The Experts below are selected from a list of 177 Experts worldwide ranked by ideXlab platform
Arvind Varsani - One of the best experts on this subject based on the ideXlab platform.
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Genome Sequence of a Single-Stranded DNA Virus Identified in Gila Monster Feces
Microbiology resource announcements, 2018Co-Authors: Vasishta Somayaji, Dale F. Denardo, Melissa A. Wilson Sayres, Mellecha Blake, Kara Waits, Rafaela S. Fontenele, Simona Kraberger, Arvind VarsaniAbstract:ABSTRACT The Gila monster (Heloderma suspectum) is native to the Sonoran Desert. Metagenomic analyses of a Gila monster fecal sample revealed the presence of a small, circular, Single-Stranded DNA Virus that is most closely related to a gemykrogVirus (family Genomoviridae) genome from caribou feces sharing 88% genome-wide pairwise identity.
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Discovery of Sclerotinia sclerotiorum Hypovirulence-Associated Virus-1 in Urban River Sediments of Heathcote and Styx Rivers in Christchurch City, New Zealand
Genome Announcements, 2013Co-Authors: Simona Kraberger, Daisy Stainton, Anisha Dayaram, Peyman Zawar-reza, Christopher Gomez, Jon S. Harding, Arvind VarsaniAbstract:ABSTRACT In samples of benthic and bank river sediments of two urban rivers in Christchurch city (New Zealand), we identified and recovered isolates of Sclerotinia sclerotiorum hypovirulence-associated Virus-1 (SsHADV-1), a fungus-infecting circular Single-Stranded DNA Virus. This is the first report of SsHADV-1 outside of China and in environmental samples.
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Discovery of a novel circular Single-Stranded DNA Virus from porcine faeces
Archives of Virology, 2012Co-Authors: Alyssa Sikorski, Anisha Dayaram, Gerardo R. Argüello-astorga, Renwick C. J. Dobson, Arvind VarsaniAbstract:A large number of novel Single-Stranded DNA (ssDNA) Viruses have been characterised from various environmental sources in the last 5 years. The bulk of these have been from faecal sources, and faecal sampling is an ideal non-invasive pathogen sampling method. We characterised a novel ssDNA from a porcine faecal sample from Cass Basin of the South Island of New Zealand. The novel viral genome has two large open reading frames (ORFs), which are bidirectionally transcribed and separated by intergenic regions. The largest ORF has some degree of similarity (
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Dragonfly cycloVirus, a novel Single-Stranded DNA Virus discovered in dragonflies (Odonata: Anisoptera)
Journal of General Virology, 2011Co-Authors: Karyna Rosario, Darren P. Martin, Simona Kraberger, Mya Breitbart, Daisy Stainton, Milen Marinov, Elizabeth J. Wiltshire, David A. Collings, Matthew Walters, Arvind VarsaniAbstract:Dragonfly cycloVirus (DfCyV), a new species of ssDNA Virus discovered using viral metagenomics in dragonflies (familyLibellulidae) from the Kingdom of Tonga. Metagenomic sequences of DfCyV were similar to Viruses of the recently proposed genus CycloVirus within the family Circoviridae. Specific PCRs resulted in the recovery of 21 DfCyV genomes from three dragonfly species (Pantala flavescens, Tholymis tillarga and Diplacodes bipunctata). The 1741 nt DfCyV genomes share >95 % nucleotide identity and are classified into 11 subtypes representing a single strain. The DfCyV genomes share 48–63 % genome-wide nucleotide identity with cycloViruses identified in human faecal samples. Recombination analysis revealed three recombinant DfCyV genomes, suggesting that recombination plays an important role in cycloVirus evolution. To our knowledge, this is the first report of a circular ssDNA Virus identified in insects, and the data may help elucidate evolutionary links among novel Circoviridae recently identified in animals and environmental samples.
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Eragrostis minor streak Virus: an Asian streak Virus in Africa
Archives of Virology, 2011Co-Authors: Darren P. Martin, Dionne N. Shepherd, Pierre Lefeuvre, Daphne Linderme, Arvind VarsaniAbstract:The genus MastreVirus of the Single-Stranded DNA Virus family Geminiviridae consists of four distinct Virus lineages that have been sampled in different parts of the Old World. These include the Panicoideae-infecting African streak Viruses (ten described species including the geographical outlier, Digitaria streak Virus [DSV] from Vanuatu) and Australian striate mosaic Viruses (three described species), the dicotyledonous-plant-infecting mastreViruses (seven described species), and the Eurasian Pooideae-infecting dwarf Viruses (three described species). Of all known mastreVirus species, Miscanthus streak Virus (MiSV), members of which are found in Japan, is the most divergent and is the only one that lies outside these four main lineages. Besides the full-genome sequences of three very closely related MiSV isolates, nothing is presently known about the diversity of what is potentially a fifth major lineage of mastreViruses. Here, we describe a new MiSV-like Virus isolated from the grass Eragrostis minor. Curiously, this Virus, which we have tentatively named Eragrostis minor streak Virus (EMSV), was discovered in Namibia, Southern Africa—almost as far from Japan as it is possible to get within the Old World. An Eragrostis minor plant displaying chlorotic discontinuous streaks running along the major leaf veins (i.e., streak symptoms characteristic of mastreVirus infections) was sampled in the Caprivi region (S18.06447; E21.83855) of Namibia in November 2009. Circular DNA molecules were amplified from a crude total DNA extract using Phi29 DNA polymerase (TempliPhi TM , GE Healthcare, USA) as
Yuji Tomaru - One of the best experts on this subject based on the ideXlab platform.
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Isolation and Characterization of a Single-Stranded DNA Virus Infecting the Marine Diatom Chaetoceros sp. Strain SS628-11 Isolated from Western JAPAN
PLOS ONE, 2013Co-Authors: Kei Kimura, Yuji TomaruAbstract:Diatoms are significant organisms for primary production in the earth's aquatic environment. Hence, their dynamics are an important focus area in current studies. Viruses are a great concern as potential factors of diatom mortality, along with other physical, chemical, and biological factors. We isolated and characterized a new diatom Virus (Csp07DNAV) that lyses the marine planktonic diatom Chaetoceros sp. strain SS628-11. This paper examines the physiological, morphological, and genomic characteristics of Csp07DNAV. The Virus was isolated from a surface water sample that was collected at Hiroshima Bay, Japan. It was icosahedral, had a diameter of 34 nm, and accumulated in the nuclei of host cells. Rod-shaped Virus particles also coexisted in the host nuclei. The latent period and burst size were estimated to be
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New Single-Stranded DNA Virus with a unique genomic structure that infects marine diatom Chaetoceros setoensis
Scientific Reports, 2013Co-Authors: Yuji Tomaru, Hidekazu Suzuki, Tamotsu Nagumo, Kensuke Toyoda, Kei Kimura, Yoshitake TakaoAbstract:Diatoms are among the most abundant organisms in nature; however, their relationships with Single-Stranded DNA (ssDNA) Viruses have not yet been defined in detail. We report the isolation and characterisation of a Virus (CsetDNAV) that lytically infects the bloom-forming diatom Chaetoceros setoensis. The virion is 33 nm in diameter and accumulates in the nucleus of its host. CsetDNAV harbours a covalently closed-circular ssDNA genome comprising 5836 nucleotides and eight different short-complementary fragments (67–145 nucleotides), which have not been reported in other diatom Viruses. Phylogenetic analysis based on the putative replicase-related protein showed that CsetDNAV was not included in the monophyly of the recently established genus BacillaDNAVirus. This discovery of CsetDNAV, which harbours a genome with a structure that is unique among known Viruses that infect diatoms, suggests that other such undiscovered Viruses possess diverse genomic architectures.
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Isolation and characterisation of a Single-Stranded DNA Virus infecting the marine planktonic diatom Chaetoceros tenuissimus
Aquatic Microbial Ecology, 2011Co-Authors: Yuji Tomaru, Yoko Shirai, Kensuke Toyoda, Keizo NagasakiAbstract:Diatoms are important components of the biological community and food web in the aquatic environment. Here, we report the characteristics of a Single-Stranded RNA (ssRNA) Virus (CtenRNAV01) that infects the marine diatom Chaetoceros tenuissimus Meunier (Bacillariophyceae). The ca. 31-nm Virus particle is icosahedral and lacks a tail. CtenRNAV01 forms crystalline arrays occupying most of the infected host’s cytoplasm. By growth experiments, the lytic cycle and the burst size were estimated to be
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Isolation and Characterization of a Single-Stranded DNA Virus Infecting Chaetoceros lorenzianus Grunow
Applied and Environmental Microbiology, 2011Co-Authors: Yuji Tomaru, Yoshitake Takao, Hidekazu Suzuki, Tamotsu Nagumo, Kanae Koike, Keizo NagasakiAbstract:Diatoms are one of the most significant primary producers in the ocean, and the importance of Viruses as a potential source of mortality for diatoms has recently been recognized. Thus far, eight different diatom Viruses infecting the genera Rhizosolenia and Chaetoceros have been isolated and characterized to different extents. We report the isolation of a novel diatom Virus (ClorDNAV), which causes the lysis of the bloom-forming species Chaetoceros lorenzianus, and show its physiological, morphological, and genomic characteristics. The free virion was estimated to be ∼34 nm in diameter. The arrangement of Virus particles appearing in cross-section was basically a random aggregation in the nucleus. Occasionally, distinctive formations such as a ring-like array composed of 9 or 10 spherical virions or a centipede-like array composed of rod-shaped particles were also observed. The latent period and the burst size were estimated to be
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Isolation and characterization of a new Single-Stranded DNA Virus infecting the cosmopolitan marine diatom Chaetoceros debilis
Aquatic Microbial Ecology, 2008Co-Authors: Yuji Tomaru, Hidekazu Suzuki, Tamotsu Nagumo, Yoko Shirai, Keizo NagasakiAbstract:The genus Chaetoceros (Bacillariophyceae) is the dominant diatom in the world's oceans. Various physical, chemical and biological factors affect depletion of diatom populations, for which the importance of Viruses as a potential mortality source has only recently been found. We isolated and characterized a new Chaetoceros-infecting Virus causing the lysis of the cosmopolitan species C. debilis Cleve. The Virus infectious for C. debilis was isolated from both water and sediment samples collected in western Japan. We show the physiologic, morphologic and genomic characteristics of one Virus clone among many isolates. We first described the C. debilis DNA Virus (CdebDNAV), a 30 nm icosahedral Virus accumulating in the cytoplasm of C. debilis. Host specificity of CdebDNAV is strain-specific and its infectivity is stably maintained through a wide temperature range (between 20 and -196°C). The latent period and the burst size were estimated to be 12 to 24 h and 55 infectious units per host cell, respectively. CdebDNAV harbors a Single-Stranded DNA (ssDNA) genome whose structure is unknown. Sequence comparisons showed that the partial sequence of CdebDNAV is highly similar (E value = 10 -56 ) to the putative replicase gene of the C. salsugineum nuclear inclusion Virus (CsNIV) that harbors a covalently closed circular, partially doublestranded ssDNA genome. This discovery of CdebDNAV may aid in further understanding the ecological dynamics of C. debilis population blooms in nature.
J. R. Kerr - One of the best experts on this subject based on the ideXlab platform.
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ParvoVirus B19 infection
European Journal of Clinical Microbiology and Infectious Diseases, 1996Co-Authors: J. R. KerrAbstract:Human parvoVirus B19, discovered in 1974, is a Single-Stranded DNA Virus which causes erythema infectiosum, arthralgia, aplastic crisis in patients with red cell defects, chronic anaemia in immunocompromised patients, and fetal hydrops. Seroprevalence in developed countries is 2–10% in children less than 5 years, 40–60% in adults more than 20 years, and 85% or more in those over 70 years. The Virus may be transmitted by the respiratory route and by transfusion of infected blood and blood products. After an incubation period of six to eight days, viraemia occurs, during which reticulocyte numbers fall dramatically resulting in a temporary drop in haemoglobin of 1 g/dl in a normal person. Clearance of viraemia is dependent on development of specific antibody to the B19 structural proteins, VP1 and VP2. The red cell receptor for the Virus is blood group P antigen. Diagnosis in immunocompetent persons depends on detection of specific IgM in serum. Diagnosis in immunocompromised persons depends on detection of B19 antigen or DNA in serum. There is no specific treatment for B19 infection; however, human normal immunoglobulin may be used as a source of specific antibody in chronically infected persons. A recombinant parvoVirus B19 vaccine is under development.
Keizo Nagasaki - One of the best experts on this subject based on the ideXlab platform.
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Isolation and characterisation of a Single-Stranded DNA Virus infecting the marine planktonic diatom Chaetoceros tenuissimus
Aquatic Microbial Ecology, 2011Co-Authors: Yuji Tomaru, Yoko Shirai, Kensuke Toyoda, Keizo NagasakiAbstract:Diatoms are important components of the biological community and food web in the aquatic environment. Here, we report the characteristics of a Single-Stranded RNA (ssRNA) Virus (CtenRNAV01) that infects the marine diatom Chaetoceros tenuissimus Meunier (Bacillariophyceae). The ca. 31-nm Virus particle is icosahedral and lacks a tail. CtenRNAV01 forms crystalline arrays occupying most of the infected host’s cytoplasm. By growth experiments, the lytic cycle and the burst size were estimated to be
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Isolation and Characterization of a Single-Stranded DNA Virus Infecting Chaetoceros lorenzianus Grunow
Applied and Environmental Microbiology, 2011Co-Authors: Yuji Tomaru, Yoshitake Takao, Hidekazu Suzuki, Tamotsu Nagumo, Kanae Koike, Keizo NagasakiAbstract:Diatoms are one of the most significant primary producers in the ocean, and the importance of Viruses as a potential source of mortality for diatoms has recently been recognized. Thus far, eight different diatom Viruses infecting the genera Rhizosolenia and Chaetoceros have been isolated and characterized to different extents. We report the isolation of a novel diatom Virus (ClorDNAV), which causes the lysis of the bloom-forming species Chaetoceros lorenzianus, and show its physiological, morphological, and genomic characteristics. The free virion was estimated to be ∼34 nm in diameter. The arrangement of Virus particles appearing in cross-section was basically a random aggregation in the nucleus. Occasionally, distinctive formations such as a ring-like array composed of 9 or 10 spherical virions or a centipede-like array composed of rod-shaped particles were also observed. The latent period and the burst size were estimated to be
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Isolation and characterization of a new Single-Stranded DNA Virus infecting the cosmopolitan marine diatom Chaetoceros debilis
Aquatic Microbial Ecology, 2008Co-Authors: Yuji Tomaru, Hidekazu Suzuki, Tamotsu Nagumo, Yoko Shirai, Keizo NagasakiAbstract:The genus Chaetoceros (Bacillariophyceae) is the dominant diatom in the world's oceans. Various physical, chemical and biological factors affect depletion of diatom populations, for which the importance of Viruses as a potential mortality source has only recently been found. We isolated and characterized a new Chaetoceros-infecting Virus causing the lysis of the cosmopolitan species C. debilis Cleve. The Virus infectious for C. debilis was isolated from both water and sediment samples collected in western Japan. We show the physiologic, morphologic and genomic characteristics of one Virus clone among many isolates. We first described the C. debilis DNA Virus (CdebDNAV), a 30 nm icosahedral Virus accumulating in the cytoplasm of C. debilis. Host specificity of CdebDNAV is strain-specific and its infectivity is stably maintained through a wide temperature range (between 20 and -196°C). The latent period and the burst size were estimated to be 12 to 24 h and 55 infectious units per host cell, respectively. CdebDNAV harbors a Single-Stranded DNA (ssDNA) genome whose structure is unknown. Sequence comparisons showed that the partial sequence of CdebDNAV is highly similar (E value = 10 -56 ) to the putative replicase gene of the C. salsugineum nuclear inclusion Virus (CsNIV) that harbors a covalently closed circular, partially doublestranded ssDNA genome. This discovery of CdebDNAV may aid in further understanding the ecological dynamics of C. debilis population blooms in nature.
Riza Durmaz - One of the best experts on this subject based on the ideXlab platform.
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transfusion transmitted Virus DNA in serum tear and aqueous humour of patients undergoing cataract operation
Clinical and Experimental Ophthalmology, 2007Co-Authors: Sinan Emre, Baris Otlu, Cem Cankaya, Selim Doganay, Riza DurmazAbstract:Purpose: Transfusion-transmitted Virus (TTV) is a novel non-enveloped, Single-Stranded DNA Virus with unclear pathogenesis throughout the world. Many studies were conducted to determine this Virus in various body fluids and different primer sets have been tested for accurate diagnosis. This study aimed to collect data on the prevalence of TTV in serum, tear and aqueous humour of patients undergoing planned cataract surgery and to determine efficacy of three different polymerase chain reaction (PCR) techniques. Methods: A total of 72 specimens (24 each of serum, tear and aqueous humour specimens) were collected from 24 patients (11 male and 13 female) having age-related cataract. The patients did not have any other ocular pathology. TTV DNA was investigated by three different PCR methods: a seminested PCR performed with Okamato's primers, a one-step PCR performed with degenerative Takashi's primers and a commercial real-time PCR system. Results: TTV DNA was detected in 20 (83.3%) of the 24 serum specimens by the one-step PCR and real-time PCR system. However, seminested PCR yielded a positivity rate of 25%. TTV DNA positivities of the one-step PCR and the real-time PCR system were 33.3% and 66.6% of the 24 tear specimens, respectively. Seminested PCR did not yield positive result in these specimens. From aqueous humour specimens, TTV DNA was detected in 3 (12.5%) of the 24 specimens only by the real-time PCR. TTV DNA positivity of seminested PCR was significantly low in all specimens. Conclusions: TTV DNA was detected in serum, tear and aqueous humour of patients undergoing cataract surgery, supporting the idea that this Virus can be detected almost all of the body fluids but at different rates under various PCR conditions and primer sets. Using commercial real-time PCR significantly increased the TTV DNA positivity.