• Journal of Mushroom
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• v.10 no.1
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• pp.37-43
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• 2012

This study was carried to identify a correct species and asses genetic diversity within the same species of Polyporus spp. preserved in Division of applied Microbiology. Contaminated isolates showed different growth rates, morphology and color of hyphae. We have reconstructed the phylogenetic tree of a select group of Polyporus spp. using nucleotide sequences of the internal transcribed spacer region(ITS) region. The phylogenetic tree was constructed by using the neighbor-joining method. PELF primers of 20-mer were used to assess genetic diversity of preserved isolates. Sequence analysis showed that three strains were different species and four strains were identified completely different nomenclature. According to the analysis of ITS sequences, the genus Polyporus clustered into five distinct group, most of which correlated with species-groups identified by RAPD method. Four isolates included strain PM02 showed high similarity with P. arcularius, four isolates included strain PM03 high similarity with P. alveolaris, three isolates included strain PM01 high similarity with P. tuberaster, and PM 06 and PM04 high similarity with P. brumalis and P. squamossus. Isolates were collected in the United States(PM10, PM11) was identified as P. alveolarius and P. arcularius. RAPD analysis of genetic polymorphisms of genus Polyporus showed a very different band patterns. As the result of RAPD and ITS region sequences analysis for preserved isolates, it seems likely that 6 isolates of Polyporus spp. may be need to reclassify or eliminate from preserved catalogue.

• Parasites, Hosts and Diseases
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• v.47 no.3
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• pp.259-264
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• 2009

Genetic polymorphisms of encoding antigen B2 gene (AgB2) in Echinococcus granulosus were studied using PCR-RFLP and DNA sequencing among 20 Egyptian isolates. Five isolates from different host origins (humans, camels, pigs, and sheep) were collected and used. All examined isolates of each host group gave very similar patterns of PCR-RFLP after restriction enzyme digestion with Alul, with the gene size of approximately 140 bp and 240 bp for sheep and human isolates, and approximately 150 bp and 250 bp for pig and camel isolates. No digestion pattern was obtained after incubation of all studied isolates with EcoRI. These results reveal high intra-group homogeneity. DNA sequence analysis highlighted that human infecting strain showed 100% identity with respect to sheep infecting isolate, 96% and 99% with pig and camel infecting isolates, respectively.

• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.199-206
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• 2008

Four hundred and thirteen oxytetracycline-resistant bacteria were recovered from six freshwater giant prawn farms with a history of oxytetracycline use. Most oxytetracycline-resistant isolates were Gram-negative bacteria. Six groups of oxytetracycline-resistant bacteria were classified using cluster analysis based on a comparison of levels of oxytetracycline resistance. Complex fingerprint patterns were obtained for 71 isolates studied. In general, the band patterns of isolates from different ponds were very similar, and the data indicated that the isolates were closely related. The exploration for cross-resistance found that most of the 71 oxytetracycline-resistant isolates were also resistant to tetracycline and chlortetracycline, but had a relatively low resistance to doxycycline. Many isolates showed higher chlortetracycline resistance than oxytetracycline resistance. Additionally, the oxytetracycline-resistant isolates were examined for the presence of tetracycline resistance (tet) genes. Fifty percent of the isolates carried one of the 14 known tet genes examined. The most common determinants were TetA and TetD. However, TetB, TetC, TetE, TetK, TetL, and TetM were also found with various frequencies.

• Mycobiology
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• v.35 no.2
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• pp.100-102
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• 2007

Pet dogs have been considered to be involved in the contamination of indoor air by serving as a source of providing molds at houses. Currently, information on the molds originated from pet dogs is rarely available in Korea. The present study was carried out to obtain basic information on the fungi present on pet dogs. For this, fungal isolation was performed to the skin and hairs of 70 pet dogs at different houses and veterinary hospitals. A total of 44 fungal isolates were obtained from skin (27 isolates) and hairs (17 isolates) of the dogs investigated. Based on the observation of microstructures and colony morphology, and the ITS rDNA sequence analysis, the fungal isolates were identified at the level of genus. The identified isolates belong to the genera of Alternaria, Aspergillus, Beauveria, Chrysosporium, Cladosporium, Penicillium, Scopulariopsis, and Trichoderma. Among these genera, Aspergillus (25%), Cladosporium (23%) and Penicillium (20.5%) were 3 major genera. 63% of the 44 isolates showed color changes on dermatophyte test medium (DTM). When we tested the growth ability of 44 isolates at $37^{\circ}C$, 45% of the isolates were able to grow. These results show that pet dogs could carry fungi having a potentiality of affecting on human health.

• The Plant Pathology Journal
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• v.34 no.3
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• pp.182-190
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• 2018

Powdery mildew caused by the obligate biotrophic fungus Podosphaera xanthii poses a serious threat to melon (Cucumis melo L.) production worldwide. Frequent occurrences of the disease in different regions of South Korea hints at the potential existence of several races which need to be identified. The races of five isolates collected from different powdery mildew affected regions were identified based on the pathogenicity tests of these isolates on eight known differential melon cultigens namely, SCNU1154, PMR 45, WMR 29, PMR 5, MR-1, PI124112, Edisto 47 and PI414723. None of the isolates have shown same disease responses to those of the known races tested in this study and in previous reports on these identical differential melon cultigens. This indicates that the tested uncharacterized isolates are new races. Among the isolates, the isolates from Hadong, Buyeo, Yeongam and Gokseong have shown same pathogenicity indicating the possibility of these isolates being one new race, for which we propose the name 'race KN1'. The isolate of Janghueng have also shown unique disease response in the tested differential melon cultigens and hence, we identified it as another new race with a proposed name 'race KN2'. Report of these new races will be helpful in taking effective control measures in prevalent regions and for future breeding programs aimed at developing varieties that are resistant to these race(s).

• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.778-783
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• 1999

Campylobacter is a pathogen for both humans and animals that can be transferred from animals to humans. Four isolates, which grew under 5-10% $CO_2$ and had small and translucent colonies, were obtained from swine gastric mucosa and characterized using various methods. These bacteria were gram negative, spirally shaped with round ends. One or two non-sheathed polar flagella were observed under electron microscopy. A PCR with species-specific protein (SSP) primers for 16S rRNA gene in Campylobacter produced a typical 462 bp fragment. The isolates had various biochemical and molecular characteristics which differentiated them from other Campylobacters. The isolates were catalase and oxidase positive, urease (rapid) negative, nitrate reduction positive, indoxyl acetate hydrolysis positive, y-glutamyl transpeptidase negative, and alkaline phosphatase negative. All four isolates showed growth at $37^{\circ}C{\;}and{\;}42^{\circ}C{\;}but{\;}not{\;}at{\;}25^{\circ}C$, were resistant to cephalotin and cefoperazone, and susceptible to carbenicillin. The isolates showed various results in the reduction of chloride to triphenyl tetrazolium (TTC) and a susceptibility to nalidixic acid. Western blot analysis of these isolates with antiserum raised against one isolate showed different patterns from those of reference strains. A dendrogram drawn with the RAPD results showed that these isolates belonged to a new Campylobacter spp. group different from those of C. jejuni, C. doylei, C. lari, and C. coli.

• Journal of Microbiology and Biotechnology
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• v.24 no.3
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• pp.386-393
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• 2014

Possible cross-transmission of hospital-associated enterococci between human patients, medical staff, and hospital environments has been extensively studied. However, limited information is available for veterinary hospital-associated Enterococcus isolates. This study investigated the possibility of cross-transmission of antibiotic-resistant enterococci between dog patients, their owners, veterinary staff, and hospital environments. Swab samples (n=465) were obtained from five veterinary hospitals in Seoul, Korea, during 2011. Forty-three Enterococcus strains were isolated, representing seven enterococcal species. E. faecalis and E. faecium were the most dominant species (16 isolates each, 37.2%). Although slight differences in the antibiotic resistance profiles were observed between the phenotypic and the genotypic data, our antibiogram analysis demonstrated high prevalence of the multiple drug-resistant (MDR) isolates of E. faecalis (10/16 isolates, 62.5%) and E. faecium (12/16 isolates, 75.0%). Pulsed-field gel electrophoretic comparison of the MDR isolates revealed three different clonal sets of E. faecalis and a single set of E. faecium, which were isolated from different sample groups or dog patients at the same or two separate veterinary hospitals. These results imply a strong possibility of cross-transmission of the antibiotic-resistant enterococcal species between animal patients, owners, veterinary staff, and hospital environments.

• The Journal of Korean Society of Virology
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• v.30 no.3
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• pp.203-210
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• 2000

Hantaviruses are etiologic agents of hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS) in the world. Various hantaviruses were isolated from HFRS patients and several different rodent species in the world. Four hantavirus isolates from Indonesia and three isolates from Thailand among 89 Bandicotas captured in Yogyakarta, east region of Sumatra island, Indonesia and at Chiang Mai in Thailand during 1996 were made through several passages in Vero E6 cells. Viral genome M segment from two Indonesian isolates and three Thailand isolates were amplified using hantavirus generic primers of the M segment and cloned into pCRII vector. The genetic differences were analyzed by comparison of partial sequence of the M segment and antigenic differences were made by IFA. Nucleotide sequence homology of two isolates BC 8, BC 34 from Indonesia and two isolates thai 1322, thai 1330 to Seoul virus was 99% and 96%, respectively, but Thai 1164 was 80%Thai 1164 strain has shown 95% homology to Thai 749 virus. In conclusion it is indicated that two different serotype hantaviruses, Seoul and Thailand, are cocirculating among Bandicota in Thailand, in contrast Seoul serotype virus is circulating in Indonesia.

• The Journal of the Korean Society for Microbiology
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• v.20 no.1
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• pp.1-11
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• 1985

A total of 211 strains of Staphylococcus aureus which included 118 strains isolated from various clinical specimens of admitted patients of University Hospital with systemic or severe cases of infection and 93 strains from infected skin diseases of out-patients of dermatology clinic located in rural area, were tested for the antimicrobial susceptibility to the 12 drugs of common use and the phage typing. An these were subjected to the study of plasmid profile analysis for the molecular epidemiology of nosocomial infections. University Hospital(UH) isolates showed higher frequency of resistance than local clinic(LC) isolates against 10 drugs excluding tetracycline(Tc), and trimethoprim(Tp). The MIC of UH isolates were above than $128{\mu}g/ml$ against 9 drugs except Tc, gentamicin(Gm), and Tp, but LC isolates did not show such a high level of MIC. There was difference of MIC needed to inhibit 90% of strains(MIC90) against each drugs tested between two groups of UH and LC isolates. UH isolates showed 2 to 4 times higher value of MIC90 by two-fold serial dilution of drug concentration than LC isolates. Tp was considered as an effective drug in treatment of staphylococcal infections whereas ampicillin and Gm were appeared to be ineffective. Seventy-three strains(61.9%) of UH isolates and 70(69.9%) of LC were typable with phages from Colindale Reference Laboratory. The prevailing phage type of UH isolates belonged to lytic group II were 27 strains(22.9%) and those of LC isolates belonged to lytic group II were 23 strains(24.7%). Thirteen strains(11.0%) of UH isolates were multiply resistant to more than 5 drugs to 10 drugs but none of LC isolates. Through the lysis method of Kado and Liu followed by agarose gel electrophoresis, none of 211 strains showed plasmid profile. These results were confirmed by re-examination through the method of Birnboim and Doly.

• The Plant Pathology Journal
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• v.17 no.5
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• pp.276-280
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• 2001

Fusarium isolates of Gibberella fujikuroi species complex were obtained from sorghum grown in five provinces of Korea in 1996 and 1997. These isolates were characterized based on their mating behavior, mycotoxin production, and vegetative compatibility. Only three mating populations (A, D, and F) were recovered from a total of 155 isolates examined. The relative frequency of the mating populations was significantly different: F was predominant (80%), while D and A were observed at low frequencies of 9% and 3%, respectively. Female fertile isolates were more common within F (44 our of 124) than D (2 out of 14), while none of the five A isolates were female fertile. The inbreeding effective population sizes ($\textrm{N}_e$)for mating type and male/hermaphrodite ratios in mating populations A and D produced significant amounts of fumonisins, while F isolates produced none or only traces of fumonisin B$_1$. In contrast. F isolates produced higher amounts of moniliformin (average of 3,820 ppm) than A and D isolates (averages of 77 and 1,819 ppm, respectively). Fifty-one isolates were tested for vegetative compatibility using nitrogen non-utilization mutants of each isolate, and 44 vegetative compatibility groups (VCGs) were identified. A single VC type (VC1) was found in all of the five A isolates examined. Six of the D isolates examined consisted of three VC types: two for VC2, two for VC3, and the rest for VC4. All of the F isolates tested were incompatible in every combination and , thus, each constituted a unique VCG.