts in different clusters. The staphylococcal Cluster B siphoviridae are predicted to be temperate, and the integration cassettes are often closely-linked to genes implicated in bacterial virulence determinants. There are four unusual endolysin organization strategies found in Staphylococcus phage genomes, with endolysins predicted to be encoded as single genes, two genes spliced, two genes adjacent and as a single gene with inter-lytic-domain secondary translational start site. Comparison of the endolysins reveals multi-domain modularity, with conservation of the SH3 cell wall binding domain. CONCLUSIONS: This study provides a high-resolution view of staphylococcal viral genetic diversity, and insights into their gene flux patterns within and across different phage groups (cluster and subclusters) providing insights into their evolution.


Assuntos
Evolução Molecular , Variação Genética , Genoma Viral , Genômica/métodos , Fagos de Staphylococcus/classificação , Fagos de Staphylococcus/genética , Proteínas Virais/genética , Mapeamento Cromossômico , Humanos , Filogenia
6.
Tuberculosis (Edinb) ; 115: 14-23, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30948168

RESUMO

A collection of over 1600 sequenced bacteriophages isolated on a single host strain, Mycobacterium smegmatis mc2155, can be grouped into over two dozen types that have little or no nucleotide sequence similarity to each other. One group, Cluster K, can be divided into several subclusters, and the well-characterized and much exploited phage TM4 lies in Subcluster K2. Many of the Cluster K phages have broad host ranges and infect both fast- and slow-growing mycobacterial strains. Here we describe phage ZoeJ, a new Subcluster K2 member, which infects a broad spectrum of mycobacterial hosts including M. smegmatis, Mycobacterium tuberculosis, and Mycobacterium avium. ZoeJ has extensive sequence similarity to TM4, and comparative analysis reveals the precise deletion conferring the lytic phenotype of TM4. The ZoeJ immunity repressor was identified as gene 45, which is prophage-expressed, is required for lysogeny, and is sufficient to confer superinfection immunity to ZoeJ. ZoeJ gp45 also confers immunity to Subcluster K2 phage Milly, and Subcluster K1 phages Adephagia and CrimD, but surprisingly not to TM4. RNAseq analysis reveals the temporal pattern of early and late gene expressions in ZoeJ lytic growth and suggests a role for the ESAS motifs for gene regulation.

7.
MBio ; 10(2)2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30890601

RESUMO

Temperate phages play important roles in the physiology of their bacterial hosts and establish a lysogenic relationship with the host through which prophage-expressed genes confer new phenotypes. A key phenotype is prophage-mediated defense against heterotypic viral attack, in which temperate phages collude with their bacterial host to prevent other phages from attacking, sometimes with exquisite specificity. Such defense systems have been described in Pseudomonas and Mycobacterium phages but are likely widespread throughout the microbial community. Here, we describe a novel prophage-mediated defense system encoded by Gordonia phage CarolAnn, which defends against infection by unrelated phages grouped in cluster CZ. CarolAnn genes 43 and 44 are coexpressed with the repressor and are necessary and sufficient to confer defense against phage Kita and its close relatives. Kita and these relatives are targeted through Kita gene 53, a gene that is of unknown function but which is the location of defense escape mutations that overcome CarolAnn defense. Expression of Kita gene 53 is toxic to Gordonia terrae in the presence of CarolAnn genes 43 and 44, suggesting that defense may be mediated by an abortive infection type of mechanism. CarolAnn genes 43 and 44 are distant relatives of mycobacteriophage Sbash genes 31 and 30, respectively, which also confer viral defense but use a different targeting system.IMPORTANCE Prophage-mediated viral defense systems play a key role in microbial dynamics, as lysogeny is established relatively efficiently, and prophage-expressed genes can strongly inhibit lytic infection of other, unrelated phages. Demonstrating such defense systems in Gordonia terrae suggests that these systems are widespread and that there are a multitude of different systems with different specificities for the attacking phages.


Assuntos
Bacteriófagos/fisiologia , Gordonia (Bactéria)/fisiologia , Gordonia (Bactéria)/virologia , Interações Hospedeiro-Parasita , Lisogenia , Prófagos/fisiologia
8.
MBio ; 10(2)2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30890613

RESUMO

The arms race between bacteria and their bacteriophages profoundly influences microbial evolution. With an estimated 1023 phage infections occurring per second, there is strong selection for both bacterial survival and phage coevolution for continued propagation. Many phage resistance systems, including restriction-modification systems, clustered regularly interspaced short palindromic repeat-Cas (CRISPR-Cas) systems, a variety of abortive infection systems, and many others that are not yet mechanistically defined, have been described. Temperate bacteriophages are common and form stable lysogens that are immune to superinfection by the same or closely related phages. However, temperate phages collude with their hosts to confer defense against genomically distinct phages, to the mutual benefit of the bacterial host and the prophage. Prophage-mediated viral systems have been described in Mycobacterium phages and Pseudomonas phages but are predicted to be widespread throughout the microbial world. Here we describe a new viral defense system in which the mycobacteriophage Sbash prophage colludes with its Mycobacterium smegmatis host to confer highly specific defense against infection by the unrelated mycobacteriophage Crossroads. Sbash genes 30 and 31 are lysogenically expressed and are necessary and sufficient to confer defense against Crossroads but do not defend against any of the closely related phages grouped in subcluster L2. The mapping of Crossroads defense escape mutants shows that genes 132 and 141 are involved in recognition by the Sbash defense system and are proposed to activate a loss in membrane potential mediated by Sbash gp30 and gp31.IMPORTANCE Viral infection is an ongoing challenge to bacterial survival, and there is strong selection for development or acquisition of defense systems that promote survival when bacteria are attacked by bacteriophages. Temperate phages play central roles in these dynamics through lysogenic expression of genes that defend against phage attack, including those unrelated to the prophage. Few prophage-mediated viral defense systems have been characterized, but they are likely widespread both in phage genomes and in the prophages integrated in bacterial chromosomes.


Assuntos
Interações Hospedeiro-Parasita , Micobacteriófagos/fisiologia , Mycobacterium smegmatis/fisiologia , Mycobacterium smegmatis/virologia , Lisogenia , Prófagos/fisiologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-30714032

RESUMO

We report the complete annotated genome sequence of Microbacterium foliorum NRRL B-24224, a type strain isolated from the phyllosphere of grasses and a commonly used host for bacteriophage discovery. The genome contains no identifiable prophage or CRISPR or restriction-modification system, which suggests that it may continue to be a fruitful host for phage discovery.

10.
Artigo em Inglês | MEDLINE | ID: mdl-30637400

RESUMO

Bacteriophages Balsa, Golden, and Lucky3 are cluster EA phages isolated from flowers and infect Microbacterium foliorum NRRL B-24224. The genomes of Golden and Lucky3 (subcluster EA1) are closely related, whereas Balsa (subcluster EA4) is a more distant relative.

11.
Methods Mol Biol ; 1898: 27-36, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30570720

RESUMO

Fluoromycobacteriophages are a new class of reporter phages that contain Laboratorio fluorescent reporter genes (gfp, ZsYellow, and mCherry) and provide a simple means of revealing the metabolic state of mycobacterial cells and therefore their response to antibiotics. Here we described a simple and rapid method for drug susceptibility testing (DST) of Mycobacterium spp using a fluorescence microscope, a flow cytometer, or a fluorimeter in a convenient multiwell format.


Assuntos
Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana/métodos , Micobacteriófagos/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Proteínas de Fluorescência Verde/genética , Humanos , Microscopia de Fluorescência , Micobacteriófagos/genética , Mycobacterium tuberculosis/patogenicidade , Mycobacterium tuberculosis/virologia
12.
Methods Mol Biol ; 1898: 69-80, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30570724

RESUMO

We describe a recombineering-based method for the genetic manipulation of lytically replicating bacteriophages, focusing on mycobacteriophages. The approach utilizes recombineering-proficient strains of Mycobacterium smegmatis and employs a cotransformation strategy with purified phage genomic DNA and a mutagenic substrate, which selects for only those cells that are competent to take up DNA. The cotransformation method, combined with the high rates of recombination obtained in M. smegmatis recombineering strains, allows for the efficient and rapid generation of bacteriophage mutants.


Assuntos
Bacteriófagos/genética , DNA/genética , Mycobacterium smegmatis/genética , Recombinação Genética , Bacteriófagos/química , DNA/química , Eletroquimioterapia , Eletroporação , Engenharia Genética , Mutagênese/genética , Mycobacterium smegmatis/virologia
13.
Viruses ; 10(11)2018 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-30423804

RESUMO

Modern agriculture is expected to face an increasing global demand for food while also needing to comply with higher sustainability standards. Therefore, control of crop pathogens requires new, green alternatives to current methods. Potatoes are susceptible to several bacterial diseases, with infections by soft rot Enterobacteriaceae (SRE) being a significant contributor to the major annual losses. As there are currently no efficient ways of combating SRE, we sought to develop an approach that could easily be incorporated into the potato production pipeline. To this end, 46 phages infecting the emerging potato pathogen Dickeya solani were isolated and thoroughly characterized. The 46 isolated phages were grouped into three different groups based on DNA similarity, representing two distinct clusters and a singleton. One cluster showed similarity to phages previously used to successfully treat soft rot in potatoes, whereas the remaining phages were novel and showed only very limited similarity to previously isolated phages. We selected six diverse phages in order to create the hereto most complex phage cocktail against SRE. The cocktail was applied in a proof-of-principle experiment to treat soft rot in potatoes under simulated storage conditions. We show that the phage cocktail was able to significantly reduce the incidence of soft rot as well as disease severity after 5 days of storage post-infection with Dickeya solani. This confirms results from previous studies that phages represent promising biocontrol agents against SRE infection in potato.


Assuntos
Bacteriófagos/fisiologia , Enterobacteriaceae/virologia , Bacteriófagos/classificação , Biologia Computacional/métodos , Genoma Viral , Genômica/métodos , Anotação de Sequência Molecular , Terapia por Fagos , Doenças das Plantas/microbiologia , Doenças das Plantas/terapia , Solanum tuberosum/virologia
14.
Microbiol Spectr ; 6(5)2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30291704

RESUMO

Mycobacteriophages are viruses that infect mycobacterial hosts. A large number of mycobacteriophages have been isolated and genomically characterized, providing insights into viral diversity and evolution, as well as fueling development of tools for mycobacterial genetics. Mycobacteriophages have intimate relationships with their hosts and provide insights into the genetics and physiology of the mycobacteria and tools for potential clinical applications such as drug development, diagnosis, vaccines, and potentially therapy.


Assuntos
Mycobacteriaceae/virologia , Micobacteriófagos/fisiologia , DNA Viral/genética , Genoma Viral , Interações Hospedeiro-Patógeno , Humanos , Mycobacteriaceae/genética , Micobacteriófagos/genética , Micobacteriófagos/ultraestrutura , Terapia por Fagos
15.
Sci Rep ; 8(1): 12772, 2018 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-30143740

RESUMO

In the current report, we describe the identification of three genetically distinct groups of prophages integrated into three different chromosomal sites of human gut-associated Bifidobacterium breve and Bifidobacterium longum strains. These bifidobacterial prophages are distantly related to temperate actinobacteriophages of several hosts. Some prophages, integrated within the dnaJ2 gene, are competent for induction, excision, replication, assembly and lysis, suggesting that they are fully functional and can generate infectious particles, even though permissive hosts have not yet been identified. Interestingly, several of these phages harbor a putative phase variation shufflon (the Rin system) that generates variation of the tail-associated receptor binding protein (RBP). Unlike the analogous coliphage-associated shufflon Min, or simpler Cin and Gin inversion systems, Rin is predicted to use a tyrosine recombinase to promote inversion, the first reported phage-encoded tyrosine-family DNA invertase. The identification of bifidobacterial prophages with RBP diversification systems that are competent for assembly and lysis, yet fail to propagate lytically under laboratory conditions, suggests dynamic evolution of bifidobacteria and their phages in the human gut.


Assuntos
Bifidobacterium/virologia , Microbioma Gastrointestinal , Prófagos/fisiologia , Sítios de Ligação Microbiológicos/genética , Sequência de Bases , Bifidobacterium/efeitos dos fármacos , Evolução Biológica , Microbioma Gastrointestinal/efeitos dos fármacos , Genoma Viral , Especificidade de Hospedeiro/efeitos dos fármacos , Especificidade de Hospedeiro/genética , Humanos , Mitomicina/farmacologia , Prófagos/efeitos dos fármacos , Prófagos/genética , Prófagos/ultraestrutura , Vírion/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
16.
Front Microbiol ; 9: 1471, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30026735

RESUMO

The World Health Organization (WHO) estimates that 40% of tuberculosis (TB) cases are not diagnosed and treated correctly. Even though there are several diagnostic tests available in the market, rapid, easy, inexpensive detection, and drug susceptibility testing (DST) of Mycobacterium tuberculosis is still of critical importance specially in low and middle-income countries with high incidence of the disease. In this work, we have developed a microscopy-based methodology using the reporter mycobacteriophage mCherrybomb ϕ for detection of Mycobacterium spp. and phenotypic determination of rifampicin resistance within just days from sputum sample collection. Fluoromycobacteriophage methodology is compatible with regularly used protocols in clinical laboratories for TB diagnosis and paraformaldehyde fixation after infection reduces biohazard risks with sample analysis by fluorescence microscopy. We have also set up conditions for discrimination between M. tuberculosis complex (MTBC) and non-tuberculous mycobacteria (NTM) strains by addition of p-nitrobenzoic acid (PNB) during the assay. Using clinical isolates of pre-XDR and XDR-TB strains from this study, we tested mCherrybomb Φ for extended DST and we compared the antibiotic resistance profile with those predicted by whole genome sequencing. Our results emphasize the utility of a phenotypic test for M. tuberculosis extended DST. The many attributes of mCherrybomb Φ suggests this could be a useful component of clinical microbiological laboratories for TB diagnosis and since only viable cells are detected this could be a useful tool for monitoring patient response to treatment.

17.
Mol Microbiol ; 108(4): 443-460, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29488662

RESUMO

Bacteriophages engage in complex dynamic interactions with their bacterial hosts and with each other. Bacteria have numerous mechanisms to resist phage infection, and phages must co-evolve by overcoming bacterial resistance or by choosing an alternative host. Phages also compete with each other, both during lysogeny by prophage-mediated defense against viral attack and by superinfection exclusion during lytic replication. Phages are enormously diverse genetically and are replete with small genes of unknown function, many of which are not required for lytic growth, but which may modulate these bacteria-phage and phage-phage dynamics. Using cellular toxicity of phage gene overexpression as an assay, we identified the 93-residue protein gp52 encoded by Cluster F mycobacteriophage Fruitloop. The toxicity of Fruitloop gp52 overexpression results from interaction with and inactivation of Wag31 (DivIVA), an essential Mycobacterium smegmatis protein organizing cell wall biosynthesis at the growing cellular poles. Fruitloop gene 52 is expressed early in lytic growth and is not required for normal Fruitloop lytic replication but interferes with Subcluster B2 phages such as Hedgerow and Rosebush. We conclude that Hedgerow and Rosebush are Wag31-dependent phages and that Fruitloop gp52 confers heterotypic superinfection exclusion by inactivating Wag31.


Assuntos
Proteínas de Bactérias/metabolismo , Micobacteriófagos/fisiologia , Mycobacterium smegmatis/virologia , Proteínas do Envelope Viral/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Parede Celular/metabolismo , Lisogenia , Mutação , Micobacteriófagos/genética , Mycobacterium smegmatis/genética , Plasmídeos , Proteômica , Alinhamento de Sequência , Análise de Sequência de RNA , Proteínas do Envelope Viral/genética
18.
BMC Microbiol ; 18(1): 19, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29490612

RESUMO

BACKGROUND: A remarkable exception to the large genetic diversity often observed for bacteriophages infecting a specific bacterial host was found for the Cutibacterium acnes (formerly Propionibacterium acnes) phages, which are highly homogeneous. Phages infecting the related species, which is also a member of the Propionibacteriaceae family, Propionibacterium freudenreichii, a bacterium used in production of Swiss-type cheeses, have also been described and are common contaminants of the cheese manufacturing process. However, little is known about their genetic composition and diversity. RESULTS: We obtained seven independently isolated bacteriophages that infect P. freudenreichii from Swiss-type cheese samples, and determined their complete genome sequences. These data revealed that all seven phage isolates are of similar genomic length and GC% content, but their genomes are highly diverse, including genes encoding the capsid, tape measure, and tail proteins. In contrast to C. acnes phages, all P. freudenreichii phage genomes encode a putative integrase protein, suggesting they are capable of lysogenic growth. This is supported by the finding of related prophages in some P. freudenreichii strains. The seven phages could further be distinguished as belonging to two distinct genomic types, or 'clusters', based on nucleotide sequences, and host range analyses conducted on a collection of P. freudenreichii strains show a higher degree of host specificity than is observed for the C. acnes phages. CONCLUSIONS: Overall, our data demonstrate P. freudenreichii bacteriophages are distinct from C. acnes phages, as evidenced by their higher genetic diversity, potential for lysogenic growth, and more restricted host ranges. This suggests substantial differences in the evolution of these related species from the Propionibacteriaceae family and their phages, which is potentially related to their distinct environmental niches.


Assuntos
Bacteriófagos/classificação , Bacteriófagos/genética , Bacteriófagos/isolamento & purificação , Queijo/virologia , Genoma Viral , Filogenia , Propionibacterium acnes/virologia , Propionibacterium freudenreichii/virologia , Bacteriófagos/ultraestrutura , Composição de Bases , Sequência de Bases , Queijo/microbiologia , Mapeamento Cromossômico , Variação Genética , Genômica , Especificidade de Hospedeiro , Lisogenia , Anotação de Sequência Molecular , Prófagos/genética , Propionibacteriaceae/virologia , Propionibacterium/virologia , Sequenciamento Completo do Genoma
19.
J Bacteriol ; 200(9)2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29463602

RESUMO

Roger W. Hendrix was at the forefront of bacteriophage biology for nearly 50 years and was central to our understanding of both viral capsid assembly and phage genomic diversity and evolution. Roger's warm and gentle demeanor belied a razor-sharp mind and warmed him to numerous highly productive collaborations that amplified his scientific impact. Roger was always completely open with scientific ideas while at the same time quietly agitating with a stream of new ways of thinking about problems and nudging our communities to search for innovative solutions: a gentle but highly effective provocateur.


Assuntos
Bacteriófagos , Virologia/história , História do Século XX , História do Século XXI , Estados Unidos , Universidades
20.
Genome Announc ; 6(5)2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29437090

RESUMO

We report here the complete genome sequences of 44 phages infecting Arthrobacter sp. strain ATCC 21022. These phages have double-stranded DNA genomes with sizes ranging from 15,680 to 70,707 bp and G+C contents from 45.1% to 68.5%. All three tail types (belonging to the families Siphoviridae, Myoviridae, and Podoviridae) are represented.

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