• KSBB Journal
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• v.16 no.2
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• pp.188-199
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• 2001

A gene encoding the dextransucrase(dsCB) that synthesizes mostly $\alpha-(1\rightarrow6)$ linked dextran with low amount(10%) of $\alpha-(1\rightarrow3)$ branching was cloned and sequenced from Leuconostoc mesenteroides B-742CB. The 6.1 kbp DNA fragment carrying dsCB showed one open reading frame(ORF) composed of 4,536bp. The deduced amino acid sequence shows that it begins from the start codon(ATG) at position 698 of the cloned DNA fragment and extends to the termination condon(TAA) at position 5,223. The enzyme is consisted of 1,508 amino acids and has an calculated molecular mass of 168.6kDa. This calculated Mw was in good agreement with an activity band of 170kDa on non-denaturing SDS-PAGE. A recombinant E. coli DH5 $alpha$ harboring pDSCB produced extracellular dextransucrase in 2% sucrose medium, and synthesized both soluble and insoluble dextran. To compare the properties of enzyme with B-742CB dextransucrase, the acceptor reaction, hydrolysis of dextran and methylation were performed. The expressed enzyme showed the same properties as B-742CB dextransucrease, but its ability to synthesize $\alpha-(1\rightarrow3)$ branching was lower than that of B-742CB dextransucrase. In order to identify the critical amino acid residues known as conserved regions related to catalytic activity, Asp-492 was replaced with Asn. D492N resulted in a 1.6 fold decrease in specific activity.

• IMMUNE NETWORK
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• v.19 no.1
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• pp.5.1-5.12
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• 2019

Autophagy is a homeostatic mechanism that discards not only invading pathogens but also damaged organelles and denatured proteins via lysosomal degradation. Increasing evidence suggests a role for autophagy in inflammatory diseases, including infectious diseases, Crohn's disease, cystic fibrosis, and pulmonary hypertension. These studies suggest that modulating autophagy could be a novel therapeutic option for inflammatory diseases. Eosinophils are a major type of inflammatory cell that aggravates airway inflammatory diseases, particularly corticosteroid-resistant inflammation. The eosinophil count is a useful tool for assessing which patients may benefit from inhaled corticosteroid therapy. Recent studies demonstrate that autophagy plays a role in eosinophilic airway inflammatory diseases by promoting airway remodeling and loss of function. Genetic variant in the autophagy gene ATG5 is associated with asthma pathogenesis, and autophagy regulates apoptotic pathways in epithelial cells in individuals with chronic obstructive pulmonary disease. Moreover, autophagy dysfunction leads to severe inflammation, especially eosinophilic inflammation, in chronic rhinosinusitis. However, the mechanism underlying autophagy-mediated regulation of eosinophilic airway inflammation remains unclear. The aim of this review is to provide a general overview of the role of autophagy in eosinophilic airway inflammation. We also suggest that autophagy may be a new therapeutic target for airway inflammation, including that mediated by eosinophils.

• Microbiology and Biotechnology Letters
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• v.33 no.2
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• pp.84-89
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• 2005

Phosphomannomutase (PMM) is a key enzyme in prokaryotes and eukaryotes, which catalyzes the conversion of ${\alpha}$-D-mannose 6-phosphate to ${\alpha}$-D-mannose 1-phosphate. The latter is the substrate for the synthesis of GDP-mannose, which serves as the mannosyl donor for many metabolic pathways in the cells. We report here on the isolation of a gene from a genomic library of Sphingomonas chungbukensis DJ77, the pmmC gene encoding phosphomannomutase. The gene was cloned into E. coli expression vector, and the sequence was analyzed. The ribosomal binding site GGAAG lays 5 bp upstream of the ORF of 750 bp, which is initiated by ATG codon and terminated by TAG. The predicted sequence of the enzyme consists of 249 amino acids with a molecular mass of 27.4 kDa and showed $86.9\%$ similarity to that of eukaryotic phosphomannomutase after bioinformatical analyses with the conserved domain search of NCBI. The purified gene product revealed the activity of phosphomannomutase. In conclusion, we confirmed that pmmC gene encodes phosphomannomutase actually.

• Journal of Life Science
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• v.21 no.3
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• pp.400-405
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• 2011

Autophagy, a highly conserved mechanism of internal quality control, is essential for the maintenance of cellular homeostasis and for the orchestration of an efficient cellular response to stress. During aging, the efficiency of autophagic degradation declines and intracellular waste products accumulate. Therefore, the aim of this study is to investigate the effects of exercise on autophagic response in skeletal muscle. Twenty-four Young (4 month) and Old (12 month) ICR-type white male mice were divided into a control group (CON: n=6) and exercise training group (Tr: n=6) after an adaptation period of 1 week. Exercise consisted of treadmill running at 16.4 m/min with a 4% incline, 40 min/day and 5 days/week for 8 weeks. Cervical dislocation was performed at 48 hours after the last round of exercise, after which the gastrocnemius skeletal muscle were immediately collected. The results of verifying autophagy formation showed that the Sarcopenia index was decreased in the Old mice compared to the Young. However, it increased with exercise training in the Old. Lipidation LC3-II, Becline-1, and Atg7 were decreased in the Old mice compared to the Young. However, Lipidation LC3-II was significantly increased in the trained Old mice (Young:1 Vs Old:$1.32{\pm}0.042$, p<0.05). Based on these data, we suggest that autophagy regulatory events are the attenuated in Old mice, but that they are enhanced with exercise training.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.7
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• pp.1055-1059
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• 2003

Keratins, the constituents of epithelial intermediate filaments, are precisely regulated in a tissue and development specific manner. There are two types of keratin in bovine. The type I is acidic keratin and the type II is neutral/basic keratin. 1.5 kb of 5' flanking sequence of Korean cattle Keratin IV gene, type II keratin (59 kDa), was cloned and sequenced. A symmetrical motif AApuCCAAA are located in a defined region upstream of the TATA box. Proximal SP1, AP1, E-box and CACC elements as the major determinants of transcription are identified. When it was compared to the bovine sequence from -600 bp to ATG upstream, the homology was 97% in nucleotide sequence. Several A and T sequences, located in the promoter region, are deleted in the Korean cattle. An expression vector consisted of Korean cattle Keratin IV gene promoter/SV40 large T antigen was transfected to HaCaT cell (Epithelial keratinocyte). The transformed HaCaT cells showed active proliferation when treated with PDGF (Platelet-derived growth factor) in 0.3% soft agar compared to control cells. These results indicate that Korean cattle Keratin IVgene promoter can be used as a promoter for transfection into epithelial cell.

• Journal of Microbiology and Biotechnology
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• v.10 no.5
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• pp.700-706
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• 2000

Iron- and zinc-containing superoxide dismutase (FeZnSOD) and nickel-containing superoxide dismutase (NiSOD) are cytoplamic enzymes in Streptomyces griseus. The sodF gene coding for FeZnSOD was cloned from genomic Southern hybridization analysis with a 0.5-kb DNA probe, which was PCR-amplified with facing primers corresponding to the N-terminal amino acid of the purified FeZnSOD of S. griseus and a C-terminal region which is conserved among bacterial FeSODs and MnSODs. The sodF open reading frame (ORF) was comprised of 213 amino acid (22,430 Da), and the deduced sequence of the protein was highly homologous (86% identity) to that of FeZnSOD of Streptomyces coelicolor. The FeZnSOD expression of exponentially growing S. griseus cell was approximately doubled as the cell growth reached the early stationary phase. The growth-associated expression of FeZnSOD was mainly controlled at the transcriptional level, and the regulation was exerted through the 110 bp regulatory DNA upstream from the ATG initiation codon of the sodF gene.

• Biomolecules & Therapeutics
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• v.27 no.5
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• pp.484-491
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• 2019

Glioblastoma is the most aggressive common brain tumor in adults. Curcumin, from Curcuma longa, is an effective antitumor agent. Although the same proteins control both autophagy and cell death, the molecular connections between them are complicated and autophagy may promote or inhibit cell death. We investigated whether curcumin affects autophagy, which regulates curcumin-mediated tumor cell death in A172 human glioblastoma cells. When A172 cells were incubated with $10{\mu}M$ curcumin, autophagy increased in a time-dependent manner. Curcumin-induced cell death was reduced by co-incubation with the autophagy inhibitors 3-methyladenine (3-MA), hydroxychloroquine (HCQ), and LY294002. Curcumin-induced cell death was also inhibited by co-incubation with rapamycin, an autophagy inducer. When cells were incubated under serum-deprived medium, LC3-II amount was increased but the basal level of cell viability was reduced, leading to the inhibition of curcumin-induced cell death. Cell death was decreased by inhibiting curcumin-induced autophagy using small interference RNA (siRNA) of Atg5 or Beclin1. Therefore, curcumin-mediated tumor cell death is promoted by curcumin-induced autophagy, but not by an increase in the basal level of autophagy in rapamycin-treated or serum-deprived conditions. This suggests that the antitumor effects of curcumin are influenced differently by curcumin-induced autophagy and the prerequisite basal level of autophagy in cancer cells.

• Microbiology and Biotechnology Letters
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• v.13 no.1
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• pp.19-25
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• 1985

The HIS5 gene of Saccharomyces cerevisiae host was encoded histidinol phosphate aminotransferase(E.C.: 2.6. 1.9). The HIS5 gene of Saccharomyces cerevisiae was cloned on plasmid pSH 530. This gene mighted be transcripted from a promoter of yeast gene both in E. coli and yeast hosts. We have determined the nucleotide sequence of the yeast HIS5 gene and its 5' and 3' flanking sequences. There are no large differences between the relative levels of HIS5 mRNA molecules with different 5' termini in represent and derepressed cell. In the DNA sequence upstream from the 5' termini of HIS5 mRNA we have found live closely related copies of a 9 base pair sequence. The sequence is also repeated in the 5' noncoding regions of HIS1, HIS3, HIS4, HIS5 and TRP5. Closely related sequence are not found flanking repeat sequence plays a role in the regulation of amino acid biosynthetic genes subject to the general amino acid control.

• Biomolecules & Therapeutics
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• v.25 no.3
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• pp.315-320
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• 2017

We investigated the role of autophagy in SNUC5/5-FUR, 5-fluorouracil (5-FU) resistant SNUC5 colon cancer cells. SNUC5/5-FUR cells exhibited low level of autophagy, as determined by light microscopy, confocal microscopy, and flow cytometry following acridine orange staining, and the decreased level of GFP-LC3 puncta. In addition, expression of critical autophagic proteins such as Atg5, Beclin-1 and LC3-II and autophagic flux was diminished in SNUC5/5-FUR cells. Whereas production of reactive oxygen species (ROS) was significantly elevated in SNUC5/5-FUR cells, treatment with the ROS inhibitor N-acetyl cysteine further reduced the level of autophagy. Taken together, these results indicate that decreased autophagy is linked to 5-FU resistance in SNUC5 colon cancer cells.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.5
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• pp.513-523
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• 2018

The tumor microenvironment greatly influences cancer cell characteristics, and acidic extracellular pH has been implicated as an essential factor in tumor malignancy and the induction of drug resistance. Here, we examined the characteristics of gastric carcinoma (GC) cells under conditions of extracellular acidity and attempted to identify a means of enhancing treatment efficacy. Acidic conditions caused several changes in GC cells adversely affecting chemotherapeutic treatment. Extracellular acidity did inhibit GC cell growth by inducing cell cycle arrest, but did not induce cell death at pH values down to 6.2, which was consistent with down-regulated cyclin D1 and up-regulated p21 mRNA expression. Additionally, an acidic environment altered the expression of atg5, HSPA1B, collagen XIII, collagen XXAI, slug, snail, and zeb1 genes which are related to regulation of cell resistance to cytotoxicity and malignancy, and as expected, resulted in increased resistance of cells to multiple chemotherapeutic drugs including etoposide, doxorubicin, daunorubicin, cisplatin, oxaliplatin and 5-FU. Interestingly, however, acidic environment dramatically sensitized GC cells to apoptosis induced by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Consistently, the acidity at pH 6.5 increased mRNA levels of DR4 and DR5 genes, and also elevated protein expression of both death receptors as detected by immunoblotting. Gene silencing analysis showed that of these two receptors, the major role in this effect was played by DR5. Therefore, these results suggest that extracellular acidity can sensitize TRAIL-mediated apoptosis at least partially via DR5 in GCs while it confers resistance to various type of chemotherapeutic drugs.