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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 17, Issue 12 - Dec 2007
Volume 17, Issue 11 - Nov 2007
Volume 17, Issue 10 - Oct 2007
Volume 17, Issue 9 - Sep 2007
Volume 17, Issue 8 - Aug 2007
Volume 17, Issue 7 - Jul 2007
Volume 17, Issue 6 - Jun 2007
Volume 17, Issue 5 - May 2007
Volume 17, Issue 4 - Apr 2007
Volume 17, Issue 3 - Mar 2007
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Genomic Organization and Promoter Characterization of the Murine Glial Cell-derived Neurotrophic Factor Inducible Transcription Factor (mGIF) Gene
Kim, Ok-Soo ; Kim, Yong-Man ; Kim, Nam-Young ; Lee, Eo-Jin ; Jang, Min-Kyung ; Lee, Dong-Geun ; Lee, Sang-Hyeon ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 167~173
DOI : 10.5352/JLS.2007.17.2.167
To study the transcriptional mechanisms by which expression of the murine glial cell-derived neurotrophic factor inducible transcription factor (mGIF) gene is regulated, a murine genomic clone was iso-lated using a mGIF cDNA as probe. A 13-kb genomic fragment, which comprises 4-kb upstream of the transcription initiation site was sequenced. The promoter region lacks a TATA box and CAAT box, is rich in G+C content, and has multiple putative binding sites for the transcription factor Spl. The mGIF gene also has consensus sequences for AP2 binding sites. The transcriptional activity of five deletion mutants of a 2.1-kb fragment was analyzed by modulating transcription of the heterologous luciferase gene in the promoterless plasmid pGL2-Basic. All mutants showed significant transcriptional activity in the murine neuroblastoma cell line NB41A3. Transient expression assays suggested the presence of a positive regulator between -213 and -129 while a negative regulator was found in the region between -806 and -214. Relatively strong transcriptional activity was observed in neuronal NB41A3, glial C6 cells and hepatic HepG2, but very weak activity in skeletal muscle C2C12 cells. These findings confirm the tissue-specific activity of the mGIF promoter and suggest that this gene shares structural and functional similarities with the dopamine receptor genes that it regulates.
Regulators affect the Gravitropism and Ethylene Production Induced by Malformin A1 in Maize Root
Hong, Sung-Hyun ; Oh, Seung-Eun ; Kim, Kun-Woo ; Jeong, Hyung-Jin ; Kim, Soon-Young ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 174~178
DOI : 10.5352/JLS.2007.17.2.174
Treatment of malformin A1 is known to increase ethylene production 130% at 4 hr and 56% at 8 hr after treatment in maize root compared to untreated plants. The ethylene production by malformin A1 was maximum level at 4 hr and slowly decreased up to 8 hr. Calcium ion regulators such as A23187 (calcium ionophore) and verapamil (calcium channel blocker) stimulated ethylene production. Treatment of both calcium ion regulators increased about 30% of ethylene production at 4 hr, and 20% at 8 hr. Both calcium ion regulators did not stimulate malformin A1-induced ethylene production at 4 hr as malformin A1 itself did. However, the treatment of calcium ion regulators with malformin A1 maintains the ethylene production for 8 hr. These results suggested that the proper concentration of calcium might need to confer the effect of malformin A1 on the ethylene production. Malformin A1 suppressed the gravitropic curvature of maize root about 58% at 4 hr and 42% at 8 hr compared to control plant. Verapamil inhibited the gravitropic curvature about 54% at 4 hr and 23% at 8 hr compared to control, respectively. But A23187 could not. In addition, verapamil showed more inhibition in malformin A1-induced gravitropic curvature than A23187 in malformin A1 induced. These data suggested that calcium ion regulators affect the malformin A1-induced ethylene production and gravitropic curvature, and give the evidence that calcium ion play an important role in gravitropic curvature in maize root.
High Level Production of human Protein Tyrosine Kinase-6 in Insect Cells Using Drosophila Peptidoglycan Recognition Protein-LB as a fusion protein
Kim, Seul-Ki ; Kim, Han-Ie ; Woo, Jae-Sung ; Cho, Hyun-Soo ; Jung, Yun-Jin ; Lee, Seung-Taek ; Ha, Nam-Chul ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 179~184
DOI : 10.5352/JLS.2007.17.2.179
PTK6, an intracellular protein tyrosine kinase, is significantly overexpressed in a majority of breast cancers and has a role in promoting the proliferation of the cancer cells, but not of normal cells. Here, we report high-level production of the catalytic unit of PTK6 fused with Drosophila peptidoglycan recognition protein (PGRT)-LB, in the baculovirus system. We first found that the PGRP-LB was potentially useful as a fusion partner to increase the yield of heterologous protein in the baculovirus system. The purified recombinant protein exhibited a 1.5-fold activity with much higher yield than the bacterially-expressed protein. The protein expressed in the baculovirus system will be useful for the crystallization to determine its crystal structure helping understand the molecular mechanism of PTK6 and design its inhibitors.
Direct tyrosine phosphorylation of Akt/PKB by epidermal growth factor receptor
Bae, Sun-Sik ; Choi, Jang-Hyun ; Yun, Sung-Ji ; Kim, Eun-Kyung ; Oh, Yong-Suk ; Kim, Chi-Dae ; Suh, Pann-Ghill ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 185~191
DOI : 10.5352/JLS.2007.17.2.185
Akt/PKB plays pivotal roles in many physiological responses such as proliferation, differentiation, apoptosis, and angiogenesis. Here we show that tyrosine phosphorylation of Akt/PKB is essential for the subsequent phosphorylation at
. Tyrosine phosphorylation of Akt/PKB was induced by stimulation of COS-7 cells with epidermal growth factor receptor (EGF) and its phosphorylation was significantly enhanced by constitutive targeting of Akt/PKB to the plasma membrane by myristoylation. Interestingly, incubation of affinity purified Myc-tagged Akt/PKB with purified EGF receptor resulted in tyrosine phosphorylation as well as
phosphorylation of Akt/PKB. In addition, tyrosine-phosphorylated Akt/PKB could directly associate with activated EGF receptor in vitro. Finally, alanine mutation at putative tyrosine phosphorylation site
abolished EGF induced
phosphorylation of wild type as well as constitutively active form of Akt/PKB. Given these results we suggest here that direct tyrosine phosphorylation of Akt/PKB by EGF receptor could be another mechanism of EGF-induced control of many physiological responses.
Role of Rho A and F-actin for uropod formation in T lymphocytes
Lee, Jong-Hwan ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 192~197
DOI : 10.5352/JLS.2007.17.2.192
Two distinct morphological features, leading edge and uropod, in mobile T lymphocyte are crucial for efficient directional movement. The uropod is a unique rear protrusion in migrating lymphocytes, in which several proteins, including CD44, ERM (ezrin/radixin/moesin), and F-actin cytoskeleton are concentrated and concerted. F-actin cytoskeleton is a basic mold for the shape maintenance. Rho A small GTPase acts as cytoskeleton organizer, So far, various pathways potentially can induce the Rho activation. PDZ domain is able to increase active Rho A form (Rho-GTP) level, reorganize F-actin cytoskeleton, disrupts the uropod structure and cell migration was diminished, suggesting that signaling pathways between Rho and F-artin cytoskeleton are related to uropod formation.
A Reliable Protocol for transfection of mature primary hippocampal neurons using a neuron-glia co-culture system
Lee, Hyun-Sook ; Cho, Sun-Jung ; Jung, Yong-Wook ; Jin, Ing-Nyol ; Moon, Il-Soo ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 198~203
DOI : 10.5352/JLS.2007.17.2.198
DNA transfection is a powerful tool for studying gene functions. The
-phosphate precipitation remains one of the most popular and cost-effective transfection techniques. Mature neurons are more resistant to transfection than young ones and most other cell types, and easy to die if microenvironment changes. Here, we report a transfection protocol for mature neurons. The critical modifications are inclusion of glial cells in culture and careful control of
-phosphate precipitation under microscope. Cerebral glial cells were grown until
confluence in DMEM/10% horse serum, which was thereafter replaced with serum-free Neurobasal/Ara-C, and 319 hippocampal neurons were plated onto the glial layer Formation of fine
-phosphate precipitates was induced using Clontech
Mammalian Transfection Kit, and the size (
in diameter) and density(about 10 particles/
) were carefully controlled by the time of incubation in the medium. This modified protocol can be reliably applied for transfection of mature neurons that are maintained longer than two weeks in vitro, resulting in 10-15 healthy transfected neurons per a well of 24-well plates. The efficacy of the protocol was verified by punctate expression of
, a synaptic protein, and diffuse expression of pDsRed2. Our protocol provides a reliable method for transfection of mature neurons in vitro.
Glutamine Residue at 276 of smooth muscle α-tropomyosin is primarily responsible for higher actin affinity
Jung, Sun-Ju ; Cho, Young-Joon ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 204~210
DOI : 10.5352/JLS.2007.17.2.204
Previous reports indicated that the carboxyl terminal residues, glutamine276-threonine277 in particular, were important for actin affinity of the unacetylated smooth
. To determine the role of the glutamine and threonine residues in C-terminal region in actin binding, we constructed mutant striated muscle
(TMs), in which these two residues were individually substituted. These mutant tropomyosins, designated TM18 (HT) and TM19 (QA), were overexpressed in E. coli as an either unacetylated form or Ala-Ser. (AS) dipeptide fusion form, and were analyzed F-actin affinity by cosedimentation. Unacetylated TM19 (QA) bound to actin approximately three times stronger than TM18 (HT) and much stronger than ST (HA). AS/TM19 (QA) showed four times stronger, in actin affinity than AS/ST (HA) while AS/TM14 (QT) bound to actin stronger to some extent than AS/TM18 (HT). These results suggested that the presence of Gln residue at 276 be primarily attributed to higher actin affinity of smooth
Effect of temperature and denaturation conditions on protein folding assisted by GroEL-GroES chaperonin
Bae, Yu-Jin ; Jang, Kyoung-Jin ; Jeon, Sung-Jong ; Nam, Soo-Wan ; Lee, Jae-Hyung ; Kim, Young-Man ; Kim, Dong-Eun ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 211~217
DOI : 10.5352/JLS.2007.17.2.211
The goal of this study is to investigate effects of temperature and co-chaperonin requirement for in vitro protein refolding assisted by E. coli chaperone GroEL under permissive and nonpermissive temperature conditions. In vitro protein refolding of two denatured proteins was kinetically investigated under several conditions in the presence of GroEL. Effects of temperature and GroES-requirement on the process of prevention of protein aggregation and refolding of denatured protein were extensively monitored. We have found that E. coli GroEL chaperone system along with ATP is required for invitro refolding of unfolded polypeptide under nonpermissive temperature of
. However, under permissive condition spontaneous refolding can occur due to lower temperature, which can competes with chaperone-mediated protein refolding via GroEL chaperone system. Thus, GroEL seemed to divert spontaneous refolding pathway of unfolded polypeptide toward chaperone-assisted refolding pathway, which is more efficient protein refolding pathway.
Relationship between HsCRP and Pulse Transit Time
Kim, Yun-Jin ; Min, Hong-Gi ; Kim, Young-Joo ; Jeon, Ah-Young ; Jeon, Gye-Rok ; Ye, Soo-Young ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 218~222
DOI : 10.5352/JLS.2007.17.2.218
The purpose of this study is to evaluate the relationship between high sensitive C-reactive protein (hsCRP) and pulse transit time (PPT). Apparently healthy 233 subjects had been enrolled in the health promotion center of the Pusan National University Hospital from Jan. 29 to Feb. 26, 2004. They had no previous history of diabetes, hypertension and hyperlipidemia. Subjects were categorized according to tertiles of hsCRP level [Group 1: first tertile
, Group 2: second tertile
, Group 3: third tertile
, and Group 4: Fourth tertile
]. PTT body mass index (BMI), total cholesterol (T-C), LDL-cholesterol(LDL-C), blood sugar (BS), systolic blood pressure (sBP) and diastolic blood pressure (dBP) were significantly different among hsCRP groups (p<0.05). HsCRP is positively related with BMI, tryglyceride (TG), LDL, sBP and dBP (p<0.05), and negatively related with PTT and HDL-cholesterol (HDL-C) (p<0.05). PTT is significantly negatively related with hsCRP, T-C, TG, LDL-C, BS, dBP and sBP (p<0.05). The hsCRP and PTT were related before controlling BMI, T-C, LDL-C, sBP, and dBP, but not related after conkolling. The relationship between hsCRP and PTT depends on cardiovascular disease risk factors.
Temporal and Spatial Role of Pupal Stage Specific Cuticle Protein in Artogeia rapae
Shin, Myung-Ja ; Park, Jeong-Nam ; Seo, Eul-Won ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 223~229
DOI : 10.5352/JLS.2007.17.2.223
Present study aims to investigate the topical distribution of pupal stage specific cuticle protein and its temporal and spatial role during the wing formation of Artogeia rapae. ArCP27(27 kd cuticle protein) was identified as pupal stage specific cuticle protein in cuticle tissues and has not shown any qualitative differences by local portions of body. ArCP27 maintained constant concentration just after pupal ecdysis to 5-day old pupal stage but thereafter decreased. In fat body, ArCP27 was found in both thoracic and abdominal fat body from the last larval to pupal stage. In wing cuticle, ArCP27 began to find from 5-day old pupal stage. Immunologically ArCP27 in thoracic and abdominal cuticle has the response against the ArCP27 at 5-day old pupa but since then has no response. But the antibody against ArCP27 has reacted to 5- and 7-day old pupal and adult wing protein.
was not incorporated into ArCP27 in 5- and 7-day old thoracic and abdominal cuticle but was incorporated into ArCP27 in 7-day old wing cuticle and adult wing, suggesting that ArCP27 partly participates the wing cuticle formation by the process of digestion and reabsorption of old cuticle.
Expression of Cu/Zn SOD according to H
in Hepatoma cell line
Kim, Young-Min ; Seo, Won-Sook ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 230~234
DOI : 10.5352/JLS.2007.17.2.230
Oxygen is required for many important aerobic cellular reactions, it may undergo electrontransfer reactions, which generate highly reactive membrane-toxic intermediates (reactive oxygen species, ROS), such as hydrogen peroxide, singlet oxygen, superoxide radical, hydroxyl radical, hydroperoxyl radical, hydroxy ion. Various mechanisms are available to protect cells against damage caused by oxidative free radicals, including scavenging enzyme systems such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). This antioxidant defense system is a very complex and finely tuned system consisting of enzymes capable of detoxifying oxygen radicals as well as low molecular weight antioxidants. In addition, repair and turnover processes help to minimize subcellular damage resulting from free radical attack.
,one of the major ROS, is produced at a high rate as a product of normal aerobic metabolism. The primary cellular enzymatic defense systems against
are the glutathione redox cycle and catalase. From Northern blot analysis of total RNAs from cultured cell with
treatment, various results were obtained. Expression of Cu/Zn SOD decreased when cell passage increased, but the level of the Cu/Zn SOD was scarcely expressed in 35 passage.
AtERF11 is a positive regulator for disease resistance against a bacterial pathogen, Pseudomonas syringae, in Arabidopsis thaliana
Kwon, Tack-Min ; Jung, Yun-Hui ; Jeong, Soon-Jae ; Yi, Young-Byung ; Nam, Jae-Sung ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 235~240
DOI : 10.5352/JLS.2007.17.2.235
AvrRpt2 protein triggers hypersensitive response (HR) and strong disease resistance when it is translocated from a bacterial pathogen Pseudomonas sp. to host plant cells containing a cognate RPS2 resistance protein through Type III Secretion System (TTSS). However, AvrRpt2 protein can function as the effector that suppresses a basal defense and enhances the disease symptom when functional RPS2 resistance protein is absent in the infected plant cells. Using Affymetrix Arabidopsis DNA chip, we found that many genes were specifically regulated by AvrRpt2 protein in the rps2 Arabidopsis mutant. Here, we showed that expression of AtERF11 that is known as a member of B1a subcluster of AP2/ERF transcription factor family was down regulated specifically by AvrRpt2. To determine its function in plant resistance, we also generated the Arabidopsis thaliana transgenic plants constitutively overexpressing AtERF11 under CaMV 355 promoter, which conferred an enhanced resistance against a bacterial pathogen, Pseudomonas syringae pv. tomato DC3000. Thus, these results collectively suggest that AtERF11 plays a role as a positive regulator for disease resistance against biotrophic bacterial pathogen in plant.
Cell Surface Display of Cycloinulooligosaccharide Fructanotransferase Gene in Saccharomyces cerevisiae
Kim, Hyun-Jin ; Lee, Jae-Hyung ; Kim, Hyun-Chul ; Kim, Yeon-Hee ; Kwon, Hyun-Ju ; Nam, Soo-Wan ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 241~247
DOI : 10.5352/JLS.2007.17.2.241
The cycloinulooligosaccharide fructanotransferase (CFTase) gene (cft) from Paenibacillus macerans was subcloned into the surface display vector, pCTcon (GAL1 promoter). The constructed plasmid, pCTECFTN (9.0 kb) was introduced to S. cerevisiae EBY100 cell and then east transformants were selected on the synthetic defined medium lacking uracil and on the inulin containing medium. The surface display of CFTase was confirmed by immunofluorescence microscopy and its enzymatic ability to form cycloinulooligosaccharides(cyclofructans, CFs) from inulin. The total activity of the CFTase was reached about 5.52 unit/1 by cultivation of yeast transformant on YPDG medium. The optimized conditions determined were as follows; pH, 8.0; temperature,
; substrate concentration, 5%; inulin source, Jerusalem artichoke. By the reaction with inulin, CFs consisting of cycloinulohexaose (CF6), cycloinuloheptaose (CF7), and cycloinulooctaose (CF8) were produced and CF6 was the major product.
The Effects of Diesel Exhaust Particulates and Particulate Matters on the Airway Remodeling in the Asthma-induced Mice
Li, Tianzhu ; Lee, Soo-Jin ; Jang, Yang-Ho ; Park, Jun-Hong ; Park, Se-Jong ; Lee, Jeong-Hak ; Choe, Nong-Hoon ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 248~253
DOI : 10.5352/JLS.2007.17.2.248
This research investigated whether exposure of diesel exhaust particulate (DEP) and particulate matter (PM) effects on airway remodeling in asthma induced Balb/c and IL-10 knock out (KO) mouse. Mice were sensitized with intraperitoneal injection with ovalbumin, followed by challenges with intranasal ovalbumin. After that mice placed in inhalation chamber and exposed to DEP and
. The evidence of airway remodeling was assessed by masson's trichrome staining and PAS staining. The stainability of masson's trichrome and PAS reaction were increased in asthma-induced Baltic mice groups compared with control mice groups. More intensive stainability for masson's trichrome and PAS were appeared in the asthma-induced DEP and PM-exposed groups than asthama-induced groups. But, not significantly increased subepithelial fibrosis and the nember of goblet cell hyperplasia in asthma-induced IL-10 KO mice groups and asthma-induced+DEP and PM-exposed IL-10 KO mice than IL-10 KO mice groups. These results indirectly suggesting that exposure to DEP and PM in asthmatic patients might be aggravate clinical symptoms and IL-10 which seems to play a central role in allergic asthma. In conclusion, DEP and PM exposure might have additive effects on the ovalbumin- induced asthma in a murine model.
Biochemical Characterization of Lectin Isolated from Cherry Tomato Fruit
Park, Na-Young ; Lee, Sam-Pin ; Roh, Kwang-Soo ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 254~259
DOI : 10.5352/JLS.2007.17.2.254
Biochemical characterization of lectin isolated from fruit of cherry tomato through neutral saline extraction, ammonium sulfate precipitation, and affinity chromatography on Sephadex G-200 was studied. The lectin was agglutinated by trypsin-treated human ABO erythrocytes, and the most pronounced activity of agglutination was observed at B type erythrocyte. The analysis of the lectin by SDS-PAGE showed the high intensity band with molecular weights of 10.7 kDa. The optimal temperature and thermal stability of the lectin was
, respectively. The maximal pH of this lectin was pH 7.2.
Effects of Electron-Beam Irradiation on the Physico-chemical Properties of Hanwoo Meat
Park, Tae-Seon ; Park, Gu-Bu ; Oh, Seong-Hyeon ; Lee, Jeong-Il ; Sin, Taek-Sun ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 260~265
DOI : 10.5352/JLS.2007.17.2.260
This study was carried out to investigate the effect of Electron Beam irradiation on physico-chemical characteristics of Hanwoo meat. A total of sir beef carcasses
that were quality grade
(marbling score No. 7, meat color No. 4, maturity No. 1, texture No. 1) was purchased at the commercial slaughter house. The carcasses were transported and washed using high pressure water, and pasteurized with 50% ethyl alcohol in the laboratory. After the carcasses were deboned and trimmed, loin and round were taken out to make steak (1.5 cm thickness) or patty respectively. Samples were wrap or vacuum packaged and irradiated with 0, 3, 4.5, 6 and 7.5 kGy using electron-beam accelerator. Irradiated samples were used to measure pH, moisture, crude protein, crude fat, and meat color. There was no significant (p>0.05) difference in pH between vacuum packaged (VP) and wrap packaged (WP) treatment, and the pH was not changed by electron-beam irradiation levels. Both control and irradiated treatments of steak showed higher tendency in moisture content. In crude protein content, control was higher than irradiated treatment in steak, but there were no difference in patty. Lightness (
) of meat color has no difference between irradiated and non-irradiated treatment (p>0.05). The value of redness and Yellowness of meat was dropped by increasing irradiation (p<0.05), but there was no difference between control and 3 kGy treatment (p<0.05).
Spectrophotometric Determination of Bisphenol A by Complexation with Ferricyanide and Ferric chloride solution
Kum, Eun-Joo ; Ryu, Hee-Young ; Kwon, Gi-Seok ; Sohn, Ho-Yong ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 266~271
DOI : 10.5352/JLS.2007.17.2.266
Bisphenol A (BPA) has been widely used as a monomer for production of epoxy resins and polycarbonate plastics. The annual production of BPA exceeds 640,000 metric tons in worldwide. BPA, a suspected phenolic endocrine disrupter, is moderately soluble and frequently detected in industrial wastewater. To date, HPLC and GC has been used for BPA analysis. However, HPLC and GC-analysis need high operation lost, experts, and an elaborate pre-treatment of samples, and is difficult to apply on-time and mass analysis. Therefore, simple, mass and rapid detection of BPA in environments is necessary. In the present study, spectrophotometric method of BPA quantification was developed. Based on blue-color product formation with BPA and ferric chloride/ferricyanide under the optimized conditions, the standard curve was acquired
. Using an established method, the BPA contents in the soil extract, and different water samples and living products, including disposable syringe, cup and plastic tube, were analyzed. The results suggested that the method is useful for BPA determination from different massive samples. Since the BPA metabolites, nontoxic 4-hydroxyacetophenone or 4-hydroxybenzaldehyde, did not form blue-color product, this method is also useful to screen a microorganism for BPA bioremediation.
Isolation of Pseudoalteromonas sp. HJ 47 from Deep Sea Water of East Sea and Characterization of its Extracellular Protease
Cha, In-Tae ; Lim, Hayung-Joon ; Roh, Dong-Hyun ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 272~278
DOI : 10.5352/JLS.2007.17.2.272
Proteases are enzymes that break peptide bonds between amino acids of other proteins and occupy a crucial position with respect to their applications in both physiological and commercial fields. In order to screen new source of protease, bacteria producing extracellular proteases at low temperature were isolated from deep sea water of East Sea, Korea. A bacterium showing the best growth rate and production of an extracellular protease at low temperature was designated HJ 47. The DNA sequence analysis of the 16S rRNA gene, phenotypic tests and morphology led to the placement of this organism in the genus Pseudoalteromonas. Although maximal growth was observed at
, enzyme production per culture time was maximum at
. At this temperature, extracellluar protease production was detected from the end of the exponential phage to stationary phase, and maximal at 15 hours after initial production. The optimum temperature and pH of the protease were found to be
Detection of Mycoplasmas DNA in the Cancer and the Normal Tissues from the Patients with Gastric and Colon Cancer
Chang, Myung-Woong ; Shin, Hyun-Chul ; Park, In-Dal ; Kim, Kwang-Hyuk ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 279~285
DOI : 10.5352/JLS.2007.17.2.279
Detection of Mycoplasma DNA from the 30 cases of cancer tissues and the normal tissues surrounding the cancer tissues obtained from the patients with gastric cancer and the other 30 cases of cancer tissues and the normal tissues surrounding the cancer tissues obtained from the patients with colon cancer were evaluated by polymerase chain reaction(PCR). The PCR products were sequenced using an ABI 377 automatic DNA sequencer, and these sequences were confirmed by comparing sequences with the database of the National Center for Biotechnology Information BLAST network server. Mycoplasmas DNA were defected in 18 (60%) cases of normal tissues which were around gastric cancer and were 13 (43.3%) cases of gastric cancer tissues. Mycoplasmas DNA were detected in 15(50%) cases of normal tissues which were around colon cancer and 12 (40%) cases of colon cancer tissues. The M. faucium, M. subdolum, M. salivarium, M. auris, M. hyosynoviae, and M. conjunctivae were detected from the gastric cancer tissues. The M. faucium, M. subdolum,, M. salivarium, M. auris, M. hyosynoviae, M. bovigenitalium and M. pulmonis were detected from the normal tissues around gastric cancer. The M. faucium, M. subdolum, M. salivarium, M. auris, M. hyosynoviae, M. synoviae M. bovigenitalium, M. gallinarum, and M. moatsii were detected from the colon cancer. The M. faucium, M. subdolum, M. salivarium, M. auris, M. hyosynoviae, M. bovis, M. opalescens, M. bovigenitalium, M. gallinarum, and M. moatsii were detected from the normal tissues around the colon cancer. These results suggest that Mycoplasmas infection may not correlate with gastric cancer and colon cancer, because of the detection rate of Mycoplasmas DNA were not significantly differences between normal and cancer tissues from the patients.
Elution Profiles of Volatile Compounds and Free Amino Acids during Alcohol Soaking of Garlic(Allum sativum L.)
Lee, Young-Guen ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 286~292
DOI : 10.5352/JLS.2007.17.2.286
Free amino acids and volatile compounds of fresh garlic and its liqueur were investigated to search elution profile of those components as basic data for development of garlic liqueur. The garlic was soaked in 20% alcohol solution and then sampled every week for 5 weeks. The major free amino acids were L-aspartic acid, L-glutamic acid, L-arginine, L-alanine, L-proline, L-asparagine and L-serine. Neutral amino acids such as L-threonine, L-proline, L-valine and L-leucine, and aromatic amino acids such as tyrosine and phenylalanine were eluted over 80% of those content in fresh garlic after 3 weeks of soaking, but acidic, basic and sulfur containing amino acids were below 80% even after 5 weeks. Sulfide compounds such as diallyl trisulfide, diallyl disulfide, methyl allyl disulfide, 2-vinyl-4H-1,3-dithi in, 3-vinyl-3,4-dihydro-1,2-dithiin, 3,5-diethyl-1,24-trithiolane, isobutyl isothiocyanate and diallyl sulfide were identified as major volatile compounds of fresh garlic by using GC/MS. Among volatile compounds of fresh garlic, allyl alcohol, diallyl disulfide, 3,5-diethyl-1,2,4-trithiolane, diallyl trisulfide and 3,4-dimethoxy furan were eluted to liqueur, but those compounds except 3,5-diethyl-1,2,4-trithiolane were lowered in liqueur during soaking. Furfural, 5-methylfurfural, 5-hydroxymethylfurfural, dimethyl pyrazine, furfuryl alcohol, 3-hydroxy-2-bytanone and 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyr-an-4-one were generated newly and their content increased in liqueur during soaking.
Production of Green Fluorescent Protein (GFP) from Transgenic Rice Cell Suspension Culture
Lee, Jae-Hwa ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 293~297
DOI : 10.5352/JLS.2007.17.2.293
Green fluorescent protein (GFP) is an attractive reporter for bioprocess monitoring. A fluorescence-based method was developed to quantify GFP levels in transgenic plants and protein extracts. In this study, GFP was produced and secreted from suspension cells derived from transgenic rice. The RAmy3E promoter placed before the GFP gene controlled by sugars such as sucrose. The effects of sucrose concentration on the secretion of GFP and total protein into the medium were investigated in batch suspension culture. It was possible, therefore, to induce the expression of the GFP by removing sucrose from the cultured media or by allowing the rice suspension cells to deplete sucrose catabolically. The dry cell weight (7.06 g/L) and GFP level were detected as highest at 12%, 3% sucrose after 20 day culture, respectively. However secreted GFP fluorescence at the other sucrose concentrations (6%, 12%, 18% and 24%) were a little amount in media.
Identification and Chararterization of Stationary-phase Specific Cytosolic Protein in Salmonella typhimurium
Yoo, Ah-Young ; Kim, Young-Hee ; Yu, Jong-Earn ; Kim, Sam-Woong ; Baik, Hyung-Suk ; Kang, Ho-Young ;
Journal of Life Science, volume 17, issue 2, 2007, Pages 298~304
DOI : 10.5352/JLS.2007.17.2.298
Salmonella is facultative intracellular pathogen that can survive and replicate in macrophages even though these cells are equipped with a plethora of anti-microbial mechanisms. To survive in this hostile intracellular environment, Salmonella has evolved numerous defense mechartisms. An approximately 20 kDa protein was detected as a stationary-phase specific protein band in cytosolic fraction. It was identified as a DNA binding protein in stationary phase (Dps) by analysis of MALDI-TOF assay. It has been known that Dps, the protein produced in the stationary phase of bacteria, allows DNA to form chromatin by binding to DNA nonspecifically and protects DNA from reactive oxidative species (ROS). For further study, Dps specific polyclonal antibodies were generated by injection of purified Dps protein into rabbit. To examine the Finfluence of several regulatory proteins in the expression dps gene, Dps protein level in various S. typhimurium mutants defecting regulatory proteins were investigated by Westernblot using Dps specific polyclonal antibodies.