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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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The Korean Society for Applied Microbiology and Biotechnology
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Volume & Issues
Volume 22, Issue 12 - Dec 2012
Volume 22, Issue 11 - Nov 2012
Volume 22, Issue 10 - Oct 2012
Volume 22, Issue 9 - Sep 2012
Volume 22, Issue 8 - Aug 2012
Volume 22, Issue 7 - Jul 2012
Volume 22, Issue 6 - Jun 2012
Volume 22, Issue 5 - May 2012
Volume 22, Issue 4 - Apr 2012
Volume 22, Issue 3 - Mar 2012
Volume 22, Issue 2 - Feb 2012
Volume 22, Issue 1 - Jan 2012
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Cyanobacterial Diversity Shifts Induced by Butachlor in Selected Indian Rice Fields in Eastern Uttar Pradesh and Western Bihar Analyzed with PCR and DGGE
Kumari, Nidhi ; Narayan, Om Prakash ; Rai, Lal Chand ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 1~12
DOI : 10.4014/jmb.1106.06016
The present study examines the effects of 30 mg/kg butachlor on the cyanobacterial diversity of rice fields in Eastern Uttar Pradesh and Western Bihar in India. A total of 40 samples were grouped into three classes [(i) acidic, (ii) neutral, and (iii) alkaline soils], based on physicochemical and principle component analyses. Acidic soils mainly harbored Westillopsis, Trichormus, Anabaenopsis, and unicellular cyanobacteria; whereas Nostoc, Anabaena, Calothrix, Tolypothrix, and Aulosira were found in neutral and alkaline soils. Molecular characterization using 16S rRNA PCR and DGGE revealed the presence of 13 different phylotypes of cyanobacteria in these samples. Butachlor treatment of the soil samples led to the disappearance of 5 and the emergence of 2 additional phylotypes. A total of 40 DGGE bands showed significant reproducible changes upon treatment with butachlor. Phylogenetic analyses divided the phylotypes into five major clusters exhibiting interesting links with soil pH. Aulosira, Anabaena, Trichormus, and Anabaenopsis were sensitive to butachlor treatment, whereas uncultured cyanobacteria, a chroococcalean member, Westillopsis, Nostoc, Calothrix, Tolypothrix, Rivularia, Gloeotrichia, Fischerella, Leptolyngbya, and Cylindrospermum, appeared to be tolerant against butachlor at their native soil pH. Butachlor-induced inhibition of nitrogen fixation was found to be 65% (maximum) and 33% (minimum) in the soil samples of pH 9.23 and 5.20, respectively. In conclusion, low butachlor doses may prove beneficial in paddy fields having a neutral to alkaline soil pH.
Genotypic and Phenotypic Diversity of PGPR Fluorescent Pseudomonads Isolated from the Rhizosphere of Sugarcane (Saccharum officinarum L.)
Rameshkumar, Neelamegam ; Ayyadurai, Niraikulam ; Kayalvizhi, Nagarajan ; Gunasekaran, Paramsamy ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 13~24
DOI : 10.4014/jmb.1107.07025
The genetic diversity of plant growth-promoting rhizobacterial (PGPR) fluorescent pseudomonads associated with the sugarcane (Saccharum officinarum L.) rhizosphere was analyzed. Selected isolates were screened for plant growthpromoting properties including production of indole acetic acid, phosphate solubilization, denitrification ability, and production of antifungal metabolites. Furthermore, 16S rDNA sequence analysis was performed to identify and differentiate these isolates. Based on 16S rDNA sequence similarity, the isolates were designated as Pseudomonas plecoglossicida, P. fluorescens, P. libaniensis, and P. aeruginosa. Differentiation of isolates belonging to the same group was achieved through different genomic DNA fingerprinting techniques, including randomly amplified polymorphic DNA (RAPD), amplified ribosomal DNA restriction analysis (ARDRA), repetitive extragenic palindromic (REP), enterobacterial repetitive intergenic consensus (ERIC), and bacterial repetitive BOX elements (BOX) analyses. The genetic diversity observed among the isolates and rep-PCR-generated fingerprinting patterns revealed that PGPR fluorescent pseudomonads are associated with the rhizosphere of sugarcane and that P. plecoglossicida is a dominant species. The knowledge obtained herein regarding the genetic and functional diversity of fluorescent pseudomonads associated with the sugarcane rhizosphere is useful for understanding their ecological role and potential utilization in sustainable agriculture.
Virulence, Resistance Genes, and Transformation Amongst Environmental Isolates of Escherichia coli and Acinetobacter spp.
Doughari, Hamuel James ; Ndakidemi, Patrick Alois ; Human, Izanne Susan ; Benade, Spinney ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 25~33
DOI : 10.4014/jmb.1107.07029
The association of verotoxic E. coli and Acinetobacter spp. with various antibiotic-resistant, diarrhogenic, and nosocomial infections has been a cause for concern worldwide. E. coli and A. haemolyticus isolated on a number of selective media were screened for virulence factors, antibiotic resistance, and transformation of resistance genes. Out of 69 E. coli isolates obtained, 25 (35.23%), 14 (20.30%), and 28 (40.58%) were positive for Vtx1&2, Vtx1, and Vtx2, respectively, 49 (71.015%) for extendedspectrum beta-lactamases (ESBLs), 34 (49.28%) for serum resistance, 57 (82.61%) for cell surface hydrophobicity, 48 (69.57%) for gelatinase production, and 37 (53.62%) for hemolysin production. For the 14 A. haemolyticus isolates, only 2 (14.29%) in each case from all the samples investigated were positive for Vtx1, Vtx2 and Vtx1&2 respectively, 8 (57.14%) for ESBLs, 7 (50.00%) for serum resistance, 11 (78.57%) for cell surface hydrophobicity, 4 (28.57%) for gelatinase production, and 8 (57.14%) for hemolysin production. Although transformation occurred among the E. coli and Acinetobacter isolates (transformation frequency:
), there was poor curing of the plasmid genes, a confirmation of the presence of stable antibiotic-resistant genes (DNA concentration between 42.7 and 123.8
) and intragenetic transfer of multidrug-resistant genes among the isolates. The isolates were potentially virulent and contained potentially transferable antibiotic resistance genes. Detection of virulence factors, antibiotic resistance genes, and transformation among these isolates is a very significant outcome that will influence approaches to proactive preventive and control measures and future investigations. However, continued surveillance for drug resistance among these bacteria and further investigation of the mechanism of action of their virulence factors are a necessity.
Effect of Ion Pair on Thermostability of F1 Protease: Integration of Computational and Experimental Approaches
Rahman, Raja Noor Zaliha Raja Abd ; Noor, Noor Dina Muhd ; Ibrahim, Noor Azlina ; Salleh, Abu Bakar ; Basri, Mahiran ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 34~45
DOI : 10.4014/jmb.1105.05055
A thermophilic Bacillus stearothermophilus F1 produces an extremely thermostable serine protease. The F1 protease sequence was used to predict its three-dimensional (3D) structure to provide better insights into the relationship between the protein structure and biological function and to identify opportunities for protein engineering. The final model was evaluated to ensure its accuracy using three independent methods: Procheck, Verify3D, and Errat. The predicted 3D structure of F1 protease was compared with the crystal structure of serine proteases from mesophilic bacteria and archaea, and led to the identification of features that were related to protein stabilization. Higher thermostability correlated with an increased number of residues that were involved in ion pairs or networks of ion pairs. Therefore, the mutants W200R and D58S were designed using site-directed mutagenesis to investigate F1 protease stability. The effects of addition and disruption of ion pair networks on the activity and various stabilities of mutant F1 proteases were compared with those of the wild-type F1 protease.
Identification of the Fur-Binding Site in Regulatory Region of the Vulnibactin-Receptor Gene in Vibrio vulnificus
Lee, Hyun-Jung ; Lee, Kyu-Ho ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 46~49
DOI : 10.4014/jmb.1108.08042
The Vibrio vulnificus vuuA gene, of which expression is repressed by a complex of iron and ferric uptake regulator (Fur), was characterized to localize the Fur-binding site in its upstream regulatory region. In silico analysis suggested the presence of two possible Fur-binding sites; one is a classical Fur-box and the other is a previously reported distinct Fur-binding site. Site-directed mutagenesis and DNase I protection assays revealed the binding site for the iron-Fur complex, which includes an extended inverted repeat containing a homologous sequence to the classical Fur-box.
Cells Transformed by PLC-Gamma 1 Overexpression are Highly Sensitive to Clostridium difficile Toxin A-Induced Apoptosis and Mitotic Inhibition
Nam, Hyo-Jung ; Kang, Jin-Ku ; Chang, Jong-Soo ; Lee, Min-Soo ; Nam, Seung-Taek ; Jung, Hyun-Woo ; Kim, Sung-Kuk ; Ha, Eun-Mi ; Seok, Heon ; Son, Seung-Woo ; Park, Young-Joo ; Kim, Ho ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 50~57
DOI : 10.4014/jmb.1107.07018
) expression is associated with cellular transformation. Notably, PLC-
is up-regulated in colorectal cancer tissue and breast carcinoma. Because exotoxins released by Clostridium botulinum have been shown to induce apoptosis and promote growth arrest in various cancer cell lines, we examined here the potential of Clostridium difficile toxin A to selectively induce apoptosis in cells transformed by PLC-
overexpression. We found that PLC-
-transformed cells, but not vector-transformed (control) cells, were highly sensitive to C. difficile toxin A-induced apoptosis and mitotic inhibition. Moreover, expression of the proapoptotic Bcl2 family member, Bim, and activation of caspase-3 were significantly up-regulated by toxin A in PLC-
-transformed cells. Toxin A-induced cell rounding and paxillin dephosphorylation were also significantly higher in PLC-
-transformed cells than in control cells. These findings suggest that C. difficile toxin A may have potential as an anticancer agent against colorectal cancers and breast carcinomas in which PLC-
is highly up-regulated.
Purification and Characterization of a Novel Alkaline Protease from Bacillus horikoshii
Joo, Han-Seung ; Choi, Jang-Won ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 58~68
DOI : 10.4014/jmb.1109.09006
An investigation was conducted on the enhancement of production and purification of an oxidant and SDS-stable alkaline protease (BHAP) secreted by an alkalophilic Bacillus horikoshii, which was screened from the body fluid of a unique Korean polychaeta (Periserrula leucophryna) living in the tidal mud flats of Kwangwha Island in the Korean West Sea. A prominent effect on BHAP production was obtained by adding 2% maltose, 1% sodium citrate, 0.8% NaCl, and 0.6% sodium carbonate to the culturing medium. The optimal medium for BHAP production contained (g/l) SBM, 15; casein, 10;
, 2; maltose, 20; sodium citrate, 10;
, 0.06; NaCl, 8; and
, 6. A protease yield of approximately 56,000 U/ml was achieved using the optimized medium, which is an increase of approximately 5.5-fold compared with the previous optimization (10,050 U/ml). The BHAP was homogenously purified 34-fold with an overall recovery of 34% and a specific activity of 223,090 U/mg protein using adsorption with Diaion HPA75, hydrophobic interaction chromatography (HIC) on Phenyl-Sepharose, and ion-exchange chromatography on a DEAE- and CM-Sepharose column. The purified BHAP was determined a homogeneous by SDS-PAGE, with an apparent molecular mass of 28 kDa, and it showed extreme stability towards organic solvents, SDS, and oxidizing agents. The
values were 78.7
for N-succinyl-Ala-Ala-Pro-Phe-pNA at
and pH 9, respectively. The inhibition profile exhibited by PMSF suggested that the protease from B. horikoshii belongs to the family of serine proteases. The BHAP, which showed high stability against SDS and
, has significance for industrial application, such as additives in detergent and feed industries.
Metabolic Profiling and Biological Activities of Bioactive Compounds Produced by Pseudomonas sp. Strain ICTB-745 Isolated from Ladakh, India
Kama, Ahmed ; Shaik, Anver Basha ; Kumar, C. Ganesh ; Mongolla, Poornima ; Rani, P. Usha ; Krishna, K.V.S. Rama ; Mamidyala, Suman Kumar ; Joseph, Joveeta ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 69~79
DOI : 10.4014/jmb.1105.05008
In an ongoing survey of the bioactive potential of microorganisms from Ladakh, India, the culture medium of a bacterial strain of a new Pseudomonas sp., strain ICTB-745, isolated from an alkaline soil sample collected from Leh, Ladakh, India, was found to contain metabolites that exhibited broad-spectrum antimicrobial and biosurfactant activities. Bioactivity-guided purification resulted in the isolation of four bioactive compounds. Their chemical structures were elucidated by
NMR, 2D-NMR (HMBC, HSQC,
-COSY, and DEPT-135), FT-IR, and mass spectroscopic methods, and were identified as 1-hydroxyphenazine, phenazine-1-carboxylic acid (PCA), rhamnolipid-1 (RL-1), and rhamnolipid-2 (RL-2). These metabolites exhibited various biological activities like antimicrobial and efficient cytotoxic potencies against different human tumor cell lines such as HeLa, HepG2, A549, and MDA MB 231. RL-1 and RL-2 exhibited a dose-dependent antifeedant activity against Spodoptera litura, producing about 82.06% and 73.66% antifeedant activity, whereas PCA showed a moderate antifeedant activity (63.67%) at 60
area of castor leaf. Furthermore, PCA, RL-1, and RL-2 exhibited about 65%, 52%, and 47% mortality, respectively, against Rhyzopertha dominica at 20
. This is the first report of rhamnolipids as antifeedant metabolites against Spodoptera litura and as insecticidal metabolites against Rhyzopertha dominica. The metabolites from Pseudomonas sp. strain ICTB-745 have interesting potential for use as a biopesticide in pest control programs.
New Production of 5-Bromotoluhydroquinone and 4-O-Methyltoluhydroquinone from the Marine-Derived Fungus Dothideomycete sp.
Leutou, Alain S. ; Yun, Keum-Ja ; Choi, Hong-Dae ; Kang, Jung-Sook ; Son, Byeng-Wha ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 80~83
DOI : 10.4014/jmb.1108.08069
The addition of NaBr to the fermentation medium of a marine isolate of the fungus Dothideomycete sp. resulted in induced production of two toluhydroquinone derivatives, 5-bromotoluhydroquinone (1) and 4-O-methyltoluhydroquinone (2), and two known compounds, toluhydroquinone (3) and gentisyl alcohol (4). The structures of 1 and 2 were assigned through the spectroscopic data analyses. Compounds 1-4 showed a potent antibacterial activity against the methicillin-resistant and multidrug-resistant Staphylococcus aureus (MRSA and MDRSA) with MIC (minimum inhibitory concentration) values of 6.2, 12.5, 6.2, and 12.5
, respectively. Compounds 1-4 also exhibited a moderate radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) with
values of 11.0, 17.0, 12.0, and 7.0
, respectively, which were more active than the positive control, L-ascorbic acid (
Characterization of Lipases from Staphylococcus aureus and Staphylococcus epidermidis Isolated from Human Facial Sebaceous Skin
Xie, Winny ; Khosasih, Vivia ; Suwanto, Antonius ; Kim, Hyung-Kwoun ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 84~91
DOI : 10.4014/jmb.1107.07060
Two staphylococcal lipases were obtained from Staphylococcus epidermidis S2 and Staphylococcus aureus S11 isolated from sebaceous areas on the skin of the human face. The molecular mass of both enzymes was estimated to be 45 kDa by SDS-PAGE. S2 lipase displayed its highest activity in the hydrolysis of olive oil at
and pH 8, whereas S11 lipase showed optimal activity at
and pH 8.5. The S2 lipase showed the property of cold-adaptation, with activation energy of 6.52 kcal/mol. In contrast, S11 lipase's activation energy, at 21 kcal/mol, was more characteristic of mesophilic lipases. S2 lipase was stable up to
and within the pH range from 5 to 9, whereas S11 lipase was stable up to
and from pH 6 to 10. Both enzymes had high activity against tributyrin, waste soybean oil, and fish oil. Sequence analysis of the S2 lipase gene showed an open reading frame of 2,067 bp encoding a signal peptide (35 aa), a pro-peptide (267 aa), and a mature enzyme (386 aa); the S11 lipase gene, at 2,076 bp, also encoded a signal peptide (37 aa), pro-peptide (255 aa), and mature enzyme (399 aa). The two enzymes maintained amino acid sequence identity of 98-99% with other similar staphylococcal lipases. Their microbial origins and biochemical properties may make these staphylococcal lipases isolated from facial sebaceous skin suitable for use as catalysts in the cosmetic, medicinal, food, or detergent industries.
Poly(L-Lactide)-Degrading Enzyme Production by Actinomadura keratinilytica T16-1 in 3 L Airlift Bioreactor and Its Degradation Ability for Biological Recycle
Sukkhum, Sukhumaporn ; Tokuyama, Shinji ; Kitpreechavanich, Vichien ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 92~99
DOI : 10.4014/jmb.1105.05016
The optimal physical factors affecting enzyme production in an airlift fermenter have not been studied so far. Therefore, the physical parameters such as aeration rate, pH, and temperature affecting PLA-degrading enzyme production by Actinomadura keratinilytica strain T16-1 in a 3 l airlift fermenter were investigated. The response surface methodology (RSM) was used to optimize PLA-degrading enzyme production by implementing the central composite design. The optimal conditions for higher production of PLA-degrading enzyme were aeration rate of 0.43 vvm, pH of 6.85, and temperature at
. Under these conditions, the model predicted a PLA-degrading activity of 254 U/ml. Verification of the optimization showed that PLA-degrading enzyme production of 257 U/ml was observed after 3 days cultivation under the optimal conditions in a 3 l airlift fermenter. The production under the optimized condition in the airlift fermenter was higher than un-optimized condition by 1.7 folds and 12 folds with un-optimized medium or condition in shake flasks. This is the first report on the optimization of environmental conditions for improvement of PLA-degrading enzyme production in a 3 l airlift fermenter by using a statistical analysis method. Moreover, the crude PLA-degrading enzyme could be adsorbed to the substrate and degraded PLA powder to produce lactic acid as degradation products. Therefore, this incident indicates that PLA-degrading enzyme produced by Actinomadura keratinilytica NBRC 104111 strain T16-1 has a potential to degrade PLA to lactic acid as a monomer and can be used for the recycle of PLA polymer.
Metabolite Profiling and Bioactivity of Rice Koji Fermented by Aspergillus Strains
Kim, Ah-Jin ; Choi, Jung-Nam ; Kim, Ji-Young ; Kim, Hyang-Yeon ; Park, Sait-Byul ; Yeo, Soo-Hwan ; Choi, Ji-Ho ; Liu, Kwang-Hyeon ; Lee, Choong-Hwan ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 100~106
DOI : 10.4014/jmb.1106.06033
In this study, the metabolite profiles of three Aspergillus strains during rice koji fermentation were compared. In the partial least squares discriminant analysis-based gas chromatography-mass spectrometry data sets, the metabolite patterns of A. oryzae (KCCM 60345) were clearly distinguished from A. kawachii (KCCM 60552) and only marginal differences were observed for A. oryzae (KCCM 60551) fermentation. In the 2 days fermentation samples, the overall metabolite levels of A. oryzae (KCCM 60345) were similar to the A. oryzae (KCCM 60551) levels and lower than the A. kawachii (KCCM 60552) levels. In addition, we identified discriminators that were mainly contributing tyrosinase inhibition (kojic acid) and antioxidant activities (pyranonigrin A) in A. oryzae (KCCM 60345) and A. kawachii (KCCM 60552) inoculated rice koji, respectively. In this study, we demonstrated that the optimal inoculant Aspergillus strains and fermentation time for functional rice koji could be determined through a metabolomics approach with bioactivity correlations.
Development of a Practical and Cost-Effective Medium for Bioethanol Production from the Seaweed Hydrolysate in Surface-Aerated Fermentor by Repeated-Batch Operation
Lee, Sang-Eun ; Lee, Ji-Eun ; Shin, Ga-Young ; Choi, Woon-Yong ; Kang, Do-Hyung ; Lee, Hyeon-Yong ; Jung, Kyung-Hwan ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 107~113
DOI : 10.4014/jmb.1106.06019
To develop a practical and cost-effective medium for bioethanol production from the hydrolysate of seaweed Sargassum sagamianum, we investigated the feasibility and performance of bioethanol production in CSL (corn-steep liquor)-containing medium, where yeast Pichia stipitis was used and the repeated batch was carried out in a surface-aerated fermentor. The optimal medium replacement time during the repeated operation was determined to be 36 h, and the surface aeration rates were 30 and 100 ml/min. Under these conditions, the repeated-batch operation was successfully carried out for 6 runs (216 h), in which the maximum bioethanol concentrations reached about 11-12 g/l at each batch operation. These results demonstrated that bioethanol production could be carried out repeatedly and steadily for 216 h. In these experiments, the total cumulative bioethanol production was 57.9 g and 58.0 g when the surface aeration rates were 30 ml/min and 100 ml/min, respectively. In addition, the bioethanol yields were 0.43 (about 84% of theoretical value) and 0.44 (about 86% of theoretical value) when the surface aeration rates were 30 ml/min and 100 ml/min, respectively. CSL was successfully used as a medium ingredient for the bioethanol production from the hydrolysate of seaweed Sargassum sagamianum, indicating that this medium may be practical and cost-effective for bioethanol production.
Bacterial Mixture from Greenhouse Soil as a Biocontrol Agent Against Root-Knot Nematode, Meloidogyne incognita, on Oriental Melon
Seo, Byoung-Joo ; Kumar, V.J. Rejish ; Ahmad, Rather Irfan ; Kim, Byung-Chun ; Park, Wan ; Park, So-Deuk ; Kim, Se-Eun ; Kim, Sang-Dal ; Lim, Jeong-Heui ; Park, Yong-Ha ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 114~117
DOI : 10.4014/jmb.1105.05053
The biological control efficacy of a greenhouse soil bacterial mixture of Lactobacillus farraginis, Bacillus cereus, and Bacillus thuringiensis strains with antinematode activity was evaluated against the root-knot nematode Meloidogyne incognita. Two control groups planted in soil drenched with sterile distilled water or treated with the broad-spectrum carbamate pesticide carbofuran were used for comparison. The results suggest that the bacterial mixture is effective as a biocontrol agent against the root-knot nematode.
HspA and HtpG Enhance Thermotolerance in the Cyanobacterium, Microcystis aeruginosa NIES-298
Rhee, Jae-Sung ; Ki, Jang-Seu ; Kim, Bo-Mi ; Hwang, Soon-Jin ; Choi, Ik-Young ; Lee, Jae-Seong ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 118~125
DOI : 10.4014/jmb.1108.08001
Heat shock proteins (Hsps) play a key role in the cellular defense response to diverse environmental stresses. Here, the role of Hsp genes in the acquisition of thermotolerance in the cyanobacterium Microcystis aeruginosa NIES-298 was investigated. Twelve Hsp-related genes were examined to observe their modulated expression patterns at different temperatures (10, 15, 25, and
) over different exposure periods. HspA and HtpG transcripts showed an up-regulation of expression at low temperatures (10 and
) and high temperature (
), compared with the control (
). To examine their effects upon thermotolerance, we purified recombinant HspA and HtpG proteins. During a thermotolerance study at
, the HspA-transformed bacteria showed increased thermotolerance compared with the control. HtpG also played a role in the defense response to acute heat stress within 30 min. These findings provide a better understanding of cellular protection mechanisms against heat stress in cyanobacteria.
Survival and Performance of Two Cellulose-Degrading Microbial Systems Inoculated into Wheat Straw-Amended Soil
Li, Peipei ; Zhang, Dongdong ; Wang, Xiaojuan ; Wang, Xiaofen ; Cui, Zongjun ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 126~132
DOI : 10.4014/jmb.1102.02021
A cellulose-degrading composite microbial system containing a mixture of microbes was previously shown to demonstrate a high straw-degrading capacity. To estimate its potential utilization as an inoculant to accelerate straw biodegradation after returning straw to the field, two cellulose-degrading composite microbial systems named ADS3 and WSD5 were inoculated into wheat straw-amended soil in the laboratory. The microbial survival of the inoculant was confirmed by a denaturing gradient gel electrophoresis (DGGE) analysis, whereas the enhancement of straw degradation in soil was assessed by measuring the mineralization of the soil organic matter and the soil cellulase activity. The results indicated that most of the DGGE bands from ADS3 were detected after inoculation into straw-amended autoclaved soil, yet only certain bands from ADS3 and WSD5 were detected after inoculation into straw-amended non-autoclaved soil during five weeks of incubation; some bands were detected during the first two weeks after inoculation, and then disappeared in later stages. Organic matter mineralization was significantly higher in the soil inoculants ADS3 and WSD5 than in the uninoculated controls during the first week, yet the enhanced degradation did not persist during the subsequent incubation. Similar to the increase in soil organic matter, the cellulase activity also increased during the first week in the ADS3 and WSD5 treatments, yet decreased during the remainder of the incubation period. Thus, it was concluded that, although the survival and performance of the two inoculants did not persist in the soil, a significant enhancement of degradation was present during the early stage of incubation.
A Novel cry2Ab Gene from the Indigenous Isolate Bacillus thuringiensis subsp. kurstaki
Sevim, Ali ; Eryuzlu, Emine ; Demirbag, Zihni ; Demir, Ismail ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 133~140
DOI : 10.4014/jmb.1108.08061
A novel cry2Ab gene was cloned and sequenced from the indigenous isolate of Bacillus thuringiensis subsp. kurstaki. This gene was designated as cry2Ab25 and its sequence revealed an open reading frame of 1,902 bp encoding a 633 aa protein with calculated molecular mass of 70 kDa and pI value of 8.98. The amino acid sequence of the Cry2Ab25 protein was compared with previously known Cry2Ab toxins, and the phylogenetic relationships among them were determined. The deduced amino acid sequence of the Cry2Ab25 protein showed 99% homology to the known Cry2Ab proteins, except for Cry2Ab10 and Cry2Ab12 with 97% homology, and a variation in one amino acid residue in comparison with all known Cry2Ab proteins. The cry2Ab25 gene was expressed in Escherichia coli BL21(DE3) cells. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed that the Cry2Ab25 protein is about 70 kDa. The toxin expressed in BL21(DE3) exhibited high toxicity against Malacosoma neustria and Rhagoletis cerasi with 73% and 75% mortality after 5 days of treatment, respectively.
Functional Expression and Characterization of Recombinant NADPH-P450 Reductase from Malassezia globosa
Lee, Hwa-Youn ; Park, Hyoung-Goo ; Lim, Young-Ran ; Lee, Im-Soon ; Kim, Beom-Joon ; Seong, Cheul-Hun ; Chun, Young-Jin ; Kim, Dong-Hak ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 141~146
DOI : 10.4014/jmb.1107.07058
Malassezia globosa is a common pathogenic fungus that causes skin diseases including dandruff and seborrheic dermatitis in humans. Analysis of its genome identified a gene (MGL_1677) coding for a putative NADPH-P450 reductase (NPR) to support the fungal cytochrome P450 enzymes. The heterologously expressed recombinant M. globosa NPR protein was purified, and its functional features were characterized. The purified protein generated a single band on SDS-PAGE at 80.74 kDa and had an absorption maximum at 452 nm, indicating its possible function as an oxidized flavin cofactor. It evidenced NADPH-dependent reducing activity for cytochrome c or nitroblue tetrazolium. Human P450 1A2 and 2A6 were able to successfully catalyze the O-deethylation of 7-ethoxyresorufin and the 7-hydroxylation of coumarin, respectively, with the support of the purified NPR. These results demonstrate that purified NPR is an orthologous reductase protein that supports cytochrome P450 enzymes in M. globosa.
Synergic Effects of Bitter Melon and
-Glucan Composition on STZ-Induced Rat Diabetes and Its Complications
Kim, Joo-Wan ; Cho, Hyung-Rae ; Moon, Seung-Bae ; Kim, Ki-Young ; Ku, Sae-Kwang ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 147~155
DOI : 10.4014/jmb.1106.06037
-Glucan purified from oats (OG) and bitter melon, Momordica charantia Linn (MC), water extracts have shown favorable effects on diabetes and its complications. We investigated to find out the optimal composition showing hypoglycemic and antidiabetic complication effects in variable compositions (OG:MC = 1:1, 1:2, 1:4, 1:6, 1:8, 1:10, 2:1, 4:1, 6:1, 8:1, 10:1). Extracts were administered orally once a day for 28 days following 7 days post streptozotocin (STZ) dosing. Five rats per group (total 15 groups; Intact, STZ, OG, MC, and the variable composition groups) were selected according to the blood glucose and body weight at 6 days after STZ dosing. After 28 days of extracts dosing, the changes on the body weight, liver and kidney weight, blood glucose, blood urea nitrogen (BUN), creatinine, aspartate aminotransferase (AST) and alanine aminotransferase (ALT), low-density lipoprotein (LDL), and total-cholesterol levels were observed. As the result of STZ-induced diabetes, decreases of body weight, increases of the liver and kidney weights, blood glucose, BUN, creatinine, AST, ALT, LDL, and total-cholesterol levels in STZ control were detected compared with intact control. However, these changes of hyperglycemia, diabetic nephropathy, hepatopathy, and hyperlipemia were dramatically decreased in the OG and MC single-dosing group, and all composition groups. In addition, there were more favorable effects in all composition groups compared with the OG and MC single-dosing groups. Among variable compositions, the OG:MC 1:2 mixed group showed the most synergic effects in this study.
Effects of the Synthetic Coprisin Analog Peptide, CopA3 in Pathogenic Microorganisms and Mammalian Cancer Cells
Kim, In-Woo ; Kim, Soon-Ja ; Kwon, Yong-Nam ; Yun, Eun-Young ; Ahn, Mi-Young ; Kang, Dong-Chul ; Hwang, Jae-Sam ;
Journal of Microbiology and Biotechnology, volume 22, issue 1, 2012, Pages 156~158
DOI : 10.4014/jmb.1109.09014
A synthetic coprisin analog peptide, 9-mer dimer CopA3 (CopA3) was designed based on a defensin-like peptide, Coprisin, isolated from the bacteria-immunized dung beetle Copris tripartitus. Here, CopA3 was investigated for its antimicrobial activity and cancer cell growth inhibition. CopA3 showed antimicrobial activities against various pathogenic bacteria and yeast fungus with MIC values in 2~32
ranges, and inhibited the cell viabilities of pancreatic and hepatocellular cancer cells, except MIA-Paca2, Hep3B, and HepG2 cells, in a dose-dependent manner. The average
values of CopA3 against pancreatic and hepatocellular cancer cells were 61.7
, respectively. The results indicate that CopA3 has potential in the treatments of pancreatic and hepatocellular cancers as well as microorganism infection disease.