Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Journal of Microbiology and Biotechnology
Journal Basic Information
Journal DOI :
The Korean Society for Applied Microbiology and Biotechnology
Editor in Chief :
Volume & Issues
Volume 13, Issue 6 - Dec 2003
Volume 13, Issue 5 - Oct 2003
Volume 13, Issue 4 - Aug 2003
Volume 13, Issue 3 - Jun 2003
Volume 13, Issue 2 - Apr 2003
Volume 13, Issue 1 - Feb 2003
Selecting the target year
Biogeochemical Activities of Microorganisms in Mineral Transformations: Consequences for Metal and Nutrient Mobility
Gadd, Geoffrey-M. ; Burford, Euan-P. ; Fomina, Marina ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 323~331
Bacteria and fungi are fundamental biotic components of natural biogeochemical cycles for metals and metalloids, and play important roles in dissolution, precipitation, oxidation and reduction processes. Some processes catalyzed by microorganisms also have important applications in environmental biotechnology in the areas of ore leaching and bioremediation.
Analysis of Kinetic Data of Pectinases with Substrate Inhibition
Gummadi, Sathyanarayana-N. ; Panda, T. ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 332~337
Enzyme kinetics data play a vital role in the design of reactors and control of processes. In the present study, kinetic studies on pectinases were carried out. Partially purified polymethylgalacturonase (PMG) and polygalacturonase (PG) were the two pectinases studied. The plot of initial rate vs. initial substrate concentration did not follow the conventional Michaelis-Menten kinetics, but substrate inhibition was observed. For PMG, maximum rate was attained at an initial pectin concentration of 3 g/l, whereas maximum rate was attained when the initial substrate concentration of 2.5 g/l of polygalacturonic acid for PG I and PG II. The kinetic data were fitted to five different kinetic models to explain the substrate inhibition effect. Among the five models tested, the combined mechanism of protective diffusion limitation of both high and inhibitory substrate concentrations (semi-empirical model) explained the inhibition data with 96-99% confidence interval.
Quadrivalent Combined Vaccine, Including Diphtheria Toxoid, Tetanus Toxoid, Detoxified Whole Cell Pertussis, and Hepatitis B Surface Antigen
Bae, Cheon-Soon ; Lim, Gwan-Yeul ; Kim, Jong-Su ; Hur, Byung-Ki ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 338~343
Various factors, such as the adsorption pH, adjuvant dose, and adjuvant age, which affect the adsorption degree and immunogenicity of an antigen, were investigated. In addition, the effect of pH, antigen content, and adjuvant content on immunogenicity was also studied through animal experiments. Within the ranges studied, a low pH for adsorption, freshly preformed gel, and low pH formulation for the combined DTwP-HepB vaccine were preferrable for the adsorption of the antigens. In addition, a higher DT content was found to have a positive effect on the HBsAg immunogenicity in the combined vaccine. Accordingly, considering the factors affecting the adsorption rate and immunogenicity of the antigens, a novel DTwP-HepB vaccine (40 Lf/ml of diphtheria toxoid, 15 Lf/ml of tetanus toxoid, 20 OU/ml of detoxified whole cell pertussis,
, and pH 7.1) was developed, whose immunogenicity was comparable to the case of administrating, separately and simultaneously, a combined DTwP vaccine (40 Lf/ml of diphtheria toxoid, 15 Lf/ml of tetanus toxoid, 20 OU/ml of detoxified whole cell pertussis,
, and pH 7.1) and mono HepB vaccine [
of HBsAg and
], which satisfies the potency criteria of the K-FDA for a combined DTwP vaccine and mono HepB vaccine.
Optimization of Programmed Suppression in a Cell-Free Protein Synthesis System with Unnatural Amino Acid S-(2-Nitrobenzyl)cysteine
HYUN JOO ; KANG, TAEK JIN ; HUI KYOUNG SONG ; JIN HO AHN ; CHA YONG CHOI ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 344~347
Unnatural amino acid S-(2-nitrobenzyl)cysteine was incorporated into human erythropoietin by using a programmed suppression of nonsense codon in a cell-free protein synthesis system. Several controlling factors affecting the operational efficiency of the suppression were investigated and optimized. The amount of suppressor tRNA and the concentration of
were crucial not only for the efficiency but also for the control of the exact suppression. In addition, some general optimization factor are reported in order to improve the efficiency in an unnatural amino acid mutagenesis.
Prebiotic Properties of Levan in Rats
Jang, Ki-Hyo ; Kang, Soon-Ah ; Cho, Yun-Hi ; Kim, Yun-Young ; Lee, Yun-Jung ; Hong, Kyung-Hee ; Seong, Kyung-Hwa ; Kim, So-Hye ; Kim, Chul-Ho ; Rhee, Sang-Ki ; Ha, Sang-Do ; Choue, Ryo-Won ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 348~353
Generally, two different types of fructose polymer are found in nature. One is inulin, whose fructosyl residues are linked mainly by a
, while the other is high-molecular-weight levan, whose fructosyl residues are linked mainly by a
. In contrast to the extensive studies on the prebiotic properties of inulin, there has been no report on the effect of levan on the large bowel microflora in viva. Therefore, to examine whether dietary levan can be used as a prebiotic, Sprague-Dawley male rats were fed one of two diets for 3 weeks: 1) basal diet plus sucrose; 2) basal diet plus 10% (wt/wt) levan. The cecal bowel mass, cecal and colon short-chain fatty acids (SCFAs), pH, and microflora were then compared. The intake of the levan-containing diet significantly increased the total cecal weight and wall weight. The analyses of the SCFAs in the cecal and colonic contents revealed that levan was converted into acetate, butyrate, and lactate, which resulted in acidic conditions. The intake of levan also significantly increased the total number of microorganisms by 5-fold and lactic acid-producing bacteria (LAB) 30-fold in the feces. Accordingly, the current work shows that levan can be used as a prebiotic for stimulating the growth of LAB in an animal model.
Detection of MecA Gene in Clinical Isolates of Staphylococcus aureus by Multiplex-PCR, and Antimicrobial Susceptibility of MRSA
Lee, Hyean-Woo ; Yoon, Joon-Ho ; Sohn, Joon-Hyung ; Lee, Kyoung-Ho ; Yeh, Byung-Il ; Park, Deok-Woo ; Kim, Hyun-Won ; Choi, Jong-Whan ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 354~359
Multiplex-PCR protocols were designed in order to make a rapid identification of MRSA. MecA, femB, and 165 rRNA genes were amplified for making a detection of MRSA. The incidence of MRSA in the clinical isolates of Staphylococcus aureus was examined by using a multiplex-PCR assay. The mecA gene was detected in 266 strains out of 336 clinical isolates of S. aureus, thus the incidence of MRSA was approximately 76.5%. The MRSAs of 247 strains (96.1%) showed resistance to more than eight species of the antimicrobial agents tested. The isolates of MRSA showed 27 different antimicrobial-resistant patterns. The results indicate that many different MRSA strains having high multidrug resistance are actually prevalent in Korea. Also, VISA was screened from the MRSA. Two strains were grown on the BHI agar plate supplemented with
of vancomycin at a frequency of
colony forming units or higher.
Conversion of Unsaturated Food Fatty Acids into Hydroxy Fatty Acids by Lactic Acid Bacteria
Kim, Myung-Hee ; Park, Mee-Seung ; Chung, Chang-Ho ; Kim, Cheong-Tae ; Kim, Youn-Soon ; Kyung, Kyu-Hang ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 360~365
The ability of 19 lactic acid bacteria to produce hydroxy fatty acids (HFAs) from unsaturated food fatty acids (USFAs) was tested. HFAs are related to human ailments, including steatorrhea. All the cultures produced HFAs from USFAs, unless their growth was inhibited by free USFAs. Lactococcus lactis subsp. lactis KFRI 131 converted oleic, linoleic, and linolenic acid into 10-hydroxyoctadecanoic acid (10-HODA), 10-hydroxyoctadecaenoic acid (10-HODEA), and 10-hydroxyoctadecadienoic acid (10-HODDEA), respectively. Both a USFA and a surfactant were needed for the bacterium to convert the fatty acid into the corresponding HFA. It was apparent that the production of 10-HODA was growth-related, while that of 10-HODDEA was not. It was unclear whether the production of 10-HODEA was growth-related.
Anaerobic Degradation of cis-1,2-Dichloroethylene by Cultures Enriched from a Landfill Leachate Sediment
Chang, Young-Cheol ; Jung, KwEon ; Yoo, Young-Sik ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 366~372
The production of microbiologically enriched cultures that degrade cis- 1,2-dichloroethylene(DCE) under anaerobic conditions was investigated. Among 80 environmental samples, 19 displayed significant degradation of
cis-DCE during 1 month of anaerobic incubation, and one sediment sample collected at a landfill area (Nanji-do, Seoul, Korea) showed the greatest degradation (
). When this sediment culture was subcultured repeatedly, the ability to degrade cis-DCE gradually decreased. However, under Fe(III)-reducing conditions, cis-DCE degradation by the subculture was found to be maintained effectively. In the Fe(III)-reducing subculture, vinyl chloride (VC) was also degraded at the same extent as cis-DCE No accumulation of VC during the cis-DCE degradation was observed. Thus, Fe(III)-reducing microbes might be involved in the anaerobic degradation of the chlorinated ethenes. However, the subcultures established with Fe(III) could function even in the absence of Fe(III), showing that the degradation of cis-DCE and VC was not directly coupled with the Fe(III) reduction. Consequently, the two series of enrichment cultures could not be obtained that degrade both cis-DCE and VC in the presence or absence of Fe(III). Considering the lack of VC accumulation, both cultures reported herein may involve interesting mechanism(s) for the microbial remediation of environments contaminated with chlorinated ethenes. A number of fermentative reducers (microbes) which are known to reduce Fe(III) during their anaerobic growth are potential candidates involved in cir-DCE degradation in the presence and absence of Fe(III).
Ion-Sensitive Field Effect Transistor-Based Multienzyme Sensor for Alternative Detection of Mercury ions, Cyanide, and Pesticide
Vyacheslav, Volotovskky ; Kim, Nam-Soo ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 373~377
Various groups of industrial and agricultural pollutants (heavy metal ions, cyanides, and pesticides) can be detected by enzymes. Since heavy metal ions inhibit urease, cyanides inhibit peroxidase, organophosphorus and carbamate pesticides inhibit butyrylcholinesterase, these enzymes were co-immobilized into a bovine serum albumin gel on the surface of an ion-sensitive field effect transistor to create a bioprobe that is sensitive to the compounds mentioned above. The sensitivity of the present sensor towards KCN corresponded to
with 1 min of incubation time. The detection limits for Hg(II) ions and the pesticide carbofuran were 0.1 and
, respectively, when a 10 min sensor incubation time in contaminated samples was chosen. The total time for determining the concentrations of all species mentioned did not exceed 20 min.
Microbial and Physicochemical Monitoring of Granular Sludge During Start-up of Thermophilic UASB Reactor
Ahn, Yeong-Hee ; Park, Sung-Hoon ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 378~384
Mesophilically-grown granular sludge seeded in thermophilic UASB reactor was monitored to better understand the start-up process of the reactor. The reactor was fed with a synthetic wastewater containing glucose. As COD loading rate increased stepwise, methane production rate increased. Maximum values of COD removal efficiency (95%) and methane production rate (5.3 l/day) were achieved by approximately day-80 and remained constant afterward. However, physicochemical and microbial properties of granules kept changing even after day-80. Specific methanogenic activity (SMA) was initially negligible, and increased continuously until day-153 and remained constant afterward, showing the maximum value of
VSS/day. Deteriorated settling ability of granules recovered the initial value by day-98 and was maintained afterward, as determined by sludge volume index. Initially reduced granule size increased until day-126, reaching a plateau of 1.1 mm. Combined use of fluorescence in situ hybridization and confocal laser scanning microscopy (CLSM) allowed to localize families of Methanosaetaceae and Merhanosarcinaceae in granules with time Quantitative analyses of CLSM images of granule sections showed abundance patterns of the methanogens and numerical dominance of Methanosaeta spp. throughout the start-up period. The trend of SMA agreed well with abundance patterns of the methanogens.
Microbial Communities of Activated Sludge Performing Enhanced Biological Phosphorus Removal in a Sequencing Batch Reactor Supplied with Glucose
Jeon, Che-Ok ; Seung, Han-Woo ; Park, Jong-Moon ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 385~393
Microbial communities were analyzed in an anaerobic/aerobic sequencing batch reactor (SBR) fed with glucose as a sole carbon source. Scanning electron microscopy (SEM) showed that tetrad or cuboidal packet bacteria dominated the microbial sludge. Quinone, slot hybridization, and 165 rRNA gene sequencing analyses showed that the Proteobacteria beta subclass and the Actinobacteria group were the main microbial species in the SBR sludge. However, according to transmission electron microscopy (TEM), the packet bacteria did not contain polyphosphate granules or glycogen inclusions, but only separate coccus-shaped bacteria contained these, suggesting that coccus-shaped bacteria accumulated polyphosphate directly and the packet bacteria played other role in the enhanced biological phosphorus removal (EBPR). Based on previous reports, the Actinobacteria group and the Proteobacteria beta subclass were very likely responsible for acid formation and polyphosphate accumulation, respectively, and their cooperation achieved the EBPR in the SBR operation which was supplied with glucose.
Growth Inhibition and Apoptosis Induction of Gastric Cancer Cells by Copper (II) Glycinate Complex
JE CHUL LEE ; JEONG, YONG WOOK ; KISUNG KIM ; JAE YOUNG OH ; JONG CHUN PARK ; JUNG HWAN BANG ; ANG WON CHOI ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 394~399
The in vitro cytotoxic effects of newly synthesized copper (II) glycinate complex were investigated in two gastric cancer cell lines of SNU484 and SNU638 cells. The complex inhibited the growth and decreased the viability of both gastric cancer cells in a dose-dependent manner. Gastric cancer tells treated with the complex exhibited the features of apoptosis, as demonstrated by fragmentation of chromosomal DNA, activation of caspase-3-like enzyme, and cleavage of poly［ADP-ribose］ polymerase (PARP). With the treatment of copper (II) glycinate complex, the active form of caspase-3 was observed in SNU484 cells, but not in SNU638 cells, indicating that an alternative pathway of apoptosis might have been triggered in SNU638 cells. In conclusion, copper (II) glycinate complex induces apoptosis of SNU484 and SNU638 gastric cancer cells, and it is suggested that novel copper (II) glycinate complex is highly active against human gastric cancer cells.
HpkA, a Histidine Protein Kinase Homolog, is Required for Fruiting Body Development in Myxococcus xanthus
Park, Soo-Yeon ; Kim, Ji-Hoon ; Lee, Bng-soo ; Zusman, David-R ; Cho, Kyungyun ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 400~405
A gene (hpkA), encoding a histidine protein kinase homolog, has been identified in the upstream region of the espAB operon in Myxococcus xanthus. It encodes a 333 amino acid (35,952 Da) protein with a histidine protein kinase domain in the region from amino acid 90 to 317. Null mutations in the hpkA gene caused formation of loose irregular fruiting bodies, while wild-type strains developed tight hemispherical fruiting bodies under developmental conditions. Sporulation of the hpkA mutant was delayed by at least 12 h compared to that of the wild-type. It appeared that the hpkA mutation increased the expression of the espAB operon by more than 2-fold compared with the wild-type under developmental conditions. Expression of the hpkA gene was low under vegetative conditions, but was highly induced under developmental conditions.
Phylogenetic Evaluation of Stereoid Fungi
Yoon, Sung-Il ; Kim, Seon-Young ; Lim, Young-Woon ; Jung, Hack-Sung ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 406~414
Phylogenetic relationships of stereoid fungi were examined by comparing nuclear small subunit ribosomal RNA gene sequences. Stereoid taxa were scattered into several groups and the traditional Stereaceae proved to be polyphyletic. Srereum and Xylobolus were classified in the Stereaceae as the core group of stereoid fungi, and Amylostereum was grouped with Echinodontium of the Echinodontiaceae. Chondrostereum and Cystosrereum were clustered in the Stereaceae sensu Donk and Cymatoderma and Podoscypha in the Podoscyphaceae Reid. Columnocystis abietinum and C. ambigua were grouped with Meripilus giganteus and proved to be not included in the Chaetodermataceae sensu Nakasone. Lopharia cinerascens and L. mirabilis were grouped together but L. spadicea was unrelated to them, indicating that Lopharia is heterogeneous at a generic level.
of Pseudomonas fluorescens 2112 Inhibits Phytophthora capsici, a Red-Pepper Blight-Causing Fungus
Kim, Sang-Dal ; Lee, Eun-Tag ; Lim, Si-Kyu ; Nam, Doo-Hyun ; Khang, Yong-Ho ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 415~421
A bacterium, Pseudomonas fluorescens 2112, that is antagonistic against a red-pepper blight-causing fungus, Phytophthora capsici, was isolated from the local soil of Gyongju, Korea. This strain formed an orange-colored clear halo zone on chrome azurol S (CAS) blue agar, suggesting the production of a siderophore in addition to an antifungal antibiotic. The optimal culture conditions for siderophore production by P. fluorescens 2112 were 30-h cultivation at
and pH 6.5 in King's B medium. The presence of
ion or EDDHA promoted the production of siderophore in King's B medium. The siderophore was purified from culture broth by CM-Sephadex C-25 and Sephadex G-25 column chromatographies. The UV spectra of the purified siderophore was the same as that of pyoverdins or pseudobactins. The molecular mass was 1,958 Da determined by FAB-rlass spectrometer, and the amino acid composition analysis showed that the purified siderophore consisted of glycine/threonine/serine/glutamic acid/alanine/lysine with the molar ratio of 3:2:1:1:1:1, DL-Threo-
-hydroxyaspartic acid and
-hydroxyornithine, two of the essential constituents of pyoverdin, were also found. The purified siderophore pyoverdin showed strong in vitro and in vivo antagonistic activities against phytophthora blight-causing P. capsici. Especially in an in vivo pot test, the siderophore protected red-pepper Capsicum annum L. very well from the attack of P. capsici. These results indicated that the purified siderophore of P. fluorescens 2112 played a critical role in the biocontrol of the red-pepper blight disease, equivalent to treatment by P.fluorescens 2112 cells.
Proliferation, Apoptosis, and Telomerase Activity in Human Cord Blood CD34+ Cells Cultured with Combinations of Various Cytokines
Ahn, Myung-Ju ; Lee, Hye-Sook ; Jang, Mi-Yune ; Choi, Jung-Hye ; Lee, Young-Yeul ; Park, Hyung-Bae ; Lee, Yong-Sung ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 422~428
Umbilical cord blood (UCB), a rich source of hematopoietic stem/progenitor cells, has been proposed as an alternative to bone marrow and peripheral blood for transplantation treatment. Ex vivo expansion of cord blood stem cells could make the use of cord blood transplant feasible even for adult patients. However, the optimal cytokine cocktail for expansion of stem cells is yet to be established. This study compares proliferation, apoptosis, and telomerase activities in human cord blood stem cells cultured ex vivo with FLT3 ligand (FL)/thrombopoietin (TPO) or FL/TPO/stem cell factor (SCF), with a view to determine optimal combination of cytokines. CD34+ cells were cultured in DMEM containing either FL (50 ng/ml) and TPO (10 ng/ml) (FT group) or FL (50 ng/ml), TPO (10 ng/ml) and SCF (50 ng/ml) (FTS group). The cell proliferation rate was ten times higher in the FTS group. Although cells cultured with the two different combinations of cytokines were maintained for a long term (up to 8 weeks), a large number of cells underwent differentiation during this period. Cells cultured in FTS displayed lower levels of apoptosis compared to those of the FT group during the Initial 7 days of culture. The CD34+ fraction in both groups was markedly decreased to
, and only
was detected at 14 days of culture. Telomerase activity detected in human CD34+ cord blood at low levels was upregulated during the early phase of culture and decreased to baseline levels in the later phase. The telomerase activity of cord blood cultured in FT was lower than that of the FTS group. Our results suggest that, on adding stem cell factors to the FT cytokines, cultured CD34+ cord blood cells display a greater degree of cell proliferation and decreased apoptosis. However, during CD34+ cord blood cell culture, a Barge number of cells undergo differentiation, indicating that more potent novel cytokines or new culture conditioning methods should be developed to maintain their ability to engraft and sustain long-term hematopoiesis.
Antibiosis of Pediocin-Producing Pediococcus sp. KCA1303-10 Against Listeria monocytogenes in Mixed Cultures
Ahn, Cheol ; Kim, Chung-Hoi ; Shin, Hyun-Kyung ; Lee, Young-Min ; Lee, Yeon-Sook ; Ji, Geun-Eog ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 429~436
Pediocin K1 is a bacteriocin produced by Pediococcus sp. KCA 1303-10, isolated from traditionally fermented flatfish in Korea. Pediocin K1-dependent antibiosis and pediocin K1-independent antibiosis against Listeria monocyrogenes were investigated by comparing antibiosis potential of the ped＋ wild-type strain of Pediococcus sp. KCA1303-10 with that of the ped- mutant strain in 3 different media at 3 different temperatures. In the synthetic MRS-APT medium, bacteriocin (pediocin K1)-dependent antibiosis (BDA) acted as the major driving force of overall antibiosis at the initial stage before the pH of the media was not sufficiently lowered, while bacteriocin-independent antibiosis (BIA) took over the major role at the late stage of antibiosis by killing otherwise resistant cells in the modium. The role of BDA increased as the temperature of the system decreased. The antibiosis potential of BDA among the overall antibiosis of Pediococcus against Listeria at
was calculated as 46%, and as 75% at
. In the skim milk medium, antibiosis of Pediococcus against Listeria was weakened more than 4 log cycles compared to that of the synthetic medium; however, BDA worked as the main antibiosis force regardless of the culturing temperature in the skim milk medium. In the bean soup medium, BDA also worked as the major killing mechanism against Listeria, but BIA played as another suppressing mechanism against otherwise pediocin-resistant Listeria population. These results suggest that a large portion of the inhibitory action of the ped+Pediococcus sp. KCA1303-10 was attributable to the bacteriocin produced by the strain and that viable Pediococcus sp. KCA1303-10 was superior to the purified bacteriocin in suppressing the occurrence of the bacteriocin-resistant Listeria monocytogenes in food systems.
Effectiveness of Bioremediation on Oil-Contaminated Sand in Intertidal Zone
Oh, Young-Sook ; Sim, Doo-Suep ; Kim, Sang-Jin ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 437~443
Bioremediation technologies were applied to experimental microcosms, simulating an oil spill in a lower intertidal area. Three treatments (oil only, oil plus nutrients, and oil plus nutrients and microbial inocula) were applied, and each microcosm was repeatedly filled and eluted with seawater every 12 h to simulate tidal cycles. To minimize washing-out of the inoculum by the tidal cycles, microbial cells were primarily immobilized on diatomaceous earth before they were applied to the oiled sand. Oil degradation was monitored by gravimetric measurements, thin layer chromatography/flame ionization detector (TLC/FID) analysis, and gas chromatography (GC) analysis, and the loss of oil content was normalized to sand mass or nor-hopane. When the data were normalized to sand mass, no consistent differences were detected between nutrient-amended and nutrient/inoculum-amended microcosms, although both differed from the oil-only microcosm in respect of oil removal rate by a factor of 4 to 14. However, the data relative to nor-hopane showed a significant treatment difference between the nutrient-amended and nutrient/inoculum-treated microcosms, especially in the early phase of the treatment. The accelerating effect of inoculum treatment has hardly been reported in studies of oil bioremediation in the Tower intertidal area. The inoculum immobilized on diatomaceous earth seemed to be a very effective formulation for retaining microbial cells in association with the sand. Results of this study also suggest that interpretation of the effectiveness of bioremediation could be dependent on the selection of monitoring methods, and consequently the application of various analytical methods in combination could be a solution to overcome the limitations of oil bioremediation monitoring.
Protection of Rabbits from Experimental Pseudomonas Endophthalmitis by Human Anti-P. aeruginosa Outer Membrane Proteins IgG
Lee, Na-Gyong ; Ahn, Bo-Young ; Kwon, Oh-Woong ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 444~450
In order to develop an effective means to treat P. aeruginosa infections, we have purified P. aeruginosa outer membrane proteins (OMPs)-specific human IgG antibody. In this study, we investigated the protective activity of the purified anti-OMPs IgC against P. aeruginosa infection in a rabbit endophthalmitis model. Rabbits were inoculated by an intravitreal injection with P. aeruginosa, and treated with a single dose of 1 mg anti-P. aeruginosa OMPs IgG. All the control rabbits predominantly developed edematous responses and opacity in the eyes, but the rabbits treated with the antibody showed only very limited degree of edema. Aliquots of the vitreous humor were extracted and analyzed for the number of viable bacteria and endotoxin level. The results showed that the anti-OMPs IgC significantly reduced the bacterial count compared with the control group, and that the endotoxin level of the vitreous from the IgG-treated rabbits was more than 70-fold lower 6 h after the administration than the control animals. These data suggested that the anti-P. aeruginosa OMPs IgG is effective in inhibiting the bacterial growth and thereby in reducing endotoxin levels in the vitreous, warranting further development of the anti-P. aeruginosa OMPs IgG as a therapeutic means for treating Pseudomonas endophthalmitis.
Overexpression of Thermoalkalophilic Lipase from Bacillus stearothermophilus L1 in Saccharomyces cerevisiae
Ahn, Jung-Oh ; Jang, Hyung-Wook ; Lee, Hong-Weon ; Choi, Eui-Sung ; Haam, Seung-Joo ; Oh, Tae-Kwang ; Jung, Joon-Ki ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 451~456
An expression vector system was developed for the secretory production of recombinant Bacillus stearothermophilus L1 lipase in Saccharomyces cerevisiae. The mature L1 lipase gene was fused to
signal sequence from Aspergillus oryzae for the effective secretion into the culture broth and the expression was controlled under GAL10 (the gene coding UDP-galactose epimerase of S. cerevisiae) promoter. S. cerevisiae harboring the resulting plasmid successfully secreted L1 lipase into the culture broth. To examine an optimum condition for L1 lipase expression in the fed-batch culture, L1 lipase expression was induced at three different growth phases (early, mid, and late-exponential growth phases). Maximum product on of L1 lipase (1,254,000 U/l, corresponding to 0.65/1) was found when the culture was induced at an early growth phase. Secreted recombinant L1 lipase was purified only through CM-Sepharose chromatography, and the purified enzyme showed 1,963 U/mg of specific activity and thermoalkalophilic properties similar to those reported for the enzyme expressed in Escherichia coli.
Molecular Characterization of Plasmid from Bifidobacterium longum
Park, Myeong-Soo ; Moon, Hye-Won ; Ji, Geun-Eog ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 457~462
The complete nucleotide sequence of a plasmid, pMG1, isolated from Bifidobacterium longum MG1 has been determined. This plasmid, composed of 3,862 base pairs with 65.1% of G+C content. harbors two major open reading frames (ORF) encoding putative proteins of 29 kDa (ORF I) and 71 kDa (ORF II). ORF I showed relatively high amino acid sequence homology with replication proteins of other plasmids from Gr Im-positive and -negative bacteria. Upstream of ORF I, four sets of tandem repeat sequences resembling the iteron structure of related plasmids were found. S1 endonuclease treatment and Southern blot analysis revealed that pMG1 accumulates single-stranded DNA (ssDNA) intermediate, which indicate i the rolling circle replication (RCR) mechanism of this plasmid. Homology search indicated that ORF II encodes plasmid mobilization protein, and the presence of highly conserved oriT sequence in the upstream of this gene supported this assumption. RT-PCR showed that only ORF I is expressed in vivo. Based on these results, pMG 1 was exploited to construct a shuttle vector, pBES2. It was successfully transformed into Bifidobacterium and maintained stably.
Plant Terpenes Enhance Survivability of Polychlorinated Biphenyl (PCB) Degrading Pseudomonas pseudoalcaligenes KF707 Labeled with gfp in Microcosms Contaminated with PCB
Oh, Eun-Taex ; Koh, Sung-Cheol ; Kim, Eung-Bin ; Ahn, Young-Hee ; So, Jae-Seong ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 463~468
Polychlorinated biphenyl are toxic pollutants and their degradation is quite slow in the environment. Recently, interest if bioremediation using PCB-degrading bacteria has increaset,. In a previous report, plant terpenes (p-cymene, (S)-(-)-limonene,
) have been found to be utilized by a PCB degrader and to induce the biphenyl dioxygenase gene in pure culture. In this study, Pseudomonas pseudoalcaligenes KF707, a PCB-degrading Gram-negative soil bacterium, was used to determine whether the terpene stimulation of PCB degrader occurred in the natural environment. First, P. pseudoalcaligenes KF707 was genetically tagged using a transposon with gfp (green fluorescent protein) as a reporter gone. The population dynamics of P. pseudoalcaligenes KF707 harboring gfp gene in a PCB-contaminated environment was examined with or without terpenoids added to the microcosm. About 10-100-fold increase was found in the population of PCB degraders when terpene was added, compared with control (non-terpenes samples and biphenyl added samples). It was proposed that the gfp-monitoring system is very useful and terpenes enhance the survivability of PCB degraders in PCB-contaminated environments.
Measurement of Free Polysaccharide in Tetanus Toxoid-Conjugate Vaccine Using Antibody/Ammonium Sulfate Precipitation
Yoo, Tae-Hyeon ; Kim, Hyun-Sung ; Park, Sung-Sik ; Bang, Eun-Young ; Oh, Yong-K. ; Kim, Li-Seop ; Kim, Hun ; Hur, Byung-Ki ; Ryu, Yeon-Woo ; Kim, Jong-Su ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 469~472
A method that effectively precipitates capsular polysaccharide of Haemophilus influenzae type b (polyribosylribitol phosphate, PRP) conjugated to tetanus toxoid (TT), PRP TT in a liquid vaccine has been developed to measure free PRP present in TT-conjugate vaccine. The method involves adding anti-TT antibody and ammonium sulfate to precipitate PRP-TT conjugate and measuring free PRP in tile supernatant. This new method provides a complete precipitation of the total PRP-TT, and provides an accurate and reproducible measurements of free PRP. The accuracy of the assay was confirmed by spiking known amounts of unconjugated PRP to PRP-TT conjugate, and the new method was found to have no effect on free PRP while precipitating PRP-TT. The published acid precipitation method did not produce reproducible results due to incomplete precipitation of PRP-TT, especially when the vaccine is formulated in a salt-buffered solution.
Effect of Oxidation-Reduction Potential on Denitrification by Ochrobactrum anthropi SY509
Song, Seung-Hoon ; Yeom, Sung-Ho ; Choi, Suk-Soon ; Yoo, Young-Je ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 473~476
The effect of oxidation-reduction potential (ORP) level on the denitrification by Ochrobactrum anthropi SY509 was investigated under nongrowing condition. The maximum ORP level of nitrate-containing buffer solution was -70∼-80 mV, under which the denitrification took place. By decreasing the initial ORP level, denitrifying enzyme activity was greatly enhanced, which led to higher denitrification efficiency.
Quorum Sensing of Rhodobacter sphaeroides Negatively Regulates Cellular Poly-
-Hydroxybutyrate Content Under Aerobic Growth Conditions
Lee, Jeong-K. ; Kho, Dhong-Hyo ; Jang, Ji-Hee ; Kim, Hye-Sun ; Kim, Kun-Soo ;
Journal of Microbiology and Biotechnology, volume 13, issue 3, 2003, Pages 477~481
The community escape response of Rhodobacter sphaeroides is exerted through the action of CerR and CerI, which code for a LuxR-type regulatory protein and acylhomoserine lactone synthase, respectively. Deletion of chromosomal DNA including cerR and cerI (mutant RI) or insertional interruption of cert (mutant AP3) resulted in two-fold increase in the cellular poly-
-hydroxybutyrate (PHB) content In comparison with the wild-type under aerobic growth conditions. The PHB synthase (PhbC) activities of the cer mutants were doubled, and the enzyme expression was regulated at the level of phbC transcription. Thus, CerR, possibly in response to autoinducer (AI), appears to modulate the PHB content of aerobically grown cells by downregulating phbC transcription.