• Korean Journal of Animal Reproduction
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• v.18 no.3
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• pp.199-206
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• 1994

We present here a new PCR-based cloning technique that allows the different PCR products during mouse embryogenesis. Recently, mRNA differential display described by Liang & Pardee (Science 257, 1992) and re-confirmed by Zimermann & Schultz (PNAS 91,1994). This method will detect the appropriate changes in the temporal patterns of expression or in the transition from maternal control to zygotic control as well as the functional difference of embryo with polyspermy or monospermy, the difference of expression between successfully hatched blastocyst and blastocyst failed to hatching, response to agents, and cell cycle regulation. By this methods, we have cloned an eDNA, which showed mouse 2 cell specific expression. Genomic DNA digested with EcoRI showed approximately 15 kb and then showed higher expression in fetal liver rather than adult liver. Furthermore, this gene is likely to have 2 mRNA by alternative splicing.

• Korean Journal of Agricultural Science
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• v.15 no.2
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• pp.153-163
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• 1988

This experiment was carried out to obtain the thermophilic fungus producing amylase and to investigate properties of the amylase. The selected strain, L-11 was obtained from soil in the vicinity of a hot spring and identified as Mocor sp.. And then the conditions for enzyme production in wheat bran cultures and properties of the crude enzyme were investigated. Furthermore, the enzyme was purified and the characteristics of purified enzyme were studied. The results obtained were as follows: 1. On the wheat bran medium added 80-100% water, amylase was effectively produced by the selected strain, L-11 for 48 hrs incubation at $50^{\circ}C$. 2. When the crude enzyme solution of the strain L-11 was passed through DEAE-Sephadex A-50 column chromatography, two peaks having amylase activity were obtained, and one peak was that of the main enzyme (enzyme of B peak). 3. The purified enzyme (enzyme of B peak) was recognized as single protein band on polyacrylamide disc gel electrophoresis. 4. In the hydrolysis reaction of soluble starch by the enzyme of main amylase, oligosaccharides produced at early stage were maltose and maltotriose mainly and procedure of the reaction maltose amount of maltose and glucose was increased. 5. The strain L-11 was recognized as a special strain producing ${\alpha}-amylase$ mainly and scarcely glucoamylase. 6. The optimum pH, optimum temperature, pH stability, and temperature stability of ${\alpha}-amylase$ were pH 4.0, $60-65^{\circ}C$, pH 4.0-9.0, and below$70^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.27 no.3
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• pp.271-280
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• 1995

These studies examined the production of oligosaccharides by ${\beta}-galactosidase$originated from Aspergillus oryzae and Kluyveromyces fragilis mixed. In addition, heat resistance and acid stability of transgalactosylated oligosaccharides were measured. When ${\beta}-galactosidase$ from A. oryzae, K. fragilis and mixed ${\beta}-galactosidase$ were added to 30%(w/v) lactose solution, maximum production of transgalactosylated oligosaccharides were 26.9%, 37.05 and 27.2%, respectively. The ratios of disacchride, trisacchride and tetrasaccharide in transgalactosylated oligosaccharides were 20.5 : 5.4 : 0.6, 20.4 : 10.5 : 4.2 and 21.0 : 4.1 : 1.9, respectively. Nine different oligosaccharides were recovered with 30% and 40% ethanol fractions. When the 30% ethanol fraction was treated at $150^{\circ}C$ for 10 min more than 90% of oligosaccharides remained stable. More than 90% of the oligosaccharides were stable at $130^{\circ}C$ for 3 min with pH 3.0, whereas there of Kluyveromyces was more than 90% with pH 3.5.

• Microbiology and Biotechnology Letters
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• v.39 no.3
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• pp.245-251
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• 2011

[ ${\alpha}$ ]Galactosidase was purified from a culture filtrate of Mortierella sp. by CM-sephadex C-50, and subsequent Sephadex G-100 column chromatography. The final preparation thus obtained showed a single band on SDS-polyacrylamide gel electrophoresis. The molecular weight was determined to be 56 kDa. $Gal^3Man^4$ ($6^3$-mono-O-${\alpha}$-D-galactopyranosyl-4-O-${\beta}$-D-mannotetraose), $Gal^{2,3}Man_5$ ($6^{2,3}$-di-O-${\alpha}$-D-galactopyranosyl-4-O-${\beta}$-D-mannopentaose), $Gal_2Man_3$ ($6^2$-mono-O-${\alpha}$-D-galactopyranosyl-4-O-${\beta}$-D-mannotriose), $Gal^2Man_6$ ($6^2$-mono-O-${\alpha}$-D-galactopyranosyl-4-O-${\beta}$-D-mannohexaose) and $Gal^2Man_5$ ($6^2$-mono-O-${\alpha}$-D-galactopyranosyl-4-O-${\beta}$-D-mannopentaose), prepared from 3 types of microbial ${\beta}$-mannnanase, were used as substrates. $Gal^3Man_4$ and $Gal^2Man_3$ had a stubbed ${\alpha}$-galactosyl residue on the $2^{nd}$ and $3^{rd}$ mannose from the reducing end of mannotetraose and mannotriose, thus ${\alpha}$-galactosidase showed a preference for stubbed ${\alpha}$-galactosyl residue. ${\alpha}$-Galactosidase hydrolyzed $Gal^3Man_4$ more rapidly than $Gal^2Man_3$. However, ${\alpha}$-galactosidase hardly acted on $Gal^{2,3}Man_5$, $Gal^2Man_6$ or $Gal^2Man_5$. The enzyme hydrolyzed melibiose to galactose and glucose, raffinose to galactose and sucrose, and also stachyose to galactose and raffinose.

• Korean Journal of Food Science and Technology
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• v.22 no.3
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• pp.307-311
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• 1990

Raw soy sauce and raw soy sauce added with several Maillard reactants (glucose, xylose, glycine), preheated or unheated, were stored under aerobic or anaerobic conditions to investigate the effect of oxygen on the browning of soy sauce. All experimental groups, except xylose-added groups, stored under aerobic condition browned about 2.5 times as much as those stored under anaerobic condition. Soy sauce added with xylose stored under aerobic condition browned about 1.5 times as much as that stored under anaerobic condition. Contrarily, there have been no consistent differences in the browning except the initial 10% difference between preheated and unheated samples, implying that biological (microbiological and enzymatic) browning was not important in the browning of commercially brewed soy sauce.

• Journal of Life Science
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• v.18 no.1
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• pp.75-83
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• 2008

This studies were designed to elucidate whether inhibitors of topoisomerase regulate function and activity of topoisomerase, and gene expression in HL-60 human leukemia cells. HL-60 cells were treated with 10-hydroxycamptothecin or doxorubicin, total RNA was isolated, and expressed genes were investigated with human oligonucleotide microarray containing 10K gene, respectively. Expression profiles of the human leukemia HL-60 cells treated with 10-hydroxycamptothecin (10-CIT) or doxorubicin associated with signal transduction,. cell adhesion, cell cycle, cell growth, cell proliferation, cell differentiation, transcription and immune response, especially genes related with transcription and cell growth. In HL-60 cells treated with 10-CPT, the expression of topoisomerase III${\alpha}$, III${\beta}$ and I gene from oligo chip microarray analysis were increased over, but the expression of topoisomerase II${\alpha}$ and II${\beta}$ gene were decreased over. In contrast, the expression of topoisomerase II${\alpha}$ and II${\beta}$ gene were increased over in HL-60 cells treated with doxorubicin, whereas the expression of topoisomerase III${\alpha}$ and III${\beta}$ mRNA remained no significant change. These results suggest that these data may be useful for novel therapeutic markers.

• Korean Journal of Microbiology
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• v.41 no.1
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• pp.1-7
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• 2005

Methylophaga aminosulfidovorans SK1 (KCTC 10323 BP) can utilize trimethylamine as a sole carbon, nitrogen, and energy source. The bacterial flavin-containing monooxygenase (bFMO) gene was identified in the strain and the recombinant enzyme expressed in E. coli oxidized trimethylamine. To study the function and regulation of the bfmo, over 8,000 nucleotide sequences of the neighboring regions including the bfmo were determined. Three open reading frames proceeding to the bfmo gene encoded analogues to highly conserved nitrate/nitrite sensing two-component system regulators and a methyl accepting protein. Two small open reading frames just downstream of the bfmo gene showed no similar proteins of known functions but the sequences were conserved among other bacteria. Reverse transcription-polymerase chain reaction analysis showed that the six putative genes consisted of three transcription units. The three regulatory genes located upstream of the bfmo gene formed two separate transcription units. The bfmo and the two downstream genes were transcribed from a single promoter.

• Journal of Life Science
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• v.33 no.8
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• pp.651-662
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• 2023

Peroxisomes, known as microbodies, are a class of morphologically similar subcellular organelles commonly found in most eukaryotic cells. They are 0.2~1.8 ㎛ in diameter and are bound by a single membrane. The matrix is usually finely granular, but occasionally crystalline or fibrillary inclusions are observed. They characteristically contain hydrogen peroxide (H₂O₂) generating oxidases and contain the enzyme catalase, thus confining the metabolism of the poisonous H₂O₂ within these organelles. Therefore, the eukaryotic organelles are greatly dynamic both in morphology and metabolism. Plant peroxisomes, in particular, are associated with numerous metabolic processes, including β-oxidation, the glyoxylate cycle and photorespiration. Furthermore, plant peroxisomes are involved in development, along with responses to stresses such as the synthesis of important phytohormones of auxins, salicylic acid and jasmonic acids. In the past few decades substantial progress has been made in the study of peroxisome biogenesis in eukaryotic organisms, mainly in animals and yeasts. Advancement of sophisticated techniques in molecular biology and widening of the range of genomic applications have led to the identification of most peroxisomal genes and proteins (peroxins, PEXs). Furthermore, recent applications of proteome study have produced fundamental information on biogenesis in plant peroxisomes, together with improving our understanding of peroxisomal protein targeting, regulation, and degradation. Nonetheless, despite this progress in peroxisome development, much remains to be explained about how peroxisomes originate from the endoplasmic reticulum (ER), then assemble and divide. Peroxisomes perform dynamic roles in many phases of plant development, and in this review, we focus on the latest progress in furthering our understanding of plant peroxisome functions, biogenesis, and dynamics.

• Clinical and Experimental Pediatrics
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• v.48 no.11
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• pp.1252-1255
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• 2005

Abnormalities in the levels of thyroxine-binding globulin (TBG) are not associated with clinical disease and they do not require treatment. Congenital TBG deficiency is inherited in an X-linked manner. To date, some complete and partial TBG variants and one polymorphism have been identified by analysis of the TBG gene. Two male neonates were referred to us because of their low $T_4$ levels that were noted on the neonatal screening test. They showed normal levels of free $T_4$ and TSH. Their serum TBG was not detectable and those values of their parents were within the normal ranges. The genomic DNA was extracted from their white blood cells and the four coding exons of the TBG gene were amplified by using polymerase chain reaction. Sequencing of the four coding regions and all the intron/exon junctions revealed a single nucleotide deletion of the first base of the codon 352 of the mature protein in both of the neonates. This mutation resulted in a frameshift and a premature stop codon (TGA) 374. Their mothers were shown to be heterozygotes. We detected a single nucleotide deletion resulting in a frameshift in two male Korean neonates who had complete TBG deficiency.

• Applied Biological Chemistry
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• v.48 no.4
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• pp.364-369
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• 2005

This study was performed to elucidate substrate specificity to the locust bean gum galactomannan by Trichoderma harzianum ${\beta}-mannanase$. The medium composition for enzyme production were determined 3% cellulose, 3% corn steep liquor, 1% $KH_2PO_4$, 0.2% $(NH_4){_2}SO_4$, and incubated for 115 hr at $28^{\circ}C$. The ${\beta}-mannanase$ exhibited maximum activity at pH 4.5 and $60^{\circ}C$. Locust bean gum galactomannan was hydrolyzed by the ${\beta}-mannanase$, and then hydrolysates separated by activated carbon column chromatography. The main hydrolysates were composed of D.P 4 and 7 galactosyl mannooligosaccharides by TLC. For the elucidate the structure of D.P 4 and 7 oligosaccharides, methylation analysis was performed. D.P 4 and 7 were identified as M-M-M-M and M-M-M-M-M (G- and M-represent ${\alpha-1,6-D-galactosidic\;and\;{\beta}-1,4-mannosidic$ linkages, respectively). //G-G To investigate the effects of locust bean gum galactosyl mannooligosaccharides on the in vitro growth of B. longum, B. bifidum, B. infantis, and B. breve, Bifidobacterium spp. were cultivated individually on the modified-MRS medium containing carbon source such as D.P 4 and 7 galactosyl mannooligosaccharides, respectively. B. longum grew up 3.4-fold and 4.3-fold more effectively by the replacement of D.P 4 and 7 galactosyl mannooligosaccharides as the carbon source in a comparasion of standard MRS.