• IMMUNE NETWORK
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• v.22 no.3
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• pp.28.1-28.11
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• 2022

The 26S proteasome irreversibly hydrolyzes polyubiquitylated substrates to maintain protein homeostasis; it also regulates immune responses by generating antigenic peptides. An alternative form of the 26S proteasome is the immunoproteasome, which contains substituted catalytic subunits (β1i/PSMB9, β2i/PSMB10, and β5i/PSMB8) instead of constitutively expressed counterparts (β1/PSMB6, β2/PSMB7, and β5/PSMB5). The immunoproteasome expands the peptide repertoire presented on MHC class I molecules. However, how its activity changes in this context is largely elusive, possibly due to the lack of a standardized methodology to evaluate its specific activity. Here, we describe an assay protocol that measures the immunoproteasome activity of whole-cell lysates using commercially available fluorogenic peptide substrates. Our results showed that the most accurate assessment of immunoproteasome activity could be achieved by combining β5i-targeting substrate Ac-ANW-AMC and immunoproteasome inhibitor ONX-0914. This simple and reliable protocol may contribute to future studies of immunoproteasomes and their pathophysiological roles during viral infection, inflammation, and tumorigenesis.

• Mycobiology
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• v.37 no.3
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• pp.183-188
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• 2009

The molecular phylogeny in nine different commercial cultivated strains of Pleurotus nebrodensis was studied based on their internal transcribed spacer (ITS) region and RAPD. In the sequence of ITS region of selected strains, it was revealed that the total length ranged from 592 to 614 bp. The size of ITS1 and ITS2 regions varied among the strains from 219 to 228 bp and 211 to 229 bp, respectively. The sequence of ITS2 was more variable than ITS1 and the region of 5.8S sequences were identical. Phylogenetic tree of the ITS region sequences indicated that selected strains were classified into five clusters. The reciprocal homologies of the ITS region sequences ranged from 99 to 100%. The strains were also analyzed by RAPD with 20 arbitrary primers. Twelve primers were efficient to applying amplification of the genomic DNA. The sizes of the polymorphic fragments obtained were in the range of 200 to 2000 bp. RAPD and ITS analysis techniques were able to detect genetic variation among the tested strains. Experimental results suggested that IUM-1381, IUM-3914, IUM-1495 and AY-581431 strains were genetically very similar. Therefore, all IUM and NCBI gene bank strains of P. nebrodensis were genetically same with some variations.

• Mycobiology
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• v.41 no.4
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• pp.252-255
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• 2013

Fungal pathogens have caused severe damage to the commercial production of Pleurotus eryngii, the king oyster mushroom, by reducing production yield, causing deterioration of commercial value, and shortening shelf-life. Four strains of pathogenic fungi, including Trichoderma koningiopsis DC3, Phomopsis sp. MP4, Mucor circinelloides MP5, and Cladosporium bruhnei MP6, were isolated from the bottle culture of diseased P. eryngii. A species-specific primer set was designed for each fungus from the ITS1-5.8S rDNA-ITS2 sequences. PCR using the ITS primer set yielded a unique DNA band for each fungus without any cross-reaction, proving the validity of our method in detection of mushroom fungal pathogens.

• The Korean Journal of Mycology
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• v.44 no.4
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• pp.346-349
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• 2016

During a survey of fungal diversity of the order Mortierellales, a zygomycete strain, EML-YS717-1, was isolated from a freshwater sample collected from the Yeongsan River in Gwangju, Korea. Based on its morphological characteristics and a phylogenetic analysis of the internal transcribed spacer (ITS1 and ITS2) and 5.8S rDNA sequences, the strain was identified as Mortierella minutissima. To the best of our knowledge, M. minutissima, has not previously been authentically reported in Korea.

• Journal of Periodontal and Implant Science
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• v.26 no.2
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• pp.365-375
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• 1996

5 serotypes(a, b, c, d, e) of Actinobacillus actinomycetemcomitans showed distinct hybridization patterns(DNA fingerprinting patterns) when the bacterial DNA were hybridized with randomly cloned 4.7-Kb sized DNA probe. The sizes of hybridized bands in each serotypes were different among serotypes and represented unique patterns of hybridization with the probe used. The serotype a showed two bands of fingerprinting patterns: 23.1 kb and 2.5 kb respectively. Serotype b and c showed single band: 6.6 kb and 9.5 kb, respectively. Serotype d and e showed two bands of hybridization: 23.1 kb and 2.8 kb, and 23.7 kb and 2.1 kb, respectively. The results indicate that this standard fingerpriting patterns of DNA hybridization with 4.7 kb probe can be further used for genotyping clinical isolates of Actinobacillus 8ctinomycetemcomitansand its relevance with periodontal disease activity.

• The Korean Journal of Food And Nutrition
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• v.14 no.6
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• pp.548-561
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• 2001

Listeria spp. from sea water, fishes and shellfishes have been troubled in many countries. So we exam ined its distribution rates, biochemical characteristics of a separated strain, growth curve of pH at set times to 4 species of standard strain, and yes or no of growth inhibition for precautionary measure of food poisoning by L. monocytogenes, garlic, mustard, wasabi, and green tea extracts including sensitivity of antibiotics 10 species. As its results, check numbers of its positivity to Listeria spp. were 32 species in total examination body 200 species, and its isolation rates were 16%, L. innocua was 14.0%, L. monocytogenes 1.0%, and L. seeligeri 1.0% by the strain species. All the standard strain of 4 species showed growth inhibition bellow pH 3.0, its pH conditions of the optimum growth at 7.0∼8.0, and its growth was more active in alkali co]tuition than in acid condition. Its growth inhibition examination by garlic extracts had an the worst effects with O.D values of 0.078∼0.210. But the case of mustard and wasabi had weakened effect, and the case of green tea had some effect as the time went by. The results of sensitivity examination of antibiotics 10 species were as fellows. L. innocua of the 16 cases showed sensitivity of 100% in all 5 species, Ampicillin, etc, and Ciprofloxacin showed sensitivity of 43.7% and gentamicin, 93.7%. But tetracycline showed tolerance of 31.3% , cefotaxine. 75%, nalidixic acid, 100%. L. monocytogenes of the 6 cases showed sensitivity of 100% in all 6 species, ciprofloxacin, etc.

• The Korean Journal of Mycology
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• v.38 no.2
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• pp.105-111
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• 2010

Lentinus lepideus, known as train wrecker fungus, has been used for nutritional and medicinal purposes. Recently, commercial cultivation technique and a new cultivar of the mushroom were developed. To investigate the genetic diversity and phylogenetic relationship for identifying the mushroom strains and cultivar, one commercial and 13 strains of Lentinus lepideus from different geographical regions of Korea were analyzed by ITS regions of rDNA and RAPD of genomic DNA. Three strains of Lentinus edodes were also used for the analysis. The size of the ITS1 and ITS2 regions of rDNA from the different strains varied from 173 to 179 bp and 203 to 205 bp, respectively. The sequence of ITS1 was more variable than that of ITS2, while the 5.8S sequences were identical with 156 base pairs. A phylogenetic tree based on the ITS region sequences indicated that selected strains could be classified into four clusters, while 3 strains of L. edodes was divided into a new cluster. Ten primers out of 20 arbitrary primers used in the RAPD-PCR efficiently amplified the genomic DNA. The numbers of amplified DNA bands varied with the primers and strains, with polymorphic DNA fragments in the range from 0.2 to 2.6 kb. The results showed that phylogenetic relationship among Korean strains of Lentnus lepideus is high, but genetic diversity is low.

• Journal of Plant Biology
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• v.8 no.1_2
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• pp.11-18
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• 1965

Since Taquet's first discovery of wild P. yedoensis at Mt. Halla, Korea, in 1908, its morphological chracteristics and question of origin of cultivated yedoensis have given controversies to the botanists. Takenaka, through his experiments on the hybridity of cultivated P. yedoensis, recently holds the opinion that P. yedoensis might have originated in Izu peninsula, Japan. The author presents the summarized report on the wild P. yedoensis and its putative parents based on his 2 years' investigated carried out at Mt. Halla during his breeding experiment of genus Prunus. The species of cherry tree used in the present investigation were identified by Prof. Mankyu Park and Mr. Jonghyu Pu, Korean taxonomists. 1) Wild cherry trees which grow wild in Mt. Halla and whose blooming season is April are mostly P. subhirtella var. pendula form. ascendens and P. donarium P. yedoensis is rare in number, around 10 individuals, having been found in a half century. 2) Individuals of wild yedoensis are variable in some of their morphological characteristics. This is, also, true in other species of Prunus. 3) Wild yedoensis whose vigorous growth, sterility, and rarity in number suggest hybrid origin, has intermediate characteristics between the P. subhirtella and P. donarium. 4) Due to the abnormal weather of the island and various environmental factors such as havbitats, some of the early-blooming subhirtella and late-blooming donarium would bloom at the same time, giving these two species the changes to cross. 5) Wild yedoensis is slightly different in some of its quantitative characters from cultivated species.

• Mycobiology
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• v.37 no.4
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• pp.258-266
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• 2009

Pleurotus eryngii, known as king oyster mushroom has been widely used for nutritional and medicinal purposes. This study was initiated to screen the suitable conditions for mycelial growth and to determine the phylogenetic relationship of the selected strains. Optimal mycelial growth was observed at $30{^{\circ}C}$ and minimum mycelial growth observed at $10{^{\circ}C}$. This mushroom tolerates a broad pH range for mycelial growth, with most favorable growth observed at pH 6. Results also indicated that glucose peptone, yeast malt extract and mushroom complete media were favorable growth media, while Hennerberg and Hoppkins media were unfavorable. Dextrin was the best and xylose the least effective carbon sources. Results revealed that inorganic nitrogen sources were less effective than organic sources for the mycelial growth of P. eryngii. Investigation of genetic diversity is necessary to identify the strains. The ITS region of rDNA were amplified using PCR. The size of the ITS1 and ITS2 regions of rDNA from the different strains varied from 214 to 222 bp and 145 to 236 bp, respectively. The sequence of ITS2 was more variable than that of ITS1, and the 5.8S sequences were identical. A phylogenetic tree based on the ITS region sequences indicated that selected strains could be classified into six clusters. Fourteen IUM and ATCC- 90212 strains were also analyzed by RAPD with 20 arbitrary primers. Fourteen of these primers were efficiently amplified the genomic DNA. The number of amplified bands varied with the primers and strains, with polymorphic fragments in the range from 0.2 to 2.3 kb.

• Korean Journal of Microbiology
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• v.55 no.3
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• pp.234-241
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• 2019

An intensive interaction between yeasts and insects has highlighted their relevance for attraction to food and for the insect's development and behavior. Yeast associated in the gut of insects secretes cellulase which aided in the food digestion (cellulose degradation). Three strains of cellulose-degrading yeast were isolated from the gut of adult grasshoppers collected in Gyeonggi Province, South Korea. The strains $ON22^T$, $G10^T$, and $G15^T$, showed positive cellulolytic activity in the carboxymethyl cellulose (CMC)-plate assay. The phylogenetic tree based on sequence analysis of D1/D2 domains of the large subunit rRNA gene and the internal transcribed spacer (ITS) regions revealed that the strains $ON22^T$ (100 and 98.4% sequence similarities in D1/D2 domains and ITS) and $G10^T$ (99.8 and 99.5% in D1/D2 domain and ITS region) were most closely related to the species Moesziomyces aphidis JCM $10318^T$; $G15^T$ (100% in D1/D2 domains and ITS) belongs to the species Moesziomyces antarcticus JCM $10317^T$, respectively. Morphology and biochemical test results are provided in the species description. Cellulase with its massive applicability has been used in various industrial processes such as biofuels like bioethanol productions. Therefore, this is the first report of the cellulolytic yeast strains $ON22^T$, $G10^T$, and $G15^T$ related to the genus Moesziomyces in the family Ustilaginaceae (Ustilaginales), in Korea.