• Korean Journal of Veterinary Service
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• v.42 no.1
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• pp.17-24
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• 2019

The aim of this study was to investigate the prevalence and characterization of plasmid-mediated quinolone resistance (PMQR) gene in 79 Enterobacteriaceae isolated from dogs and cats. Of 79 isolates, PMQR genes were found in 10 (12.7%) isolates, including aac(6')-lb-cr, qnrB, qnrS and qnrA detected alone or in combination in 8 (10.1%), 4 (5.1%), 2 (2.5%) and 1 (1.3%) isolates, respectively. Interestingly, two qnrS genes were detected in nalidixic acid and ciprofloxacin susceptible isolates. Extended-spectrum ${\beta}$-lactamase (ESBL) was detected in 90% (9 isolates) of PMQR positives isolates. Among ESBL genes, CTX-M, TEM and SHV were detected in 9, 8 and 3 isolates, respectively. Almost all PMQR genes were detected in co-existence with ESBL genes. All PMQR positives isolates were multidrug resistance (i.e. resistant to five or more antibiotics). qepA, OXA and CMY-2 genes were not found. The six transconjugants were obtained by conjugation experiment. The aac(6')-lb-cr, qnrB and qnrS were co-transferred with CTX-M, TEM and/or SHV, whereas qnrA was not observed among transconugants. This is the first report of the presence of aac(6')-lb-cr and qnrA gene among Enterobacteriaceae isolates from dogs in Korea. The prudent use of antimicrobials and continuous monitoring for companion animals are required.

• Mycobiology
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• v.51 no.6
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• pp.393-400
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• 2023

During a disease survey in October 2019, leaf spot symptoms with a yellow halo were observed on Korean angelica (Anglica gigas) plants grown in fields in Pyeongchang, Gangwon Province, Korea. Incidence of diseased leaves of the plants in the investigated fields ranged from 10% to 60%. Morphological and cultural characteristics of two single-spore isolates from the leaf lesions indicated that they belonged to the genus Didymella. Molecular phylogenetic analyses using combined sequences of LSU, ITS, TUB2, and RPB2 regions showed distinct clustering of the isolates from other Didymella species. In addition, the morphological and cultural characteristics of the isolates were somewhat different from those of closely related Didymella spp. Therefore, the novelty of the isolates was proved based on the investigations. Pathogenicity of the novel Didymella species isolates was confirmed on leaves of Korean angelica plants via artificial inoculation. This study reveals that Didymella gigantis sp. nov. causes leaf spot in Korean angelica.

• The Korean Journal of Mycology
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• v.26 no.4 s.87
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• pp.478-486
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• 1998

The isolates of Rhizopus collected from Korean traditional fermented food meju and nuruk, were compared with the well known species of Rhizopus donated. The isolates of Rhizopus were identified with the numerical analyses calculated from RAPD-DNA bands, and confirmed with the microscopic observations of morphological features on PDA. The isolates of R. oryzae purchased were segregated through the results of RAPD or the morphological features. The species of R. nigricans, known as an illegitimate species, were different from those of R. stolonife and it is estimated that they are species of Rhizopus, again. According to microscopic observations and the result of RAPD, Some isolates of R. oryzae purchased belong to R. nigricans and are completely different from R. oryzae in their growth. The isolates of R. nigricans included with several isolates of R. oryzae identified for the different phenotypes and were heterogenous. The isolate of R. oligosporus were speculated to be different from morphological features of Rhizopus, but to be similar to the species of Absidia on the apophysis of sporangium. Its sporangiophore or mycelium was observed to be dark black, but the sporangia were not in those of R. oligosporus. The isolates collected from Korean traditional nuruk showed genetic diversity, and also considered to be different tastes in Korean rice wines.

• Korean Journal of Veterinary Service
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• v.32 no.1
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• pp.1-10
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• 2009

In order to obtain the genetic information of the Korean isolates of porcine circovirus 2 (PCV2), complete genomes of five isolates from Korean PCVD weaned pigs with wasting syndromes were sequenced and compared with those of other published PCV2 isolates. Of the five PCV2 isolates, four (1767 nucleotides) were classified into PCV2b, and one (1,768 nucleotides) was PCV2a. Moreover, it appeared that PCV2b is now the dominant genotype circulating in Korea herds. Total complete genomes of four PCV2b isolates shared $99.1{\sim}99.4%$ nucleotide sequence homology each other, and were only $95.4{\sim}96.2%$ similar to one PCV2a isolate. ORF2 genome of four PCV2b isolates shared over 99% nucleotide sequence and deduced amino acid sequence identity to each other. Nevertheless, those were much divergent with the PCV2a isolate of this study and ranged from $92.3{\sim}92.7%$ nucleotide homology and $91.9{\sim}92.3%$ deduced amino acid sequence homology, respectively. The amino acid sequence alignments of the putative capsid protein identified three major regions of amino acid heterogeneity at residues $59{\sim}91$, $121{\sim}136$ and $190{\sim}210$. Two of those correspond with dominant immunoreactive areas. Phylogenetic analysis based on the complete genome of PCV2 isolates showed that four PCV2b isolates of this study existed the closest relationship with European strains (Netherland, UK and France). One PCV2a isolate was closely related to Japan and North America strains.

• Korean Journal Plant Pathology
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• v.11 no.4
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• pp.330-337
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• 1995

Forty-six isolates of Fusarium oxysporum collected from infected tomato plants and soils in greenhouses in Sedo, Chungnam and Angang, Kyeongbuk and 8 isolates of F. oxysporum f. sp. lycopersici from Japan and USA were used to determine vegetative compatibility groups (VCGs). Vegetative comaptibility was assessed on the basis of heterokaryon formation among nitrate nonutilizing mutants. All Korean isolates of F. oxysporum f. sp. lycopersici used in this study belonged to the same type of VCG (003) regardless of their geographic origin, cultivar and race, but they were incompatible with the foreign isolates of VCG 0030, 0031, 0032 and 0033. Based on the results, the Korean isolates of F. oxysporum f. sp. lycopersici were classified as a new VCG 003.

• Parasites, Hosts and Diseases
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• v.42 no.3
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• pp.145-148
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• 2004

We compared the DNA sequence difference of isolates of Clonorchis sinensis from one Korean (Kimhae) and two Chinese areas (Guangxi and Shenyang), The sequences of nuclear rDNA (18S, internal transcribed spacer 1 and 2: ITS1 and ITS2) and mitochondrial DNA (cytochrome c oxidase subunit 1: cox1) were compared. A very few intraspecific nucleotide substitution of the 18S, ITS1, ITS2 and cox1 was found among three isolates of C. sinensis and a few nucleotide insertion and deletion of ITS1 were detected. The 18S, ITS1, ITS2 and cox1 sequences were highly conserved among three isolates. These findings indicated that the Korean and two Chinese isolates are similar at the DNA sequence level.

• The Korean Journal of Pesticide Science
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• v.19 no.1
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• pp.71-79
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• 2015

In order to investigating the effects of antifungal activity of intestinal bacteria obtained from insect, it was identified these bacteria isolated from the gut. In this result, total 49 isolates of intestinal bacteria were identified from 10 kinds of insect species. It was that 4 isolates including Cedecea sp. from Nesidiocoris tenuis, 3 isolates including Enterobacter sp. from Odontotaenius disjunctus, 4 isolates including Acinetobacter sp. from Reticulitermes speratus, 4 isolates including Clavibacter sp. from Riptortus clavatus, 11 isolates including Bacillus sp. from Lema decempunctata, 3 isolates including Enterococcus sp. from Henosepilachna vigintioctopunctata 2 isolates including Staphylococccus sp. from Harmonia axyridis, 5 isolates including Enterobacter asburiae from Popillia mutans, 7 isolates including Aeromonas sp. from Hydrophilus acuminatus, and 7 isolates including Brucella sp. from Anomala octiescostata. In order to investigating antifungal activity against plant-pathogenic fungi, Altanaria solani, Colletotrichum gloeosporioides, Botrytis cinerea, Fusarium oxysporum, Phytophthora capsici, Rhizoctonia solani and Selerotinia sclerotiorum were dual cultured with each 49 gut enterobacteriaceae. As these results showed that many isolates have the antifungal activities including 26 isolates against A. solani, 6 isolates against B. cinerea, 13 isolates against C. gloeosporioides, 11 isolates against F. oxysporum, 17 isolates P. capsici, 2 isolates against R. solani and 2 isolates against S. sclerotiorum. Pseudomonas aeruginosa was showed strong antifungal activity against all of tested plant pathogens. It might be taken a potential for application against plant-pathogenic fungi with useful control agent.

• Korean Journal of Microbiology
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• v.20 no.2
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• pp.73-79
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• 1982

Among 131 isolates of Strptomyces obtained from ginseng cultivating soil, the two isolates ST59 and ST129 showing high antagonistic activity to Fusarium solani(Mart.) Appel & We. causing ginseng root rot were identified. The two isolates were identified Streptomyces alboniger Porter, et al. and Strptomyces reseolilacinus Pridham, et al., respectively, based on mrophology, cultural, and physiological characteristics on various culture media. Spore chains of ST59 and ST129 were flexuous(RF) and coiled(S). Spore surfaces of two isolates were all smooth. Aerial mass color of ST59 was white series and ST129 red series.

• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1286-1298
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• 2005

The genus Paenibacillus is a new group of bacilli separated from the genus Bacillus, and most of species have been isolated from soil. In the present study, we collected 450 spore-forming bacilli from the roots of winter crops, such as barley, wheat, onion, green onion, and Chinese cabbage, which were cultivated in the southern part of Korea. Among these 450 isolates, 104 Paenibacillus-like isolates were selected, based on their colony shape, odor, color, and endospore morphology, and 41 isolates were then finally identified as Paenibacillus spp. by 16S rDNA sequencing. Among the 41 Paenibacillus isolates, 23 were classified as P. polymyxa, a type species of the genus Paenibacillus, based on comparison of the 16S rDNA sequences with those of 32 type strains of the genus Paenibacillus from the GenBank database. Thirty-five isolates among the 41 Paenibacillus isolates exhibited antagonistic activity towards plant fungal and bacterial pathogens, whereas 24 isolates had a significant growth-enhancing effect on cucumber seedlings, when applied to the seeds. An assessment of the root-colonization capacity under gnotobiotic conditions revealed that all 41 isolates were able to colonize cucumber roots without any significant difference. Twenty-one of the Paenibacillus isolates were shown to contain the nifH gene, which is an indicator of $N_{2}$ fixation. However, the other 20 isolates, including the reference strain E681, did not incorporate the nifH gene. To investigate the diversity of the isolates, a BOX-PCR was performed, and the resulting electrophoresis patterns allowed the 41 Paenibacillus isolates to be divided into three groups (Groups A, B, and C). One group included Paenibacillus strains isolated mainly from barley or wheat, whereas the other two groups contained strains isolated from diverse plant samples. Accordingly, the present results showed that the Paenibacillus isolates collected from the rhizosphere of winter crops were diverse in their biological and genetic characteristics, and they are good candidates for further application studies.

• Journal of Veterinary Clinics
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• v.20 no.3
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• pp.302-307
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• 2003

Although, in human medicine, strains of methicillin-resistant staphylococi have become the most important causative agents of nosocomial infections, studies on the small animals are very. limited. The aim of this study was to determine mecA gene and susceptibility to antibiotics of staphylococci strains isolated from clinically ill or healthy dogs and cats, during the period August 2002-July 2003. A total of 136 staphylococci (87 coagulase-positive and 49 coagulase-negative) were investigated for antibiotic resistance, using disk diffusion and minimum inhibitory concentration (MIC) test. The mecA gene was detected using the polymerase chain reaction. The isolates belonged to the species S. aureus (53 isolates), S. intermedius (34 isolates), S. epidermidis (26 isolates) and other coagulase-negative staphylococci (CNS, 23 isolates). Of the 136 isolates, 43 (31.6%) were mecA-positive and the frequency of the ,presence of mecA gene varied among the different species. All S. aureus strains were mecA-negative and were found to be susceptible, with an oxacillin MIC $\leq$1 $\mu\textrm{g}$/ml. Five (13.6%) isolates of 36 that exhibited oxacillin resistance on the MIC testing were found to be mecA-negative, suggesting not all mecA-positive strains may be an oxacillin resistant. However, the mecA presence of the strains was correlated with high oxacillin resistance: 71.4% (10 isolates of 14; P < 0.001) for mecA-positive S. intermedius and 72.4% (21 isolates of 29; P < 0.001) for mecA-positive CNS isolates. About 69% (94 isolates of 136) showed resistance to at least one drug, and 22.8% (31 isolates) were resistant to four or more different drug classes. Resistance (36 isolates, 71.7%) to penicillin G was a common finidng. This study suggest that the mecA-positive staphylococci are prevalent in small animals, and selection of antibiotics to treat infections caused by mecA-positive staphylococci may be very limited because of multi-drug resistance.