• Journal of Species Research
• /
• v.10 no.1
• /
• pp.1-11
• /
• 2021

Evidence highlighting the importance of gut microbiota in biodiversity conservation is growing; however, gut bacteria in South Korean wildlife have not been well identified. Using a culture-dependent isolation method, we identified the gut bacteria from Korean aquatic wildlife: the gazami crab (Portunus trituberculatus), Korean striped bitterling (Acheilognathus yamatsutae), oily bitterling (Acheilognathus koreensis), leopard mandarin fish (Siniperca scherzeri), Korean dark chub (Zacco koreanus), diving beetle (Cybister lewisianus), spotted steed (Abbottina springeri), and Korean spotted sleeper (Odontobutis obscura interrupta). We identified 18 strains previously unrecorded in South Korea by comparing 16S rRNA gene sequences of isolates against the EzBioCloud and National Institute of Biological Resources(NIBR) databases. The isolated strains belong to the phyla Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria. We also assessed for phylogenetic relatedness, Gram-stain reaction, colony and cell morphology, and biochemical characteristics. Basic information and 16S rRNA gene sequences of the isolates were registered in NIBR, and NIBR accession numbers are provided.

• Proceedings of the PSK Conference
• /
• 2001.04a
• /
• pp.214.3-215
• /
• 2001

• Proceedings of the Korean Society of Plant Pathology Conference
• /
• 2003.10a
• /
• pp.23-23
• /
• 2003

Chestnut blight, caused by Cryphonectria parasitica, is the most destructive disease of American and European chestnut trees. A total of 672 C prasitica was isolated from blight lesion on chestnut twigs, which were collected from major chestnut plantations all over Korea in 1999. Isolation rates were over 30% in Kyunggj-, Kyongnam-, and Chonnam-do. The highest isolation rate was 37.4% and recorded in Kyongnam-do. On the other hand, Chonbuk-do had the lowest isolation rate as 13.5%. In grouping of C parasitica by colony shape and color, yellow colony with irregular margin were the most dominant colony type with a frequency of 65.2%. When the 672 isolates were inoculated on the chestnut twigs, 380 isolates (56.5%) caused lesions larger than the standard virulent isolate EP155-2, while 158 isolates (23.4%) caused smaller lesions than the standard hypovirulent isolate UEP-1. In Bavendamm test that determines phenol oxidase activity, 97.1% of all the isolates resulted the same or darker discoloration than EP155-2, and only 12.2% resulted the same or lighter discoloration than UEP-1. In the vegetative compatibility (VC) tests, total 670 isolates were divided into 121 VC groups (VCGs). Kyongnam-, Chonnam-, and Chungnam-do, the three principal chestnut plantation area, had 49, 33, and 27 VCGs, respectively. Among the VCGs, the biggest VCG, KR-VC104, was composed of 164 isolates and the second biggest VCG had 62 isolates. But, 64 of 121 VCGs consisted of sole member. More than 65.8% of KR-VC104, was isolated from the three provinces, Kyongnam-, Kangwon-, and Chungbuk-do. In KR-VC104, 62.8%, 59.1%, and 85.9% of the isolates looked like virulent in colony type, pathogenicity test, and Bavendamm test. In ds-RNA detection tests using cellulose chromatography, 77 of total 650 isolates were ds-RNA positive and detected ds-RNA segments were approximately 12kb, 3kb, 2.7kb, 2kb, and 1.8kb in size. Among the 77 isolates, 46 isolates had 12kb and 25 isolates had 12kb and 2.7kb. Other 6 Isolates had small ds-RNA segments. Kyongnam-, Chonnam-, and Chungnam-do had 43, 16, and 5 ds-RNA positive isolates, respectively. Among the 121 VCGs, only 29 VCGs had ds-RNA positive isolates.(중략)

• Journal of Life Science
• /
• v.12 no.2
• /
• pp.158-163
• /
• 2002

For axenic isolation of the cyanobacterium Microcystis aeruginosa, water bloom at the Mulgum station from the Nakdong River was pretreated by shaking with distilled water. Removal of bacteria was accomplished using antibiotics (150 $\mu$g/$m\ell$ ampicillin and 25 $\mu$g/$m\ell$ neomycin) and colonizing on CB solid medium prepared from 0.7% agarose at 3$0^{\circ}C$ under 40 $\mu$ mol m$^{-2}$ s$^{-1}$ light. Among 26 strains of the Microcystis species, only three strains were axenically established. The three strains were examined by PCR-amplified 16S rRNA gene and 16S rRNA sequencing. The similarities were 99.5 ~100% with M. aeruginosa AF 139292.

• Journal of Microbiology and Biotechnology
• /
• v.19 no.7
• /
• pp.647-650
• /
• 2009

Using 200 porcine colon tissues, the efficiencies of three isolation methods of Campylobacter from porcine intestines were compared: Method 1, direct streaking of colon mucosa; Method 2, direct inoculation of intestinal contents with a swab; Method 3, inoculation of pre-enriched medium. A total of 460 Campylobacter isolates were obtained from 178 samples (89%) by direct streaking of colon mucosa, 142 samples (71%) by direct streaking of a swab, and 94 samples (47%) by pre-enrichment of intestinal contents in Preston broth. Direct streaking of colon mucosa was superior to the other two isolation methods, in terms of rapidity and higher efficiency. When isolates were identified with various biochemical tests and PCRs specific to 16s rRNA, mapA, and ceuE, C. coli was the predominant species (87%) in porcine, whereas the rest of the isolates were identified as C. lanienae.

• Journal of Life Science
• /
• v.7 no.3
• /
• pp.167-171
• /
• 1997

As an initial effort to elucidate RNA: protein binding in a way to regulate translation initiation and phosphorylation, a cDNA encoding a double-stranded RNA binding factor (RBFII)was isolated from Hela ZAPII cDNA library by affinity screening using [$\alpha$$^{-32}$P] UMP-labeled HIV Rev-responsive element(RRE) RNA. The nucleotide sequence of RBF (or TRBP) cDNA except the 5’end. At the 5’end, This common ORF was fused in-frame to N-terminal residues of Lac-Z through a unique 138 nt sequence encoding 46residues in the case of RBFII and a 63 nt sequence encoding 21 residuces in the case of RBFI. The context of ATG appearing first in the sequences suggests that both these cDNA inserts are incomplete at the 5’end.

• Microbiology and Biotechnology Letters
• /
• v.50 no.3
• /
• pp.422-429
• /
• 2022

The hepatitis C virus (HCV) genome contains a positive-sense single-stranded RNA molecule, and it is classified into 8 genotypes and 87 subtypes. Globally, over 350,000 people die from liver cirrhosis and hepatocellular carcinoma caused by HCV each year. Here, the genotype distribution of HCV was estimated in the population in Cheonan, Korea using Sanger sequencing. In addition, the correlation between HCV RNA level and genotype was assessed using real-time polymerase chain reaction (PCR); similarly, the correlation of HCV RNA level with isolation year (2007-2016) was determined using 463 consecutive serum samples obtained from patients at Dankook University Hospital, Cheonan, Korea. In 2007, genotype 1b (54.2%) was predominant, followed by genotypes 2a (41.7%), 1a (2.1%) and 3a (2.1%); whereas in 2016, the predominant genotype was 2a (49.0%), followed by genotypes 1b (46.9%), 3b (2%), and 4a (2%). Neither age nor sex was correlated with HCV genotype. Furthermore, the mean HCV RNA level decreased significantly from 2012 to 2016 (p < 0.05). However, no significant correlations between genotype and HCV RNA level were found. Overall, the findings revealed that genotypes 2a and 1b were the most common in Cheonan, and the prevalence of HCV genotype 1b tended to decrease over the past decade.

• Korean Journal of Microbiology
• /
• v.44 no.4
• /
• pp.293-298
• /
• 2008

HCV is transmitted via various plasma derived products. Current methods to detect hepatitis C virus (HCV) are based on its antibody detection in the donated blood and plasma. Viral contamination can potentially escape such detection during the window period of infection, when no antibody is present or the level of antibody is too low to detect. It is trying to application of nucleic acid amplification tests (NAT) for the direct detection of HCV. The objective of this study was to develop a reliable NAT for the HCV RNA detection from plasma-derived products. The most useful primers was selected for NAT among 5 sets of primers. We have also found that QIAamp viral RNA isolation kit was the most efficient for HCV RNA isolation. The highest sensitivity and specificity was appeared in $48^{\circ}C$ annealing temperature and 30 pmol of primers. With a spiking of HCV to albumin, immunoglobulins and coagulation factors, NAT can detect up to 100 IU/ml. Meanwhile, COBAS amplicor HCV 2.0 afforded a lower sensitivity in high concentrated intramuscular immunoglobulins to below 500 IU/ml. Our results suggested that NAT appears to be a highly sensitive and specific method for HCV RNA detection in plasma-derived products.

• Journal of Gastric Cancer
• /
• v.3 no.3
• /
• pp.128-133
• /
• 2003

Purpose: The benefits of the 'no-touch' isolation techniquethat is usually performed to prevent the circulation of tumor cells are not evident. The aim of this study was to determine whether the no-touch isolation technique for treating gastrointestinal cancers could prevent the circulation of tumor cells detected by reverse transcriptase polymerase chain reaction (RT-PCR). Matrials and Methods: By using RT-PCR to amplify mRNAs for two specific epithelial markers, carcinoembryonic antigen (CEA) and cytokeratin 20 (CK-20), we examined 34 gastric cancer patients who had been histologically diagnosed and 22 patients had undergone serosal and peritoneal brushing. Results: In 10 ($29.4\%$) of the 34 gastric cancer patients, we detected CK20 mRNA before manipulation, and in 17 ($51.5\%$) of those patients, after we detected it. The density of the CK20 mRNA band was increased in 11 cases ($33.3\%$) and the density was decreased in 2 cases ($6.1\%$). In 16 ($48.5\%$) of the 34 gastric cancer patients, we detected CEA mRNA before manipulation, and in 17 ($51.5\%$) patients after we detected it. The density of the CEA mRNA band was increased in 8 cases ($24.2\%$) and decreased in 3 cases ($9.1\%$). Conclusion: These result suggest that the ' no-touch isolation technique ' might be useful when operating on advanced gastric cancer patients and that serosal or Douglas pouch brushing can be used to determine the status of micrometastasis.

• Korean Journal of Veterinary Service
• /
• v.32 no.4
• /
• pp.335-341
• /
• 2009

Canine brucellosis produce abortions and infertility in dogs and is currently diagnosed by serological methods such as rapid slide agglutination test with 2-mercaptoethanol (2-ME RSAT) and immunochromatographic assay (ICA). Bacterial isolation is considered gold standard for Brucella diagnosis and the polymerase chain reaction (PCR) is an alternative method to bacterial isolation. A total of 36 whole blood samples were collected from dogs reared in area of Chuncheon and were subjected to serology (2-ME RSAT and ICA for B. canis, Rose Bengal test and C-ELISA for B. abortus), blood culture and 3 types of PCRs (BSCP31, 16s rRNA, and OMP-2). All blood samples were negative by serology and blood cultures. The BCSP31 and the OMP-2 PCR detected 5 samples were positive whereas the 16S rRNA PCR detected all samples were negative as serological methods and blood culture did. From the results observed in the present study, we conclude that 16S rRNA PCR could be used for direct PCR for canine blood samples.