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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of Microbiology and Biotechnology
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Journal DOI :
The Korean Society for Applied Microbiology and Biotechnology
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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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Biomedical Application of Phosphoproteomics in Neurodegenerative Diseases
Bahk, Young Yil ; Mohamed, Bari ; Kim, Young Jun ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 279~288
DOI : 10.4014/jmb.1301.01027
Phosphorylation and dephosphorylation of proteins trigger many critical events involved in cellular response, such as regulation of enzymatic activity, protein conformational change, protein-protein interaction, and cellular localization. Any malfunction of protein phosphorylation leads to a diseased state such as diabetes, cancer, and even neurodegenerative diseases. In order to comprehend the molecular view of the complex biological processes of these diseases in depth, very sensitive and detailed analytical methods are necessary for identification of the phosphorylated residues in a protein. As part of these efforts, phosphoproteomics has been developed and applied for the elucidation of neurodegenerative diseases. In this review, we present a brief summary of phosphoproteomics approaches that are now routinely used in biomedical research, and describe the biomedical application of phosphoproteomics especially in Alzheimer's and other neurodegenerative diseases.
Improved Methodology for Identification of Cryptomonads: Combining Light Microscopy and PCR Amplification
Xia, Shuang ; Cheng, Yingyin ; Zhu, Huan ; Liu, Guoxiang ; Hu, Zhengyu ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 289~296
DOI : 10.4014/jmb.1203.03057
Cryptomonads are unicellular, biflagellate algae. Generally, cryptomonad cells cannot be preserved well because of their fragile nature, and an improved methodology should be developed to identify cryptomonads from natural habitats. In this study, we tried using several cytological fixatives, including glutaraldehyde, formaldehyde, and their combinations to preserve field samples collected from various waters, and the currently used fixative, Lugol's solution was tested for comparison. Results showed that among the fixatives tested, glutaraldehyde preserved the samples best, and the optimal concentration of glutaraldehyde was 2%. The cell morphology was well preserved by glutaraldehyde. Cells kept their original color, volume, and shape, and important taxonomic features such as furrow/gullet complex, ejectosomes, as well as flagella could be observed clearly, whereas these organelles frequently disappeared in Lugol's solution preserved samples. The osmotic adjustments and buffers tested could not preserve cell density significantly higher. Statistical calculation showed the cell density in the samples preserved by 2% glutaraldehyde remained stable after 43 days of the fixation procedure. In addition, DNA was extracted from glutaraldehyde preserved samples by grinding with liquid nitrogen and the 18S rDNA sequence was amplified by PCR. The sequence was virtually identical to the reference sequence, and phylogenetic analyses showed very close relationship between it and sequences from the same organism. To sum up, the present study demonstrated that 2% unbuffered glutaraldehyde, without osmotic adjustments, can preserve cryptomonads cells for identification, in terms of both light microscopy and phylogenetic analyses based on DNA sequences.
Correlation Between Sorangium cellulosum Subgroups and Their Potential for Secondary Metabolite Production
Lee, Chayul ; An, Dongju ; Lee, Hanbit ; Cho, Kyungyun ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 297~303
DOI : 10.4014/jmb.1210.10054
Phylogenetic analysis of the groEL1 and xynB1 gene sequences from Sorangium cellulosum strains isolated in Korea previously revealed the existence of at least 5 subgroups (A-E). In the present study, we used sequence analysis of polymerase chain reaction-amplified biosynthetic genes of strains from the 5 subgroups to indicate correlations between S. cellulosum subgroups and their secondary metabolic gene categories. We detected putative biosynthetic genes for disorazol, epothilone, ambruticin, and soraphen in group A, group C, group D, and group E strains, respectively. With the exception of KYC3204, culture extracts from group A, group B, and group C strains exhibited no noticeable antimicrobial inhibitory activities. By contrast, culture extracts from group D strains inhibited the growth of Candida albicans, whereas culture extracts from group E strains inhibited the growth of C. albicans and Staphylococcus aureus. High performance liquid chromatography analysis of the culture extracts from the strains of each subgroup revealed unique peak patterns. Our findings indicate the existence of at least 5 subgroups of S. cellulosum strains, each of which has the potential to produce a unique set of secondary metabolites.
Development of a Genome-Wide Random Mutagenesis System Using Proofreading-Deficient DNA Polymerase
in the Methylotrophic Yeast Hansenula polymorpha
Kim, Oh Cheol ; Kim, Sang-Yoon ; Hwang, Dong Hyeon ; Oh, Doo-Byoung ; Kang, Hyun Ah ; Kwon, Ohsuk ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 304~312
DOI : 10.4014/jmb.1211.11048
The thermotolerant methylotrophic yeast Hansenula polymorpha is attracting interest as a potential strain for the production of recombinant proteins and biofuels. However, only limited numbers of genome engineering tools are currently available for H. polymorpha. In the present study, we identified the HpPOL3 gene encoding the catalytic subunit of DNA polymerase
of H. polymorpha and mutated the sequence encoding conserved amino acid residues that are important for its proofreading 3'
5' exonuclease activity. The resulting
gene encoding the error-prone proofreading-deficient DNA polymerase
was cloned under a methanol oxidase promoter to construct the mutator plasmid pHIF8, which also contains additional elements for site-specific chromosomal integration, selection, and excision. In a H. polymorpha mutator strain chromosomally integrated with pHIF8, a
mutant resistant to 5-fluoroorotic acid was generated at a 50-fold higher frequency than in the wild-type strain, due to the dominant negative expression of
. Moreover, after obtaining the desired mutant, the mutator allele was readily removed from the chromosome by homologous recombination to avoid the uncontrolled accumulation of additional mutations. Our mutator system, which depends on the accumulation of random mutations that are incorporated during DNA replication, will be useful to generate strains with mutant phenotypes, especially those related to unknown or multiple genes on the chromosome.
Diversity and Active Mechanism of Fengycin-Type Cyclopeptides from Bacillus subtilis XF-1 Against Plasmodiophora brassicae
Li, Xing-Yu ; Mao, Zi-Chao ; Wang, Yue-Hu ; Wu, Yi-Xing ; He, Yue-Qiu ; Long, Chun-Lin ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 313~321
DOI : 10.4014/jmb.1208.08065
Bacillus subtilis XF-1, a strain with demonstrated ability to control clubroot disease caused by Plasmodiophora brassicae, was studied to elucidate its mechanism of antifungal activity against P. brassicae. Fengycin-type cyclopeptides (FTCPs), a well-known class of compounds with strong fungitoxic activity, were purified by acid precipitation, methanol extraction, and chromatographic separation. Eight homologs of fengycin, seven homologs of dehydroxyfengycin, and six unknown FTCPs were characterized with LC/ESI-MS, LC/ESI-MS/MS, and NMR. FTCPs (250
) were used to treat the resting spores of P. brassicae (
) by detecting leakage of the cytoplasm components and cell destruction. After 12 h treatment, the absorbencies at 260 nm (
) and at 280 nm (
) increased gradually to approaching the maximum of absorbance, accompanying the collapse of P. brassicae resting spores, and nearly no complete cells were observed at 24 h treatment. The results suggested that the cells could be cleaved by the FTCPs of B. subtilis XF-1, and the diversity of FTCPs was mainly attributed to a mechanism of clubroot disease biocontrol.
Expression and Purification of Human Farnesoid X Receptor-Ligand Binding Domain as Soluble Form Using a Dual Cistronic Expression Vector
Kang, Hyun ; Ye, Micheal B. ; Bahk, Young Yil ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 322~328
DOI : 10.4014/jmb.1212.12014
In this study, we show the expression and purification of the human recombinant farnesoid X receptor (FXR)- ligand binding domain (LBD) protein in E. coli using a double cistronic vector, pACYCDuet-1, as a soluble form. We describe here the expression and characterization of a biologically active
. When expressed in the influence of bacterial promoters (
) of the single cistronic expression vectors, the human recombinant
was found to be totally insoluble. However, by using a double cistronic expression vector, we were able to obtain the human recombinant
in a soluble form. To allow for biological activities, we have subcloned into the pACYCDuet-1 vector, expressed in E. coli cells at some optimized conditions, and purified and characterized the human recombinant active
proteins using the fluorescence polarization assay. This suggests that the expression of FXR-LBD in a double cistronic vector improves its solubility and probably assists its correct folding for the biologically active form of the proteins. We suggest that this may represent a new approach to high expression of other nuclear receptors and may be useful as well for other classes of heterodimeric protein partners.
Identification of Novel Irreversible Inhibitors of UDP-N-Acetylglucosamine Enolpyruvyl Transferase (MurA) from Haemophilus influenzae
Han, Seong-Gu ; Lee, Won-Kyu ; Jin, Bong-Suk ; Lee, Ki-In ; Lee, Hyeong Ho ; Yu, Yeon Gyu ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 329~334
DOI : 10.4014/jmb.1210.10053
Uridinediphospho-N-acetylglucosamine enolpyruvyl transferase (MurA, E.C. 18.104.22.168) is an essential bacterial enzyme that catalyzes the first step of the cell wall biosynthetic pathway, which involves the transfer of an enolpyruvyl group from phosphoenolpyruvate to uridinediphospho-Nacetylglucosamine. In this study, novel inhibitors of Haemophilus influenzae MurA (Hi MurA) were identified using high-throughput screening of a chemical library from the Korea Chemical Bank. The identified compounds contain a quinoline moiety and have much lower effective inhibitory concentrations (
) than fosfomycin, a wellknown inhibitor of MurA. These inhibitors appear to covalently modify the sulfhydryl group of the active site cysteine (C117), since the C117D mutant Hi MurA was not inhibited by these compounds and excess dithiothreitol abolished their inhibitory activities. The increased mass value of Hi MurA after treatment with the identified inhibitor further confirmed that the active-site cysteine residue of Hi MurA is covalently modified by the inhibitor.
Fuzzy Logic Control of Rotating Drum Bioreactor for Improved Production of Amylase and Protease Enzymes by Aspergillus oryzae in Solid-State Fermentation
Sukumprasertsri, Monton ; Unrean, Pornkamol ; Pimsamarn, Jindarat ; Kitsubun, Panit ; Tongta, Anan ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 335~342
DOI : 10.4014/jmb.1204.04038
In this study, we compared the performance of two control systems, fuzzy logic control (FLC) and conventional control (CC). The control systems were applied for controlling temperature and substrate moisture content in a solidstate fermentation for the biosynthesis of amylase and protease enzymes by Aspergillus oryzae. The fermentation process was achieved in a 200 L rotating drum bioreactor. Three factors affecting temperature and moisture content in the solid-state fermentation were considered. They were inlet air velocity, speed of the rotating drum bioreactor, and spray water addition. The fuzzy logic control system was designed using four input variables: air velocity, substrate temperature, fermentation time, and rotation speed. The temperature was controlled by two variables, inlet air velocity and rotational speed of bioreactor, while the moisture content was controlled by spray water. Experimental results confirmed that the FLC system could effectively control the temperature and moisture content of substrate better than the CC system, resulting in an increased enzyme production by A. oryzae. Thus, the fuzzy logic control is a promising control system that can be applied for enhanced production of enzymes in solidstate fermentation.
Efficient Enantioselective Synthesis of (R)-[3,5-Bis(trifluoromethyl)phenyl] Ethanol by Leifsonia xyli CCTCC M 2010241 Using Isopropanol as Co- Substrate
Ouyang, Qi ; Wang, Pu ; Huang, Jin ; Cai, Jinbo ; He, Junyao ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 343~350
DOI : 10.4014/jmb.1203.03047
(R)-[3,5-Bis(trifluoromethyl)phenyl] ethanol is a key chiral intermediate for the synthesis of aprepitant. In this paper, an efficient synthetic process for (R)-[3,5- bis(trifluoromethyl)phenyl] ethanol was developed via the asymmetric reduction of 3,5-bis(trifluoromethyl) acetophenone, catalyzed by Leifsonia xyli CCTCC M 2010241 cells using isopropanol as the co-substrate for cofactor recycling. Firstly, the substrate and product solubility and cell membrane permeability of biocatalysts were evaluated with different co-substrate additions into the reaction system, in which isopropanol manifested as the best hydrogen donor of coupled NADH regeneration during the bioreduction of 3,5-bis(trifluoromethyl) acetophenone. Subsequently, the optimization of parameters for the bioreduction were undertaken to improve the effectiveness of the process. The determined efficient reaction system contained 200mM of 3,5-bis(trifluoromethyl) acetophenone, 20% (v/v) of isopropanol, and 300 g/l of wet cells. The bioreduction was executed at
and 200 rpm for 30 h, and 91.8% of product yield with 99.9% of enantiometric excess (e.e.) was obtained. The established bioreduction reaction system could tolerate higher substrate concentrations of 3,5- bis(trifluoromethyl) acetophenone, and afforded a satisfactory yield and excellent product e.e. for the desired (R)-chiral alcohol, thus providing an alternative to the chemical synthesis of (R)-[3,5-bis(trifluoromethyl)phenyl] ethanol.
-Glucosidase Production by a Strain of Stereum hirsutum and Its Application in Enzymatic Saccharification
Ramachandran, Priyadharshini ; Nguyen, Ngoc-Phuong-Thao ; Choi, Joon-Ho ; Kang, Yun Chan ; Jeya, Marimuthu ; Lee, Jung-Kul ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 351~356
DOI : 10.4014/jmb.1210.10060
-glucosidase (BGL)-producing strain, Stereum hirsutum, was identified and isolated and showed a maximum BGL activity (10.4 U/ml) when cultured with Avicel and tryptone as the carbon and nitrogen sources, respectively. In comparison with other BGLs, BGL obtained from S. hirsutum showed a higher level of activity to cellobiose (
= 172 U/mg, and
= 281/s). Under the optimum conditions (600 rpm,
, and pH 6.0), the maximum BGL activity of 10.4 U/ml with the overall productivity of 74.5 U/l/h was observed. BGL production was scaled up from a laboratory scale (7-L fermenter) to a pilot scale (70-L fermenter). When S. hirsutum was cultured in fed-batch culture with rice straw as the carbon source in a 70-L fermenter, a comparable productivity of 78.6 U/l/h was obtained. Furthermore, S. hirsutum showed high levels of activity of other lignocellulases (cellobiohydrolase, endoglucanase, xylanase, and laccase) that are involved in the saccharification of biomasses. Application of S. hirsutum lignocellulases in the hydrolysis of Pinus densiflora and Catalpa ovata showed saccharification yields of 49.7% and 43.0%, respectively, which were higher than the yield obtained using commercial enzymes.
Spontaneous Release of Bacteriophage Particles by Lactobacillus rhamnosus Pen
Jarocki, Piotr ; Podlesny, Marcin ; Pawelec, Jaroslaw ; Malinowska, Agata ; Kowalczyk, Sylwia ; Targonski, Zdzislaw ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 357~363
DOI : 10.4014/jmb.1207.07037
The identification of bacteriophage proteins on the surface of Lactobacillus rhamnosus Pen was performed by LC-MS/MS analysis. Among the identified proteins, we found a phage-derived major tail protein, two major head proteins, a portal protein, and a host specificity protein. Electron microscopy of a cell surface extract revealed the presence of phage particles in the analyzed samples. The partial sequence of genes encoding the major tail protein for all tested L. rhamnosus strains was determined with specific primers designed in this study. Next, RT-PCR analysis allowed detection of the expression of the major tail protein gene in L. rhamnosus strain Pen at all stages of bacterial growth. The transcription of genes encoding the major tail protein was also proved for other L. rhamnosus strains used in this study. The present work demonstrates the spontanous release of prophage-encoded particles by a commercial probiotic L. rhamnosus strain, which did not significantly affect the bacterial growth of the analyzed strain.
Statistical Optimization for Monacolin K and Yellow Pigment Production and Citrinin Reduction by Monascus purpureus in Solid-State Fermentation
Jirasatid, Sani ; Nopharatana, Montira ; Kitsubun, Panit ; Vichitsoonthonkul, Taweerat ; Tongta, Anan ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 364~374
DOI : 10.4014/jmb.1206.06068
Monacolin K and yellow pigment, produced by Monascus sp., have each been proven to be beneficial compounds as antihypercholesterolemic and anti-inflammation agents, respectively. However, citrinin, a human toxic substance, was also synthesized in this fungus. In this research, solidstate fermentation of M. purpureus TISTR 3541 was optimized by statistical methodology to obtain a high production of monacolin K and yellow pigment along with a low level of citrinin. Fractional factorial design was applied in this study to identify the significant factors. Among the 13 variables, five parameters (i.e., glycerol, methionine, sodium nitrate, cultivation time, and temperature) influencing monacolin K, yellow pigment, and citrinin production were identified. A central composite design was further employed to investigate the optimum level of these five factors. The maximum production of monacolin K and yellow pigment of 5,900 mg/kg and 1,700 units/g, respectively, and the minimum citrinin concentration of 0.26 mg/kg were achieved in the medium containing 2% glycerol, 0.14% methionine, and 0.01% sodium nitrate at
for 16 days of cultivation. The yields of monacolin K and yellow pigment were about 3 and 1.5 times higher than the basal medium, respectively, whereas citrinin was dramatically reduced by 36 times.
Isolation of a Korean Domestic Microalga, Chlamydomonas reinhardtii KNUA021, and Analysis of Its Biotechnological Potential
Hong, Ji Won ; Jeong, Jieun ; Kim, Sung Hong ; Kim, Sunghwan ; Yoon, Ho-Sung ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 375~381
DOI : 10.4014/jmb.1111.11073
A freshwater microalga, Chlamydomonas reinhardtii KNUA021, was characterized for its potential as a biochemical feedstock. Its optimal growth was observed when the culture was incubated at
and pH 9.4. However, the isolate was capable of survival and growth under a variety of temperatures (10-
) and pH (pH 4.0-12.0) conditions. The total lipid content of the isolate was 21.7% of dry weight and it was found that a high-value fatty alcohol, hexadecenol (
), was autotrophically produced by strain KNUA021. In addition, a nutritionally important
-linolenic acid, ALA) was also identified in this photosynthetic microorganism as one of the major fatty acids. Hence, C. reinhardtii KNUA021 appears to show promise for use in the production of microalgae-based biochemicals.
Syntrophic Propionate Degradation Response to Temperature Decrease and Microbial Community Shift in an UASB Reactor
Ban, Qiaoying ; Li, Jianzheng ; Zhang, Liguo ; Jha, Ajay Kumar ; Zhang, Yupeng ; Ai, Binling ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 382~389
DOI : 10.4014/jmb.1210.10008
Propionate is an important intermediate product during the methane fermentation of organic matter, and its degradation is crucial for maintaining the performance of an anaerobic digester. In order to understand the effect of temperature on propionate degradation, an upflow anaerobic sludge blanket (UASB) reactor with synthetic wastewater containing propionate as a sole carbon source was introduced. Under the hydraulic retention time (HRT) of 10 h and influent propionate of 2,000 mg/l condition, propionate removal was above 94% at 30-
, whereas propionate conversion was inhibited when temperature was suddenly decreased stepwise from
, and then to
. After a long-term operation, the propionate removal at
resumed to the value at 30-
, whereas that at
was still lower than the value at
by 8.1% and 20.7%, respectively. Microbial community composition analysis showed that Syntrophobacter and Pelotomaculum were the major propionate-oxidizing bacteria (POB), and most POB had not changed with temperature decrease in the UASB. However, two POB were enriched at
, indicating they were low temperature tolerant. Methanosaeta and Methanospirillum were the dominant methanogens in this UASB and remained constant during temperature decrease. Although the POB and methanogenic composition hardly changed with temperature decrease, the specific
removal rate of anaerobic sludge (SCRR) was reduced by 21.4%-46.4% compared with the control (
) in this system.
Characterization of a Blend-Biosurfactant of Glycolipid and Lipopeptide Produced by Bacillus subtilis TU2 Isolated from Underground Oil-Extraction Wastewater
Cheng, Fangyu ; Tang, Cheng ; Yang, Huan ; Yu, Huimin ; Chen, Yu ; Shen, Zhongyao ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 390~396
DOI : 10.4014/jmb.1207.09020
Biosurfactants have versatile properties and potential industrial applications. A new producer, B. subtilis TU2, was isolated from the underground oil-extraction wastewater of Shengli Oilfield, China. Preliminary flask culture showed that the titer of biosurfactant obtained from the broth of TU2 was ~1.5 g/l at 48 h (718 mg/l after purification), with a reduced surface tension of 32.5 mN/m. The critical micelle concentration was measured as 50 mg/l and the surface tension maintained stability in solution with 50 g/l NaCl and 16 g/l
after 5 days of incubation at
. FT-IR spectra exhibited the structure information of both glycolipid and lipopeptide. MALDI-TOF-MS analyses confirmed that the biosurfactant produced by B. subtilis TU2 was a blend of glycolipid and lipopeptide, including rhamnolipid, surfactin, and fengycin. The blended biosurfactant showed 86% of oil-washing efficiency and fine emulsification activity on crude oil, suggesting its potential application in enhanced oil recovery.
-1,4-Xylanase with Exo-Enzyme Activity Produced by Paenibacillus xylanilyticus KJ-03 and Its Cloning and Characterization
Park, Dong-Ju ; Lee, Yong-Suk ; Chang, Jie ; Fang, Shu-Jun ; Choi, Yong-Lark ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 397~404
DOI : 10.4014/jmb.1212.12017
Paenibacillus xylanilyticus KJ-03 was isolated from soil samples obtained from a field with Amorphophallus konjac plants. A gene encoding xylanase was isolated from KJ-03 and cloned using a fosmid library. The xynA gene encodes xylanase; it consists of 1,035 bp and encodes 345 amino acids. The amino acid sequence deduced from the P. xylanilyticus KJ-03 xylanase showed 81% and 69% identities with those deduced from the P. polymyxa E681 and Paenibacillus sp. HPL-001 xylanases, respectively. The xynA gene comprises a single domain, consisting of a catalytic domain of the glycosyl hydrolase (GH) 10 family. The xynA gene was expressed in Escherichia coli BL21 (trxB), and the recombinant xylanase was purified by Niaffinity chromatography. The purified xylanase showed optimum activity with birchwood xylan as a substrate at
and pH 7.4. Treatment with
showed a slight decrease in XynA activity; however, treatment with 5 mM
completely inhibited its activity. The results of the thin layer chromatography analysis indicated that the major hydrolysis product was xylobiose and small amounts of xylose and xylotriose. XynA showed increased activity with oat spelt xylan and birchwood xylan, but showed only slight activity with locust bean gum.
Functions of Monocyte Chemotactic Protein-3 in Transgenic Mice Fed a High-Fat, High-Cholesterol Diet
An, So Jung ; Jung, Un Ju ; Choi, Myung-Sook ; Chae, Chan Kyu ; Oh, Goo Taek ; Park, Yong Bok ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 405~413
DOI : 10.4014/jmb.1210.10057
Monocyte chemotactic protein-3 (MCP-3), a chemokine that is in a superfamily of structurally related small chemotactic cytokines involved in leukocyte trafficking, is regarded as a key factor in atherogenesis. In this study, we examined the changes in atherogenic parameters including hepatic lipid accumulation and oxidative balance in MCP- 3-overexpressing transgenic mice (MCP-3 mice) under atherogenic conditions. To induce an extreme atherogenic condition, mice were fed a high-fat, high-cholesterol (HFHC) diet for 12 weeks. The body weight and food intake were not changed by MCP-3 overexpression in the aorta. On a HFHC diet, the MCP-3 mice had higher plasma levels of total cholesterol and a higher atherogenic index compared with wild-type mice, although there were no differences in the plasma HDL-cholesterol and triglyceride levels. Furthermore, an increase in lipid accumulation was observed in the aortas as well as the livers of the HFHC diet-fed MCP-3 mice compared with wild-type mice. The activities of antioxidant enzymes increased in the livers of the HFHC diet-fed MCP-3 mice, whereas supplementation with antioxidants, naringin and hesperidin, reversed the activities of the hepatic antioxidant enzymes in HFHC diet-fed MCP-3 mice, indicating that there might be more oxidative damage to the tissues in the HFHC diet-fed MCP-3 mice leading to progression towards atherosclerosis and hepatic steatosis. Microarray analyses of the aorta revealed atherosclerosis-, PPARs-, lipoprotein receptor, and apolipoprotein-related genes that were affected by the HFHC diet in MCP-3 mice. These findings suggest that aortic MCP-3 overexpression may contribute to the development of atherosclerosis and hepatic steatosis under atherogenic conditions.
Lactobacillus plantarum HY7712 Ameliorates Cyclophosphamide-Induced Immunosuppression in Mice
Jang, Se-Eun ; Joh, Eun-Ha ; Lee, Ho-Yong ; Ahn, Young-Tae ; Lee, Jung-Hee ; Huh, Chul-Sung ; Han, Myung Joo ; Kim, Dong-Hyun ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 414~421
DOI : 10.4014/jmb.1210.10010
Lactic acid bacteria (LAB) in fermented foods have attracted considerable attention recently as treatment options for immune diseases, the incidence of which has been increasing worldwide. The ability of 500 strains of LAB, isolated from kimchi, to induce TNF-
production in peritoneal macrophages was investigated. Lactobacillus plantarum HY7712 most strongly induced TNF-
production as well as NF-
activation. However, HY7712 inhibited NF-
activation in LPS-stimulated peritoneal macrophages. When HY7712 was orally treated in cyclophosphamide (CP)-immunosuppressed mice for 5 or 15 days, it reversed the body and spleen weights, blood RBC and WBC levels, and splenocyte and bone marrow cells that were reduced by CP. Orally administered HY7712 increased concanavalin A-induced T cell proliferation to 84.5% of the normal group on day 15, although treatment with CP alone markedly reduced it to 53.7% of the normal group. Furthermore, orally administered HY7712 significantly induced the expressions of IL-2 and IFN-
in ConA-induced splenic cytotoxic T cells of CP-treated mice. Orally administered HY7712 restored the CP-impaired phagocytosis of macrophages in mice. Orally administered HY7712 also restored the cytotoxicity of NK and cytotoxic T cells derived from spleen and bone marrow against YAC-1 in CP-immunosuppressed mice. Based on these findings, orally administered HY7712 may accelerate the recovery of cyclophosphamide-caused immunosuppression, without evident side effects, by immunopotentiating NK and Tc cells, and may provide a mechanistic basis for using HY7712 as an alternative means in lessening chemotherapyinduced immunosuppression in cancer patients.
Characterization and Zoonotic Potential of Uropathogenic Escherichia coli Isolated from Dogs
Nam, Eui-Hwa ; Ko, Sungjin ; Chae, Joon-Seok ; Hwang, Cheol-Yong ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 422~429
DOI : 10.4014/jmb.1209.09051
The aim of this study was to investigate the characteristics of canine uropathogenic Escherichia coli (UPEC) and the interaction between canine UPEC and human bladder epithelial cells. Ten E. coli isolates collected from dogs with cystitis were analyzed for antimicrobial resistance patterns, the presence of virulence factors, and biofilm formation. The ability of these isolates to induce cytotoxicity, invade human bladder epithelial cells, and stimulate an immune response was also determined. We observed a high rate of antimicrobial resistance among canine UPEC isolates. All virulence genes tested (including adhesins, iron acquisition, and protectin), except toxin genes, were detected among the canine UPEC isolates. We found that all isolates showed varying degrees of biofilm formation (mean, 0.26; range, 0.07 to 0.82), using a microtiter plate assay to evaluate biofilm formation by the isolates. Cytotoxicity to human bladder epithelial cells by the canine UPEC isolates increased in a time-dependent manner, with a 56.9% and 36.1% reduction in cell viability compared with the control at 6 and 9 h of incubation, respectively. We found that most canine UPEC isolates were able to invade human bladder epithelial cells. The interaction between these isolates and human bladder epithelial cells strongly induced the production of proinflammatory cytokines such as IL-6 and IL-8. We demonstrated that canine UPEC isolates can interact with human bladder epithelial cells, although the detailed mechanisms remain unknown. The results suggest that canine UPEC isolates, rather than dogspecific pathogens, have zoonotic potential.
Gene Cloning and Characterization of MdeA, a Novel Multidrug Efflux Pump in Streptococcus mutans
Kim, Do Kyun ; Kim, Kyoung Hoon ; Cho, Eun Ji ; Joo, Seoung-Je ; Chung, Jung-Min ; Son, Byoung Yil ; Yum, Jong Hwa ; Kim, Young-Man ; Kwon, Hyun-Ju ; Kim, Byung-Woo ; Kim, Tae Hoon ; Lee, Eun-Woo ;
Journal of Microbiology and Biotechnology, volume 23, issue 3, 2013, Pages 430~435
DOI : 10.4014/jmb.1301.01028
Multidrug resistance, especially multidrug efflux mechanisms that extrude structurally unrelated cytotoxic compounds from the cell by multidrug transporters, is a serious problem and one of the main reasons for the failure of therapeutic treatment of infections by pathogenic microorganisms as well as of cancer cells. Streptococcus mutans is considered one of the primary causative agents of dental caries and periodontal disease, which comprise the most common oral diseases. A fragment of chromosomal DNA from S. mutans KCTC3065 was cloned using Escherichia coli KAM32 as host cells lacking major multidrug efflux pumps. Although E. coli KAM32 cells were very sensitive to many antimicrobial agents, the transformed cells harboring a recombinant plasmid became resistant to several structurally unrelated antimicrobial agents such as tetracycline, kanamycin, rhodamin 6G, ampicillin, acriflavine, ethidium bromide, and tetraphenylphosphonium chloride. This suggested that the cloned DNA fragment carries a gene encoding a multidrug efflux pump. Among 49 of the multidrug-resistant transformants, we report the functional gene cloning and characterization of the function of one multidrug efflux pump, namely MdeA from S. mutans, which was expressed in E. coli KAM32. Judging from the structural and biochemical properties, we concluded that MdeA is the first cloned and characterized multidrug efflux pump using the proton motive force as the energy for efflux drugs.