Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
The Korean Journal of Microbiology
Journal Basic Information
Journal DOI :
The Microbiological Society of Korea
Editor in Chief :
Volume & Issues
Volume 38, Issue 4 - Dec 2002
Volume 38, Issue 3 - Sep 2002
Volume 38, Issue 2 - Jun 2002
Volume 38, Issue 1 - Mar 2002
Selecting the target year
A Novel Glycine-Rich Region in Sox4 is a Target for the Proteolytic Cleavage in E. coli
The Korean Journal of Microbiology, volume 38, issue 3, 2002, Pages 153~161
Sox4, a transcription factor, consists of three functional domains: an HMG-box domain as a DNA binding domain, serine rich region as a transactivation domain and glycine rich region (GRR), an unknown functional domain. Although Sox4 is known to be functionally involved in heart, B-cell and reproductive system development, its physiological function remains to be elucidated. We used pGEX expression system to develop a simple and rapid method for purifying Sox4 protein in suitable forms for biochemical studies of their functions. Unexpectedly, we observed that full-length Sox4 appears to be protease-sensitive during expression and purification in E. coli. To map the protease-sensitive site in Sox4, we generated various constructs with each of functional domains of Sox4 and purified as the GST-Sox4 fusion proteins using glutathione beads. We found that the specific cleavage site for the proteolytic enzyme, which exists in E. coli, is localized within the novel GRR of Sox4. Our study suggest that the GRR of Sox4 may a target for the cellular protease action and this cleavage in the GRR may be involved in regulating physiological function of Sox4. Additionally, our study may provide a useful method for investigating the proteolytic cleavage of the target molecule in E. coli.
groES Expression Related to Antifungal Activity of Streptomyces sp. SAR01
The Korean Journal of Microbiology, volume 38, issue 3, 2002, Pages 162~167
To analyse proteins and gene related to antifungal activity, SAR01 strain was isolated from a brown seaweed and identified as Streptomyces sp. by FAME(fatty acid methyl ester) analysis. Antifungal activity deficient mutant(SAR535) of Streptomyces sp. SAR01 was induced by gamma radiation
. It was found that 6 specific protein spots appeared only in SAR01 by 2-D electrophoresis analysis. Among them, a protein of 10 kDa had homology of 96% with 10 kD chaperonin cpn 10 (GroES) by Basic Local Alignment Search Tool(BLAST, NCBI) analysis. SAR535 transformants into which groES was transferred by electroporation revealed antifungal activity newly similar with SAR01 It suggested that groES be supposed to be related to the antifungal activity of Streptomyces sp. SAR01.
Regulation of Intracellular pH by SHC1 in Saccharomyces cerevisiae
The Korean Journal of Microbiology, volume 38, issue 3, 2002, Pages 168~172
Budding yeasts maintain an effective system to regulate intracellular pH in response to environmental pH fluctuation. In a previous study we reported that SHC1 plays a role in cell growth at alkaline condition, not at acid pH. We constructed a null mutant deleted an entire open reading frame for SHC1. To test whether the retardation in cell growth was caused by the absence of intracellular pH buffering capacity, we measured intracellular pH with a pH-sensitive fluorescent dye, C.SNARE. The intracellular pH of the mutant cell was much higher than that of wild-type cells, indicating that the mutant cells lack some types of buffering capacity. We also investigated the level of
content with atomic mass spectroscopy after alkali shock. Wild-type cell showed a higher level of intracellular
content, whereas there was no difference in
level. The result suggested that
is more important in the regulation of intracellular pH in yeasts.
The Functions of the Riboflavin Genes in the lux Operon from Photobacterium Species
The Korean Journal of Microbiology, volume 38, issue 3, 2002, Pages 173~179
The functions of riboflavin synthesis genes ( ribI,II,III and IV) found immediately downstream of luxG in the lux operon from Photobacterium species were identified using the biochemical and genetical analysis. The ribI-III gene codes for protein corresponding to that coded by the second (riboflavin synthase), third (3,4-dihydroxy 2-butanone 4-phosphate synthase/GTP cyclohydrolase II) and fourth (lumazine synthase) gene, respectively, of Bacillus subtilis rib operon with the respective gene procuct sharing 41-50% amino acid sequence identity. Unexpectedly, the sequence of the ribIV product of Photobacterium phosphoreum does not correspond in sequence to the protein encoded by the fifth rib gene of Bacillus subtilis. Instead the gene (ribIV) codes for a polypeptide similar in sequence to GTP cyclohydrolase II of Escherichia coli and the carboxy terminal domain of the third rib gene from Bacillus subtilis. Complementation of Escherichia coli riboflavin auxotrophs showed that the function of the gene products of ribII and ribIV are DHBP synthase and GTP cyclohydrolase II, respectively. In addition the experiment, showing that increase in thermal stability of riboflavin synthase coded by ribIon coexpression with ribIII, provided indirect evidence that the latter gene codes for lumazine synthase.I
The Observation and a Quantitative Evaluation of Viable but Non-Culturable Bacteria in Potable Groundwater Using Epifluorescence Microscopy
The Korean Journal of Microbiology, volume 38, issue 3, 2002, Pages 180~185
The direct viable count (DVC) and plate count (PC) methods was used to measure the number of bacteria in potable groundwater samples collected from bottled water from the market, mineral water, and edible groundwater near the urban areas and the stock farming congested areas. As a result, the number of living bacteria by DVC was comprised 30~80% of the total direct count (TDC), whereas the number of living bacteria by PC was around l~30% of DVC. Such results show that viable but non-culturable (VBNC) bacteria exist in the potable groundwater with high percentages. On the other hand, upon measuring the value from the conventional nutrient broth (NB),
fold diluted nutrient broth (DNB), and R2A broth, the values from the DNB and R2A showed 2~50 times higher than the conventional NB medium. These results indicate that oligotrophic bacterial groups which can multiply in the low nutrient broth abundantly exist in the oligotrophic environment like potable groundwater.
Enteric Virus Detection from Environmental Sample by Oligonucleotide DNA Chip
The Korean Journal of Microbiology, volume 38, issue 3, 2002, Pages 186~191
The usefulness of oligonucleotide DNA chip was evaluated for detection and primary level identification of major waterborne viruses in environmental samples. The enteric waterborne viruses included enterovirus, adenovirus, and rotavirus. Total intracellular RNA of 10 BGM cell plates showing virus-specific cytopathic effects was extracted at the third day after inoculation. The intracellular RNA was then subjected to either enterovirus-specific RT-PCR followed by sequencing analysis, or the DNA chip. Seven out of 10 positive samples in cell culture were positive but the other three sample were turned out to be negative by both RT-PCR and DNA chip analyses. Nucleotide sequencing results and the DNA chip hybridization results of the RT-PCR product were in complete agreement in the identification of the 7 positive samples as enteroviruses. Using the DNA chip, it took only 3∼4 hr to complete detection and primary level identification of target viruses and additional procedures such as gel electrophoresis or nucleotide sequencing were not necessary. We believe that the DNA chip system can be employed as a highly effective and new detection methodology for environmental viruses.
Bacterial Community of Free-living and Aggregated Bacteria at Thawing Period in Lake Baikal
The Korean Journal of Microbiology, volume 38, issue 3, 2002, Pages 192~197
Fluorescent in situ hybridization (FISH) with rRNA-targeted oligonucleotide probes was used to compare the community structures of free-living and aggregated bacteria at thawing period in Lake Baikal. Targeted groups were Eubacteria,
- proteobacteria groups, Cytophaga-Flavobacterium group and Planctomycetales. Total bacterial numbers of free-living bacteria were ranged from
, which were decreasing with depth, while the aggregated bacterial numbers were dramatically increasing from
with depth. The ratios of EUB probe binding cells to DAPI counts were ranged from 52.3 to 74.1% in free-living bacteria, and from 39.6 to 66.7% in the aggregated bacteria, respectively. Community structures of the aggregated bacteria were very different from each free-living bacteria at every depth. At 25 m depth, where the chlorophyll a concentration was highest, both structures were quite different from those of surface layers, rendering the fact that the community structures might be affected by phytoplankton. The vertical profile of community structure of aggregated bacteria is particular. The proportion of
-proteobacteria group was increasing with depth and it was 51.8% at 100 m, but the dominant group was
-pro-teobacteria group at 250 m. Taken together, the biodiversity and succession of aggregated bacteria are quite different from free-living bacteria.
Detection of Poliovirus in Water by Cell Culture and PCR Methods
The Korean Journal of Microbiology, volume 38, issue 3, 2002, Pages 198~204
Poliovirus is a member of enterovirus which causes paralytic poliomyelitis, encephalitis and aseptic meningitis. Since poliovirus is spread by the fecal-oral route and poliovirus-contaminated water could be a potential threat for public health, detection of poliovirus in drinking water resource is important. Infectious poliovirus and poliovirus inactivated by heat or UV were used to test three detection methods such as cell culture method, reverse transcription-polymerase chain reaction (RT-PCR) and integrated cell culture (ICC)-PCR. Infectious poliovirus was detected by all three methods and ICC-PCR was the most sensitive and fast in detecting poliovirus. Inactivated polioviruses could not be detected by cell culture or ICC-PCR methods. On the other hand, heat- inactivated viruses could be detected by RT-PCR. Thus it is suggested that ICC-PCR method is the most sensitive and effective in detecting infectious polioviruses in water sample.
A Characteristics of Phagocytic Plaque on Staphylococcus aureus Layer Formed by Leukocytes of the Alcoholics
The Korean Journal of Microbiology, volume 38, issue 3, 2002, Pages 205~212
This study was conducted to develop a method for direct determination of phagocytic activities in human circulatic systems and to measure the phagocytic activities in human leukocytes from the alcoholics, since phagocytic activity was considered to be very important in human immune mechanism at early stage for the health care of the alcoholics. The subjects for this study were 130 among which 95 males and 3 females were diagnosed as alcoholism and 32 was healthy blood donors. A thin layer of heat-killed Staphylococcus aureus Cowan I was placed on a plastic dish and reacted with whole blood to measure the phagocytic plaque formation by human leukocytes. In order to determine the health conditions of the subjects, some clinical laboratory tests, such as white blood cell counts, hemoglobin contents (Hgb), mean corpuscular volume of red blood cells(MCV), serum electrophoresis, B and T-lymphocytes, T-lymphocyte subtypes and phytohemagglutination test were also implemented. Compared to the non-alcoholism, new and old alcoholic inpatients showed statistically significant differences on levels of Hgb and MCV (p<0.05), but showed that T and B-lymphocyte numbers decreased and Helper T cell/Suppressor T cell ratio (
%) increased. Compared to non-alcoholism, phagocytic plaque activities of leukocytes from alcoholic patients decreased significantly and an unusual pattern in phagocytic plaque was observed, showing a strange body and chain shaped phagocytosis. Based upon these results, it is concluded that a phagocytic-plaques of Staphylococcus aureus Cowan I by leukocytes was very simple and useful method for the early immunological determination of phagocytic activities in alcoholic patients without requiring any special equipments.
Cytopathic Effects of Japanese Encephalitis Virus Structural Proteins in BHK-21 Cells
The Korean Journal of Microbiology, volume 38, issue 3, 2002, Pages 213~220
Inducible expression system for the three structural proteins, capsid (C), precursor membrane (prM/M), and envelop (E) of Japanese encephalitis virus (JEV) was established in BHK-21 cells. Doxycycline, a tetracycline analog, was utilized as an inducer. Transfectants BHK-21/IV (vector only), BHK-21/IC (for C), BHK-21/IP3 (for prM), and BHK-21/IE1 (for E) were selected and cloned in the presence of G4l8 or hygromycin. Transcribed mRNAs for the corresponding genes were observed after doxycycline induction. Effects by the JEV structural gene expression on the transfectants were monitored via cell growth, chromatin condensation, internucleosomal DNA fragmentation, and DNA contents analyses. Clear cell growth retardation and chromatin condensation were observed in all three transfectants while only BHK-2/IC corresponded to the induction status in the DNA fragmentation and DNA content analyses. Combined results, therefore, suggested that JEV capsid protein should be one of the direct and independent factors in apoptotic cell death induced by IEV infection.
Replication and Pathogenesis of Plaque Morphology Mutants Derived from Vero Cells with Japanese Encephalitis Virus Persistency
The Korean Journal of Microbiology, volume 38, issue 3, 2002, Pages 221~229
Japanese encephalitis virus (JEV) persistence was established and maintained in Vero cell culture for over 1 year. Eleven clones of plaque morphology mutant JEV, with large and small plaque sizes, were obtained from the cell culture supernatant. Genomic RNA replication efficiency of the mutants in naive Vero cell appeared to correspond to their different plaque sizes. No significant changes in envelop protein ORF or in non-coding regions at both ends of the RNA genome suggested that there could be an unidentified factor(s) playing role in JEV attenuation. Unlike to the replication of wild-type JEV, the mutants did not induce severe degree of cytopathic effect in Vero cells upon infection. While obvious decrease of Bcl-2 and its mRNA expression and sharp increase of p53 in naive Vero cells infected with either wild-type JEV or the large plaque-forming mutant, those changes were not observed with the small plaque-forming one. Together with these observation, internucleosomal DNA fragmentation and chromosomal DNA profile in the Vero cells infected with the mutants suggest that an overall changes in cytopathic effect in the plaque morphology mutants-infected cells should be primarily due to the reduced genomic RNA replication and the compromised degree of p53-independent apoptosis by the virus infection at least in part.
Antioxidant Activity of Fermented Barley, Wormwood, Sea Tangle, and Soybean
The Korean Journal of Microbiology, volume 38, issue 3, 2002, Pages 230~233
Superoxide is involved in causing inflammation, cancer, and arteriosclerosis in many cases. Taking antioxidant material can be helpful in preventing the diseases. Natural food such as barley, wormwood, sea tangle, and soybean contain antioxidant ingredients. Antioxidant activity increase was determined by fermenting them with microorganism. To determine the activity, 1,1-diphenyl-2-picrylhydrazyl (DPPH) solution was used. When barley, wormwood, sea tangle, and soybean were fermented with Bacillus lichenifomis Bl, antioxidant activities of each fermented product increased 2.6, 1.6, 2.7, and 1.7 folds, respectively. Also, absorbance of fermented soybean was higher than that of soybean at the range of 250~290nm, which might be involved in differences of antioxidant activity of the two. Paraquat suppressed Esherichia coli DH5
growth by making superoxide inside the strain. However, when ethanol extract from fermented soybean was added into the GM (glucose-mineral) media containing the strain, its growth was recovered, suggesting that ethanol extract can move across E. coli, and can function as anti-oxidant material in vivo. Thus, it will be possible to develope antioxidant material from fermented soybean which can be taken orally.