• Korean Journal of Veterinary Research
• /
• v.44 no.4
• /
• pp.561-569
• /
• 2004

To detect viral agents and isolate porcine circovirus 2 (PCV2), 60 samples of lung and lymph node were collected from 5 to 12 week-old pigs that had showed clinical signs of postweaning multisystemic wasting syndrome (PMWS). Polymerase chain reactions (PCRs) were conducted to identify the viral pathogens including PCV1, PCV2, porcine parvovirus (PPV) and porcine reproductive and respiratory syndrome virus (PRRSV) that have been considered to be the causal agents of PMWS. Among 60 samples, PCV 2 was detected from 57 samples but no PCV 1 was detected. PRRSV and/or PPV were also detected from 27 (47.4%) samples and 1 (1.8%) sample of these 57 PCV 2-positive samples, respectively. Tissue homogenates were inoculated onto PCV-free PK-15 cell monolayers. Seven isolates were confirmed as PCV 2 by multiplex PCR, indirect immunofluorescence assay, and transmissible electron microscopy. These date suggest that PRRSV is a major cofactors causing PMWS in pigs that were infected with PCV2 in Korea.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.56 no.4
• /
• pp.520-525
• /
• 2023

This study aimed to detect Enterococcus spp. strain, a fecal contamination indicator, by PCR assay from short neck clams Venerupis philippinarum in Cheonsu Bay area, Chu Island area and Wonsan Island area, the west coast of Korea, from November 2022 to February 2023 of Enterococcus spp. strain was detected in 19 (79.2%) among 24 samples, and its concentration ranged from <18 to 33,000 MPN (most probable number)/100 g. The 269 isolated Enterococcus spp. strains were identified by PCR assay, and Enterococcus spp. distribution in short neck clams were E. faecium (39.8%), E. faecalis (23.0%), E. hirae (21.9%), E. gallinarum (10.4%), E. casseliflavus (1.5%), E. durans (1.5%) and unidentified strains (1.9%). Thus, E. faecium was the most dominant strain followed by E. faecalis. Overall, these results provide novel insight into the necessity for shellfish sanitation in the sea and could help reduce the fecal contamination risk.

• Research in Plant Disease
• /
• v.17 no.3
• /
• pp.358-363
• /
• 2011

Dapple fruits of plum cv. Oiishiwase (Prunus salicina L.) were occurred at Gyeonggi-do and Gyeongsangbukdo. The symptoms resembled the dapple fruit disease caused by Hop stunt viroid (HSVd). To identify the causal disease agents, RT-PCR was performed with the specific primers of HSVd. RT-PCR analysis showed that HSVd variants (DP1, DP2) were detected from dapple fruits. HSVd detection was also confirmed by the dot blot hybridization using a DIG-probe specific to HSVd. Nucleotide sequences of DP1 and DP2 had the identities of 94-100% with those of other 7 variants of HSVd in Genbank database. DP1 and DP2 were different in two nucleotides of CG and AA at position of 59 and 60, orderly. Based on nucleotide sequences at position of 59 and 60, HSVd variants associated with plum dapple fruits could be divided mainly into three groups as CG, AA and TG.

• Journal of fish pathology
• /
• v.20 no.2
• /
• pp.109-117
• /
• 2007

This study was performed to identity non hemolytic streptococcus from cultured flounder (Paralichthys olivaceus) with Streptococcosis in the Jeju island. The result of BIOLOGTM test was Streptococcus uberis that simility of 0.5 and 98% identified in MicroLogTM system (Release 4.05). Carbohydrate utility pattern was dextrin, N-acetyl-D-glucosamine, arbutin, maltose, maltotriose, D-cellobiose, D-fructose, D-mannose, α-D-glucose, D-mannitol, β-methyl D-glucoside, salicin, sucrose, D-trehalose, pruvatic acid methyl ester, mono-methyl succinate, glycerol. In addition hemolysis test for S. parauberis and were S. iniae hemolysis in BAP (Blood agar plate). Antibiotic test for S. parauberis were Ampicillin, Amoxicillin and Fluoroquinolone sensitivity. Mutiplex PCR assay were detected S. pauberis (718 bp), S. iniae (870 bp) L. garviae (1,100 bp). Dectected S. parauberis (718 bp) were result of 16S rRNA sequence identified with S. parauberis (Gene bank accession number X89967). All isolated S. parauberis that with bouned by one group. The result were S. pauberis that γ-hemolytic chain form cocci and negative reaction of catalase, Multiplex PCR assay were 718 bp amplicon size.

• Journal of Korean Society of Forest Science
• /
• v.94 no.3 s.160
• /
• pp.178-182
• /
• 2005

To identify the seedlings from controlled pollination between one paternal tree and three maternal trees of Japanese red pine, cpSSR markers of the paternally inherited haploid genome were analyzed in two year old 114 seedlings of full sib families. Individual specific DNA fingerprint like haplotypes of the parental trees were determined by PCR with three cpSSR primers. Haplotypes of the 114 seedlings were also identified by PCR with the same primers. On the basis of the comparison of cpDNA haplotypes of the 114 seedlings with those of the parental trees, 14 seedlings revealed to have distinguished haplotypes from those of the paternal tree. It was tentatively concluded that they were generated via pollination with the non-paternal trees. A seedling of Gangwon30 revealing non-paternal haplotype might have been generated via self pollination with the pollens of maternal tree through improper emasculation or contamination during artificial pollination. DNA fingerprint like cpSSR profiles observed in this study could be successfully applied to the various plant forensic analyses, such as identification of siblings of individual trees, asexually reproduced ramets of a specific clone, vegetatively propagated individuals via tissue culture, and pure full sib progenies.

• Korean Journal of Microbiology
• /
• v.48 no.1
• /
• pp.42-47
• /
• 2012

Hydrothermal vents (HTV) provide special environments for evolution of lives independent on solar energy. HTV samples were gained from Tofua arc trench in Tonga, South Pacific. We investigated archaeal diversity enriched using combinations of various electron donors (yeast extract and $H_2$) and electron acceptors [Iron (III), elemental sulfur ($S^0$) and nitrate. PCR amplification was performed to detect archaeal 16S rRNA genes after the cultures were incubated $65^{\circ}C$ and $80^{\circ}C$ for 2 weeks. The cultures showing archaeal growth were transferred using the dilution-to-extinction method. 16S rRNA gene PCR-Denaturing Gradient Gel Electrophoresis was used to identify the enriched archaea in the highest dilutions where archaeal growth was observed. Most of cultured archaea belonged to genus of Thermococcus (T. alcaliphilius, T. litoralis, T. celer, T. barossii, T. thoreducens, T. coalescens) with 98-99% 16S rRNA gene similarities. Interestingly, archaeal growth was observed in the cultures with Iron (III) and nitrate as an electron acceptor. It was supposed that archaea might use the elemental sulfur generated from oxidation of the reducing agent, sulfide. To cultivate diverse archaea excluding Thermococcus, it would be required to use other reducing agents instead of sulfide.

• Parasites, Hosts and Diseases
• /
• v.36 no.2
• /
• pp.69-80
• /
• 1998

Subgenus classification of Acanthcmoeba remains uncertain. Twenty-three reference strains of Acanthnmoeba including 18 (neo)type-strains were subjected for classification at the subgenus level by riboprinting, PCR/RFLP analysis of 185 rRNA gene (rDNA) . On the dendrogram reconstructed on the basis of riboprint analyses, two type- strains (A. astronwxis and A. tubinshi) of morphological group 1 diverged early from the other strains and were quite distinct from each other. Four type-strains of morphological group 3. A. culbertsoni, A. polestinensis, A. healyi were considered taxonomically valid, but A. pustulosn was regarded as an invalid synonym of A. pclestinensis. Strains of morphological group 2 were classified into 6 subgroups. Among them, A. giulni which has an intron in its 185 rDNA was the most divergent from the remaining strains. Acanthcmoebc ccstellanii Castellani, A. quinc Vil3, A. Iugdunensis L3a. A. poIyphage Jones, A. trinngularis SH621, and A. cqstellanii Ma strains belonged to a subgroup, A. castellanii complex. However, A. quinc and A. Lugnunensis were regarded as synonyms of A. ccstellanii. The Chang strain could be regarded as A. hatchetti. Acanthcmoebo nauritaniensis, A. niuionensis, A. paranivionensis could be considered as synonyms of A. rhwsodes. Neff strain was regarded as A. polyphage rather than as A. castellanii. It is likely that riboprinting can be applied for rapid identification of Acnnthcmoebc isolated from the clinical specimens and environments.

• Research in Plant Disease
• /
• v.15 no.3
• /
• pp.170-174
• /
• 2009

In this paper, we report a characterization of Prunus necrotic ringspot virus (PNRSV) isolate. The virus was identified from 'Yumyeong' peach showing mild mosaic on leaves in commercial orchard of 'Umsung', Chungbuk province in Korea. The virus isolate produced ringspot symptom on the inoculated cotyledons and systemic mosaic and malformation on the upper leaves of Cucumis sativus. Systemic mottles were appeared in Chenopodium quinoa. When the buds of the virus infected stem were grafted on the healthy young Prunus persica GF305 seedlings, line pattern with mosaic appeared within 3 months. Isometric virus-like particles were found in parenchyma cells and plasmodesmata of C. sativus leaves inoculated mechanically with the virus. The cDNA fragments of PNRSV coat protein (CP) region, approximately 675bp, were synthesized from genomic RNA extracted from virus-infected leaves by RT-PCR using specific primer pairs. Partial nucleotide sequences of the CP regions were determined and analyzed with the known PNRSV. The CP gene of PNRSVKorea isolates showed 93.9~94.7% similarity to the 4 known PNRSV isolates.

• Weed & Turfgrass Science
• /
• v.4 no.1
• /
• pp.18-25
• /
• 2015

A universal DNA barcoding for agricultural noxious weeds is a powerful technique for species identification without morphological knowledge, by using short sections of DNA from a specific region of the genome. Two standard barcode markers, chloroplast rbcL and matK, and a supplementary nuclear ribosomal Internal Transcribed Spacer (ITS) region were used to examine the effectiveness of the markers for Pooideae barcoding using 163 individuals of 29 taxa across 16 genera of Korean Pooideae. The rbcL and ITS revealed a good level of amplification and sequencing success while matK did not. Barcode gaps were 78.6% for rbcL, 96.2% for matK, and 91.7% for ITS, respectively. Resolving powers were 89.3% for rbcL, 92.3% for matK, and 79.1% for ITS. The matK obtained the best both barcode gap and resolving power. However, it should be considered not to employ matK for Pooideae barcode because of low rate of PCR amplification and sequencing success. As a single DNA marker, rbcL and ITS were reasonable for Pooideae barcode. Barcode gap and resolving power were increased when ITS was incorporated into the rbcL. The barcode sequences were deposited to the National Center for Biotechnology Information (NCBI) database for public use.

• Korean Journal of Microbiology
• /
• v.51 no.2
• /
• pp.169-176
• /
• 2015

The malolactic fermentation (MLF), which is widely used in winemaking, is the conversion of malic acid to lactic acid conducted by the malolactic enzyme (Mle) of lactic acid bacteria. In order to select the strains with MLF among 54 lactic acid bacteria isolated from the traditionally fermented foods, we designed a primer set that specifically targets the conserved regions of the mle gene and then selected four strains that harbor the mle gene of Lactobacillus plantarum. All strains were identified as L. plantarum by analyzing the 16S rRNA sequences, biochemical properties, and the PCR products of the recA gene. From comparison of the mle gene sequences consisting of 1,644 bp, the nucleotide and amino acid sequence of strain JBE60 correspond to 96.7% and 99.5% with those of other three strains, respectively. The strain JBE60 showed the highest resistant against 10% (v/v) ethanol among the strains. The strains lowered the concentration of malic acid to average 43%. Considering the ethanol resistance and conversion of malic acid, the strain JBE60 is considered as a potential starter for the malolactic fermentation.