• Genomics & Informatics
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• v.21 no.3
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• pp.34.1-34.10
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• 2023

Nosocomial infections, commonly referred to as healthcare-associated infections, are illnesses that patients get while hospitalized and are typically either not yet manifest or may develop. One of the most prevalent nosocomial diseases in hospitalized patients is pneumonia, among the leading causes of mortality and morbidity. Viral, bacterial, and fungal pathogens cause pneumonia. More severe introductions commonly included Staphylococcus aureus, which is at the top of bacterial infections, per World Health Organization reports. The staphylococci, S. aureus, strain RMI-014804, mesophile, on-sporulating, and non-motile bacterium, was isolated from the sputum of a pulmonary patient in Pakistan. Many characteristics of S. aureus strain RMI-014804 have been revealed in this paper, with complete genome sequence and annotation. Our findings indicate that the genome is a single circular 2.82 Mbp long genome with 1,962 protein-coding genes, 15 rRNA, 49 tRNA, 62 pseudogenes, and a GC content of 28.76%. As a result of this genome sequencing analysis, researchers will fully understand the genetic and molecular basis of the virulence of the S. aureus bacteria, which could help prevent the spread of nosocomial infections like pneumonia. Genome analysis of this strain was necessary to identify the specific genes and molecular mechanisms that contribute to its pathogenicity, antibiotic resistance, and genetic diversity, allowing for a more in-depth investigation of its pathogenesis to develop new treatments and preventive measures against infections caused by this bacterium.

• Genomics & Informatics
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• v.20 no.2
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• pp.21.1-21.14
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• 2022

The influenza A viruses have high mutation rates and cause a serious health problem worldwide. Therefore, this study focused on genome characterization of the viruses isolated from Thai patients based on the next-generation sequencing technology. The nasal swabs were collected from patients with influenza-like illness in Thailand during 2017-2018. Then, the influenza A viruses were detected by reverse transcription-quantitative polymerase chain reaction and isolated by MDCK cells. The viral genomes were amplified and sequenced by Illumina MiSeq platform. Whole genome sequences were used for characterization, phylogenetic construction, mutation analysis and nucleotide diversity of the viruses. The result revealed that 90 samples were positive for the viruses including 44 of A/H1N1 and 46 of A/H3N2. Among these, 43 samples were successfully isolated and then the viral genomes of 25 samples were completely amplified. Finally, 17 whole genomes of the viruses (A/H1N1, n=12 and A/H3N2, n=5) were successfully sequenced with an average of 232,578 mapped reads and 1,720 genome coverage per sample. Phylogenetic analysis demonstrated that the A/H1N1 viruses were distinguishable from the recommended vaccine strains. However, the A/H3N2 viruses from this study were closely related to the recommended vaccine strains. The nonsynonymous mutations were found in all genes of both viruses, especially in hemagglutinin (HA) and neuraminidase (NA) genes. The nucleotide diversity analysis revealed negative selection in the PB1, PA, HA, and NA genes of the A/H1N1 viruses. High-throughput data in this study allow for genetic characterization of circulating influenza viruses which would be crucial for preparation against pandemic and epidemic outbreaks in the future.

• Journal of Microbiology
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• v.44 no.5
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• pp.530-536
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• 2006

Bacteriophage P4, a satellite phage of coliphage P2, is a very useful experimental tool for the study of viral capsid assembly and cos-cleavage. For an in vitro cos-cleavage reaction study of the P2-P4 system, new shortened and selectable markers containing P4 derivative plasm ids were designed as a substrate molecules. They were constructed by swapping the non-essential segment of P4 DNA for either the kanamycin resistance (kmr) gene or the ampicillin resistance (apr) gene. The size of the genomes of the resulting markers were 82% (P4 ash8 delRI:: kmr) and 79% (P4 ash8 delRI:: apr) of the wild type P4 genome. To determine the lower limit of genome size that could be packaged into the small P4-size bead, these shortened P4 plasmids were converted to phage particles with infection of the helper phage P2. The conversion of plasmid P4 derivatives to bacteriophage particles was verified by the heat stability test and the burst size determination experiment. CsCl buoyant equilibrium density gradient experiments confirmed not only the genome size of the viable phage form of shortened P4 derivatives, but also their packaging into the small P4-size head. P4 ash8 delRI:: apr turned out to be the smallest P4 genome that can be packaged into P4-sized head.

• Genomics & Informatics
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• v.18 no.1
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• pp.5.1-5.5
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• 2020

Highly pathogenic avian influenza (HPAI) viruses have caused severe respiratory disease and death in poultry and human beings. Although most of the avian influenza viruses (AIVs) are of low pathogenicity and cause mild infections in birds, some subtypes including hemagglutinin H5 and H7 subtype cause HPAI. Therefore, sensitive and accurate subtyping of AIV is important to prepare and prevent for the spread of HPAI. Next-generation sequencing (NGS) can analyze the full-length sequence information of entire AIV genome at once, so this technology is becoming a more common in detecting AIVs and predicting subtypes. However, an analysis pipeline of NGS-based AIV sequencing data, including AIV subtyping, has not yet been established. Here, in order to support the pre-processing of NGS data and its interpretation, we developed a user-friendly tool, named prediction of avian influenza virus subtype (PAIVS). PAIVS has multiple functions that support the pre-processing of NGS data, reference-guided AIV subtyping, de novo assembly, variant calling and identifying the closest full-length sequences by BLAST, and provide the graphical summary to the end users.

• Journal of Microbiology and Biotechnology
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• v.10 no.6
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• pp.823-828
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• 2000

The complete nucleotide sequence of hepatitis B virus DNA isolated from Korean patient serum was determined and characterized, and its phylogenetic relation was then investigated. The viral genome was 3,215 base pairs long and included four well known open reading frames (i.e. surface antigens, core antigens, X protein and DNA polymerase). The sequence of the surface antigen showed that the HBV genome under investigation, designated HBV 315, was characteristic of subtype adr. A phylogenetic analysis using the total genome sequence revealed that HBV315 was grouped into genomic group C together with isolates from Japan, China, Thailand, Polynesia, and New Caledonia. The mean percent similarity between HBV315 and other HBV isolates in genomic group C was 97.25%, and that with other genomic groups ranged from 86.16% to 91.25%. The predicted amino acid sequences of HBV315 were compared with two closely related subtype adr isolates, M38636 and D12980. The results showed that the X gene product was identical in the three strains, while there were significant amino acid sequence differences between HBV315 and M38636 in the Pre-S1 and Pre-S2 regions.

• Korean Journal Plant Pathology
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• v.10 no.3
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• pp.228-234
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• 1994

Genomic RNA was extracted from Cy strain of odontoglossum ringspot tobamovirus (ORSV-Cy) isolated from infected leaves of tobacco cv. Samsun. Size of the genomic RNA was about 6.6 kb in length. The genomic RNA was fractionated using Sephadex G-50 column chromatography into 2 fractions. They were polyadenylated at their 3'-end using E. coli poly(A) polymerase. Polyadenylated viral RNA was recovered by oligo (dT) primer adapter containing NotI restriction site and Moloney murine leukemia virus SuperScript reverse transcriptase (RNase H-). Second-strand cDNA was synthesized by using E. coli DNA ligase, E. coli DNA polymerase I and E. coli RNase H. Recombinant plasmids containing cDNAs for ORSV-Cy RNA ranged from about 800 bp to 3,000 bp. Among the selected 238 recombinants, pORCY-124 clone was the largest one covering 3'-terminal half of the viral RNA. This clone contained two restriction sites for EcoRI and XbaI and one site for AccI, AvaI, BglII, BstXI, HindIII, PstI, and TthIII 1. respectively. The clone contained partial viral replicase, a full-length movement protein and a complete coat protein genes followed by a 3' untranslated region of 414 nucleotides based on restriction mapping and nucleotide sequencing analyses. Clones pORCY-028, -068, -072, -187 and -224 were overlapped with the pORCY-124. Clones pORCY-014 and -095 covered 5' half upstream from the middle region of the viral RNA, which was estimated based on restriction mapping and partial sequence analysis. Constructed cDNA library covered more than 90% of the viral genome.

• The Journal of Korean Society of Virology
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• v.29 no.2
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• pp.65-74
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• 1999

Reovirus was found to inhabit both the respiratory and the enteric tract of human and animals. The genome of reovirus comprises 10 segments of double-stranded RNA, total size 24 kbp. Nine strains of reovirus were isolated from human and field mice in Korea. Aseptically collected sera from human and lung tissues from field mice were used for virus isolation. For serotype determination, hemagglutination inhibition test was used, and three strains were confirmed to type 2 and six strains to type 3. To determine the genomic diversity and molecular phylogeny of reoviruses isolated in Korea, part of S4 genomic segment of reovirus was enzymatically amplified and directly sequenced. In nucleotide level, Apo98-35 strain showed 15.4%, 19.3%, and 14.4% differences compared to type 1 (T1L, Lang), type 2 (T2J), and type 3 reference strains, respectively. In amino acid level, Apo98-35 strain showed 10.5%, 13.7%, and 9.5% differences compared to type 1, type 2, and type 3 reference strains, respectively. Using the maximum parsimony method based on 285 bp spaning region of the S4 genomic segment, phylogenetic analysis indicated that Apo98-35 from Korea formed different phylogenetic branch. Our data obtained by sequence and phylogenetic analyses of reoviruses are consistent with the distinct geographically dependent evolution of reoviruses in Korea.

• Research in Plant Disease
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• v.11 no.2
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• pp.98-105
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• 2005

All viruses have few genes relative to their hosts. Viruses, thus, utilize many host factors for efficient viral replication in host cell. Virus-host interactions are crucial determinations of host range, replication, and pathology. Host factors participate in most steps of positive-strand RNA virus infection, including entry, viral gene expression, virion assembly, and release. Recent data show that host factors play important roles in assembling the viral RNA replication complex, selecting and recruiting viral RNA replication templates, activating the viral complex for RNA synthesis, and the other steps. These virus-host interactions may contribute to the host specificity and/or pathology. Positive-strand RNA viruses encompass over two-thirds of all virus genera and include numerous pathogens. This review focuses on the importance of host factors involved in positive strand plant RNA virus genome replication.

• Journal of Microbiology
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• v.45 no.3
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• pp.187-192
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• 2007

REOviruses (Respiratory Enteric Orphan viruses) are ubiquitous, non-enveloped viruses containing 10 segments of double-stranded RNA (dsRNA) as their genome. They are common isolates of the respiratory and gastrointestinal tract of humans but are not associated with severe disease and are therefore considered relatively benign. An intriguing characteristic of reovirus is its innate oncolytic potential, which is linked to the transformed state of the cell. When immortalized cells are transfected in vitro with activated oncogenes such as Ras, Sos, v-erbB, or c-myc, they became susceptible to reovirus infection and subsequent cellular lysis, indicating that oncogene signaling pathways are exploited by reovirus. This observation has led to the use of the virus in clinical trials as an anti-cancer agent against oncogenic tumors. In addition to the exploitation of oncogene signaling, reovirus may further utilize host immune responses to enhance its antitumor activity in vivo due to its innate interferon induction ability. Reovirus is, however, not entirely benign to immunocompromised animal models. Reovirus causes so-called "black feet syndrome" in immunodeficient mice and can also harm neonatal animals. Because cancer patients often undergo immunosuppression due to heavy chemo/radiation-treatments or advanced tumor progression, this pathogenic response may be a hurdle in virus-based anticancer therapies. However, a genetically attenuated reovirus variant derived from persistent reovirus infection of cells in vitro is able to exert potent anti-tumor activity with significantly reduced viral pathogenesis in immunocompromised animals. Importantly, in this instance the attenuated, reovirus maintains its oncolytic potential while significantly reducing viral pathogenesis in vivo.

• YAKHAK HOEJI
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• v.50 no.2
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• pp.93-98
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• 2006

Human foamy virus (HFV) integrase mediates integration of viral c-DNA into cellular DNA. In this process, HFV prointegration complex (PIC) in which integrase is a key component moves to nuclei of the infected cells and leads to integration of viral DNA to the cellular genome, which is essential in viral life cycle. In general nuclear localization signals (NLS) have been suggested to be involved in localizing retroviral PIC to nuclei, but the mechanisms for nuclear localization of the HFV PIC remains unclear. To functionally identify the NLS of HFV integrase, various subdomains of the protein were expressed as GFP fusions and their subcellular locations were analyzed with confocal laser scanning microscopy. Wild type HFV integrase was karyophilic by targeting the fusion protein to nuclei of the COS-1 and 293T cells. Our results showed that strong NLS of HFV integrase was mapped to the C-terminal regions. In addition the karyophilic properties of N-terminal and central regions are not individually strong enough to direct localization of the fusion proteins to nuclei, but their cooperative activity for nuclear import was confirmed.