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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of Life Science
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Korean Society of Life Science
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Volume & Issues
Volume 23, Issue 12 - Dec 2013
Volume 23, Issue 11 - Nov 2013
Volume 23, Issue 10 - Oct 2013
Volume 23, Issue 9 - Sep 2013
Volume 23, Issue 8 - Aug 2013
Volume 23, Issue 7 - Jul 2013
Volume 23, Issue 6 - Jun 2013
Volume 23, Issue 5 - May 2013
Volume 23, Issue 4 - Apr 2013
Volume 23, Issue 3 - Mar 2013
Volume 23, Issue 2 - Feb 2013
Volume 23, Issue 1 - Jan 2013
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Contribution of Nociceptin to Alterations in Cerebral Blood Flow Regulation Following Postnatal Exposure to Ethanol in Rats
Cho, Dong Hwan ; Lee, Won Suk ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 157~166
DOI : 10.5352/JLS.2013.23.2.157
This study aimed to investigate whether nociceptin contributes to the alterations in cerebral blood flow (CBF) regulation following postnatal exposure to ethanol in Sprague-Dawley rats. Animals received ethanol twice a day, 2 hr apart, on postnatal 6, 7 and 8 days. The changes in regional CBF (rCBF) in response to the changes in mean arterial blood pressure were determined at 4-, 8-, and 12-week of age by laser-Doppler flowmetry. Hypotension was induced by the gradual withdrawal of blood from arterial catheter, and the reversal of blood pressure was produced by the reinfusion of blood. Expression of nociceptin-like immunoreactivity was determined in dura mater and cerebral cortex using immunohistochemistry. Postnatal exposure to ethanol almost abolished the autoregulation of rCBF in all age groups. Pretreatment with nociceptin but not with [
, a selective competitive nociceptin receptor antagonist, 5 min prior to ethanol administration preserved the autoregulation of rCBF in all age groups. Postnatal exposure to ethanol markedly increased the expressions of nociceptin-like immunoreactivity in the dura mater and cerebral cortex, both of which were significantly inhibited by pretreatment with 7-nitroindazole monosodium salt as well as aminoguanidine 5 min prior to ethanol administration in all age groups. The values of arterial blood gas analysis were not significantly different from the basal levels in all groups. These results suggest that nociceptin deeply contributes to the compensatory mechanisms for the nitric oxide-dependent alterations in CBF autoregulation following postnatal exposure to ethanol.
Construction and In vitro Study of a Prx 6/Luc Vector System for Screening Antioxidant Compounds in the Transgenic Mice
Lee, Young Ju ; Nam, So Hee ; Kim, Ji Eun ; Hwang, In Sik ; Lee, Hye Ryun ; Choi, Sun Il ; Kwak, Moon Hwa ; Lee, Jae Ho ; Jung, Young Jin ; An, Beum Soo ; Hwang, Dae Youn ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 167~174
DOI : 10.5352/JLS.2013.23.2.167
Peroxiredoxin 6 (Prx 6) is a member of the thiol-specific antioxidant protein family, which may play a role in protection against oxidative stress and in regulating phospholipid turnover. The aim of this study was to determine whether a human Prx 6/Luc vector was stably expressed and responded to antioxidants in a lung cell line (NCI-H460). To achieve this, the luciferase signal, hPrx 6 mRNA expression, and superoxide dismutase (SOD) activity were measured in transfectants with a hPrx 6/Luc plasmid after treatment with four antioxidant extracts, including Korea white ginseng (KWG), Korea red ginseng (KRG), Liriope platyphylla (LP), and red Liriope platyphylla (RLP). First, the hPrx 6/Luc plasmid was successfully constructed with DNA fragments of human Prx 6 promoter, amplified by PCR using genomic DNA isolated from NCI-H460 cells, and cloned into the pTransLucent reporter vector. The orientation and sequencing of the hPrx 6/Luc plasmid were identified with restriction enzyme and automatic sequencing. A luciferase assay revealed significant enhancement of luciferase activity in the four treatment groups compared with a vehicle-treated group, although the ratio of the increase was different within each group. The KRG- and LP-treated groups showed higher activity than the KWG- and RLP-treated groups. Furthermore, the luciferase activity against RLP occurred roughly in a dose-dependent manner. However, the level of endogenous hPrx 6 mRNA did not change in any group treated with the four extracts. The SOD activity was in agreement with the luciferase activity. Therefore, these results indicate that the hPrx 6/Luc vector system may successfully express and respond to antioxidant compounds in NCI-H460 cells. The data also suggest that the Prx 6/Luc vector system may be effectively applied in screening the response of hPrx 6 to antioxidant compounds in transgenic mice.
Characterization of Acute Hepatitis Virus A Genotype in Korea
Kim, Mi Hyun ; Choi, Hayana ; Pak, Kun Sik ; Seong, Chi Nam ; Cho, Hyun Wook ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 175~181
DOI : 10.5352/JLS.2013.23.2.175
In Korea, most hepatitis A virus is the IA genotype, but reports of other genotypes have increased recently. Therefore, the purpose of this study is to conduct a genotypic analysis of acute hepatitis A virus. From April 2010 to April 2011, clinical specimens from 20 patients hospitalized with acute hepatitis A and 36 sera positive for anti-HAV IgM were obtained, and the genotype of the VP1/P2A region was analyzed. RNA sequences of the VP1/P2A junction region were amplified using RT-PCR, and the sequences were compared. From 50 sequences amplified, 4 sequences (8%) belonged to genotype IA. The remaining 46 (92%) belonged to genotype IIIA. The results indicate that the genotype of the hepatitis A virus has changed from IA to IIIA in Korea.
Isolation and Characterization of Expansin Genes in a Halophyte, Suaeda japonica
Hwang, Soong-Taek ; Kim, Suk Kyu ; Na, Jong Gil ; Lee, Jeom Sook ; Choi, Dongsu ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 182~189
DOI : 10.5352/JLS.2013.23.2.182
Halophytes are unique land plants that are capable of thriving in a high-salt environment. They are attracting public attention due to their ability to synthesize bioactive substances such as UV protectants or antioxidizing agents. To achieve unaffected growth under high salinity, halophytes may take advantage of the activities of cell growth factors such as expansins. Expansins are well-known cell wall proteins that are responsible for cell enlargement. They loosen cell walls, thereby contributing to actual plant growth. This study aimed to identify positive roles of expansins in the growth of halophytes. Three expansin cDNA clones were isolated from seedlings of Suaeda japonica. Comparing the deduced amino acid sequences of the expansin genes of S. japonica with those of other plant species suggested that the cDNA clones isolated from S. japonica belong to the EXPA (
-expansin) gene family. A phylogenetic tree based on the deduced amino acid sequences revealed that the expansins of S. japonica share a close evolutionary relationship with those of strawberry (Fragaria ananassa) and jujube (Ziziphus jujuba), both of which are woody dicots. SjEXPAs did not show any remarkable change in the gene expression level in different NaCl concentrations, providing a clue to the unaffected seedling growth of S. japonica in a high-salt environment. In conclusion, the present study presents the first report of expansin genes from halophytes and suggests a putative role for these genes in plant growth under high salinity.
Gene Promoter Variation of Phosphoglycerate Kinase, a Glucose Metabolism Enzyme, is a Biomarker for Selection of Disease-resistant Sea Squirt, Halocynthia Roretzi
Cho, Hyun Kook ; Hur, Young Baek ; Cheong, Jae Hun ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 190~196
DOI : 10.5352/JLS.2013.23.2.190
The sea squirt, Halocynthia roretzi, has experienced mass mortality due to softness syndrome. The identification of disease-induced genes can provide insights into the development of this syndrome. To identify the genes, we performed differentially expressed gene (DEG) analysis. The expression of the phosphoglycerate kinase (HrPGK) gene was significantly decreased in diseased sea squirts compared to normal ones. We confirmed the result of the DEG analysis through RT-PCR and real-time PCR. In addition, we detected single nucleotide polymorphisms at position -106 (A/T) and -254 (G/T) in the HrPGK gene promoter by genotyping analysis. At the -106 site of the HrPGK gene, the frequency of the AA allele in disease-resistant sea squirts was about two-fold higher than that of sensitive ones, and the frequency of the TT allele in the disease-resistant sea squirts was about six-fold lower. At the -254 site of the HrPGK gene, the frequency of the GT and the GG allele was approximately two-fold higher and two-fold lower, respectively, in the disease-resistant sea squirts compared to the disease-sensitive ones. Analysis of the relationship between the genotypic variation at the -106/-254 promoter and the expression of HrPGK mRNA showed that HrPGK mRNA expression was higher in the -106/-254 AA/GT genotype samples than in the -106/254 TT/GG genotype ones. These results show that sea squirts harboring the AA/GT genotype may have more resistance to mortality than the sea squirts with other genotypes.
Presence of Leukemia-maintaining Cells in Differentiation-resistant Fraction of K562 Chronic Myelogenous Leukemia
Lee, Hong-Rae ; Kim, Mi-Ju ; Ha, Gahee ; Kim, So-Jung ; Kim, Sun-Hee ; Kang, Chi-Dug ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 197~206
DOI : 10.5352/JLS.2013.23.2.197
The present study investigated whether leukemia-maintaining cells reside in a differentiation-resistant fraction using a megakaryocytic differentiation model of K562 cells. Treatment with phorbol-12-myristate-13-acetate (PMA) significantly inhibited the colony-forming efficiency of the K562 cells. At a PMA concentration of 1 nM or higher, colony was not formed, but approximately 40% of K562 cells still survived in soft agar. Approximately 70% of colony-forming cells that were isolated following the removal of PMA after exposure to the agent were differentiated after treatment with 10 nM PMA for 3 days. The differentiation rate of the colony-forming cells was gradually increased and reached about 90% 6 weeks after colony isolation, which was comparable to the level of a PMA-treated K562 control. Meanwhile, imatinib-resistant variants from the K562 cells, including K562/R1, K562/R2, and K562/R3 cells, did not show any colony-forming activity, and most imatinib-resistant variants were CD44 positive. After 4 months of culture in drug-free medium, the surface level of CD44 was decreased in comparison with primary imatinib-resistant variants, and a few colonies were formed from K562/R3 cells. In these cells, Bcr-Abl, which was lost in the imatinib-resistant variants, was re-expressed, and the original phenotypes of the K562 cells were partially recovered. These results suggest that leukemia-maintaining cells might reside in a differentiation-resistant population. Differentiation therapy to eliminate leukemia-maintaining cells could be a successful treatment for leukemia if the leukemia-maintaining cells were exposed to a differentiation inducer for a long time and at a high dose.
Resveratrol Up-regulates Cysteine-rich Angiogenic Inducer 61 (CYR61) in Human Colorectal Cancer Cells
Kwak, Eun-Hee ; Kim, Jong-Sik ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 207~212
DOI : 10.5352/JLS.2013.23.2.207
In this paper, we investigated whether resveratrol could induce the expression of cysteine-rich angiogenic inducer 61 (CYR61), which is a member of the CCN families. We showed that resveratrol up-regulated CYR61 protein expression in three different human colorectal cancer cell lines. In addition, resveratrol induced CYR61 protein expression in a dose- and time-dependent manner in a HCT116 cell line. To investigate the relationship between various biological activities of resveratrol and CYR61 expression, HCT116 cells were incubated with several NSAIDs, antioxidants, or resveratrol. Interestingly, resveratrol only induced CYR61 protein expression. The expression of CYR61 was not related to the presence of p53. A promoter assay revealed that the 786-bp promoter region (-732/+54) contains a regulatory region and that indole-3-carbinol and 6-gingerol could not induce CYR61 expression. In conclusion, our results indicate up-regulation of CYR61 is extremely resveratrol specific. The results can help to shed light on the unique biological function of resveratrol.
Anti-inflammatory Effect and Antioxidative Activities of Ingredients used in Bibimbab
Ko, Yu-Jin ; Seol, Hui-Gyeong ; Lee, Gyeong-Ran ; Jeong, Gye-Im ; Ryu, Chung-Ho ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 213~221
DOI : 10.5352/JLS.2013.23.2.213
Bibimbab (mixed rice) is a traditional Korean one-dish meal. This study was carried out to investigate the anti-inflammatory and antioxidative effects of raw and seasoned ingredients used in Bibimbab (Cucurbita moschata P., Platycodon grandiflorum A., Vigna radiata L., Porphyra yezonensis udea, Allium ampeloprasum L., Pterdium aguilinum, Raphanus sativus). Human mast cells (HMC-1) were pretreated with 70% ethanol extracts of Bibimbab and further cultured for an appropriate time after the addition of phorbol 12-myristate 13-acetate (PMA) and calcium ionophore A23187. Cell viability was determined by an MTT assay. None of the ingredients showed cytotoxic effects at a concentration of 1.0
. Anti-inflammatory effects were analyzed at 0.01, 0.1, and 1.0 mg/ml concentrations of the raw, seasoned ingredients of PMA. A23187 stimulated HMC-1. Among the various ingredients, seasoned A. ampeloprasum L. extract showed the highest inhibition of TNF-
and IL-6 secretion (90% and 93%, respectively) at a concentration of 1.0 mg/ml. The R. sativus extract showed the highest inhibition (85%) of IL-8 secretion. DPPH analysis of the antioxidation properties of the ingredients showed that raw and seasoned A. ampeloprasum extracts exhibited the highest DPPH free radical scavenging activity (67.50 and 73.65%, respectively). These results suggest that seasoned ingredients used in Bibimbab have lower anti-inflammatory effects in relation to TNF-
and IL-6 secretion than raw ingredients in PMA- and A23187-treated HMC-1. In addition, the seasoned ingredients showed a tendency to increase antioxidative activity. Therefore, the ingredients used in Bibimbab have potential as anti-inflammatory and antioxidation agents.
Leavening Ability of the Isolate Saccharomyces cerevisiae MF10003 in Bakery Dough
Oh, Jung-Suk ; Min, Eung-Ki ; Ahn, Chang-Hyun ; Han, Yeong-Hwan ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 222~227
DOI : 10.5352/JLS.2013.23.2.222
An effective leavening yeast was isolated from raisin broth. The isolate was identified as Saccharomyces cerevisiae by comparing the homology of 18S rDNA ITS sequences and named as S. cerevisiae MF10003. S. cerevisiae MF10003 showed a 1.9-fold and 3.1-fold increase in
production and leavening ability, respectively, compared with the wild yeast S. ellipsoideus KCTC7243, and the dough had a rich and volatile flavor. When glucose, sucrose, fructose, and maltose were added to the culture broth as a carbon and energy source,
was produced in 4 hr.
Effects of Medicinal Enzyme Powder on Intestinal Mobility, Lipid Level, and Blood Parameters of Loperamide-Induced Constipation in Rats
Park, Chan Sung ; Park, Kyung Soo ; Kim, Mi Lim ; Kong, Hyun Joo ; Yang, Kyung Mi ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 228~236
DOI : 10.5352/JLS.2013.23.2.228
This study was aimed at investigating whether dietary therapy using medicinal enzyme powder is effective in reducing constipation caused by loperamide in rats. Nine-week-old male Sprague Dawley were subdivided into 4 groups: normal diet group (C), loperamide treatment and normal diet (CL), medicinal enzyme powder diet (E), and loperamide treatment and medicinal enzyme powder diet (EL). Constipation was induced by subcutaneous injection of loperamide (1.5 mg/kg) 3 days prior to sacrifice. The treatment with loperamide led to an increase in weight gain, a decrease in the number and wet weight of fecal pellets, and a decrease in intestinal motility. The administration of the medicinal enzyme powder significantly reduced weight gain but increased intestinal mobility compared with the loperamide-treated group. The treatment with loperamide in the normal diet group reduced the activities of both suggesting that constipation may be involved in the low level of glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT). Additionally, the loperamide treatment in the medicinal enzyme powder diet group increased the level of GOT, but reduced the level of GPT. Loperamide treatment also reduced cholesterol and increased the atherogenic index (AI) and cardiac risk factors (CRFs). Interestingly, the treatment with the medicinal enzyme powder effectively attenuated both the increase in AI and the reduction in high density lipopretein (HDL)-cholesterol, caused by the treatment with loperamide. Although there were no significant differences in the blood protein level, including hemoglobin and hematocrit, between the normal diet group and the loperamide-treated group, the administration of the medicinal enzyme powder to the loperamide-treated group effectively increased the levels of both hemoglobin and hematocrit. Collectively, the results demonstrate that the medicinal enzyme powder can help to combat the negative events caused by constipation.
Effect of Barley Containing Different Levels of Anthocyanin on the Performance and Egg Quality of Laying Hens
Choe, Ho Seong ; Song, Tae Hwa ; Han, Ouk Kyu ; Park, Tae Il ; Ryu, Kyeong Seon ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 237~241
DOI : 10.5352/JLS.2013.23.2.237
To evaluate the effects of anthocyanin-fortified barley (AFB) and whole crop barley (WCB) addition to diets, 200 Brown Nick hens were assigned to 5 treatments with 5 replicates for 8 weeks. All the treated groups differed in feed intake, egg production, egg weight, and egg mass compared to those of a control group. As the intake of barley was increased, feed intake, egg production, and egg mass decreased. In terms of egg quality, the yolk color (YC), the egg shell breaking strength (SBS), and the egg shell color (SC) differed up to 6 weeks of growth. Feeding the WCB and AFB to laying hens up to 8 weeks had a positive influence on albumin height (AH) and the haugh unit (HU). Up to 6 weeks of growth, increasing the amount of barley in the diets of the laying hens had a positive effect on the SC and the YC but had no effect on the SBS. Diets including 20% AFB and WCB increased the AH and HU to 9.10 and 94.53, respectively. The results suggest that the addition of AFB and WCB up to 10% to the diets of laying hens could improve the laying performance and the egg quality.
Isolation and Characterization of a Novel Bacterium, Bacillus subtilis HR-1019, with Insoluble Phosphates Solubilizing Activity
Lee, Yong-Suk ; Park, Dong-Ju ; Kim, Jae Hoon ; Kim, Hyeong Seok ; Choi, Yong-Lark ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 242~248
DOI : 10.5352/JLS.2013.23.2.242
The objective of this study was to develop a mineral phosphate-solubilizing bacterium as a biofertilizer. A mineral phosphate-solubilizing bacterium HR-1019 was isolated from cultivated soils. It was identified as Bacillus subtilis by 16S rDNA analysis. The phosphate-solubilizing activities of the HR-1019 strain against three types of insoluble phosphate, hydroxyapatite, tri-calcium phosphate, and aluminum phosphate were quantitatively determined. When 5% of glucose concentration was used as a carbon source, the strain showed marked mineral phosphate-solubilizing activity. Mineral phosphate solubilization was directly related to pH drop in the culture solution of the strain. The pathogenic activity and antifungal effects of the HR-1019 strain were measured inclear zones formed in PDA media.
Antioxidative Activity and Chemical Characteristics of Cordycepin-enriched Cordyceps militaris JLM0636 Powder
Ahn, Hee-Young ; Cha, Jae-Young ; Jeong, Yong-Kee ; Cho, Young-Su ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 249~258
DOI : 10.5352/JLS.2013.23.2.249
The antioxidative activity and bioactivity of water, ethanol, and methanol extracts from Paecilomyces japonica (PJ), Cordyceps militaris (CM), and cordycepin-enriched C. militaris JLM0636 (
) were tested in in vitro experimental models. The PJ water extract showed the highest extraction yield (42.53%). The highest content of phenolic compounds and flavonoids were found in the water extract of PJ, 2.72% and 1.73%, respectively. The major minerals were K, Mg, and Ca. The water extracts of PJ also showed the highest DPPH free radical scavenging activity and reducing power. Linoleic acid peroxidation and antioxidative activities were strong in
. The methanol extracts of PJ showed the highest inhibition activity against tyrosinase. Fibriolytic activity was higher in
than in CM. These results may provide basic data to understand the biological activities of bioactive materials derived from
for the development of functional foods, cosmetics, and antithrombotics.
Isolation of Bacteria with Protease Activity from Cheonggukjang and Purification of Fibrinolytic Enzyme
Choi, Yeon Hee ; Lee, Jun Seung ; Bae, So Young ; Yang, Keun Jae ; Yeom, Kyu Won ; Jo, Dong Hyeok ; Kang, Ock Hwa ; Baik, Hyung Suk ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 259~266
DOI : 10.5352/JLS.2013.23.2.259
To isolate the fibrinolytic enzyme, 268 strains from 21 samples were morphologically isolated from Cheonggukjang collected from Korea and Japan. Among the 268 strains, protease-producing bacteria were isolated in nutrient agar medium including 1% skimmed milk. As a result of this, 22 strains were isolated. Apiweb site was used to identify these strains based on their biochemical properties. In addition, 16S rRNA sequencing was performed to identify the strain. Most of the identified strains were Bacillus subtilis and B. amyloliquefaciens. Fibrinolytic enzyme activity was measured with the fibrin plate method. Five strains were finally selected: A2-14, A2-20, C1-05, C1-09, and F2-01. Of those five strains, the A2-20 strain, which is close to B. amyloliquefaciens, showed the strongest fibrinolytic activity. The fibrinolytic enzyme produced by the A2-20 strain was partially purified from culture supernatant by gel filtration and ion exchange chromatography. The optimal pH and temperature values of the partially purified enzyme were 7.0 and
, respectively. Purified protein analysis was carried out with SDS-PAGE and zymography. A genetic analysis was also conducted by PCR based on the consensus sequence of fibrinolytic enzyme. Corresponding genes with a partial sequence of the A2-20 strain were identified.
Micrografting and Heat Treatment Combination for Eliminating Virus of CTV-infected Citrus
Chae, Chi Won ; Yun, Su Hyun ; Park, Jae Ho ; Hyun, Jae Wook ; Koh, Sang Wook ; Lee, Dong Hoon ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 267~272
DOI : 10.5352/JLS.2013.23.2.267
This study was conducted to eliminate viruses from citrus-infected plants using micrografting and thermotherapy. Six citrus cultivars including a 'Setoka' hybrid were used as plant sources. The TAS-ELISA technique demonstrated that several plants were CTV positive. However, no CTV symptoms were detected in plants obtained from shoots and treated at a high temperature of
during the day and night and micrografted for two weeks with old trifoliate orange rootstock in vitro. Indexing of CTV, SDV, and CTLV for RT-PCR analysis of the eleven citrus seedlings, including 'Setoka', 'Samdajosang', 'Pungkwang', 'Shiranuhi', and 'Ehimekashi dai28go' was virus free following the micrografting and thermal therapy.
Production and Characterization of Alkaline Protease of Micrococcus sp. PS-1 Isolated from Seawater
Jin, Young-Rang ; Yu, Sun-Nyoung ; Kim, Kwang-Youn ; Kim, Sang-Hun ; Park, Seul-Ki ; Kim, Hyeun-Kyeung ; Lee, Yong-Seok ; Choi, Yong-Lark ; Ji, Jae Hoon ; Ahn, Soon-Cheol ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 273~281
DOI : 10.5352/JLS.2013.23.2.273
The purpose of this research was to investigate the production and characterization of alkaline protease from Micrococcus sp. PS-1 newly isolated from seawater. Micrococcus sp. PS-1 was grown in Luria-Bertani (LB) medium. Its optimal temperature and pH for growth were
and 7.0, respectively. The effect of nitrogen sources was investigated on optimal enzyme production. A high level of alkaline protease production occurred in LB broth containing 2% skimmed milk. The protease was purified in a 3-step procedure involving ultrafiltration, acetone precipitation, and dialysis. The procedure yielded a 16.43-purification fold, with a yield of 54.25%. SDS-PAGE showed that the enzyme had molecular weights of 35.0 and 37.5 kDa. Its maximum protease activity was exhibited at pH 9.0 and
, and its activity was stable at pH 8.0-11.0 and
. The protease activity was strongly inhibited by PMSF, EDTA, and EGTA. Taken together, the results demonstrate that the protease enzyme from Micrococcus sp. PS-1 probably belongs to a subclass of alkaline metallo-serine proteases.
Effects of Makgeolli and Makgeolli precipitate on Hepatotoxicity and Serum Lipid Content in Rats
Kim, Bo Kyung ; Kang, Min Sook ; Jeon, Myeong-Jeong ; Lee, Sang-Hyeon ; Kim, Mihyang ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 282~289
DOI : 10.5352/JLS.2013.23.2.282
This study was conducted to investigate the effect of Makgeolli and Makgeolli precipitate on hepatotoxity and the serum lipid content in rats. First, we investigated the effect of Makgeolli and ethanol on the progress of alcoholic fatty liver. The effect of Makgeolli precipitate on carbon tetrachloride (
)-induced hepatotoxicity in the rats was then studied. Indicators of the health status of the experimental period, the body weight gain in ethanol-treated group tended to be lower than those in the control and the Makgeolli-treated groups. The weight of the liver tissue decreased significantly following the administration of ethanol. However, this was not seen following the administration of Makgeolli. The activities of serum aspartate transaminase (AST) and alanine transaminase (ALT) were decreased in the Makgeolli group compared to the ethanol group. Serum cholesterol concentrations increased in the ethanol group, but decreased in the Makgeolli-treated group to an equal volume of the ethanol-treated group. The serum HDL-cholesterol content was significantly higher in the Makgeolli group than in the ethanol group. Analysis of the impact of the Makgeolli precipitate on toxicity induced by
in the liver showed that the
treatment significantly increased the activities of serum ALT and AST. However, the levels of cholesterol and triglyceride in serum were decreased. The
treatment increased the activities of AST and ALT. However, the raw Makgeolli precipitate decreased their activities. Moreover, raw Makgeolli precipitate significantly reduced the
-induced elevation of serum lipids more than heated Makgeolli precipitate. These results suggest that raw Makgeolli precipitate may exert a protective effect against
-induced liver injury by preventing lipid peroxidation.
Development of New Vector Systems as Genetic Tools Applicable to Mycobacteria
Jeong, Ji-A ; Lee, Ha-Na ; Ko, In-Jeong ; Oh, Jeong-Il ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 290~298
DOI : 10.5352/JLS.2013.23.2.290
The genus Mycobacterium includes crucial animal and human pathogens such as Mycobacterium tuberculosis, Mycobacterium leprae, and Mycobacterium bovis. Although it is important to understand the genetic basis for their virulence and persistence in host, genetic analysis in mycobacteria was hampered by a lack of sufficient genetic tools. Therefore, many functional vectors as molecular genetic tools have been designed for understanding mycobacterial biology, and the application of these tools to mycobacteria has accelerated the study of mechanisms involved in virulence and gene expression. To overcome the pre-existing problems in genetic manipulation of mycobacteria, this paper reports new vector systems as effective genetic tools in Mycobacterium smegmatis. Three vectors were developed; pKOTs is a suicide vector for mutagenesis containing a temperature-sensitive replication origin (TSRO) and the sacB gene encoding levansucrase as a counterselectable marker. pMV306lacZ is an integrative lacZ transcriptional fusion vector that can be inserted into chromosomal DNA by site-specific recombination. pTnMod-OKmTs is a minitransposon vector harboring the TSRO that can be used in random mutagenesis. It was demonstrated in this study that these vectors effectively worked in M. smegmatis. The vector systems reported here are expected to successfully applicable to future research of mycobacterial molecular genetics.
Effect of Glucose on Swarming Motility of Paenibacillus sp. CK214
Kang, Sung Wan ; Yoo, Ah Young ; Kang, Ho Young ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 299~305
DOI : 10.5352/JLS.2013.23.2.299
Paenibacillus is a gram-positive, spore-forming aerobes that was previously classified as a Bacillus species. Paenibacillus sp. CK214 was highly motile on LB agar plates and showed typical colonial morphology of Paenibacillus. However, its motility was defective in the absence of glucose. Electron microscopic observation revealed that the cells of CK214 cultured on LB agar plates were peritrichously flagellated but not flagellated in the presence of glucose. Flagellar filaments were purified by centrifugation after shearing off from the CK214 cells with vigorous pipetting. The purified protein was composed of a single flagellin with an apparent molecular size of 29 kDa. Recognition of the protein by anti-Edwardsiella tarda flagellin protein antibody demonstrates that the protein is a flagellin protein. A decreased level of flagellin protein was detected in CK214 cells grown under glucose-supplemented media.
Application of Competitive ELISA Method for Estimation of Urinary Aflatoxin M1 Level
Kim, Yong-Dae ; Kim, Heon ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 306~310
DOI : 10.5352/JLS.2013.23.2.306
We compared the efficacy of the competitive ELISA method for measuring the level of urinary aflatoxin M1 (AFM1) with that of the HPLC-fluorescence detector (HPLC-FLD) method. The recovery rate of AFM1 with the ELISA method was 105% (73-124%), and the coefficient of variation of the analysis was 6.85%. The ELISA method showed a 0.20 pg/ml and 0.62 pg/ml limit of detection and limit of quantitation, respectively. In correlation analysis, the two methods showed a very strong and statistically significant correlation (R=0.96, p<0.01). However, in spite of the strong correlation, the ELISA method tended to overestimate the urinary AFM1 concentration compared to the HPLC-FLD method. These results suggest that the competitive ELISA method may be a useful technique for measuring the AFM1 level in high-throughput urine samples, but it needs to be corrected with a regression equation from regression analysis with the HPLC-FLD method.
Activity-guided Screening of Anti-inflammatory Compounds from the Hexane Extracts of Schisandra chinensis Fruit
Choi, Hee Jung ; Choi, Young-Whan ; Baek, Sun-Yong ; Kim, Bong-Seon ; Ahn, Soon Cheol ; Rhee, Moon-Soo ; Yoon, Sik ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 311~318
DOI : 10.5352/JLS.2013.23.2.311
Schisandra chinensis containing a variety of pharmacologically active lignans has been traditionally used in oriental medicine. In this study, anti-inflammatory compounds were screened from the hexane extracts of S. chinensis by activity-guided fractionation. First, we investigated the regulatory effects on the expression of E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) with 38 fractions from the hexane extracts of S. chinensis in human umbilical vein endothelial cells (HUVECs). As a result, SCKH1 among the 38 fractions from the hexane extract of S. chinensis was selected for further analysis based on its unique regulatory effect on cell adhesion molecules, especially on VCAM-1, in LPS-stimulated HUVECs. The subsequent activity-guided fractionation of SCKH1 resulted in the purification of SCKH1PAIBPB, which was found to suppress the expression of VCAM-1, MCP-1, IL-6 and IL-8 in HUVECs stimulated with LPS, and to inhibit the adhesive capacity between HUVECs and monocytes. Taken together, our data indicate that SCKH1PAIBPB can be proposed as an effective anti-inflammatory compound that may have a potential therapeutic use for the prevention and treatment of various inflammatory diseases as well as ischemic vascular diseases.
Various Aggregate Forms of Tryptophan Synthase α-Subunit
Park, Myung Won ; Lim, Woon Ki ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 319~323
DOI : 10.5352/JLS.2013.23.2.319
Protein aggregation can cause diseases and hinder the production of useful recombinant proteins. The present study showed that at least three types of aggregates can be formed from tryptophan synthase
) by varying conditions: (1) an opaque white precipitous aggregate, (2) a transparent gel-like precipitous aggregate, and (3) an unprecipitous aggregate. Macroscopically different aggregate types might suggest different mechanisms underlying aggregation processes.
The Potential 'O-GlcNAc-P'om'
Moon, Il Soo ; Lee, HyunSook ; Lee, Hyung Jong ;
Journal of Life Science, volume 23, issue 2, 2013, Pages 324~331
DOI : 10.5352/JLS.2013.23.2.324
The addition and removal of N-acetylglucosamine (GlcNAc) molecules on serine or threonine residues of a protein is called O-GlcNAcylation. This post-translational modification occurs on both cytoplasmic and nuclear protein, and is fast and reversible as comparable to phosphorylation. In contrast to the phospho-signaling cycles, this emerging moon-lightening signaling is cycled by only two enzymes, O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA). The simple machinery is a good evolutionary adaptation of a cell for quick accommodation to continuously fluctuating intra- and extracellular microenvironments. Rather than "switching" on or off a specific proteins - this would be done by phosphorylation where numerous specific kinases and phosphatases are involved - O-GlcNAcylation would play a "rheostat" which would be much more delicately increase or decrease the efficacy of signal transductions in response to cellular nutrient and stress conditions. Interestingly, recent evidence indicates that O-GlcNAc is further modified by phosphorylation. The O-GlcNAc-P will upgrade the modulation efficiency of cellular processes to continuous 'analogue' level. So far, only one protein AP180 was reported to have O-GlcNAc-P on Thr310. But, proteomic data from our laboratory indicate that there are multiple O-GlcNAc-P proteins, constituting "O-GlcNAc-P'om". This will focus on the possibility of existence of "O-GlcNAc-P'om".