• Korean Journal of Veterinary Research
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• v.58 no.2
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• pp.65-72
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• 2018

The present study observed the effects of a green tea (Camellia sinensis) flower extract (GTFE) on melanin synthesis in B16-F10 melanoma cells. GTFE exhibited antioxidant activity on 2,2-diphenyl-1-picrylhydrazyl and inhibited mushroom tyrosinase activity in a dose-dependent manner. Furthermore, GTFE significantly diminished ${\alpha}-melanocyte$ stimulating hormone (${\alpha}-MSH$) stimulated cellular melanin content and tyrosinase activity throughout the concentration range evaluated. Based on RNA sequencing analysis, differential gene expression patterns observed in ${\alpha}-MSH$ stimulated B16-F10 melanoma cells were normalized by the addition of GTFE. In particular, the expression levels of melanoregulin and tyrosinase genes which are key regulating genes in melanin synthesis were up-regulated by 3.5 and 3 fold respectively by ${\alpha}-MSH$, and were normalized to control levels by the addition of GTFE. The results suggest that GTFE inhibits melanin synthesis in ${\alpha}-MSH$ stimulated B16-F10 melanoma cells by normalizing expression of genes that are essential for melanin synthesis. Overall, the results suggest that GTFE could be applied in the development of a whitening agent for the treatment of dermal hyperpigmentation.

• Korean Journal of Exercise Nutrition
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• v.25 no.4
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• pp.24-37
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• 2021

[Purpose] To determine whether physical activity (PA), primarily the recommended 60 minutes of moderate-to-vigorous PA, is associated with gut bacterial microbiota in 10-year-old children. [Methods] The Block Physical Activity Screener, which provides minutes/day PA variables, was used to determine whether the child met the PA recommendations. 16S rRNA sequencing was performed on stool samples from the children to profile the composition of their gut bacterial microbiota. Differences in alpha diversity metrics (richness, Pielou's evenness, and Faith's phylogenetic diversity) by PA were determined using linear regression, whereas beta diversity (unweighted and weighted UniFrac) relationships were assessed using PERMANOVA. Taxon relative abundance differentials were determined using DESeq2. [Results] The analytic sample included 321 children with both PA and 16S rRNA sequencing data (mean age [SD] =10.2 [0.8] years; 54.2% male; 62.9% African American), where 189 (58.9%) met the PA recommendations. After adjusting for covariates, meeting the PA recommendations as well as minutes/day PA variables were not significantly associated with gut richness, evenness, or diversity (p ≥ 0.19). However, meeting the PA recommendations (weighted UniFrac R² = 0.014, p = 0.001) was significantly associated with distinct gut bacterial composition. These compositional differences were partly characterized by increased abundance of Megamonas and Anaerovorax as well as specific Christensenellaceae_R-7_group taxa in children with higher PA. [Conclusion] Children who met the recommendations of PA had altered gut microbiota compositions. Whether this translates to a reduced risk of obesity or associated metabolic diseases is still unclear.

• Journal of Microbiology and Biotechnology
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• v.5 no.5
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• pp.250-256
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• 1995

The ddh gene encoding meso-diaminopimelate (meso-DAP)-dehydrogenase (DDH) in Brevibacterium lactofermentum was isolated by complementation of the Escherichia coli dapD mutation. It was supposed from subcloning experiments and complementation tests that the evidence for DDH activity appeared in about 2.5 kb Xhol fragmented genome. The 2.5 kb Xhol fragment containing the ddh gene was sequenced, and an open reading frame of 960 bp encoding a polypeptide comprising 320 amino acids was found. Computer analysis indicated that the deduced amino acid of the B. lactofermentum ddh gene showed a high homology with that of the Corynebacterium glutamicum ddh gene.

• Journal of Life Science
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• v.30 no.1
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• pp.64-69
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• 2020

The European honeybee (Apis mellifera L.) has multiple anti-microbial peptides, but many were unknown and demands for their characterization have increased. This study therefore focused on identifying novel anti-microbial peptides (AMPs) from A. mellifera L. To obtain high-throughput transcriptome data of the honeybee, we implemented next-generation sequencing (NGS), isolating novel AMPs from total RNA, and generated 15,314 peptide sequences, including 44 known, using Illumina HiSeq 2500 technology. The uncharacterized peptides were identified based on specific features of possible AMPs predicted in the sequencing analysis. AMP5, one such uncharacterized peptide, was expressed in the epidermis, body fat, and venom gland of the honeybee. We chemically synthesized this peptide and tested its anti-bacterial activity against Gram-negative Escherichia coli (KACC 10005) and Gram-positive Bacillus thuringiensis (KACC 10168) by anti-microbial assay. AMP5 exhibited anti-bacterial activity against E. coli (MIC50=22.04±0.66 μM) but not against B. thuringiensis. When worker bees were injected with E. coli, AMP5 was up-regulated in the body fat. This study therefore identified AMP5 in adult European honeybees and confirmed its anti-bacterial activity against Gram-negative E. coli.

• Journal of Microbiology and Biotechnology
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• v.22 no.2
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• pp.215-219
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• 2012

The strain KCTC 11629BP, isolated from spontaneously fermented pine needle extract (FPE), showed fibrinolysis activity. The isolated strain was analyzed in physiological and biochemical experiments. Based on 16S rDNA sequencing and phylogenic tree analysis, the strain was identified to be a part of the genus Acetobacter, with Acetobacter senegalensis and Acetobacter tropicalis as the closest phylogenetic neighbors. Based on genotypic and phenotypic results, it was proposed that bacterial strain KCTC 11629BP represents a species of the genus Acetobacter. The strain was thusly named Acetobacter sp. FP1. In conclusion, Acetobacter sp. FP1 isolated from FPE possesses fibrinolytic activity.

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.307-311
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• 2005

Marine microorganisms to produce functional biopolymers were isolated from the seashore of the Kyungsang province. Microorganisms to hydrolyze carboxy-methyl cellulose(CMC) were cultured in marin broth and the other liquid medium that contained 2.0% (w/v) glucose, 0.25% yeast extract, 0.5% $K_2HPO_4$, 1% NaCl, 0.02% $MgSO_4{\cdot}7H_2O$ and 0.06% $(NH_4)_2SO_4$ to investigate the ability to produce carboxymethyl cellululase (CMCase) under aerobic conditions. Twelve microorganisms among them showed higher activities of CMCase than B. amyloliquefaciens DL-3, which was known as a cellulase-producing strain. The microorganism showing highest activity of CMCase in this study was identified as Bacillus subtilis subsp. subtilis with 16S rDNA partial sequencing and gyrase A partial sequencing and named as B. subtilis subsp. subtilis A-53.

• Journal of Microbiology and Biotechnology
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• v.23 no.10
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• pp.1381-1385
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• 2013

The centipede Scolopendra subpinipes mutilans is a medicinally important arthropod species. However, its transcriptome is not currently available and transcriptome analysis would be useful in providing insight into a molecular level approach. Hence, we performed de novo RNA sequencing of S. subpinipes mutilans using next-generation sequencing. We generated a novel peptide (scolopendrasin II) based on a SVM algorithm, and biochemically evaluated the in vitro antimicrobial activity of scolopendrasin II against various microbes. Scolopendrasin II showed antibacterial activities against gram-positive and -negative bacterial strains, including the yeast Candida albicans and antibiotic-resistant gram-negative bacteria, as determined by a radial diffusion assay and colony count assay without hemolytic activity. In addition, we confirmed that scolopendrasin II bound to the surface of bacteria through a specific interaction with lipoteichoic acid and a lipopolysaccharide, which was one of the bacterial cell-wall components. In conclusion, our results suggest that scolopendrasin II may be useful for developing peptide antibiotics.

• Parasites, Hosts and Diseases
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• v.58 no.1
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• pp.99-102
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• 2020

Two-point mutations (V419L and L925I) on the voltage-sensitive sodium channel of bed bugs (Cimex lectularius) are known to confer pyrethroid resistance. To determine the status of pyrethroid resistance in bed bugs in Korea, resistance allele frequencies of bed bug strains collected from several US military installations in Korea and Mokpo, Jeollanamdo, from 2009-2019 were monitored using a quantitative sequencing. Most bed bugs were determined to have both of the point mutations except a few specimens, collected in 2009, 2012 and 2014, having only a single point mutation (L925I). No susceptible allele was observed in any of the bed bugs examined, suggesting that pyrethroid resistance in bed bug populations in Korea has reached a serious level. Large scale monitoring is required to increase our knowledge on the distribution and prevalence of pyrethroid resistance in bed bug populations in Korea. Based on present study, it is urgent to restrict the use of pyrethroids and to introduce effective alternative insecticides. A nation-wide monitoring program to determine the pyrethroid resistance level in bed bugs and to select alternative insecticides should be implemented.

• Biomolecules & Therapeutics
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• v.27 no.2
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• pp.201-209
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• 2019

Mixed lineage leukemia proteins (MLL) are the key histone lysine methyltransferases that regulate expression of diverse genes. Aberrant activation of MLL promotes leukemia as well as solid tumors in humans, highlighting the urgent need for the development of an MLL inhibitor. We screened and isolated MLL1-binding ssRNAs using SELEX (${\underline{S}}ystemic$ ${\underline{E}}volution$ of ${\underline{L}}igands$ by ${\underline{E}}xponential$ enrichment) technology. When sequences in sub-libraries were obtained using next-generation sequencing (NGS), the most enriched aptamers-APT1 and APT2-represented about 30% and 26% of sub-library populations, respectively. Motif analysis of the top 50 sequences provided a highly conserved sequence: 5'-A[A/C][C/G][G/U][U/A]ACAGAGGG[U/A]GG[A/C] GAGUGGGU-3'. APT1, APT2, and APT5 embracing this motif generated secondary structures with similar topological characteristics. We found that APT1 and APT2 have a good binding activity and the analysis using mutated aptamer variants showed that the site information in the central region was critical for binding. In vitro enzyme activity assay showed that APT1 and APT2 had MLL1 inhibitory activity. Three-dimensional structure prediction of APT1-MLL1 complex indicates multiple weak interactions formed between MLL1 SET domain and APT1. Our study confirmed that NGS-assisted SELEX is an efficient tool for aptamer screening and that aptamers could be useful in diagnosis and treatment of MLL1-mediated diseases.

• Preventive Nutrition and Food Science
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• v.17 no.1
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• pp.64-70
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• 2012

Bacilli with fibrinolytic activities were isolated from traditionally-prepared Meju and some of these strains showed strong antifungal activities. One isolate, MJ1-4, showed the strongest antifungal activity. MJ1-4 and other isolates were identified as B. amyloliquefaciens strains by recA gene sequencing and RAPD-PCR results. B. amyloliqufaciens MJ1-4 efficiently inhibited an Aspergillus spp.-producing aflatoxin B1 ($AFB_1$) and a Penicillium spp.-producing ochratoxin (OTA) in addition to other fungi. Antifungal activity of B. amyloliquefaciens MJ1-4 culture reached its maximum (40 AU/mg protein) in LB or TSB medium around 48 hr at $37^{\circ}C$. Antifungal activity of the concentrated culture supernatant was not decreased significantly by protease treatments, implying that the antifungal substance might not be a simple peptide or protein. Considering its antifungal and fibrinolytic activities together, B. amyloliquefaciens MJ1-4 can serve as a starter for fermented soyfoods such as Cheonggukjang and Doenjang.