• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2619-2623
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• 2012

The prevalence of human papillomavirus genotypes differs in various target organs. HPV16 is the most prevalent genotype in the cervix while genotypes 6 and 11 are highly prevalent in skin and aero-digestive tract infections. In this study HPV11 positive specimens were selected from cervix, larynx and lung biopsy tissue to analyze the whole genome by PCR and direct sequencing. Five HPV11 whole genomes were characterized, consisting of two cervical specimens, two laryngeal specimens and one lung specimen. The results showed high homology of HPV11 in these organs. Phylogenetic analysis showed that all HPV11 derived from various organs belonged to the same lineage. Molecular characterization and functional studies can further our understanding of virulence, expression or transmission. Additional studies on functional protein expression at different organ sites will also contribute to our knowledge of HPV infection in various organs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.5
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• pp.725-730
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• 2015

We observed yellow catfish Pelteobagrus fulvidraco fingerlings cultured in land ponds in Korea swimming in a corkscrew spiral pattern while hanging head-up and tail-down at the water surface, before eventually dying. Externally, these fish displayed “hole in the head” disease, pale gills, and hemorrhages in the base of the pectoral and caudal fins; internally they had liver hemorrhages and kidney discoloration. The bacterium Edwardsiella ictaluri (YCK-01 and YCL-01) was identified in the kidneys and livers of diseased fish via phenotypic characteristics and PCR analysis using the ictaluri-specific primers IVS (an intervening sequence) and IRS (the inter-ribosomal spacer). Infectivity challenges by intraperitoneal and immersion routes showed that a representative bacterial strain (YCK) exhibited strong virulence to yellow catfish, with an LD₅₀ of 3.2×10⁴ CFU/fish and 2.5×10⁶ CFU/mL, respectively. This is the first report of E. ictaluri infection in yellow catfish from Korea.

• Journal of Veterinary Clinics
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• v.25 no.4
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• pp.310-313
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• 2008

C. perfringens is the most important enteric clostridial pathogen of animals. C. perfringens type A has been associated with hemorrhagic enteritis in a wide lange of domestic and wild mammals. But all types of C. perfringens can be normal inhabitants of the intestine of most mammals. We have a special case that showed C. perfringens type A infection in a hippopotamus (Hippopotamus amphibius) cub at Seoul Grand Park Zoo. Male, hippopotamus cub died in 3 days after birth. Clinical features of the hippopotamus cub have showed lethargy and anorexia before death. Gross post-mortem findings of the hippopotamus were hemorrhagic enteritis of intestine. Histopathologically, ruminant stomach and intestine showed hemorrhagic lesions and the lumen of the small intestine was filled with mucoid and hemorrhagic fluid. Also, intestine and stomach of hippopotamus were distended with gas and hemorrhagic fluid. C. perfringens was isolated in culture of small intestine and the presence of C. perfringens type A was confirmed by PCR. This case indicated that C. perfringens type A could be considered as a virulence factor responsible for causing death of a newborn hippopotamus.

• Journal of fish pathology
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• v.21 no.1
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• pp.21-27
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• 2008

Mass mortality occurred in mud loaches, Misgurnus mizolepis, cultured in ponds located in Kunsan. External signs of affected fish showed hemorrhage of skin and fins, Internally, pale liver with congestion, enlarged kidney, and spleen and enteritis exhibited. Causative bacteria isolated from liver, spleen, and kidney of the disease fish. In biochemical tests, the isolates were similar with those of the reference strains, A. sobria. The aerolysine gene from the present isolate was amplified PCR with the primer SOBF and SOBB for A. sobria. The isolate was identified as A. sobria on the basis of those tests. In virulence test, the present isolate resulted in the development of clinical signs identical to those in naturally infected fish. The present results conclude that the present isolate is A. sobria and can be a pathogen which causes motile aeromonad septicemia to mud loach.

• Mycobiology
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• v.44 no.1
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• pp.38-47
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• 2016

The ascomycete fungus Mycosphaerella graminicola (synonym Zymoseptoria tritici) is an important pathogen of wheat causing economically significant losses. The primary nutritional mode of this fungus is thought to be hemibiotrophic. This pathogenic lifestyle is associated with an early biotrophic stage of nutrient uptake followed by a necrotrophic stage aided possibly by production of a toxin or reactive oxygen species (ROS). In many other fungi, the genes CREA and AREA are important during the biotrophic stage of infection, while the NOXa gene product is important during necrotrophic growth. To test the hypothesis that these genes are important for pathogenicity of M. graminicola, we employed an over-expression strategy for the selected target genes CREA, AREA, and NOXa, which might function as regulators of nutrient acquisition or ROS generation. Increased expressions of CREA, AREA, and NOXa in M. graminicola were confirmed via quantitative real-time PCR and strains were subsequently assayed for pathogenicity. Among them, the NOXa over-expression strain, NO2, resulted in significantly increased virulence. Moreover, instead of the usual filamentous growth, we observed a predominance of yeast-like growth of NO2 which was correlated with ROS production. Our data indicate that ROS generation via NOXa is important to pathogenicity as well as development in M. graminicola.

• Journal of Microbiology and Biotechnology
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• v.26 no.2
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• pp.263-269
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• 2016

Temperate phages have been suggested to carry virulence factors and other lysogenic conversion genes that play important roles in pathogenicity. In this study, phage TEM123 in wild-type Staphylococcus aureus from food sources was analyzed with respect to its morphology, genome sequence, and antibiotic resistance conversion ability. Phage TEM123 from a mitomycin C-induced lysate of S. aureus was isolated from foods. Morphological analysis under a transmission electron microscope revealed that it belonged to the family Siphoviridae. The genome of phage TEM123 consisted of a double-stranded DNA of 43,786 bp with a G+C content of 34.06%. A bioinformatics analysis of the phage genome identified 43 putative open reading frames (ORFs). ORF1 encoded a protein that was nearly identical to the metallo-β-lactamase enzymes that degrade β-lactam antibiotics. After transduction to S. aureus with phage TEM123, the metallo-β-lactamase gene was confirmed in the transductant by PCR and sequencing analyses. In a β-lactam antibiotic susceptibility test, the transductant was more highly resistant to β-lactam antibiotics than S. aureus S133. Phage TEM123 might play a role in the transfer of β-lactam antibiotic resistance determinants in S. aureus. Therefore, we suggest that the prophage of S. aureus with its exotoxin is a risk factor for food safety in the food chain through lateral gene transfer.

• Journal of Life Science
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• v.32 no.1
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• pp.56-62
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• 2022

This study was investigated to evaluate the potential of Stewartia koreana Nakai as an oral healthcare material. The inhibitory effects of extracts on the biofilm formation and fimbriae genes expression of Porphyromonas gingivalis were determined by minimal inhibitory concentrations (MIC), biofilm biomass staining, SEM, and qRT-PCR analysis. The S. koreana Nakai branch was extracted into 70% ethanol, and bacteriostatic MIC of extracts against P. gingivalis were 0.6 mg/ml. In P. gingivalis cultures treated with 0.2-2.0 mg/ml of extract, biofilm production rate was significantly decreased in a concentration-dependent manner. The morphology of treated and untreated samples was observed by SEM, and cell aggregation and biofilm were only observed in those treated with extract. Subsequently, qRT-PCR analysis showed that the mRNA expression on fimbriae genes fimA and fimB was suppressed in a concentration-dependent manner. Based on these results, it can be suggested that S. koreana branch extract has the potential to be used as naturally derived oral healthcare material because of its bacteriostatic action and inhibition of P. gingivalis biofilm formation.

• Journal of Life Science
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• v.17 no.3 s.83
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• pp.386-395
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• 2007

A total of 27 strains of Vibrio parahaemolyticus (18 strains isolated from Korea and 9 strains from Japan) were serotyped and examined for biochemical characteristics, antimicrobial susceptibility patterns, cytotoxicity assay, thermostable direct hemolysin (TDH) production and molecular epidemiology. Using polymerase chain reaction (PCR) method and DNA probe hybridization method, the strains were tested for toxR, tdh, trh and ORF 8 genes. The V. parahaemolyticus isolated from patients were belonged to 8 different serotypes : O3:K6, O1:K38, O3:K57, O4:K9, O4:Kl2, O4:K68, O5:Kl5 and O6:K46. Urease-positive strain possessed the trh gene, and conversely, urease-negative strains lacked the gene, indicating that urease production by V. parahemolyticus strains strongly correlates with the possession of the trh gene. Most strains showed multiple resistant to more than three antibiotics and the antibiogram could be classified into 6 group (I to VI). All of the O3:K6 strains isolated in South Korea and Japan producted TDH at high levels. The TDH titers ranged between 256 and 2.048, and the average titer was 1009. To distinguish the new and increasingly common V. parahaemolyticus strains from clinical isolates, ORF 8 is a useful genetic marker. After Southern hybridization, the HindIII restriction fragment patterns of the tdh gene were grouped one type, respectively. One type showed two bands one of which was 4.3kb and the other was 11.5kb in size. Variation between the O3:K6 serotype are minor when compared to the differences seen with the non O3:K6 strains. The migration patterns of Not I -digested of the total DNA of the O3:K6 strains were similar, and only slight variations were observed between the serotypes. By contrast, the O3:K6 strains and non O3:K6 had markedly different profiles. In conclusion, Random amplified polymorphic DNA (RAPD) profile using appropriate primers was an effective epidemiological marker.

• Korean Journal of Veterinary Service
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• v.32 no.3
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• pp.227-239
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• 2009

At the present study, it was aimed to detect virulence genes and antimicrobial resistance genes among 102 strains of 12 Salmonella serotypes isolated from pigs and cattle. In polymerase chain reaction (PCR), invA was detected from all strains of Salmonella spp., spvC was detected from Salmonella enterica serotype Enteritidis (S. Enteritidis) (100%), S. Bradenburg (75%), and S. Typhimurium (20.4%). Drug resistance related genes of 12 types were detected from all strains. TEM ($bla_{TEM}$) gene was detected from 51 (92.7%) of 55 $\beta$-lactams (54 ampicillin or 1 amoxicillin) resistance strains. 55 (100%) of 55 chloramphenicol resistance strains, 3 (100%) of 3 gentamicin resistance strains and 5 (100%) of 5 kanamycin resistance strains did contain cml, aadB, and aphA1-Iab, respectively. strB (89.9%), strA (88.4%), aadA2 (84.1%) and aadA1 (72.5%) were detected from 69 streptomycin resistance strains. sulII and dhfrXII were detected from 49 (100%) of 49 sulfamethoxazole/trimethoprim resistance strains, but sulI was not detected. tetA (97.9%) and tetB (21.6%) were detected from 97 tetracycline resistance strains. int gene was detected from 58 (56.9%) of 102 strains. 54 S. Typhimurium of 102 Salmonella spp. were attempted to detect drug resistance genes. TEM was detected from 44 (95.7%) of 46 $\beta$-lactams (45 ampicillin or 1 amoxicillin) resistance strains. cmlA was detected from 51 (100%) of 51 chloramphenicol resistance strains. aadA2 (100%), strA (100%), strB (100%), and aadA1 (79.6%) were detected from 54 streptomycin resistance strains. sulII (100%) and dhfrXII (100%) were detected from 49 sulfamethoxazole/trimethoprim resistance strains. tetA was detected from 54 (100%) of 54 tetracycline resistance strains. int gene was detected from 54 (100%) of 54 strains. The major drug resistance pattern and resistance gene profile were ampicillin, chloramphenicol, streptomycin, sulfamethoxazole/trimethoprim and tetracycline (ACSSuT) and TEM, cmlA, aadA1, aadA2, strA, strB, sulII, dhfrXII, tetA and int, respectively.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.3
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• pp.401-410
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• 2006

Dental caries results from localized demineralization of tooth enamel by acids of bacterial origin produced from the fermentation of dietary sugars. A group of related oral bacteria, collectively known as mutans streptococci, are implicated as the primary etiological agents of human caries. Within this group, Streptococcus mutans has been known as a causative agent for dental caries. As well as acid production yielding the demineralization of tooth enamel, adherence and colonization of S. mutans to the teeth are also important for their virulence Cell-surface fibrillar proteins, which mediate adherence to the salivary pellicle are virulence components of mutans streptococci, and primary candidates for a human caries vaccine. Here we report that the AgI/II gene from S. mutans GS-5 were cloned by PCR amplification of the bacterial chromosomal DNA and the integrity of cloned genes were confirmed by nucleotide sequencing. Sequence analyses showed the sequence alignment of 280 nucleotides between the cloned AgI/II and the reported sequence of S. mutans GS-5 showed the perfect match The cloned genes which signal nucleotide was truncated, were transferred into bacterial expression vector and the recombinant proteins were purified as His-tag fusion proteins In order to generate polyclonal antibodies against the recombinant proteins, AgI/II mr, some $100{\mu}g$ of the proteins was injected into mice three times. It can be used for an effective vaccine production to prevent dental caries caused by pathogenic S. mutans.