Displaying publications 1 - 20 of 64 in total

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  1. Zhang W, Liang Y, Zheng K, Gu C, Liu Y, Wang Z, et al.
    BMC Genomics, 2021 Sep 20;22(1):675.
    PMID: 34544379 DOI: 10.1186/s12864-021-07978-4
    BACKGROUND: Marine bacteriophages play key roles in the community structure of microorganisms, biogeochemical cycles, and the mediation of genetic diversity through horizontal gene transfer. Recently, traditional isolation methods, complemented by high-throughput sequencing metagenomics technology, have greatly increased our understanding of the diversity of bacteriophages. Oceanospirillum, within the order Oceanospirillales, are important symbiotic marine bacteria associated with hydrocarbon degradation and algal blooms, especially in polar regions. However, until now there has been no isolate of an Oceanospirillum bacteriophage, and so details of their metagenome has remained unknown.

    RESULTS: Here, we reported the first Oceanospirillum phage, vB_OliS_GJ44, which was assembled into a 33,786 bp linear dsDNA genome, which includes abundant tail-related and recombinant proteins. The recombinant module was highly adapted to the host, according to the tetranucleotides correlations. Genomic and morphological analyses identified vB_OliS_GJ44 as a siphovirus, however, due to the distant evolutionary relationship with any other known siphovirus, it is proposed that this virus could be classified as the type phage of a new Oceanospirivirus genus within the Siphoviridae family. vB_OliS_GJ44 showed synteny with six uncultured phages, which supports its representation in uncultured environmental viral contigs from metagenomics. Homologs of several vB_OliS_GJ44 genes have mostly been found in marine metagenomes, suggesting the prevalence of this phage genus in the oceans.

    CONCLUSIONS: These results describe the first Oceanospirillum phage, vB_OliS_GJ44, that represents a novel viral cluster and exhibits interesting genetic features related to phage-host interactions and evolution. Thus, we propose a new viral genus Oceanospirivirus within the Siphoviridae family to reconcile this cluster, with vB_OliS_GJ44 as a representative member.

    Matched MeSH terms: DNA, Viral/genetics
  2. Goot-Heah K, Kwai-Lin T, Froemming GR, Abraham MT, Nik Mohd Rosdy NM, Zain RB
    Asian Pac J Cancer Prev, 2012;13(12):6109-13.
    PMID: 23464414
    BACKGROUND: Oral cancer has become one of the most prevalent cancers worldwide and human Papillomavirus is one of the risk factors for developing oral cancer. For this study HPV18 was chosen as it is one of the high risk HPV types and may lead to carcinogenesis. However, prevalence of HPV18 infection in Oral Squamous Cell Carcinoma in Malaysia remains unclear.

    OBJECTIVE: This study aimed to investigate the viral load of HPV18 DNA in OSCC and potentially malignant lesions using saliva samples.

    MATERIALS AND METHODS: Genomic DNAs of thirty saliva samples of normal subjects and thirty saliva samples compromised of 16 samples from potentially malignant lesions and 14 of OSCC patients were amplified for HPV18 DNA using a nested polymerase chain reaction analysis. All PCR products were then analyzed using the Bioanalyzer to confirm presence of HPV18 DNA.

    RESULT: From thirty patients examined, only one of 30 (3.3%) cases was found to be positive for HPV18 in this study.

    CONCLUSION: The finding of this study revealed that there is a low viral detection of HPV18 in Malaysian OSCC by using saliva samples, suggesting that prevalence of HPV18 may not be important in this group of Malaysian OSCC.

    Matched MeSH terms: DNA, Viral/genetics
  3. Wang H, Ren L, Liang Y, Zheng K, Guo R, Liu Y, et al.
    Microbiol Spectr, 2023 Aug 17;11(4):e0533522.
    PMID: 37272818 DOI: 10.1128/spectrum.05335-22
    Psychrobacter is an important bacterial genus that is widespread in Antarctic and marine environments. However, to date, only two complete Psychrobacter phage sequences have been deposited in the NCBI database. Here, the novel Psychrobacter phage vB_PmaS_Y8A, infecting Psychrobacter HM08A, was isolated from sewage in the Qingdao area, China. The morphology of vB_PmaS_Y8A was characterized by transmission electron microscopy, revealing an icosahedral head and long tail. The genomic sequence of vB_PmaS_Y8A is linear, double-stranded DNA with a length of 40,226 bp and 44.1% G+C content, and encodes 69 putative open reading frames. Two auxiliary metabolic genes (AMGs) were identified, encoding phosphoadenosine phosphosulfate reductase and MarR protein. The first AMG uses thioredoxin as an electron donor for the reduction of phosphoadenosine phosphosulfate to phosphoadenosine phosphate. MarR regulates multiple antibiotic resistance mechanisms in Escherichia coli and is rarely found in viruses. No tRNA genes were identified and no lysogeny-related feature genes were detected. However, many similar open reading frames (ORFs) were found in the host genome, which may indicate that Y8A also has a lysogenic stage. Phylogenetic analysis based on the amino acid sequences of whole genomes and comparative genomic analysis indicate that vB_PmaS_Y8A contains a novel genomic architecture similar only to that of Psychrobacter phage pOW20-A, although at a low similarity. vB_PmaS_Y8A represents a new family-level virus cluster with 22 metagenomic assembled viral genomes, here named Minviridae. IMPORTANCE Although Psychrobacter is a well-known and important bacterial genus that is widespread in Antarctic and marine environments, genetic characterization of its phages is still rare. This study describes a novel Psychrobacter phage containing an uncharacterized antibiotic resistance gene and representing a new virus family, Minviridae. The characterization provided here will bolster current understanding of genomes, diversity, evolution, and phage-host interactions in Psychrobacter populations.
    Matched MeSH terms: DNA, Viral/genetics
  4. Tan SC, Ismail MP, Duski DR, Othman NH, Ankathil R
    Biosci Rep, 2018 Apr 27;38(2).
    PMID: 29487170 DOI: 10.1042/BSR20171268
    Information on the prevalence and type distribution of human papillomavirus (HPV) among Malaysian women is currently limited. The present study therefore aimed to provide an updated estimate on the prevalence and type distribution of HPV among Malaysian women with and without cervical cancer. Total DNA was isolated from the cervical cell specimens of 185 histopathologically confirmed cervical cancer patients and 209 cancer-free healthy females who were tested negative in a recent Pap test. Viral-specific DNA was subsequently amplified with biotinylated primers and hybridized to HPV type-specific probes via a proprietary "flow-through hybridization" process for determination of HPV genotype. It was demonstrated that 83.2% of the cervical cancer patients and none (0.0%) of the cancer-free females were positive for HPV infection. Among HPV-positive subjects, 14 different viral genotypes were observed, namely HPV16, 18, 31, 33, 35, 45, 52, 53, 58, 66/68, 73, 81, 82, and 84/26. A total of 91.6% of the HPV-positive subjects had single-type HPV infections and the remaining 8.4% were simultaneously infected by two HPV genotypes. The most common HPV infections found were HPV16 (35.7%), HPV18 (26.0%), HPV58 (9.1%), and HPV33 (7.1%) single-type infections, followed by HPV16 + HPV18 co-infections (5.2%). The study has successfully provided an updated estimate on the prevalence and type distribution of HPV among Malaysian women with and without cervical cancer. These findings could contribute valuable information for appraisal of the impact and cost-effectiveness of prophylactic HPV vaccines in the Malaysian population.
    Matched MeSH terms: DNA, Viral/genetics*
  5. Wang H, Zheng K, Wang M, Ma K, Ren L, Guo R, et al.
    Microbiol Spectr, 2024 Feb 06;12(2):e0336723.
    PMID: 38214523 DOI: 10.1128/spectrum.03367-23
    Shewanella is a prevalent bacterial genus in deep-sea environments including marine sediments, exhibiting diverse metabolic capabilities that indicate its significant contributions to the marine biogeochemical cycles. However, only a few Shewanella phages were isolated and deposited in the NCBI database. In this study, we report the isolation and characterization of a novel Shewanella phage, vB_SbaS_Y11, that infects Shewanella KR11 and was isolated from the sewage in Qingdao, China. Transmission electron microscopy revealed that vB_SbaS_Y11 has an icosahedral head and a long tail. The genome of vB_SbaS_Y11 is a linear, double-stranded DNA with a length of 62,799 bp and a G+C content of 46.9%, encoding 71 putative open reading frames. No tRNA genes or integrase-related feature genes were identified. An uncharacterized anti-CRISPR AcrVA2 gene was detected in its genome. Phylogenetic analysis based on the amino acid sequences of whole genomes and comparative genomic analyses indicate that vB_SbaS_Y11 has a novel genomic architecture and shares low similarity to Pseudomonas virus H66 and Pseudomonas phage F116. vB_SbaS_Y11 represents a potential new family-level virus cluster with eight metagenomic assembled viral genomes named Ranviridae.IMPORTANCEThe Gram-negative Shewanella bacterial genus currently includes about 80 species of mostly aquatic Gammaproteobacteria, which were isolated around the globe in a multitude of environments, such as freshwater, seawater, coastal sediments, and the deepest trenches. Here, we present a Shewanella phage vB_SbaS_Y11 that contains an uncharacterized anti-CRISPR AcrVA2 gene and belongs to a potential virus family, Ranviridae. This study will enhance the knowledge about the genome, diversity, taxonomic classification, and global distribution of Shewanella phage populations.
    Matched MeSH terms: DNA, Viral/genetics
  6. Atchison S, Shilling H, Balgovind P, Machalek DA, Hawkes D, Garland SM, et al.
    J Appl Microbiol, 2021 Nov;131(5):2592-2599.
    PMID: 33942451 DOI: 10.1111/jam.15126
    AIM: Validate the Roche, MagNAPure96 (MP96) nucleic acid extraction platform for Seegene Anyplex II HPV28 (Anyplex28) detection of Human Papillomavirus.

    METHODS AND RESULTS: Comparisons were made for Anyplex28 genotyping from 115 cervical samples extracted on the Hamilton, STARlet and the MP96. Two DNA concentrations were used for the MP96, one matched for sample input to the STARlet and another 5× concentration (laboratory standard). Agreement of HPV detection was 89·8% (κ = 0·798; P = 0·007), with HPV detected in 10 more samples for the MP96. There was a high concordance of detection for any oncogenic HPV genotype (κ = 0·77; P = 0·007) and for any low-risk HPV genotype (κ = 0·85; P = 0·008). DNA extracted at laboratory standard had a lower overall agreement 85·2% (κ = 0·708; P DNA with a higher analytical sensitivity on the Anyplex28.

    SIGNIFICANCE AND IMPACT OF THE STUDY: This analysis supports the use of samples extracted on the MP96 for HPV genotyping using the Anyplex28. Furthermore, an increase in DNA concentration increased analytical sensitivity of the Anyplex28, particularly appropriate for prevalence studies.

    Matched MeSH terms: DNA, Viral/genetics
  7. Low WF, Ngeow YF, Chook JB, Tee KK, Ong SK, Peh SC, et al.
    Expert Rev Mol Med, 2022 Nov 16;25:e11.
    PMID: 36380484 DOI: 10.1017/erm.2022.38
    Hepatitis B virus (HBV) infection led to 66% liver deaths world-wide in year 2015. Thirty-seven per cent of these deaths were the result of chronic hepatitis B (CHB)-associated hepatocellular carcinoma (HCC). Although early diagnosis of HCC improves survival, early detection is rare. Methylation of HBV DNA including covalently closed circular DNA (cccDNA) is more often encountered in HCC cases than those in CHB and cirrhosis. Three typical CpG islands within the HBV genome are the common sites for methylation. The HBV cccDNA methylation affects the viral replication and protein expression in the course of infection and may associate with the disease pathogenesis and HCC development. We review the current findings in HBV DNA methylation that provide insights into its role in HCC diagnosis.
    Matched MeSH terms: DNA, Viral/genetics
  8. Jaapar FN, Parmin NA, Halim NHA, Hashim U, Gopinath SCB, Halim FS, et al.
    Int J Biol Macromol, 2023 Dec 31;253(Pt 2):126745.
    PMID: 37689297 DOI: 10.1016/j.ijbiomac.2023.126745
    Genosensor-based electrodes mediated with nanoparticles (NPs) have tremendously developed in medical diagnosis. Herein, we report a facile, rapid, low cost and highly sensitive biosensing strategy for early detection of HPV 18 using gold-nanoparticles (AuNPs) deposited on micro-IDEs. This study represents surface charge transduction of micro-interdigitated electrodes (micro-IDE) alumina insulated with silica, independent and mini genosensor modified with colloidal gold NPs (AuNPs), and determination of gene hybridization for early detection of cervical cancer. The surface of AuNPs deposited micro-IDE functionalized with optimized 3-aminopropyl-triethoxysilane (APTES) followed by hybridization with deoxyribonucleic acid (DNA) virus to develop DNA genosensor. The results of ssDNA hybridization with the ssDNA target of human papillomavirus (HPV) 18 have affirmed that micro-IDE functionalized with colloidal AuNPs resulted in the lowest detection at 0.529 aM. Based on coefficient regression, micro-IDE functionalized with AuNPs produces better results in the sensitivity test (R2 = 0.99793) than unfunctionalized micro-IDE.
    Matched MeSH terms: DNA, Viral/genetics
  9. Haqshenas G, Molano M, Phillips S, Balgovind P, Garland SM, Hawkes D, et al.
    Arch Pathol Lab Med, 2024 Mar 01;148(3):353-358.
    PMID: 37226838 DOI: 10.5858/arpa.2022-0317-OA
    CONTEXT.—: Detection of human papillomavirus (HPV) in formalin-fixed, paraffin-embedded (FFPE) tissues may identify the cause of lesions and has value for the development of new diagnostic assays and epidemiologic studies. Seegene Anyplex II assays are widely used for HPV screening, but their performance using FFPE samples has not been fully explored.

    OBJECTIVE.—: To validate Anyplex II HPV HR Detection (Anyplex II, Seegene) using FFPE samples.

    DESIGN.—: We used 248 stored DNA extracts from cervical cancer FFPE samples collected during 2005-2015 that tested HPV positive using the RHA kit HPV SPF10-LiPA25, v1 (SPF10, Labo Biomedical Products) HPV genotyping assay, manufacturer-validated for FFPE samples.

    RESULTS.—: Of the selected 248 samples, 243 were used in our analysis. Consistent with SPF10 genotyping results, Anyplex II detected all 12 oncogenic types and had an overall HPV detection rate of 86.4% (210 of 243 samples). Anyplex II and SPF10 showed very high agreement for the detection of the 2 most important oncogenic genotypes: HPV 16 (219 of 226; 96.9%; 95% CI, 93.7-98.75) and HPV 18 (221 of 226; 97.8%; 95% CI, 94.9-99.3).

    CONCLUSIONS.—: Overall results showed that both platforms produced comparable HPV genotyping results, indicating the suitability of Anyplex II for FFPE samples. The Anyplex II assay has the added convenience of being an efficient, single-well semiquantitative polymerase chain reaction assay. Further optimization of Anyplex II may enhance its performance using FFPE samples by improving the detection limit.

    Matched MeSH terms: DNA, Viral/genetics
  10. Yap SF, Wong PW, Chen YC, Rosmawati M
    PMID: 12118437
    A retrospective study was carried out to determine the frequency of the pre-core stop codon mutant virus in a group of chronic hepatitis B carriers: 81 cases were considered [33 hepatits B e antigen (HBe) positive and 48 HBe negative]. All of the HBe positive cases had detectable viral DNA by hybridization analysis; in the case of the HBe negative cases, one third had detectable viral DNA by hybridization analysis and two thirds had HBV DNA detectable by polymerase chain reaction (PCR) amplification. Pre-core stop codon mutant detection was carried out on all specimens using allele-specific oligonucleotide hybridization following PCR amplification of the target sequence. The pre-core mutant was detected in 13/33 (39.4%) of HBe positive cases and in 32/48 (66.7%) of HBe negative cases. Sequence analysis was carried out on 8 of the 16 HBe negative specimens that did not carry the pre-core mutant virus to determine the molecular basis for the HBe minus phenotype in these cases: the 1762/1764 TA paired mutation in the second AT rich region of the core promoter was detected in five cases; a start codon mutation was detected in one case. The predominant mutation resulting in the HBe minus phenotype in our isolates was the 1896A pre-core ("pre-core stop codon") mutation; other mutations responsible for the phenotype included the core promoter paired mutation and pre-core start codon mutation. In view of the high frequency of the pre-core mutant virus, sequence analysis was performed to determine the virus genotype on the basis of the nucleotide sequence of codon 15. The sequences of 21 wild type virus (14 HBe positive and 7 HBe negative cases) were examined: 15 were found to be codon 15 CCT variants (71.4%); the frequency in the HBe positive group was 12/14 (85.7%), while that in the HBe negative group was 3/7 (42.9%). The high frequency of the codon 15 CCT variant in association with the frequent occurrence of the pre-core mutant in our isolates concurs with the results of other studies.
    Matched MeSH terms: DNA, Viral/genetics
  11. Tang KF, Lightner DV
    Dis Aquat Organ, 2011 Feb 22;93(3):191-8.
    PMID: 21516971 DOI: 10.3354/dao02293
    We describe a duplex real-time PCR assay using TaqMan probes for the simultaneous detection of monodon baculovirus (MBV) and hepatopancreatic parvovirus (HPV). Both MBV and HPV are shrimp enteric viruses that infect intestinal and hepatopancreatic epithelial cells. Both viruses can cause significant mortalities and depressed growth in infected larval, postlarval, and early juvenile stages of shrimp, and thus present a risk to commercial aquaculture. In this duplex assay, we combined 2 single real-time PCRs, amplifying MBV and HPV, in a one-tube PCR reaction. The 2 viruses were distinguished by specific fluorescent labels at the 5' end of TaqMan probes: the MBV probe was labeled with dichlorodimethoxyfluorescein (JOE), and the HPV probe was labeled with 6-carboxyfluorescein (FAM). The duplex real-time PCR assay was performed in a multi-channel real-time PCR detection system, and MBV and HPV amplification signals were separately detected by the JOE and FAM channels. This duplex assay was validated to be specific to the target viruses and found to have a detection limit of single copies for each virus. The dynamic range was found to be from 1 to 1 x 10(8) copies per reaction. This assay was further applied to quantify MBV and HPV in samples of infected Penaeus monodon collected from Malaysia, Indonesia, and Thailand. The specificity and sensitivity of this duplex real-time PCR assay offer a valuable tool for routine diagnosis and quantification of MBV and HPV from both wild and farmed shrimp stocks.
    Matched MeSH terms: DNA, Viral/genetics
  12. Cowley JA, Rao M, Coman GJ
    Dis Aquat Organ, 2018 Jul 04;129(2):145-158.
    PMID: 29972375 DOI: 10.3354/dao03243
    Infectious hypodermal and hematopoietic necrosis virus (IHHNV) can cause mass mortalities in western blue shrimp Penaeus stylirostris, runt deformity syndrome in Pacific white shrimp P. vannamei and scalloped abdominal shell deformities in black tiger shrimp P. monodon. In P. monodon, however, PCR-based diagnosis of IHHNV can be complicated by the presence of a chromosome-integrated, non-replicating endogenous viral element (EVE). To facilitate high-throughput screening of P. monodon for IHHNV infection and/or EVE sequences, here we report real-time PCR tests designed to specifically detect IHHNV Lineage I, II and III but not EVE Type A sequences and vice versa. Using 108 dsDNA copies of plasmid (p)DNA controls containing either IHHNV or EVE-Type A sequences, both tests displayed absolute specificity. The IHHNV-q309 PCR reliably detected down to ≤10 copies of pDNA, at which levels a 309F/R PCR amplicon was just detectable, and the presence of an IHHNV-EVE sequence did not significantly impact its sensitivity. The IHHNV-qEVE PCR was similarly sensitive. Testing of batches of P. monodon clinical samples from Vietnam/Malaysia and Australia identified good diagnostic concordance between the IHHNV-q309 and 309F/R PCR tests. As expected for a sequence integrated into host chromosomal DNA, IHHNV-qEVE PCR Ct values were highly uniform among samples from shrimp in which an EVE was present. The highly specific and sensitive IHHNV-q309 and IHHNV-qEVE real-time PCR tests described here should prove useful for selecting broodstock free of IHHNV infection and in maintaining breeding populations of P. monodon specific pathogen free for IHHNV, and if desired, also free of IHHNV-EVE sequences.
    Matched MeSH terms: DNA, Viral/genetics*
  13. Tan CW, Tee HK, Lee MH, Sam IC, Chan YF
    PLoS One, 2016;11(9):e0162771.
    PMID: 27617744 DOI: 10.1371/journal.pone.0162771
    Enterovirus A71 (EV-A71) causes major outbreaks of hand, foot and mouth disease, and is occasionally associated with neurological complications and death in children. Reverse genetics is widely used in the field of virology for functional study of viral genes. For EV-A71, such tools are limited to clones that are transcriptionally controlled by T7/SP6 bacteriophage promoter. This is often time-consuming and expensive. Here, we describe the development of infectious plasmid DNA-based EV-A71 clones, for which EV-A71 genome expression is under transcriptional control by the CMV-intermediate early promoter and SV40 transcriptional-termination signal. Transfection of this EV-A71 infectious DNA produces good virus yield similar to in vitro-transcribed EV-A71 infectious RNA, 6.4 and 5.8 log10PFU/ml, respectively. Infectious plasmid with enhanced green fluorescence protein and Nano luciferase reporter genes also produced good virus titers, with 4.3 and 5.0 log10 PFU/ml, respectively. Another infectious plasmid with both CMV and T7 promoters was also developed for easy manipulation of in vitro transcription or direct plasmid transfection. Transfection with either dual-promoter infectious plasmid DNA or infectious RNA derived from this dual-promoter clone produced infectious viral particles. Incorporation of hepatitis delta virus ribozyme, which yields precise 3' ends of the DNA-launched EV-A71 genomic transcripts, increased infectious viral production. In contrast, the incorporation of hammerhead ribozyme in the DNA-launched EV-A71 resulted in lower virus yield, but improved the virus titers for T7 promoter-derived infectious RNA. This study describes rapid and robust reverse genetic tools for EV-A71.
    Matched MeSH terms: DNA, Viral/genetics*
  14. Balakrishnan KN, Abdullah AA, Bala J, Abba Y, Sarah SA, Jesse FFA, et al.
    Infect Genet Evol, 2017 10;54:81-90.
    PMID: 28642159 DOI: 10.1016/j.meegid.2017.06.020
    BACKGROUND: Rat cytomegalovirus ALL-03 (Malaysian strain) which was isolated from a placenta and uterus of a house rat, Rattus rattus diardii has the ability to cross the placenta and infecting the fetus. To further elucidate the pathogenesis of the Malaysian strain of Rat Cytomegalovirus ALL-03 (RCMV ALL-03), detailed analysis on the viral genome sequence is crucial.

    METHODS: Genome sequencing of RCMV ALL-03 was carried out in order to identify the open reading frame (ORF), homology comparison of ORF with other strains of CMV, phylogenetic analysis, classifying ORF with its corresponding conserved genes, and determination of functional proteins and grouping of gene families in order to obtain fundamental knowledge of the genome.

    RESULTS: The present study revealed a total of 123 Coding DNA sequences (CDS) from RCMV ALL-03 with 37 conserved ORF domains as with all herpesvirus genomes. All the CDS possess similar function with RCMV-England followed by RCMV-Berlin, RCMV-Maastricht, and Human CMV. The phylogenetic analysis of RCMV ALL-03 based on conserving genes of herpes virus showed that the Malaysian RCMV isolate is closest to RCMV-English and RCMV-Berlin strains, with 99% and 97% homology, respectively. Similarly, it also demonstrated an evolutionary relationship between RCMV ALL-03 and other strains of herpesviruses from all the three subfamilies. Interestingly, betaherpesvirus subfamily, which has been shown to be more closely related with gammaherpesviruses as compared to alphaherpesviruses, shares some of the functional ORFs. In addition, the arrangement of gene blocks for RCMV ALL-03, which was conserved among herpesvirus family members was also observed in the RCMV ALL-03 genome.

    CONCLUSION: Genomic analysis of RCMV ALL-03 provided an overall picture of the whole genome organization and it served as a good platform for further understanding on the divergence in the family of Herpesviridae.

    Matched MeSH terms: DNA, Viral/genetics
  15. Duff-Farrier CRA, Mbanzibwa DR, Nanyiti S, Bunawan H, Pablo-Rodriguez JL, Tomlinson KR, et al.
    Mol Biotechnol, 2019 Feb;61(2):93-101.
    PMID: 30484144 DOI: 10.1007/s12033-018-0139-7
    Cassava brown streak disease (CBSD) has major impacts on yield and quality of the tuberous roots of cassava in Eastern and Central Arica. At least two Potyviridae species cause the disease: Cassava brown streak virus (CBSV) and Ugandan cassava brown streak virus (UCBSV). Cloned viral genome sequences known as infectious clones (ICs) have been important in the study of other viruses, both as a means of standardising infectious material and characterising viral gene function. IC construction is often technically challenging for Potyviridae due to sequence instability in E. coli. Here, we evaluate three methods for the construction of infectious clones for CBSD. Whilst a simple IC for in vitro transcription was made for UCBSV isolate 'Kikombe', such an approach failed to deliver full-length clones for CBSV isolates 'Nampula' or 'Tanza', necessitating more complex approaches for their construction. The ICs successfully generated symptomatic infection in the model host N. benthamiana and in the natural host cassava. This shows that whilst generating ICs for CBSV is still a technical challenge, a structured approach, evaluating both in vitro and in planta transcription systems should successfully deliver ICs, allowing further study into the symptomology and virulence factors in this important disease complex.
    Matched MeSH terms: DNA, Viral/genetics
  16. Nakowong P, Chatchawal P, Chaibun T, Boonapatcharoen N, Promptmas C, Buajeeb W, et al.
    Talanta, 2024 Mar 01;269:125495.
    PMID: 38043336 DOI: 10.1016/j.talanta.2023.125495
    Cervical cancer emerges as the third most prevalent types of malignancy among women on a global scale. Cervical cancer is significantly associated with the persistent infection of human papillomavirus (HPV) type 16. The process of diagnosing is crucial in order to prevent the progression of a condition into a malignant state. The early detection of cervical cancer through initial stage screening is of the utmost significance in both the prevention and effective management of this disease. The present detection methodology is dependent on quantitative polymerase chain reaction (qPCR), which necessitates the use of a costly heat cycler instrument. In this study, we report the development of an electrochemical DNA biosensor integrated with an isothermal recombinase polymerase amplification (RPA) reaction for the detection and identification of the high-risk HPV-16 genotype. The electrochemical biosensor exhibited a high degree of specificity and sensitivity, as evidenced by its limit of detection (LOD) of 0.23 copies/μL of HPV-16 DNA. The validity of this electrochemical platform was confirmed through the analysis of 40 cervical tissues samples, and the findings were consistent with those obtained through polymerase chain reaction (PCR) testing. Our straightforward electrochemical detection technology and quick turnaround time at 75 min make the assay suitable for point-of-care testing in low-resource settings.
    Matched MeSH terms: DNA, Viral/genetics
  17. Hage E, Huzly D, Ganzenmueller T, Beck R, Schulz TF, Heim A
    J Infect, 2014 Nov;69(5):490-9.
    PMID: 24975176 DOI: 10.1016/j.jinf.2014.06.015
    Between 2005 and 2013 six severe pneumonia cases (all requiring mechanical ventilation, two fatal outcomes) caused by human adenovirus type 21 (HAdV-B21) were observed in Germany. So far, HAdV-B21 was mainly associated with non-severe upper and lower respiratory tract infections. However, a few highly virulent HAdV types, e.g. HAdV-B14p1, were previously associated with severe, fatal pneumonia. Complete genomic sequences of the German HAdV-B21 pneumonia isolates formed a single phylogenetic cluster with very high sequence identity (≥ 99.897%). Compared to the HAdV-B21 prototype (only 99.319% identity), all isolates had a unique 15 amino acid deletion and a 2 amino acid insertion in the RGD loop of the penton base which may affect binding to the secondary receptor on the host cells. Moreover, a recombinant E4 gene region derived of HAdV-B3 was identified by bootscan analysis. Thus, the highly virulent, pneumotropic HAdV-B21 was denominated as subtype 21a. Surprisingly, there was 99.963% identity with agent Y/SIBU97 (only 13.4 kb available in GenBank of the 35.4 kb genome) which was associated with 10 fatalities due to cardiopulmonary failure in Sarawak, Malaysia, in 1997. In conclusion, a HAdV-B21 subtype (21a) associated with severe pneumonia in Germany was phylogenetically linked to an adenovirus isolated in Malaysia.
    Matched MeSH terms: DNA, Viral/genetics
  18. Gan HM, Sieo CC, Tang SG, Omar AR, Ho YW
    Virol J, 2013;10:308.
    PMID: 24134834 DOI: 10.1186/1743-422X-10-308
    Bacteriophage EC1-UPM is an N4-like bacteriophage which specifically infects Escherichia coli O78:K80, an avian pathogenic strain that causes colibacillosis in poultry. The complete genome sequence of bacteriophage EC1-UPM was analysed and compared with other closely related N4-like phage groups to assess their genetic similarities and differences.
    Matched MeSH terms: DNA, Viral/genetics*
  19. Louisirirotchanakul S, Olinger CM, Arunkaewchaemsri P, Poovorawan Y, Kanoksinsombat C, Thongme C, et al.
    J Med Virol, 2012 Oct;84(10):1541-7.
    PMID: 22930500 DOI: 10.1002/jmv.23363
    Phylogenetic analysis was performed on hepatitis B virus (HBV) strains obtained from 86 hepatitis B surface antigen (HBsAg) positive donors from Thailand originating throughout the country. Based on the S gene, 87.5% of strains were of genotype C while 10.5% were of genotype B, with all genotype B strains obtained from patients originating from the central or the south Thailand. No genotype B strains were found in the north of Thailand. Surprisingly, one patient was infected with a genotype H strain while another patient was infected with a genotype G strain. Complete genome sequencing and recombination analysis identified the latter as being a genotype G and C2 recombinant with the breakpoint around nucleotide position 700. The origin of the genotype G fragment was not identifiable while the genotype C2 fragment most likely came from strains circulating in Laos or Malaysia. The performance of different HBsAg diagnostic kits and HBV nucleic acid amplification technology (NAT) was evaluated. The genotype H and G/C2 recombination did not interfere with HBV detection.
    Matched MeSH terms: DNA, Viral/genetics
  20. Sharifah NA, Seeni A, Nurismah MI, Clarence-Ko CH, Hatta AZ, Ho NP, et al.
    Asian Pac J Cancer Prev, 2009 Apr-Jun;10(2):303-6.
    PMID: 19537900
    Cervical cancer is the second most common female malignancy in Malaysia. Despite advances in treatment, the overall survival for this disease has not changed in the last decade. Infection by certain types of HPV is recognized as a causal and necessary factor for its development. This study was carried out to determine the prevalence of HPV infection in abnormal cervical smears in Malaysian patients using archival cervical smears retrieved from the Cytopathology Unit, Universiti Kebangsaan Malaysia Medical Centre (UKMMC) between the years 1992-1995. DNA was extracted from 38 abnormal smears comprising 25 intraepithelial lesions and 13 cervical carcinomas and 10 normal smears. Amplification of HPV genes was carried out using the polymerase chain reaction (PCR) technique. HPV genotypes were determined using direct sequencing and the results were compared to the database from Genebank. DNA was successfully extracted from all 48 cervical smears. High-risk HPV (HR-HPV) genotypes were detected in 95% of the abnormal smears. Eight high-risk oncogenic types were identified: 16, 18, 31, 51, 52, 56, 58 and 66. All (100%) cervical cancer smears showed presence of HR-HPV compared to 92% of the cervical intraepithelial lesions. Among the eight HR-HPV genotypes identified, HPV 16 and 52 were the commonest (23.7% each) HPV genotypes encountered and among the CIN lesions, HPV 16 (28%) was the most frequent. We conclude that HPV 16 is the most prevalent HPV genotype present in abnormal cervical smears in Malaysian patients, and that the use of archival material to assess the presence of HPV is potentially worthwhile, and can be utilized for longitudinal studies of HPV presence and persistence.
    Matched MeSH terms: DNA, Viral/genetics
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