• Development and Reproduction
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• v.16 no.4
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• pp.301-307
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• 2012

Olive flounder Paralichthys olivaceus is one of the most widely cultured fish species in Korea. Although olive flounder receive attention from aquaculture and fisheries and extensive research has been conducted eye morphological change in metamorphosis, but little information was known to molecular mechanism and gene expression of eye development- related genes during the early part of eye formation period. For the reason of eyesight is the most important sense in flounder larvae to search prey, the screening and identification of expressed genes in the eye will provide useful insight into the molecular regulation mechanism of eye development in olive flounder. Through the search of an olive flounder DNA database of expressed sequence tags (EST), we found a partial sequence that was similar to crystallin beta A1 and gamma S. Microscopic observation of retinal formation correspond with the time of expression of the crystallin beta A1 and gamma S gene in the developmental stage, these result suggesting that beta A1 and gamma S play a vital role in the remodeling of the retina during eye development. The expression of crystallin beta A1 and gamma S were obviously strong in eye at all tested developing stage, it is also hypothesized that crystallin acts as a molecular chaperone to prevent protein aggregation during maturation and aging in the eye.

• Journal of Microbiology and Biotechnology
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• v.10 no.6
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• pp.764-769
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• 2000

The lipase gene(lip) from Bacillus stearothermophilus was recombined in vitro by utilizing the DNA shuffling technique. After four rounds of shuffling, transformation, and screening based on the initial rate of clear zone formation on a tricaprylin plate, a clone (M10) was isolated, the cell extract of which showed about 2.8-fold increased lipase activity. The DNA sequence of the mutant lipase gene (m10) showed 3 base changes, resulting in two cryptic mutations and one amino acid substitution: S113($AGC{\rightarrow}AGT$), L252 ($TTG{\rightarrow}TTA$), and G275E ($GGA{\rightarrow}GAA$). SDS-PAGE analysis revealed that the increased enzyme activity observed in M10 was partly caused by high expression of the m10 lipase gene. The amount of the expressed G275E lipase was estimated to comprise as much as 41% of the total soluble proteins of the cell. The maximum velocity ($V_{max}$) of the purified mutant enzyme for the hydrolysis of olive oil was measured to be 3,200 U/mg, which was 10% higher than that of the parental (WT) lipase (2,900 U/mg). Its optimum temperature for the hydrolysis of olive oil was $68^{\circ}C$ and it showed a typical $Ca^{2+}$-dependent thermostability, properties fo which were the same as those of the WT lipase. However, the mutant enzyme exhibited a high enantiospecificity towards (S)-naproxen compared with the WT lipase. In addition, it showed increased hydrolytic activity towards triolein, tricaprin, tricaprylin, and tricaproin.

• Journal of Pharmacopuncture
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• v.8 no.1
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• pp.31-40
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• 2005

Objectives : It has long been known about the osteogenic effect of CTF-HAS on bone tissues. However, it has not been determined the effect of CTF-HAS on cancer cells. The purpose of this study is to screen the CTF-HAS mediated differentially expressed genes in cancer cells such as SNU484 gastric cancer cell lines. Oligonucleotide microarray approach were employed to screen the differential expression genes. Methods : CTF-HAS was prepared by boiling and stored at $-70^{\circ}C$ until use. Cells were treated with various concentrations of CTF-HAS(0.1, 0.5, 1.5, 10, 20mg/ml) for 24 h. Cytotoxicity was tested by MTT assay. To screen the differentially expressed genes in cancer cells, cells were treated with 1.5mg/ml of CTF-HAS. For oligonucleotide microarry assay, total RNA was used for gene expression analysis using oligonucleotide genechip (Human genome U133 Plus 2.0., Affimatrix Co.). Results : It has no cytotoxic effects on HepG2 cells in all concentration (0.1, 0.5, 1.5, 10,20mg/ml). More than twofold up-regulated genes were 5 genes. The number of more than twofold down-regulated genes was 10. Discussion : This study showed the screening of CTF-HAS mediated differentially regulated genes using combined approaches of oligonucleotide microarray. The screened genes will be used for the better understanding in therapeutic effect of CTF-HAS on cancer field.

• BMB Reports
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• v.38 no.1
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• pp.17-23
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• 2005

During the screening of xylanolytic enzymes from locally isolated fungi, one strain BCC14405, exhibited high enzyme activity with thermostability. This fugal strain was identified as Aspergillus cf. niger based on its morphological characteristics and internal transcribed spacer (ITS) sequences. An enzyme with xylanolytic activity from BCC14405 was later purified and characterized. It was found to have a molecular mass of ca. 21 kDa, an optimal pH of 5.0, and an optimal temperature of $55^{\circ}C$. When tested using xylan from birchwood, it showed $K_m$ and $V_{max}$ values of 8.9 mg/ml and 11,100 U/mg, respectively. The enzyme was inhibited by $CuSO_4$, EDTA, and by $FeSO_4$. The homology of the 20-residue N-terminal protein sequence showed that the enzyme was an endo-1,4-$\beta$-xylanase. The full-length gene encoding endo-1,4-$\beta$-xylanase from BCC14405 was obtained by PCR amplification of its cDNA. The gene contained an open reading frame of 678 bp, encoding a 225 amino acid protein, which was identical to the endo-1,4-$\^{a}$-xylanase B previously identified in A. niger.

• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.1052-1056
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• 2004

A secretion signal sequence-selection vector (pGS40) was constructed based on an $\alpha$-amylase gene lacking a secretion signal and employed for selecting secretion signals from Lactococcus lactis ssp. cremoris LM0230 chromosomal DNA. Six fragments were identified based on their ability to restore $\alpha$-amylase secretion in E. coli, and among these, a fragment, S405, conferred the highest secretion activity (84%) in E. coli. Meanwhile, S407, which conferred poor secretion activity in E. coli, was quite active in L. lactis. The results suggested that the efficiency of a secretion signal depended on the host. All six fragments had an open reading frame (ORF) fused to the reporter gene, and the potential Shine-Dalgamo (SD) sequence and putative promoter sequences were located upstream of the ORF. Deduced amino acid sequences from the six fragments did not show any homology with known secretion signals. However, they contained three distinguished structural features and cleavage sites, commonly found among typical secretion signals. The characterized secretion signals could be useful for the construction of food-grade secretion vectors and gene expression in LAB.

• Journal of Microbiology and Biotechnology
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• v.17 no.6
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• pp.905-912
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• 2007

A novel ${\beta}-glucosidase$ gene, bglA, was isolated from uncultured soil bacteria and characterized. Using genomic libraries constructed from soil DNA, a gene encoding a protein that hydrolyzes a fluorogenic analog of cellulose, 4-methylumbelliferyl ${\beta}-D-cellobioside$ (MUC), was isolated using a microtiter plate assay. The gene, bglA, was sequenced using a shotgun approach, and expressed in E. coli. The deduced 55-kDa amino acid sequence for bglA showed a 56% identity with the family 1 glycosyl hydrolase Chloroflexus aurantiacus. BglA included two conserved family 1 glycosyl hydrolase regions. When using $p-nitrophenyl-{\beta}-D-glucoside$ (pNPG) as the substrate, the maximum activity of the purified ${\beta}-glucosidase$ exhibited at pH 6.5 and $55^{\circ}C$, and was enhanced in the presence of $Mn^{2+}$. The $K_m\;and\;V_{max}$ values for the purified enzyme with pNPG were 0.16 mM and $19.10{\mu}mol/min$, respectively. The purified BglA enzyme hydrolyzed both pNPG and $p-nitrophenyl-{\beta}-D-fucoside$. The enzyme also exhibited substantial glycosyl hydrolase activities with natural glycosyl substrates, such as sophorose, cellobiose, cellotriose, cellotetraose, and cellopentaose, yet low hydrolytic activities with gentiobiose, salicin, and arbutin. Moreover, BglA was able to convert the major ginsenoside $Rb_1$ into the pharmaceutically active minor ginsenoside Rd within 24 h.

• Journal of Microbiology and Biotechnology
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• v.24 no.9
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• pp.1260-1268
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• 2014

Screening of a gene library from Paenibacillus sp. PBS-2 generated in Escherichia coli led to the identification of a clone with lipolytic activity. Sequence analysis showed an open reading frame encoding a polypeptide of 378 amino acid residues with a predicted molecular mass of 42 kDa. The esterase displayed 69% and 42% identity with the putative ${\beta}$-lactamases from Paenibacillus sp. JDR-2 and Clostridium sp. BNL1100, respectively. The esterase contained a Ser-x-x-Lys motif that is conserved among all ${\beta}$-lactamases found to date. The protein PBS-2 was produced in both soluble and insoluble forms when E. coli cells harboring the gene were cultured at $18^{\circ}C$. The enzyme is a serine protein and was active against p-nitrophenyl esters of $C_2$, $C_4$, $C_8$, and $C_{10}$. The optimum pH and temperature for enzyme activity were pH 9.0 and $30^{\circ}C$, respectively. Relative activity of 55% remained at up to $5^{\circ}C$ with an activation energy of 5.84 kcal/mol, which indicates that the enzyme is cold-adapted. Enzyme activity was inhibited by $Cd^{2+}$, $Cu^{2+}$, and $Hg^{2+}$ ions. As expected for a serine esterase, activity was inhibited by phenylmethylsulfonyl fluoride. The enzyme was remarkably active and stable in the presence of commercial detergents and organic solvents. This cold-adapted esterase has potential as a biocatalyst and detergent additive for use at low temperatures.

• Mycobiology
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• v.43 no.1
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• pp.31-36
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• 2015

We have previously isolated ${\varepsilon}$-COP, the ${\alpha}$-COP interactor in COPI of Aspergillus nidulans, by yeast two-hybrid screening. To understand the function of ${\varepsilon}$-COP, the $aneA^+$ gene for ${\varepsilon}$-COP/AneA was deleted by homologous recombination using a gene-specific disruption cassette. Deletion of the ${\varepsilon}$-COP gene showed no detectable changes in vegetative growth or asexual development, but resulted in decrease in the production of the fruiting body, cleistothecium, under conditions favorable for sexual development. Unlike in the budding yeast Saccharomyces cerevisiae, in A. nidulans, over-expression of ${\varepsilon}$-COP did not rescue the thermo-sensitive growth defect of the ${\alpha}$-COP mutant at $42^{\circ}C$. Together, these data show that ${\varepsilon}$-COP is not essential for viability, but it plays a role in fruiting body formation in A. nidulans.

• The Journal of Korean Medicine
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• v.29 no.3
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• pp.88-99
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• 2008

Objectives: In order to identify the anti-inflammatory and analgesic properties of Salvia miltiorrhiza (Dan-Sam), widely used in Korean traditional medicine, an in vitro screening system was designed using pGL3, a luciferase reporter vector, and the tumor necrosis factor (TNF)-${\alpha}$ and cyclooxygenase (COX)-2 as target genes. Methods: The promoter regions of each gene were generated by PCR using the human chromosome as template DNA, and inserted into pGL3 vector with Kpn I and Hind III. The final construct was transfected into human myelomonocytic leukemia cells (U-937) that could be differentiated and activated by phorbol 12-myristate 13-acetate (PMA) or lipopolysaccharide (LPS). Using this system, the anti-inflammatory and analgesic effects of several herbal extracts regarded to have the medicinal effects of diminishing body heat and complementing Qi were tested. The chemicals PD98059 and berberine chloride were used as controls of the transcriptional inhibitors of TNF-${\alpha}$ and COX-2, respectively. Results: Salvia miltiorrhiza (Dan-Sam) demonstrated significant decrease of TNF-${\alpha}$ and COX-2 mRNA in the in vitro assay system. In MTT assay, Salvia miltiorrhiza (Dan-Sam) did not significantly inhibit the survival and proliferation of human myelomonocytic leukemia cells (U-937). Conclusions: Salvia miltiorrhiza (Dan-Sam) was found to exhibit the significant medicinal properties of anti-inflammatory and analgesic effects.

• Molecular & Cellular Toxicology
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• v.2 no.2
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• pp.114-119
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• 2006

Benzo[a]pyrene is a representative ecotoxicant in marine environment and a model compound of polycyclic aromatic hydrocarbons, which has an ability to bioaccumulate in aquatic organisms. This study aimed to identify molecular biomarkers suitable for assessing environmental pollution using a microarray technique. We examined the effects of benzo[a]pyrene on gene expressions in the rockfish, Sebastes schlegeli. We constructed the subtractive cDNA library with hepatic RNA from benzo[a]pyrene-exposed and non-exposed control fish. From the library 10,000 candidate clones were selected randomly and cDNA microarray was constructed. We determined benzo[a]pyrene-responsive genes using a high-density microarray. Statistical analysis showed that approximately 400 genes are significantly induced or reduced by benzo[a]pyrene treatment ($2\;{\mu}m$). Especially gene expression changes of 4 candidate clones among the up- or down-regulated genes were investigated in 6, 12 and 24 hr BaP-exposed fish groups. Many methods have been developed to monitor marine environmental status, which depend on quantifying the levels of the toxic components in polluted seawater or on ecological accessing, such as species diversity or richness. However, those methods could not provide information on physiological or genetic changes induced by such environmental stresses. Comparing with the conventional methods, these data will propose that benzo[a]pyrene-responsive genes can be useful for biological risk assessment of polycyclic aromatic hydrocarbons on marine organism at molecular level.