• Korean Journal of Veterinary Research
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• v.36 no.3
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• pp.699-707
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• 1996

This study was designed to examine the involvement of lead in function of target organ, and the protective effect of selenium in lead-treated guinea pigs for 8 weeks. The effects of exposure to 0.5% lead acetate(lead) and/or 4ppm sodium selenite(selenium) in feed on serveral aspects were evaluated by measuring thyroid stimulating hormone(TSH), triiodothyronine($T_3$), thyroxine($T_4$), serum biochemical activities, organ weights, and serum and organ lead concentrations in growing animals. The many indicators of endocrine function(TSH, $T_3$, and $T_4$ in serum), enzyme and biochemical activities(${\alpha}$-glutamyltranspeptidase, alkaline phosphatase, lactate dehydrogenase, triglyceride, creatinine, $Ca^{2+}$ in serum), and organ weights(kidney, spleen and testis) were correlated with lead exposure or showed significantly different mean values between the exposed and controls. These changes on some aspects were reversed by combination-fed of selenium, but did not statistically significant. The organ(kidney, liver, spleen, testis and brain) and serum lead concentrations of lead-fed group were clearly higher than that of controls. Selenium supplementation resulted in a significant protection against lead accumulation in liver and testis. These results suggest that lead can cause a toxic effect on several organ and that selenium seems to has a protective effect on specific reaction by lead-induced organic function toxicity.

• Molecules and Cells
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• v.39 no.10
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• pp.768-775
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• 2016

The Arabidopsis female gametophyte contains seven cells with eight haploid nuclei buried within layers of sporophytic tissue. Following double fertilization, the egg and central cells of the gametophyte develop into the embryo and endosperm of the seed, respectively. The epigenetic status of the central cell has long presented an enigma due both to its inaccessibility, and the fascinating epigenome of the endosperm, thought to have been inherited from the central cell following activity of the DEMETER demethylase enzyme, prior to fertilization. Here, we present for the first time, a method to isolate pure populations of Arabidopsis central cell nuclei. Utilizing a protocol designed to isolate leaf mesophyll protoplasts, we systematically optimized each step in order to efficiently separate central cells from the female gametophyte. We use initial manual pistil dissection followed by the derivation of central cell protoplasts, during which process the central cell emerges from the micropylar pole of the embryo sac. Then, we use a modified version of the Isolation of Nuclei TAgged in specific Cell Types (INTACT) protocol to purify central cell nuclei, resulting in a purity of 75-90% and a yield sufficient to undertake downstream molecular analyses. We find that the process is highly dependent on the health of the original plant tissue used, and the efficiency of protoplasting solution infiltration into the gametophyte. By isolating pure central cell populations, we have enabled elucidation of the physiology of this rare cell type, which in the future will provide novel insights into Arabidopsis reproduction.

• YAKHAK HOEJI
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• v.45 no.2
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• pp.180-189
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• 2001

We have reported that water-extracted Korean mistletoe (KM-110) had various biological activities such as antitumor and immunomodulatory activity, and the pectin fraction (KML-C) of the extract was one of major factors related to its biological functions. In this paper, we produced murine monoclonal antibody (mAb) against KML-C. The cAbs obtained were largely classified into two groups according to specificity to KML-C and ML-I, a pectin from European mistletoe. One group mAbs (9H7-D10 and 3C2-lH4) strongly reacted with KML-C, but not ML-I. In contrast, another group cAbs (8Bll-2C5, BE12-3E9 and 5E10-Fl) reacted with both KML-C and ML-1. The subisotypes of these mobs were shown to be IgGl (9H7-lD10, 3C2-lH4 and 8Bll-2C5) or IgM (8E12-3E9 and 5E10-Fl). To develop an assay system for determination of the amount of KML-C, we established the sandwich ELISA (enzyme-linked immunosorbent assay) method using these mAbs and horse radish peroxidase (HRP)-labelled cAbs. In various combinations of the cAbs for coated antibody and detection antibody, the sandwich ELISA quantitatively detected KML-C, showing the detection limit ranging from 7-5,000 ng/ml. Especially reproducibility (C.V) of the sandwich ELISA, in which 8E12-3E9 was used for coating antibody and 8Bll-2C5-HRP for detection antibody, was 4.59-5.83 in intra assay, and 3.9-9.4 in inter assay.

• Korean Journal of Veterinary Research
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• v.46 no.1
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• pp.35-41
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• 2006

Vitellogenin (Vtg), a phospholipoglycoprotein precursor of egg yolk is synthesized and secreted from the liver in response to estrogens in female fish. Vtg is normally undetectable in the blood of male fish, but can be induced by exposure to chemicals possessing estrogenic activity. Thus, the presence of Vtg in blood of male fish can serve as a useful biomarker for assessing previous exposure to estrogenic compounds. In the present study, Vtg was abnormally expressed in Rhynchocypris oxycephalus using estradiol benzoate ($E_2$). As the result, it was found that the level of Vtg in blood from R. oxycephalus was increased by treated quantity of $E_2$ with dose-effect manner. Monoclonal antibodies were generated against Vtg of R. oxycephalus. The hybridoma were screened with an enzyme immunoassay for the production of specific anti-Vtg antibodies. Five positive cell lines with a high specificity were selected. Monoclonal antibodies against vtg of R. oxycephalus that was developed in this study, may be a useful bio-indicator for the detection of estrogenic contamination in the aquatic ecosystem.

• Journal of Ginseng Research
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• v.36 no.4
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• pp.449-460
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• 2012

Plants have versatile detoxification systems to encounter the phytotoxicity of the wide range of natural and synthetic compounds present in the environment. Glutathione S-transferase (GST) is an enzyme that detoxifies natural and exogenous toxic compounds by conjugation with glutathione (GSH). Recently, several roles of GST giving stress tolerance in plants have demonstrated, but little is known about the role of ginseng GSTs. Therefore, this work aimed to provide further information on the GST gene present in Panax ginseng genome as well as its expression and function. A GST cDNA (PgGST) was isolated from P. ginseng cDNA library, and it showed the amino acid sequence similarity with theta type of GSTs. PgGST in ginseng plant was induced by exposure to metals, plant hormone, heavy metals, and high light irradiance. To improve the resistance against environmental stresses, full-length cDNA of PgGST was introduced into Nicotiana tabacum. Overexpression of PgGST led to twofold increase in GST-specific activity compared to the non-transgenic plants, and the GST overexpressed plant showed resistance against herbicide phosphinothricin. The results suggested that the PgGST isolated from ginseng might have a role in the protection mechanism against toxic materials such as heavy metals and herbicides.

• Molecules and Cells
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• v.43 no.3
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• pp.286-297
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• 2020

Mammalian patatin-like phospholipase domain containing proteins (PNPLAs) play critical roles in triglyceride hydrolysis, phospholipids metabolism, and lipid droplet (LD) homeostasis. PNPLA7 is a lysophosphatidylcholine hydrolase anchored on the endoplasmic reticulum which associates with LDs through its catalytic region (PNPLA7-C) in response to increased cyclic nucleotide levels. However, the interaction of PNPLA7 with LDs through its catalytic region is unknown. Herein, we demonstrate that PNPLA7-C localizes to the mature LDs ex vivo and also colocalizes with pre-existing LDs. Localization of PNPLA7-C with LDs induces LDs clustering via non-enzymatic intermolecular associations, while PNPLA7 alone does not induce LD clustering. Residues 742-1016 contains four putative transmembrane domains which act as a LD targeting motif and are required for the localization of PNPLA7-C to LDs. Furthermore, the N-terminal flanking region of the LD targeting motif, residues 681-741, contributes to the LD targeting, whereas the C-terminal flanking region (1169-1326) has an anti-LD targeting effect. Interestingly, the LD targeting motif does not exhibit lysophosphatidylcholine hydrolase activity even though it associates with LDs phospholipid membranes. These findings characterize the specific functional domains of PNPLA7 mediating subcellular positioning and interactions with LDs, as wells as providing critical insights into the structure of this evolutionarily conserved phospholipid-metabolizing enzyme family.

• KSBB Journal
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• v.10 no.3
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• pp.271-282
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• 1995

The authentic hGH converted from met-hGH by immobilized ApM was purified by successive chromatographic processes based on the differences in isoelectric points, hydrophobicities and charges. The final recovery yield was about 14.1% and the specific activity of the purified hGH was 2.75IU per mg when assayed by enzyme immunoassay. The purified hGH was verified to be authentic hGH through the analysis of amino acid composition, amino-terminal amino acid sequence, carboxy-terminal amino acid and tryptic peptide map. The purity of purified hGH was higher than that of commercial hGH when assessed by SDS-PAGE, PAGE, IEF and HSGF. In weight-gain assay and tibia test with hypophysectomized rats, the hGH produced in this study showed the same growth effect as the commercial hGH.

• Journal of Microbiology and Biotechnology
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• v.25 no.8
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• pp.1281-1290
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• 2015

Thermolysin and its homologs are a group of metalloproteases that have been widely used in both therapeutic and biotechnological applications. We here report the identification and characterization of a novel thermolysin-like protease, BtsTLP1, from insect pathogen Bacillus thuringiensis serovar Sichuansis strain MC28. BtsTLP1 is extracellularly produced in Bacillus subtilis, and the active protein was purified via successive chromatographic steps. The mature form of BtsTLP1 has a molecule mass of 35.6 kDa as determined by mass spectrometry analyses. The biochemical characterization indicates that BtsTLP1 has an apparent K_m value of 1.57 mg/ml for azocasein and is active between 20℃ and 80℃. Unlike other reported neutral gram-positive thermolysin homologs with optimal pH around 7, BtsTLP1 exhibits an alkaline pH optimum around 10. The activity of BtsTLP1 is strongly inhibited by EDTA and a group of specific divalent ions, with Zn²⁺ and Cu²⁺ showing particular effects in promoting the enzyme autolysis. Furthermore, our data also indicate that BtsTLP1 has potential in cleaning applications.

• Journal of Microbiology and Biotechnology
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• v.22 no.7
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• pp.947-959
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• 2012

This study was aimed at an evaluation of the potential inheritance of electroporation effects on Lactobacillus fermentum BT 8219 through to three subsequent subcultures, based on their growth, isoflavone bioconversion activities, and probiotic properties, in biotin-supplemented soymilk. Electroporation was seen to cause cell death immediately after treatment, followed by higher growth than the control during fermentation in biotin-soymilk (P<0.05). This was associated with enhanced intracellular and extracellular ${\beta}$-glucosidase specific activity, leading to increased bioconversion of isoflavone glucosides to aglycones (P<0.05). The growing characteristics, enzyme, and isoflavone bioconversion activities of the first, second, and third subcultures of treated cells in biotin-soymilk were similar to the control (P>0.05). Electroporation affected the probiotic properties of parent L. fermentum BT 8219, by reducing its tolerance towards acid (pH 2) and bile, lowering its inhibitory activities against selected pathogens, and reducing its ability for adhesion, when compared with the control (P<0.05). The first, second, and third subcultures of the treated cells showed comparable traits with that of the control (P>0.05), with the exception of their bile tolerance ability, which was inherited to the treated cells of the first and second subcultures (P<0.05). Our results suggest that electroporation could be used to increase the bioactivity of biotin-soymilk via fermentation with probiotic L. fermentum BT 8219, with a view towards the development of functional foods.

• Mycobiology
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• v.44 no.4
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• pp.260-268
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• 2016

Regulation of alkaline-resistant laccase from Perenniporia tephropora KU-Alk4 was proved to be controlled by several factors. One important factor was the initial pH, which drove the fungus to produce different kinds of ligninolytic enzymes. P. tephropora KU-Alk4 could grow at pH 4.5, 7.0, and 8.0. The fungus produced laccase and MnP at pH 7.0, but only laccase at pH 8.0. The specific activity of laccase in the pH 8.0 culture was higher than that in the pH 7.0 culture. At pH 8.0, glucose was the best carbon source for laccase production but growth was better with lactose. Low concentrations of glucose at 0.1% to 1.0% enhanced laccase production, while concentrations over 1% gave contradictory results. Veratryl alcohol induced the production of laccase. A trace concentration of copper ions was required for laccase production. Biomass increased with an increasing rate of aeration of shaking flasks from 100 to 140 rpm; however, shaking at over 120 rpm decreased laccase quantity. Highest amount of laccase produced by KU-Alk4, 360 U/mL, was at pH 8.0 with 1% glucose and 0.2 mM copper sulfate, unshaken for the first 3 days, followed by addition of 0.85 mM veratryl alcohol and shaking at 120 rpm. The crude enzyme was significantly stable in alkaline pH 8.0~10.0 for 24 hr. After treating the pulp mill effluent with the KU-Alk4 system for 3 days, pH decreased from 9.6 to 6.8, with reduction of color and chemical oxygen demand at 83.2% and 81%, respectively. Laccase was detectable during the biotreatment process.