• Mycobiology
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• v.41 no.4
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• pp.245-247
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• 2013

The ambrosia beetle, Platypus koryoensis, is an economically important pest affecting oak trees in Korea. Candida kashinagacola was isolated from galleries of the beetle in oak wood and identified by analyses of morphology, physiological properties, and nucleotide sequence of the large subunit ribosomal DNA. This is the first report on Candida species associated with oak wilt disease vectored by the ambrosia beetle, Platypus koryoensis, in Korea.

• Proceedings of the Korean Biophysical Society Conference
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• 2001.06a
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• pp.38-38
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• 2001

We cloned the cDNA encoding the neuron-specific $\beta$-subunit ($\beta$4) of large-conductance calcium-activated potassium channels from rat brain and determined the DNA sequences of the entire coding region (GenBank accession; AY028605). The deduced amino acid sequences of r$\beta$4, 210 amino acids in length, are closely related to the $BK_{Ca}$ $\beta$4 subunits of other species but show only limited sequence homology to other $\beta$-subunits, $\beta$1-$\beta$3.(omitted)d)

• The Korean Journal of Mycology
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• v.47 no.1
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• pp.35-42
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• 2019

We isolated endophytic fungi from the conifer leaves of Pinus densiflora inhabiting Buan-gun, Jeollabuk-do, Korea. We identified the isolated fungal strains based on phylogenetic analysis performed using the nucleotide sequences of the internal transcribed spacer, large subunit, and beta-tubulin. We confirmed the presence of three novel endophytic fungi in Korea, namely Paracamarosporium hawaiiense, Tubakia dryina, and Zasmidium fructigenum. In this report, we described the morphological characteristics of these fungal strains and the results of their phylogenetic analysis.

• The Korean Journal of Mycology
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• v.51 no.1
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• pp.57-62
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• 2023

In Korea, Cornus controversa and C. florida are known as hosts of Erysiphe pulchra from section Microspharea of the genus Erysiphe. However, recent molecular-phylogenetic analyses on the internal transcribed spacer regions and large subunit gene of the rDNA revealed that the Erysiphe powdery mildew on C. controversa in Japan is in fact E. cornicola. To assess the taxonomic status of Erysiphe-C. controversa association in Korea, isolates collected since 1987 were investigated and consequently identified as E. cornicola based on molecular-phylogenetic analyses and new morphological traits. To our knowledge, this is the first study to confirm the presence of this powdery mildew in Korea.

• The Korean Journal of Mycology
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• v.51 no.4
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• pp.411-417
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• 2023

In July 2023, previously unrecorded fungi belonging to the genus Helvella were collected from the city of Taebaek, South Korea. These fungi are morphologically similar to Helvella crispa, but their differences include a wide, saddle-shaped apothecium and white hair on the receptacle surface. By analyzing DNA sequences combining the internal transcribed spacer (ITS) and nuclear ribosomal large subunit (nrLSU) regions and comparing them with various related species of Helvella, the collected fungi were identified as H. orienticrispa.

• The Korean Journal of Mycology
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• v.51 no.3
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• pp.239-243
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• 2023

The Golovinomyces biocellatus complex is known to consist of powdery mildew from the Golovinomyces genus, associated with host plants from the Lamiaceae family. Recent molecular phylogenetic analyses have resolved the taxonomic composition of this complex, and Golovinomyces biocellatus sensu stricto is considered to be a pathogen of Glechoma species, globally. However, this paper presents a new finding of Golovinomyces salviae on Glechoma longituba, besides its original host species of Salvia. This information was inferred by molecular phylogenetic analyses from the multi-locus nucleotide sequence dataset of intergeneric spacer (IGS), internal transcribed spacer (ITS), large subunit (LSU) of rDNA, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene. Further, the asexual morphology of this fungus is described and illustrated.

• Proceedings of the Korean Society of Food Hygiene and Safety Conference
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• 2002.05a
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• pp.215-215
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• 2002

Catalytic subunit of pyruvate dehydrogenase phosphatase (PDPc) has been suggested to have three major funational domains such as dihydrplipoamide adetyltransferase(E2)-binding domain, regulatory subunit of PDP(PDP)r-binding domain, and calcium-binding domain. In order to identify functional domains, recombinant catalytic subunit of pyruvate dehydrogenase phosphatase(rPDPc) was expressed in E. coli JM101 and purified to near homogeneity using the unique property of PDPc: PDPc binds to the inner lipoyl domain (L2) of E2 of ppyruvate dehydrogenase complex (PDC) in the presence of Ca+2, not under EGTA. PDPc was limited-proteolysed by typsin, chymotypsin, Arg-C, and elastase at pH 7.0 and 30C and N-terminal analysis of the fragments was done. Chymotrypsin, trypsin, and elastase made two major fragments: N-terminal large fragment, approx. 50kD and C-terminal small fragment, approx.10 kDa. Arg-C made three major fragments: N-terminal fragment, approx. 35kD, and central fragment, approx. 15 kD, and C-terminal fragment, approx. 10 kD. This study strongly suggest that PDPc consists of three major functional domains. However, further study should be necessary to identify the functional role.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.4
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• pp.680-683
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• 2002

Bovine aortic endothelial cells(BAEC) produce two variant forms of laminin with a subunit composition of AB1B2 and A'B1B2. Analyses of the intracellular assembly of these subunits revealed that the B1B2 dimer formed first, and that A or A' joined to form the AB1B2 or A'B1B2 trimer. Angiostatic steroids shifted the relative size of the A and A' monomer pool in BAEC, and competition between the A and A' subunits in joining the B1B2 dimer produced AB1B2 and A'B1B2 in different ratios. This result suggests that subunit replacement is the general mechanism for producing laminin variants by various cells for tissue morphogenesis. When laminin subunits in BAEC were cross-linked with dithio-bis-succinimidylpropionate(DSP) and immunoprecipitated with anti-Iaminin antiserum, monomeric A,A',B1 and B2 monomers and the B1B2 dimer migrated as extremely large molecules in sodium dodecyl sulfate gel electrophoresis under nonreducing conditions. When the crosslinking disulfide bonds were cleaved under reducing conditions, they migrated as the usual subunits. This result suggests that molecular chaperones were involved in the process of the assembly and replacement of laminin subunits.

• Journal of Power Electronics
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• v.13 no.5
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• pp.746-756
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• 2013

The modularized subunit of an electronic power transformer (EPT) is a series connection of two H-bridge voltage-source converters and a DC-DC converter with a high-frequency isolation transformer (HFIT). On the basis of cascading and paralleling the modularized subunits, EPT can be used in high-voltage and large-current applications in the power system. This paper discusses the steady state analysis of the modularized subunit of EPT. Theoretical analysis considers the influences of the two H-bridge voltage-source converters on the two sides of the DC-DC converter. We deduce the formulas of the theoretical calculation on the internal electrical characteristics of EPT (e.g., the voltages of the DC-bus capacitor and the primary side peak current of the HFIT). This paper provides guidance on the design and selection of EPT key elements (e.g., the DC-bus capacitors and HFIT). Experimental results are obtained from a single subunit of a laboratory model rated at 962 V, 15 kVA. All calculations, simulations, and experiments confirm the theoretical analysis of the subunit of EPT.

• Mycobiology
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• v.48 no.6
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• pp.464-475
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• 2020

Acervus (Pyronemataceae, Pezizales) is a saprobic genus in Pezizomycetes, characterized by colored apothecia, subcylindrical to cylindrical asci and guttulate ascospores. We collected four Acervus samples from China and Thailand. Descriptions and illustrations are introduced for all fresh samples. One new record of A. globulosus from Thailand, one new species, A. rufus, two known species, A. epispartius and A. stipitatus from China are reported. Phylogenetic analysis based on five genes, the large subunit rRNA (LSU), the translation elongation factor-1 alpha (tef1-α), the second largest subunit of RNA polymerase II (rpb2), the largest subunit of RNA polymerase II (rpb1), and the small subunit rRNA (SSU), revealed the distinct position of the new species. The new species is set apart by its red apothecia. A key to Acervus species is also given.