Displaying publications 21 - 40 of 154 in total

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  1. Genetic variability of genome segments 3 and 9 of Fiji disease virus field isolates
    Jiang J, Ridley AW, Tang H, Croft BJ, Johnson KN
    Arch Virol, 2008;153(5):839-48.
    PMID: 18299794 DOI: 10.1007/s00705-008-0058-1
    Fiji leaf gall is an important disease of sugarcane in Australia and other Asia-Pacific countries. The causative agent is the reovirus Fiji disease virus (FDV). Previous reports indicate that there is variation in pathology between virus isolates. To investigate the amount of genetic variation found in FDV, 25 field isolates from Australia, Papua New Guinea and Malaysia were analysed by partial sequencing of genome segments S3 and S9. There was up to 15% divergence in the nucleotide sequence among the 25 isolates. A similar amount of divergence and pattern of relationships was found for each of the two genomic segments for most of the field isolates, although reassortment of genome segments seems likely for at least one of the Papua New Guinean isolates. The finding of a high level of variation in FDV isolated in different regions has implications for quarantine and disease management.
    Matched MeSH terms: Genome, Viral
  2. Fulltext Terrestrial Animal-Derived Rabies Virus in a Juvenile Indian Flying Fox in Sri Lanka
    Matsumoto T, Nanayakkara S, Perera D, Ushijima S, Wimalaratne O, Nishizono A, et al.
    Jpn J Infect Dis, 2017 Nov 22;70(6):693-695.
    PMID: 29093322 DOI: 10.7883/yoken.JJID.2017.249
    Matched MeSH terms: Genome, Viral
  3. Fulltext Possible Roles of New Mutations Shared by Asian and American Zika Viruses
    Yokoyama S, Starmer WT
    Mol Biol Evol, 2017 03 01;34(3):525-534.
    PMID: 28087772 DOI: 10.1093/molbev/msw270
    Originating in Africa, the Zika virus (ZIKV) has spread to Asia, Pacific Islands and now to the Americas and beyond. Since the first isolation in 1947, ZIKV strains have been sampled at various times in the last 69 years, but this history has not been reflected in studying the patterns of mutation accumulation in their genomes. Implementing the viral history, we show that the ZIKV ancestor appeared sometime in 1930-1945 and, at that point, its mutation rate was probably less than 0.2 × 10-3/nucleotide site/year and subsequently increased significantly in most of its descendants. Sustaining a high mutation rate of 4 × 10-3/site/year throughout its evolution, the Ancestral Asian strain, which was sampled from a mosquito in Malaysia, accumulated 13 mutations in the 3'-untranslated region of RNA stem-loops prior to 1963, seven of which generate more stable stem-loop structures and are likely to inhibit cellular antiviral activities, including immune and RNA interference (RNAi) pathways. The seven mutations have been maintained in all Asian and American strains and may be responsible for serious medical problems we are facing today and offer testable hypotheses to examine their roles in molecular interactions during brain development.
    Matched MeSH terms: Genome, Viral
  4. Optimization and Implementation of the Virus Extraction Method for Hepatitis E Virus Detection from Raw Pork Liver
    Zhao MY, Li D
    Food Environ Virol, 2021 03;13(1):74-83.
    PMID: 33449335 DOI: 10.1007/s12560-020-09452-y
    Hepatitis E virus (HEV) has been frequently detected from pork liver and liver products, which can usually cause self-limiting diseases in healthy adults, yet may result in fatality in immunosuppressed groups. Nevertheless, there is so far no standardized method for HEV detection available from pork liver and/or liver products. The present study aimed to optimize the virus extraction method of HEV from raw pork liver, which is often consumed in Asia undercooked to avoid a grainy texture. By comparing different sample preparation protocols and by applying the selected protocol to 60 samples collected from Singapore retail markets, we demonstrated that homogenization of 0.25 g raw pork liver with FastPrep™ Lysing Matrix Y containing yttria-stabilized zircondium oxide beads in 2 ml tubes and with harsh mechanical force at 6 ms-1, 40 s/cycle, for 5 cycles with 300 s pause time after each cycle is promising in both releasing the potentially intracellular viruses and resulting in satisfactory virus recovery rates (> 1%). A high prevalence (52%) of HEV genome was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) from the 60 samples collected from Singapore retail markets imported from Indonesia, Australia and Malaysia. However, RNase treatment decreased the HEV prevalence to 33.3%, and all of the 20 positive samples were with high RT-qPCR Ct values above 35, suggesting that the positive RT-qPCR signals maybe largely due to the inactive viruses and/or exposed HEV RNA traces in raw pork liver products. Therefore, conscious care should be taken when interpreting molecular detection results of viruses from food samples to be correlated with public health risks.
    Matched MeSH terms: Genome, Viral
  5. Fulltext Whole-Genome Phylogenetic Analysis of Influenza B/Phuket/3073/2013-Like Viruses and Unique Reassortants Detected in Malaysia between 2012 and 2014
    Oong XY, Ng KT, Tan JL, Chan KG, Kamarulzaman A, Chan YF, et al.
    PLoS One, 2017;12(1):e0170610.
    PMID: 28129386 DOI: 10.1371/journal.pone.0170610
    Reassortment of genetic segments between and within influenza B lineages (Victoria and Yamagata) has been shown to generate novel reassortants with unique genetic characteristics. Based on hemagglutinin (HA) and neuraminidase (NA) genes, recent surveillance study has identified reassortment properties in B/Phuket/3073/2013-like virus, which is currently used in the WHO-recommended influenza vaccine. To understand the potential reassortment patterns for all gene segments, four B/Phuket/3073/2013-like viruses and two unique reassortants (one each from Yamagata and Victoria) detected in Malaysia from 2012-2014 were subjected to whole-genome sequencing. Each gene was phylogenetically classified into lineages, clades and sub-clades. Three B/Phuket/3073/2013-like viruses from Yamagata lineage were found to be intra-clade reassortants, possessing PA and NA genes derived from Stockholm/12-like sub-clade, while the remaining genes from Wisconsin/01-like sub-clade (both sub-clades were within Yamagata Clade 3/Yam-3). However, the other B/Phuket/3073/2013-like virus had NS gene that derived from Stockholm/12-like sub-clade instead of Wisconsin/01-like sub-clade. One inter-clade reassortant had Yamagata Clade 2/Yam-2-derived HA and NP, and its remaining genes were Yam-3-derived. Within Victoria Clade 1/Vic-1 in Victoria lineage, one virus had intra-clade reassortment properties: HA and PB2 from Vic-1B sub-clade, MP and NS from a unique sub-clade "Vic-1C", and the remaining genes from Vic-1A sub-clade. Although random reassortment event may generate unique reassortants, detailed phylogenetic classification of gene segments showed possible genetic linkage between PA and NA genes in B/Phuket/3073/2013-like viruses, which requires further investigation. Understanding on reassortment patterns in influenza B evolution may contribute to future vaccine design.
    Matched MeSH terms: Genome, Viral
  6. The presence of duck Tembusu virus in Thailand since 2007: A retrospective study
    Ninvilai P, Nonthabenjawan N, Limcharoen B, Tunterak W, Oraveerakul K, Banlunara W, et al.
    Transbound Emerg Dis, 2018 Oct;65(5):1208-1216.
    PMID: 29520997 DOI: 10.1111/tbed.12859
    Duck Tembusu virus (DTMUV), a newly emerging virus in ducks, was first reported in China in 2010. However, an unknown severe contagious disease associated with severe neurological signs and egg production losses in ducks, resembling to DTMUV infection, was observed in Thailand since 2007. To determine the presence of DTMUV in 2007, the clinical samples from affected ducks collected in 2007 were tested for DTMUV using pathological and virological analyses. Gross and histopathological lesions of affected ducks were mostly restricted to the ovary, brain and spinal cord, and correlated with the presence of flavivirus antigen in the brain and spinal cord samples. Subsequently, DTMUV was identified by RT-PCR and nucleotide sequencing of the polyprotein gene. Phylogenetic analysis of the polyprotein gene sequence revealed that the 2007 Thai DTMUV was a unique virus, belonged within DTMUV cluster 1, but distinctively separated from the Malaysian DTMUV, which was the most closely related DTMUV. It is interesting to note that the 2007 Thai DTMUV was genetically different from the currently circulating Thai and Chinese DTMUVs, which belonged to cluster 2. Our findings indicated that the 2007 Thai DTMUV emerged earlier from a common ancestor with the recently reported DTMUVs; however, it was genetically distinctive to any of the currently circulating DTMUVs. In conclusion, our data demonstrated the presence of DTMUV in the Thai ducks since 2007, prior to the first report of DTMUV in China in 2010. This study indicates that DTMUV may have circulated in the region long before 2010 and highlights high genetic diversity of DTMUVs in Asia.
    Matched MeSH terms: Genome, Viral
  7. Fulltext Phylogeography, Transmission, and Viral Proteins of Nipah Virus
    Sun B, Jia L, Liang B, Chen Q, Liu D
    Virol Sin, 2018 Oct;33(5):385-393.
    PMID: 30311101 DOI: 10.1007/s12250-018-0050-1
    Nipah virus (NiV), a zoonotic paramyxovirus belonging to the genus Henipavirus, is classified as a Biosafety Level-4 pathogen based on its high pathogenicity in humans and the lack of available vaccines or therapeutics. Since its initial emergence in 1998 in Malaysia, this virus has become a great threat to domestic animals and humans. Sporadic outbreaks and person-to-person transmission over the past two decades have resulted in hundreds of human fatalities. Epidemiological surveys have shown that NiV is distributed in Asia, Africa, and the South Pacific Ocean, and is transmitted by its natural reservoir, Pteropid bats. Numerous efforts have been made to analyze viral protein function and structure to develop feasible strategies for drug design. Increasing surveillance and preventative measures for the viral infectious disease are urgently needed.
    Matched MeSH terms: Genome, Viral
  8. Fulltext Pteropid bats are confirmed as the reservoir hosts of henipaviruses: a comprehensive experimental study of virus transmission
    Halpin K, Hyatt AD, Fogarty R, Middleton D, Bingham J, Epstein JH, et al.
    Am J Trop Med Hyg, 2011 Nov;85(5):946-51.
    PMID: 22049055 DOI: 10.4269/ajtmh.2011.10-0567
    Bats of the genus Pteropus have been identified as the reservoir hosts for the henipaviruses Hendra virus (HeV) and Nipah virus (NiV). The aim of these studies was to assess likely mechanisms for henipaviruses transmission from bats. In a series of experiments, Pteropus bats from Malaysia and Australia were inoculated with NiV and HeV, respectively, by natural routes of infection. Despite an intensive sampling strategy, no NiV was recovered from the Malaysian bats and HeV was reisolated from only one Australian bat; no disease was seen. These experiments suggest that opportunities for henipavirus transmission may be limited; therefore, the probability of a spillover event is low. For spillover to occur, a range of conditions and events must coincide. An alternate assessment framework is required if we are to fully understand how this reservoir host maintains and transmits not only these but all viruses with which it has been associated.
    Matched MeSH terms: Genome, Viral
  9. Fulltext Molecular detection and characterisation of Domestic Cat Hepadnavirus (DCH) from blood and liver tissues of cats in Malaysia
    Anpuanandam K, Selvarajah GT, Choy MMK, Ng SW, Kumar K, Ali RM, et al.
    BMC Vet Res, 2021 Jan 06;17(1):9.
    PMID: 33407487 DOI: 10.1186/s12917-020-02700-0
    BACKGROUND: A new domestic cat hepadnavirus (DCH, family Hepadnaviridae) was first reported from whole blood samples of domestic cats in Australia in 2018, and from cat serum samples in Italy in 2019. The pathogenesis of DCH is unknown, but it was reported in cats with viraemia (6.5-10.8%), chronic hepatitis (43%) and hepatocellular carcinoma (28%). Recent reports suggest that DCH resembles the human hepatitis B virus (HBV) and its related hepatopathies. This study aims to detect and characterize DCH among domestic cats in Malaysia. A cross-sectional study was performed on 253 cats, of which 87 had paired blood and liver samples, entailing whole-genome sequencing and phylogenetic analysis of DCH from a liver tissue sample.

    RESULTS: Among the 253 cats included in this study, 12.3% of the whole blood samples tested positive for DCH. The detection rate was significantly higher in pet cats (16.6%, n = 24/145) compared to shelter cats (6.5%, n = 7/108). Liver tissues showed higher a DCH detection rate (14.9%, n = 13/87) compared to blood; 5 out of these 13 cats tested positive for DCH in their paired liver and blood samples. Serum alanine transaminase (ALT) was elevated (> 95 units/L) in 12 out of the 23 DCH-positive cats (52.2%, p = 0.012). Whole-genome sequence analysis revealed that the Malaysian DCH strain, with a genome size of 3184 bp, had 98.3% and 97.5% nucleotide identities to the Australian and Italian strains, respectively. The phylogenetic analysis demonstrated that the Malaysian DCH genome was clustered closely to the Australian strain, suggesting that they belong to the same geographically-determined genetic pool (Australasia).

    CONCLUSIONS: This study provided insights into a Malaysian DCH strain that was detected from a liver tissue. Interestingly, pet cats or cats with elevated ALT were significantly more likely to be DCH positive. Cats with positive DCH detection from liver tissues may not necessarily have viraemia. The impact of this virus on inducing liver diseases in felines warrants further investigation.

    Matched MeSH terms: Genome, Viral
  10. Hendra and Nipah viruses: different and dangerous
    Eaton BT, Broder CC, Middleton D, Wang LF
    Nat Rev Microbiol, 2006 Jan;4(1):23-35.
    PMID: 16357858
    Hendra virus and Nipah virus are highly pathogenic paramyxoviruses that have recently emerged from flying foxes to cause serious disease outbreaks in humans and livestock in Australia, Malaysia, Singapore and Bangladesh. Their unique genetic constitution, high virulence and wide host range set them apart from other paramyxoviruses. These features led to their classification into the new genus Henipavirus within the family Paramyxoviridae and to their designation as Biosafety Level 4 pathogens. This review provides an overview of henipaviruses and the types of infection they cause, and describes how studies on the structure and function of henipavirus proteins expressed from cloned genes have provided insights into the unique biological properties of these emerging human pathogens.
    Matched MeSH terms: Genome, Viral
  11. Fulltext Klebsiella virus UPM2146 lyses multiple drug-resistant Klebsiella pneumoniae in vitro and in vivo
    Assafiri O, Song AA, Tan GH, Hanish I, Hashim AM, Yusoff K
    PLoS One, 2021;16(1):e0245354.
    PMID: 33418559 DOI: 10.1371/journal.pone.0245354
    Klebsiella pneumoniae are opportunistic bacteria found in the gut. In recent years they have been associated with nosocomial infections. The increased incidence of multiple drug-resistant K. pneumoniae makes it necessary to find new alternatives to treat the disease. In this study, phage UPM2146 was isolated from a polluted lake which can lyse its host K. pneumoniae ATCC BAA-2146. Observation from TEM shows that UPM2146 belongs to Caudoviriales (Order) based on morphological appearance. Whole genome analysis of UPM2146 showed that its genome comprises 160,795 bp encoding for 214 putative open reading frames (ORFs). Phylogenetic analysis revealed that the phage belongs to Ackermannviridae (Family) under the Caudoviriales. UPM2146 produces clear plaques with high titers of 1010 PFU/ml. The phage has an adsorption period of 4 min, latent period of 20 min, rise period of 5 min, and releases approximately 20 PFU/ bacteria at Multiplicity of Infection (MOI) of 0.001. UPM2146 has a narrow host-range and can lyse 5 out of 22 K. pneumoniae isolates (22.72%) based on spot test and efficiency of plating (EOP). The zebrafish larvae model was used to test the efficacy of UPM2146 in lysing its host. Based on colony forming unit counts, UPM2146 was able to completely lyse its host at 10 hours onwards. Moreover, we show that the phage is safe to be used in the treatment against K. pneumoniae infections in the zebrafish model.
    Matched MeSH terms: Genome, Viral
  12. Fulltext Emergence of Japanese encephalitis virus genotype V in the Republic of Korea
    Takhampunya R, Kim HC, Tippayachai B, Kengluecha A, Klein TA, Lee WJ, et al.
    Virol J, 2011;8:449.
    PMID: 21943222 DOI: 10.1186/1743-422X-8-449
    Japanese encephalitis virus (JEV) genotype V reemerged in Asia (China) in 2009 after a 57-year hiatus from the continent, thereby emphasizing a need to increase regional surveillance efforts. Genotypic characterization was performed on 19 JEV-positive mosquito pools (18 pools of Culex tritaeniorhynchus and 1 pool of Cx. bitaeniorhynchus) from a total of 64 positive pools collected from geographically different locations throughout the Republic of Korea (ROK) during 2008 and 2010.
    Matched MeSH terms: Genome, Viral*
  13. Small circular single stranded DNA viral genomes in unexplained cases of human encephalitis, diarrhea, and in untreated sewage
    Phan TG, Mori D, Deng X, Rajindrajith S, Ranawaka U, Fan Ng TF, et al.
    Virology, 2015 Aug;482:98-104.
    PMID: 25839169 DOI: 10.1016/j.virol.2015.03.011
    Viruses with small circular ssDNA genomes encoding a replication initiator protein can infect a wide range of eukaryotic organisms ranging from mammals to fungi. The genomes of two such viruses, a cyclovirus (CyCV-SL) and gemycircularvirus (GemyCV-SL) were detected by deep sequencing of the cerebrospinal fluids of Sri Lankan patients with unexplained encephalitis. One and three out of 201 CSF samples (1.5%) from unexplained encephalitis patients tested by PCR were CyCV-SL and GemyCV-SL DNA positive respectively. Nucleotide similarity searches of pre-existing metagenomics datasets revealed closely related genomes in feces from unexplained cases of diarrhea from Nicaragua and Brazil and in untreated sewage from Nepal. Whether the tropism of the cyclovirus and gemycircularvirus reported here include humans or other cellular sources in or on the human body remains to be determined.
    Matched MeSH terms: Genome, Viral*
  14. A review of Nipah and Hendra viruses with an historical aside
    Ksiazek TG, Rota PA, Rollin PE
    Virus Res, 2011 Dec;162(1-2):173-83.
    PMID: 21963678 DOI: 10.1016/j.virusres.2011.09.026
    The emergence of Hendra and Nipah viruses in the 1990s has been followed by the further emergence of these viruses in the tropical Old World. The history and current knowledge of the disease, the viruses and their epidemiology is reviewed in this article. A historical aside summarizes the role that Dr. Brian W.J. Mahy played at critical junctures in the early stories of these viruses.
    Matched MeSH terms: Genome, Viral*
  15. Isolation of SARS-CoV-2-related coronavirus from Malayan pangolins
    Xiao K, Zhai J, Feng Y, Zhou N, Zhang X, Zou JJ, et al.
    Nature, 2020 07;583(7815):286-289.
    PMID: 32380510 DOI: 10.1038/s41586-020-2313-x
    The current outbreak of coronavirus disease-2019 (COVID-19) poses unprecedented challenges to global health1. The new coronavirus responsible for this outbreak-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-shares high sequence identity to SARS-CoV and a bat coronavirus, RaTG132. Although bats may be the reservoir host for a variety of coronaviruses3,4, it remains unknown whether SARS-CoV-2 has additional host species. Here we show that a coronavirus, which we name pangolin-CoV, isolated from a Malayan pangolin has 100%, 98.6%, 97.8% and 90.7% amino acid identity with SARS-CoV-2 in the E, M, N and S proteins, respectively. In particular, the receptor-binding domain of the S protein of pangolin-CoV is almost identical to that of SARS-CoV-2, with one difference in a noncritical amino acid. Our comparative genomic analysis suggests that SARS-CoV-2 may have originated in the recombination of a virus similar to pangolin-CoV with one similar to RaTG13. Pangolin-CoV was detected in 17 out of the 25 Malayan pangolins that we analysed. Infected pangolins showed clinical signs and histological changes, and circulating antibodies against pangolin-CoV reacted with the S protein of SARS-CoV-2. The isolation of a coronavirus from pangolins that is closely related to SARS-CoV-2 suggests that these animals have the potential to act as an intermediate host of SARS-CoV-2. This newly identified coronavirus from pangolins-the most-trafficked mammal in the illegal wildlife trade-could represent a future threat to public health if wildlife trade is not effectively controlled.
    Matched MeSH terms: Genome, Viral/genetics*
  16. Tembusu-like flavivirus (Perak virus) as the cause of neurological disease outbreaks in young Pekin ducks
    Homonnay ZG, Kovács EW, Bányai K, Albert M, Fehér E, Mató T, et al.
    Avian Pathol, 2014;43(6):552-60.
    PMID: 25299764 DOI: 10.1080/03079457.2014.973832
    A neurological disease of young Pekin ducks characterized by ataxia, lameness, and paralysis was observed at several duck farms in Malaysia in 2012. Gross pathological lesions were absent or inconsistent in most of the cases, but severe and consistent microscopic lesions were found in the brain and spinal cord, characterized by non-purulent panencephalomyelitis. Several virus isolates were obtained in embryonated duck eggs and in cell cultures (Vero and DF-1) inoculated with the brain homogenates of affected ducks. After exclusion of other viruses, the isolates were identified as a flavivirus by flavivirus-specific reverse transcription-polymerase chain reaction (RT-PCR) assays. Inoculation of 2-week-old Pekin ducks with a flavivirus isolate by the subcutaneous or intramuscular route resulted in typical clinical signs and histological lesions in the brain and spinal cord. The inoculated virus was detected by RT-PCR from organ samples of ducks with clinical signs and histological lesions. With a few days delay, the disease was also observed among co-mingled contact control birds. Phylogenetic analysis of NS5 and E gene sequences proved that the isolates were representatives of a novel phylogenetic group within clade XI (Ntaya virus group) of the Flavivirus genus. This Malaysian Duck Tembusu Virus (DTMUV), named Perak virus, has moderate genomic RNA sequence similarity to a related DTMUV identified in China. In our experiment the Malaysian strain of DTMUV could be transmitted in the absence of mosquito vectors. These findings may have implications for the control and prevention of this emerging group of flaviviruses.
    Matched MeSH terms: Genome, Viral/genetics*
  17. Fulltext Development of live attenuated Enterovirus 71 vaccine strains that confer protection against lethal challenge in mice
    Yee PTI, Tan SH, Ong KC, Tan KO, Wong KT, Hassan SS, et al.
    Sci Rep, 2019 03 18;9(1):4805.
    PMID: 30886246 DOI: 10.1038/s41598-019-41285-z
    Besides causing mild hand, foot and mouth infections, Enterovirus A71 (EV-A71) is associated with neurological complications and fatality. With concerns about rising EV-A71 virulence, there is an urgency for more effective vaccines. The live attenuated vaccine (LAV) is a more valuable vaccine as it can elicit both humoral and cellular immune responses. A miRNA-based vaccine strain (pIY) carrying let-7a and miR-124a target genes in the EV-A71 genome which has a partial deletion in the 5'NTR (∆11 bp) and G64R mutation (3Dp°l) was designed. The viral RNA copy number and viral titers of the pIY strain were significantly lower in SHSY-5Y cells that expressed both let-7a and miR-124a. Inhibition of the cognate miRNAs expressed in RD and SHSY-5Y cells demonstrated de-repression of viral mRNA translation. A previously constructed multiply mutated strain, MMS and the pIY vaccine strain were assessed in their ability to protect 4-week old mice from hind limb paralysis. The MMS showed higher amounts of IFN-γ ex vivo than the pIY vaccine strain. There was absence of EV-A71 antigen in the skeletal muscles and spinal cord micrographs of mice vaccinated with the MMS and pIY strains. The MMS and pIY strains are promising LAV candidates developed against severe EV-A71 infections.
    Matched MeSH terms: Genome, Viral/genetics
  18. Fulltext Global genomic diversity of human papillomavirus 6 based on 724 isolates and 190 complete genome sequences
    Jelen MM, Chen Z, Kocjan BJ, Burt FJ, Chan PK, Chouhy D, et al.
    J Virol, 2014 Jul;88(13):7307-16.
    PMID: 24741079 DOI: 10.1128/JVI.00621-14
    Human papillomavirus type 6 (HPV6) is the major etiological agent of anogenital warts and laryngeal papillomas and has been included in both the quadrivalent and nonavalent prophylactic HPV vaccines. This study investigated the global genomic diversity of HPV6, using 724 isolates and 190 complete genomes from six continents, and the association of HPV6 genomic variants with geographical location, anatomical site of infection/disease, and gender. Initially, a 2,800-bp E5a-E5b-L1-LCR fragment was sequenced from 492/530 (92.8%) HPV6-positive samples collected for this study. Among them, 130 exhibited at least one single nucleotide polymorphism (SNP), indel, or amino acid change in the E5a-E5b-L1-LCR fragment and were sequenced in full. A global alignment and maximum likelihood tree of 190 complete HPV6 genomes (130 fully sequenced in this study and 60 obtained from sequence repositories) revealed two variant lineages, A and B, and five B sublineages: B1, B2, B3, B4, and B5. HPV6 (sub)lineage-specific SNPs and a 960-bp representative region for whole-genome-based phylogenetic clustering within the L2 open reading frame were identified. Multivariate logistic regression analysis revealed that lineage B predominated globally. Sublineage B3 was more common in Africa and North and South America, and lineage A was more common in Asia. Sublineages B1 and B3 were associated with anogenital infections, indicating a potential lesion-specific predilection of some HPV6 sublineages. Females had higher odds for infection with sublineage B3 than males. In conclusion, a global HPV6 phylogenetic analysis revealed the existence of two variant lineages and five sublineages, showing some degree of ethnogeographic, gender, and/or disease predilection in their distribution.

    IMPORTANCE: This study established the largest database of globally circulating HPV6 genomic variants and contributed a total of 130 new, complete HPV6 genome sequences to available sequence repositories. Two HPV6 variant lineages and five sublineages were identified and showed some degree of association with geographical location, anatomical site of infection/disease, and/or gender. We additionally identified several HPV6 lineage- and sublineage-specific SNPs to facilitate the identification of HPV6 variants and determined a representative region within the L2 gene that is suitable for HPV6 whole-genome-based phylogenetic analysis. This study complements and significantly expands the current knowledge of HPV6 genetic diversity and forms a comprehensive basis for future epidemiological, evolutionary, functional, pathogenicity, vaccination, and molecular assay development studies.

    Matched MeSH terms: Genome, Viral/genetics*
  19. Molecular phylogenetic and evolutionary analyses of Muar strain of Japanese encephalitis virus reveal it is the missing fifth genotype
    Mohammed MA, Galbraith SE, Radford AD, Dove W, Takasaki T, Kurane I, et al.
    Infect Genet Evol, 2011 Jul;11(5):855-62.
    PMID: 21352956 DOI: 10.1016/j.meegid.2011.01.020
    Japanese encephalitis virus (JEV) is the most important cause of epidemic encephalitis worldwide but its origin is unknown. Epidemics of encephalitis suggestive of Japanese encephalitis (JE) were described in Japan from the 1870s onwards. Four genotypes of JEV have been characterised and representatives of each genotype have been fully sequenced. Based on limited information, a single isolate from Malaysia is thought to represent a putative fifth genotype. We have determined the complete nucleotide and amino acid sequence of Muar strain and compared it with other fully sequenced JEV genomes. Muar was the least similar, with nucleotide divergence ranging from 20.2 to 21.2% and amino acid divergence ranging from 8.5 to 9.9%. Phylogenetic analysis of Muar strain revealed that it does represent a distinct fifth genotype of JEV. We elucidated Muar signature amino acids in the envelope (E) protein, including E327 Glu on the exposed lateral surface of the putative receptor binding domain which distinguishes Muar strain from the other four genotypes. Evolutionary analysis of full-length JEV genomes revealed that the mean evolutionary rate is 4.35 × 10(-4) (3.4906 × 10(-4) to 5.303 × 10(-4)) nucleotides substitutions per site per year and suggests JEV originated from its ancestral virus in the mid 1500s in the Indonesia-Malaysia region and evolved there into different genotypes, which then spread across Asia. No strong evidence for positive selection was found between JEV strains of the five genotypes and the E gene has generally been subjected to strong purifying selection.
    Matched MeSH terms: Genome, Viral
  20. Fulltext Simple and cost-effective restriction endonuclease analysis of human adenoviruses
    Adhikary AK, Hanaoka N, Fujimoto T
    Biomed Res Int, 2014;2014:363790.
    PMID: 24734232 DOI: 10.1155/2014/363790
    Restriction endonuclease analyses (REAs) constitute the only inexpensive molecular approach capable of typing and characterizing human adenovirus (HAdV) strains based on the entire genome. However, the application of this method is limited by the need for time-consuming and labor-intensive procedures. We herein developed a simple and cost-effective REA for assessing HAdV. The method consists of (1) simple and cost-effective DNA extraction, (2) fast restriction endonuclease (RE) digestion, and (3) speedy mini agarose gel electrophoresis. In this study, DNA was isolated according to the kit-based method and 21.0 to 28.0  μg of viral DNA was extracted from prototypes (HAdV-1, HAdV-3, HAdV-4, and HAdV-37) in each flask. The amount of DNA ranged from 11.4 to 57.0  μg among the HAdV-3 (n=73) isolates. The obtained viral DNA was found to be applicable to more than 10 types of REAs. Fast-cut restriction endonucleases (REs) were able to digest the DNA within 15 minutes, and restriction fragments were easily separated via horizontal mini agarose gel electrophoresis. The whole procedure for 10 samples can be completed within approximately six hours (the conventional method requires at least two days). These results show that our REA is potentially applicable in many laboratories in which HAdVs are isolated.
    Matched MeSH terms: Genome, Viral
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