• Proceedings of the Korean Society for Bioinformatics Conference
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• 2000.11a
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• pp.13-16
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• 2000

Microorganisms have been widely employed for the production of useful bioproducts including primary metabolites such as ethanol, succinic acid, acetone and butanol, secondary metabolites represented by antibiotics, proteins, polysaccharides, lipids and many others. Since these products can be obtained in small quantities under natural condition, mutation and selection processes have been employed for the improvement of strains. Recently, metabolic engineering strategies have been employed for more efficient production of these bioproducts. Metabolic engineering can be defined as purposeful modification of cellular metabolic pathways by introducing new pathways, deleting or modifying the existing pathways for the enhanced production of a desired product or modified/new product, degradation of xenobiotics, and utilization of inexpensive raw materials. Metabolic flux analysis and metabolic control analysis along with recombinant DNA techniques are three important components in designing optimized metabolic pathways, This powerful technology is being further improved by the genomics, proteomics, metabolomics and bioinformatics. Complete genome sequences are providing us with the possibility of addressing complex biological questions including metabolic control, regulation and flux. In silico analysis of microbial metabolic pathways is possible from the completed genome sequences. Transcriptome analysis by employing ONA chip allows us to examine the global pattern of gene expression at mRNA level. Two dimensional gel electrophoresis of cellular proteins can be used to examine the global proteome content, which provides us with the information on gene expression at protein level. Bioinformatics can help us to understand the results obtained with these new techniques, and further provides us with a wide range of information contained in the genome sequences. The strategies taken in our lab for the production of pharmaceutical proteins, polyhydroxyalkanoate (a family of completely biodegradable polymer), succinic acid and me chemicals by employing metabolic engineering powered by genomics, proteomics, metabolomics and bioinformatics will be presented.

• BMB Reports
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• v.46 no.2
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• pp.103-106
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• 2013

Phosphoinositide 3-kinases (PI3Ks) play key roles in synaptic plasticity and cognitive functions in the brain. We recently found that genetic deletion of $PI3K{\gamma}$, the only known member of class IB PI3Ks, results in impaired N-methyl-D-aspartate receptor-dependent long-term depression (NMDAR-LTD) in the hippocampus. The activity of RalA, a small GTP-binding protein, increases following NMDAR-LTD inducing stimuli, and this increase in RalA activity is essential for inducing NMDAR-LTD. We found that RalA activity increased significantly in $PI3K{\gamma}$ knockout mice. Furthermore, NMDAR-LTD-inducing stimuli did not increase RalA activity in $PI3K{\gamma}$ knockout mice. These results suggest that constitutively increased RalA activity occludes further increases in RalA activity during induction of LTD, causing impaired NMDAR-LTD. We propose that $PI3K{\gamma}$ regulates the activity of RalA, which is one of the molecular mechanisms inducing NMDAR-dependent LTD.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.4947-4951
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• 2012

Objective: Lung cancer is a deadly cancer, whose kills more people worldwide than any other malignancy. SLUG (SNAI2, Snail2) is involved in the epithelial mesenchymal transition in physiological and in pathological contexts and is implicated in the development and progression of lung cancer. Methods: We constructed a lentivirus vector with SLUG shRNA (LV-shSLUG). LV-shSLUG and a control lentivirus were infected into the non-small cell lung cancer cell A549 and real-time PCR, Western blot and IHC were applied to assess expression of the SLUG gene. Cell proliferation and migration were detected using MTT and clony formation methods. Results: Real-time PCR, Western Blot and IHC results confirmed down-regulation of SLUG expression by its shRNA by about 80%~90% at both the mRNA and protein levels. Knockdown of SLUG significantly suppressed lung cancer cell proliferation. Furthermore, knockdown of SLUG significantly inhibited lung cancer cell invasion and metastasis. Finally, knockdown of SLUG induced the down-regulation of Bcl-2 and up-regulation of E-cadherin. Conclusion: These results indicate that SLUG is a newly identified gene associated with lung cancer growth and metastasis. SLUG may serve as a new therapeutic target for the treatment of lung cancer in the future.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.6
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• pp.656-661
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• 2017

To develop a highly value-added product from extract from small and damaged sea mussels Mytilus edulis, we prepared two types of sea mussel sauce (MS): bottled (BMS) and retort pouched (RMS). We investigated the processing conditions, quality metrics and flavor compounds in each type of sauce. We found that the most appropriate base formulation for both BMS and RMS consisted of 40.0% SME (Brix $30^{\circ}$), 15.0% sugar, 6.0% salt, 4.0% monosodium glutamate, 4.0% soy sauce, 3.5% starch, 3.0% yeast extract, 3.5% wheat flour and 21.0% water. The crude protein, salinity, volatile basic nitrogen and amino-nitrogen content of the BMS and RMS were 8.7% and 8.8%, 9.3% and 9.2%, 24.9 and 31.4 mg/100 g, and 468.5 and 455.1 mg/100 g, respectively. For comparison, the ranges of these values in commercial oyster sauces (COS) are 4.7-7.5%, 10.7-12.0%, 8.2-12.5 mg/100 g, and 225.7-448.2 mg/100 g, respectively. The total free amino acid content of RMS and Premium COS was 7,215.7 and 6,160.7 mg/100 g, respectively, and the main free amino acids were glutamic acid, taurine, glycine, alanine, arginine, proline and lysine. These results demonstrate that BMS and RMS have favorable organoleptic qualities and good storage stability compared to COS, and are suitable for commercialization as high-flavor seasoning sauces.

• Journal of the Korean Applied Science and Technology
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• v.32 no.1
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• pp.7-15
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• 2015

In this study, the thermal treatment yam (Dioscorea batatas DECNE.) was analyzed for its proximate and nutritional compositions including mineral, vitamin, amino acids and fatty acids. Thermal treatment yam is mainly consisted of carbohydrate (70.3%) with small amounts of crude protein (15.8%), crude ash (5.1%) and crude fat (1.6%). It was found to be a good source of essential minerals such as K (1100.2 mg/100 g), Mg (99.4 mg/100 g), Ca (54.8 mg/100 g) and Na (44.9 mg/100 g) but Zn (4.8 mg/100 g) and Fe (0.2 mg/100g) content was low. Little amounts of vitamin E (8.3 mg/100g), vitamin C (3.5 mg/100g) and vitamin B1 (2.1 mg/100g) could be found. The amino acid analysis revealed that the yam was superior with respect to serine (1454.2 mg%), lysine (684.6 mg%) and histidine (684.6 mg%). Essential amino acids were calculated to be 2849.3 mg%. The amino acid profiles showed that thermal treatment yam is limiting in isoleucine and phenylaline. Linoleic acid was the most predominant fatty acids with the value of 47.3% followed by palmitic acid (24.7%) and oleic acid (12.7%). And the unsaturated fatty acids including oleic acid and linoleic acid were present in big quantities in thermal treatment yam.

• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.778-783
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• 1999

Campylobacter is a pathogen for both humans and animals that can be transferred from animals to humans. Four isolates, which grew under 5-10% $CO_2$ and had small and translucent colonies, were obtained from swine gastric mucosa and characterized using various methods. These bacteria were gram negative, spirally shaped with round ends. One or two non-sheathed polar flagella were observed under electron microscopy. A PCR with species-specific protein (SSP) primers for 16S rRNA gene in Campylobacter produced a typical 462 bp fragment. The isolates had various biochemical and molecular characteristics which differentiated them from other Campylobacters. The isolates were catalase and oxidase positive, urease (rapid) negative, nitrate reduction positive, indoxyl acetate hydrolysis positive, y-glutamyl transpeptidase negative, and alkaline phosphatase negative. All four isolates showed growth at $37^{\circ}C{\;}and{\;}42^{\circ}C{\;}but{\;}not{\;}at{\;}25^{\circ}C$, were resistant to cephalotin and cefoperazone, and susceptible to carbenicillin. The isolates showed various results in the reduction of chloride to triphenyl tetrazolium (TTC) and a susceptibility to nalidixic acid. Western blot analysis of these isolates with antiserum raised against one isolate showed different patterns from those of reference strains. A dendrogram drawn with the RAPD results showed that these isolates belonged to a new Campylobacter spp. group different from those of C. jejuni, C. doylei, C. lari, and C. coli.

• Journal of Korean Neurosurgical Society
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• v.60 no.2
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• pp.130-137
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• 2017

Objective : Autophagy is one of the key responses of cells to programmed cell death. Memantine, an approved anti-dementia drug, has an antiproliferative effect on cancer cells but the mechanism is poorly understood. The aim of the present study was to test the possibility of induction of autophagic cell death by memantine in glioma cell lines. Methods : Glioma cell lines (T-98 G and U-251 MG) were used for this study. Results : The antiproliferative effect of memantine was shown on T-98 G cells, which expressed N-methyl-D-aspartate 1 receptor (NMDAR1). Memantine increased the autophagic-related proteins as the conversion ratio of light chain protein 3-II (LC3-II)-/LC3-I and the expression of beclin-1. Memantine also increased formation of autophagic vacuoles observed under a transmission electron microscope. Transfection of small interfering RNA (siRNA) to knock down NMDAR1 in the glioma cells induced resistance to memantine and decreased the LC3-II/LC3-I ratio in T-98 G cells. Conclusion : Our study demonstrates that in glioma cells, memantine inhibits proliferation and induces autophagy mediated by NMDAR1.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.3
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• pp.370-378
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• 2017

Objective: An experiment was conducted to investigate the effects of a specific mixture of essential oils (MEO), containing thyme, clove and cinnamon EO, on rumen microbial fermentation, nutrient apparent digestibility and blood metabolites in fistulated sheep. Methods: Six sheep fitted with ruminal fistulas were used in a repeated measurement design with two 24-d periods to investigate the effect of adding MEO at 0 (control), 0.8, and 1.6 mL/d on apparent nutrient digestibility, rumen fermentation characteristics, rumen microbial population and blood chemical metabolites. Animals were fed with a 50:50 alfalfa hay:concentrate diet. Results: Ruminal pH, total volatile fatty acids (VFA) concentration, molar proportion of individual VFA, acetate: propionate ratio and methane production were not affected with MEO. Relative to the control, Small peptides plus amino acid nitrogen and large peptides nitrogen concentration in rumen fluid were not affected with MEO supplementation; while, rumen fluid ammonia nitrogen concentration at 0 and 6 h after morning feeding in sheep fed with 1.6 mL/d of MEO was lower (p<0.05) compared to the control and 0.8 mL/d of MEO. At 0 h after morning feeding, ammonia nitrogen concentration was higher (p<0.05) in sheep fed 0.8 mL/d of MEO relative to 1.6 mL/d and control diet. Ruminal protozoa and hyper ammonia producing (HAP) bacteria counts were not affected by addition of MEO in the diet. Relative to the control, no changes were observed in the red and white blood cells, hemoglobin, hematocrit, glucose, beta-hydroxybutyric acid, cholesterol, total protein, albumin, blood urea nitrogen and aspartate aminotransferase and alanine aminotransferase concentration. Apparent total tract digestibility of dry matter, crude proten, organic matter, and neutral detergent fiber were not influenced by MEO supplementation. Conclusion:The results of the present study suggested that supplementation of MEO may have limited effects on apparent nutrient digestibility, ruminal fermentation and protozoa and HAP bacteria count, blood cells and metabolites.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.4
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• pp.670-677
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• 2020

Objective: Interleukin-6 (IL-6) is a T cell-derived B cell stimulating factor which plays an important role in inflammatory diseases. In this study, the pharmacokinetic properties of LMT-28 including physicochemical property, in vitro liver microsomal stability and an in vivo pharmacokinetic study using BALB/c mice were characterized. Methods: LMT-28 has been synthesized and is being developed as a novel therapeutic IL-6 inhibitor. The physicochemical properties and in vitro pharmacokinetic profiles such as liver microsomal stability and Madin-Darby canine kidney (MDCK) cell permeability assay were examined. For in vivo pharmacokinetic studies, pharmacokinetic parameters using BALB/c mice were calculated. Results: The logarithm of the partition coefficient value (LogP; 3.65) and the apparent permeability coefficient values (P_app; 9.7×10^-6 cm/s) showed that LMT-28 possesses a moderate-high cell permeability property across MDCK cell monolayers. The plasma protein binding rate of LMT-28 was 92.4% and mostly bound to serum albumin. The metabolic half-life (t_1/2) values of LMT-28 were 15.3 min for rat and 21.9 min for human at the concentration 1 μM. The area under the plasma drug concentration-time curve and C_max after oral administration (5 mg/kg) of LMT-28 were 302±209 h·ng/mL and 137±100 ng/mL, respectively. Conclusion: These data suggest that LMT-28 may have good physicochemical and pharmacokinetic properties and may be a novel oral drug candidate as the first synthetic IL-6 inhibitor to ameliorate mammalian inflammation.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.14
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• pp.5667-5672
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• 2014

Folate receptor alpha ($FR{\alpha}$) mediates folate uptake by endocytosis, and while folate is essential to DNA methylation and synthesis and may have an important role in proliferating cells. $FR{\alpha}$ is known to be expressed in rapidly proliferating cells, including many cancer cell lines, but there has been no systematic assessment of expression in cervical cancer cell lines. The aim of the present study was to evaluate the effects of $FR{\alpha}$ on proliferation and apoptosis of cervical cells and correlation mechanism. In this study, we investigated the biological function of $FR{\alpha}$ in Hela cells using RNA interference. Cell proliferation was evaluated by Cell Counting Kit-8 (CCK8) assay, while cell cycling and apoptosis were assessed by flow cytometry, mRNA levels by real time-PCR and protein levels of $FR{\alpha}$, c-Fos and c-Jun by Western blotting. The results revealed that $FR{\alpha}$ was highly expressed in Hela cells and its silencing with a small interfering RNA (siRNA) inhibited cell proliferation and induced cell apoptosis, arresting the cell cycle in G0/G1 stages while decreasing the proportion in S and G2/M stages, and suppressed the expression levels of c-Fos and c-Jun. In conclusion, the results of this study indicated that $FR{\alpha}$ down-regulation might be capable of suppressing cervical cancer cell proliferation and promoting apoptosis. It suggested that $FR{\alpha}$ might be a novel therapeutic target for cervical cancer.