• Journal of Microbiology and Biotechnology
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• v.25 no.10
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• pp.1648-1652
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• 2015

Azaphilone polyketides are synthesized by iterative non-reducing fungal polyketide synthases (NR-fPKSs) with a C-terminus reductive domain (-R). Several azaphilone biosynthetic gene clusters contain a putative serine hydrolase gene; the Monascus azaphilone pigment (MAzP) gene cluster harbors mppD. The MAzP productivity was significantly reduced by a knockout of mppD, and the MAzP NR-fPKS-R gene (MpPKS5) generated its product in yeast only when co-expressed with mppD. Site-directed mutations of mppD for conserved Ser/Asp/His residues abolished the product formation from the MpPKS5/mppD co-expression. MppD and its homologs are thus proposed as a new protein factor involved in the product formation of NR-fPKS-R.

• Elastomers and Composites
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• v.24 no.1
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• pp.19-25
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• 1989

• Journal of agriculture & life science
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• v.45 no.6
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• pp.1-7
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• 2011

This work was performed to confirm the molecular discrimination through the nrITS1 sequences among 3 taxa of Scirpus L. sensu lato (s.l.) species. S. planiculmis represented only 2 base sequence variations with S. maritimus in spite that they showed different morphological features. The nucleotide sequences of the ITS1 region from S. planiculmis were shown to have 99.1% homology with S. maritimus and 60.4% homology with S. triqueter. Although the morphology of S. planiculmis is similar with S. triqueter, molecular basis of the size and sequences on ITS1 region were shown to have distinctive differences. For divergency investigation on same sites and metapopulation, sequencing was conducted on ITS1 region with partial 5.8S and 18S regions. All plants of each species collected at the same site had identical band size pattern and sequences. Intraspecific molecular divergency was not identified in spite that these species live in different wetland sites. The ITS1 sequences described here provided a powerful genetic tool for phylogenetic studies which was difficult by morphological identification as high rate of morphological plasticity.

• Elastomers and Composites
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• v.56 no.4
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• pp.243-249
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• 2021

The demand for truck bus radial (TBR) tires with enhanced fuel efficiency and wear resistance have grown in recent years. In addition, as the issue of particulate matter and air pollution increases, efforts are being made to reduce the generation of particulate matter. In this study, we investigated the effect of varying the content of butadiene rubber (BR) on the properties of the rubber compounds and the amount of particulate matter in the TBR tire tread compound. Furthermore, we utilized carbon black in the NR/BR blend compounds owing to its excellent compatibility, and we used silica in the ENR-25/BR blend compounds because it can interact chemically with epoxide groups. The NR/BR blend compounds and the ENR-25/BR blend compounds were evaluated by varying their BR content between 20 phr and 30 phr. The results showed that the ENR-25/BR blend compounds had superior wear resistance than the NR/BR blend compounds. This was caused by the interaction between silica and ENR. In addition, it was confirmed that the increased wear resistance as the BR content increased. Furthermore, compared to the NR/BR blend compounds, ENR-25/BR blend compounds exhibited a lower tan 𝛿 value at 60℃ because silica was used as filler. This indicates a higher fuel efficiency. The measurement results for wear particulate matter showed that as increasing the BR content resulted in generation of less wear particulate matter. This was caused by the increased wear resistance. Moreover, the ENR-25/BR blend compounds with excellent filler-rubber interaction exhibited lower quantities of generated wear particulate matters as compared to the NR/BR blend compounds.

• BMB Reports
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• v.56 no.5
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• pp.314-319
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• 2023

Sepsis is a life-threatening multi-organ dysfunction with high mortality caused by the body's improper response to microbial infection. No new effective therapy has emerged that can adequately treat patients with sepsis. We previously demonstrated that interferon-β (IFN-β) protects against sepsis via sirtuin 1-(SIRT1)-mediated immunosuppression. Another study also reported its significant protective effect against acute respiratory distress syndrome, a complication of severe sepsis, in human patients. However, the IFN-β effect cannot solely be explained by SIRT1-mediated immunosuppression, since sepsis induces immunosuppression in patients. Here, we show that IFN-β, in combination with nicotinamide riboside (NR), alleviates sepsis by blocking endothelial damage via SIRT1 activation. IFN-β plus NR protected against cecal ligation puncture-(CLP)-induced sepsis in wild-type mice, but not in endothelial cell-specific Sirt1 knockout (EC-Sirt1 KO) mice. IFN-β upregulated SIRT1 protein expression in endothelial cells in a protein synthesis-independent manner. IFN-β plus NR reduced the CLP-induced increase in in vivo endothelial permeability in wild-type, but not EC-Sirt1 KO mice. IFN-β plus NR suppressed lipopolysaccharide-induced up-regulation of heparinase 1, but the effect was abolished by Sirt1 knockdown in endothelial cells. Our results suggest that IFN-β plus NR protects against endothelial damage during sepsis via activation of the SIRT1/heparinase 1 pathway.

• Journal of Species Research
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• v.9 no.4
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• pp.413-426
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• 2020

The Euphorbiaceae family features some of the most economically important plants that are sources of foods, oils, waxes, and medicines. The accurate identification of Euphorbiaceae species is critical in sustainable utilization of plant resources. We examined 234 sequences of nrDNA ITS, cpDNA rbcL and matK loci from 20 species in Euphorbiaceae in Korea and three outgroup taxa to develop efficient DNA barcodes. The three barcode loci were successfully amplified and sequenced for all Euphorbiaceae species. nrDNA ITS locus showed the highest mean interspecific K2P distance (0.3034), followed by cpDNA matK (0.0830), and rbcL (0.0352) locus. The degree of species resolution for individual barcode loci ranged from 75% (rbcL and matK) to 80% (ITS). The degree of species resolution was not enhanced with the different combinations of three barcode loci. The combined data set of the three loci(ITS+rbcL+matK) provided 80% of species resolution. These results confirm that ITS locus, as a single barcode, is the best option for barcoding of the Euphorbiaceae 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.

• Korean Journal of Plant Resources
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• v.27 no.3
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• pp.249-255
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• 2014

The rice belonging to Oryza sativa is not only has significant economic importance, for it is the major source of nutrition for about 3 billion all around the world. But also plays a vital role as a model organism, because it has a number of advantages to be a model plant, such as efficient transformation system and small genome size. Many methods and techniques have been conducted to attempt to distinguish different Oryza sativa species, such as amplified fragment length polymorphism (AFLP), random amplified polymorphic DNA (RAPD), simple sequence repeat (SSR) and so on. However, studies using sequence analysis of internal transcribed spacer (ITS), a region of ribosomal RNA has not been reported until now. This study was undertaken with an aim to understand the phylogenetic relationships among sixteen isolates of Oryza sativa collected from abroad and fifteen isolates collected from Korea, using ribosomal RNA (rRNA) internal transcribed spacer (ITS) sequences to compare the phylogeny relationships among different Oryza sativa species. The size variation obtained among sequenced nuclear ribosomal DNA (nrDNA) ITS region ranged from 515bp to 1000bp. The highest interspecific genetic distance (GD) was found between Sfejare 45 (FR12) and Anapuruna (FR15). Taebong isolate showed the least dissimilarity of the ITS region sequence with other thirty isolates. This consequence will help us further understanding molecular diversification in intra-species population and their phylogenetic analysis.

• Proceedings of the Zoological Society Korea Conference
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• 1998.10b
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• pp.129.1-129
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• 1998

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
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• 2003.08a
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• pp.117.3-117
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• 2003

No Abstract, See Full Text