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 42, Issue 4 - Dec 2006
Volume 42, Issue 3 - Sep 2006
Volume 42, Issue 2 - Jun 2006
Volume 42, Issue 1 - Mar 2006
Selecting the target year
Functional Role of Peptide Segment Containing 1-25 Amino Acids in N-terminal End Region of ErmSF
Jin, Hyung-Jong ;
The Korean Journal of Microbiology, volume 42, issue 3, 2006, Pages 165~171
ERM proteins transfer the methyl group to
in 23S rRNA to confer the resistance to MLS (macrolide-lincosamide-streptogramin B) antibiotics on microorganism ranging from antibiotic producers to pathogens. To define the functional role of peptide segment encompassing amino acid residues 1 to 25 in NTER (N-terminal end region) of ErmSF, one of the ERM proteins, DNA fragment encoding mutant protein deprived of that peptide was cloned and overexpressed in E. coli to obtain a purified soluble form protein to the apparent homogeneity in the yield of 12.65 mg per liter of culture. The in vitro activity of mutant protein was found to be 85% compared to wild type ErmSF, suggesting that this peptide interact with substrate to affect the enzyme activity. This diminished activity of mutant protein caused the delayed expression of antibiotic resistance in vivo, that at fIrst cells expressing mutant protein showed the retarded growth due to the antibiotic action but with time cells inhibited by antibiotic gradually recovered the viability to exert the resistance to the same extent as those with wild type protein.
Effect of Medium Components on the Lipstatin Production by Streptomyces toxytricini
Lim, Mi-Ok ; Yin, Wencui ; Lee, Ji-Seon ; Yu, Yeon-Su ; Kim, Sang-Dal ; Nam, Doo-Hyun ;
The Korean Journal of Microbiology, volume 42, issue 3, 2006, Pages 172~176
In order to increase the productivity of lipstatin by Steptomyces toxytricini, the effect of medium components on the lipstatin production was investigated. Using TSB medium as a basal medium, a variety of carbon sources, nitrogen sources, lipid and fatty acids was supplemented into a fermentation medium. The seed culture of S. toxytricini grown in 25 ml TSB medium at
for 3 days with agitation at 200 rpm was inoculated in the size of 2% in fermentation media containing different components and fermented at
for 60 more hrs. In the examination of the effect of carbon sources, the best cell growth was observed in fermentation media supplemented with glucose or glycerol, but the lipstatin productivity was the highest in media containing lactose or sucrose. Among complex nitrogen sources, yeast extract was the best one for cell growth, but the highest lipstatin production was found in TSB media composed of 1.7% casitone and 0.3% soytone. The increased concentration of triolein as a lipid caused the promotion of cell growth but the significant suppression of lipstatin production. When 0.5% fatty acids were supplemented to fermentation medium, unsaturated fatty acids like linoleic or oleic acid suppressed cell growth as well as lipstatin production, but 2 times higher lipstatin production was achieved by stearic acid, a saturated fatty acid, differently from expectation.
Distribution of Sexually Transmitted Viral Diseases in Busan
Cho, Kyung-Soon ; Na, Young-Ran ; Joe, Hyeon-Cheol ; Lee, Jung-Hee ; Jung, Myung-Ju ;
The Korean Journal of Microbiology, volume 42, issue 3, 2006, Pages 177~184
This study was performed to evaluate the prevalence of high risk Human papilloma virus (HPV), Herpes simplex virus type 1, 2 (HSV-1,2), Hepatitis B virus (HBV) and Human Immuno deficiency virus (HIV) infection with sexual transmitted viral diseases in Busan during 2004 to 2005. six hundred seventy four samples of cervical swabs were tested for sexually transmitted viral diseases. Among the isolated viruses, 23 (3.4%) samples were HPV and 3 (0.4%) and 9 (1.3%) samples were HSV 1 and 2, respectively. Among the 586 serum samples tested for viruses, HSV IgM 121 (3.6%), HSV-1 IgG 487 (83.1%), HSV-2 IgG 135 (23.0%), HBsAg 26 (4.4%), HBeAg 7 (1.2%), and HIV (0%) types were found. HPV genotypes were detected in 16 patients, of which 13 cases were high risk type HPV, 3 cases were low risk type HPV, and multi infection were detected in 7 cases. In the age distribution of the patients, 7.2% of infection tested from cervical swabs occurred in under the age of 20, while 100% of infection was found to occur in those who were 40 years old or older in the serum samples. The outbreak pattern in their occupations was found to be the highest at the health organization (amusement quarter) for the cervical swabs, and at infirmary (commercial sex worker) for the serum samples, respectively.
Antibiotic Susceptibility of Bacteria Isolated from Infected Root Canals
Lim, Sang-Soo ; Kim, Mi-Kwang ; Min, Jeong-Beom ; Kim, Min-Jung ; Park, Soon-Nang ; Hwang, Ho-Keel ; Kook, Joong-Ki ;
The Korean Journal of Microbiology, volume 42, issue 3, 2006, Pages 185~194
The aim of this study was to identify the bacteria isolated from endodontic lesions by cell culture and to determine the antimicrobial susceptibility of them against 8 antibiotics. The necrotic pulpal tissues were collected from 27 infected root canals, which were diagnosed as endodontic infection. Samples were collected aseptically from the infected pulpal tissue of the infected root canals using a barbed broach and a paper point. The cut barbed broaches and paper points were transferred to an eppendorf tube containing
. The sample solution was briefly mixed and plated onto a BHI-agar plate containing 5% sheep blood. The agar plates were incubated in a
anaerobic chamber for 2 to 5 days. The bacteria grown on the agar plates were identified by comparison of 16S rRNA gene (rDNA) sequencing method at the species level. To test the sensitivity of the bacteria isolated from the infected root canals against 8 antibiotics, minimum inhibitory concentrations (MIC) were determined using broth dilution assay. The data showed that 101 bacterial strains were isolated and were identified. Streptococcus spp. (29.7%) and Actinomyces spp. (21.8%) were predominantly isolated. The 9 strains were excluded in antimicrobial susceptibility test because they were lost during the experiment or were not grown in broth culture. The percentage of bacteria susceptible for each antibiotic in this study was clindamycin, 87.0% (80 of 92); tetracycline, 75.0% (69 of 92); cefuroxime axetil, 75.0% (69 of 92); amoxicillin + clavulanic acid (5:1), 71.7% (66 of 92); penicillin G, 66.3% (61 of 92); erythromycin, 66.3% (61 of 92); amoxicillin, 44.6% (41 of 92); and ciprofloxacin, 31.5% (29 of 92). The susceptibility pattern of 8 antibiotics was dependent on the host of the bacteria strains rather than the kinds of bacterial species. These results indicate that antibiotic susceptibility test should be performed when antibiotics are needed for the treatment of infected root canals.
Expression of MEK1 Fusion Protein in Yeast for Developing Cell Based Assay System, a Major Substrate of LeTx
Hwang, Hye-Hyun ; Kim, Joung-Mok ; Choi, Kyoung-Jae ; Park, Hae-Chul ; Han, Sung-Hwan ; Chung, Hoe-Il ; Koo, Bon-Sung ; Park, Joon-Shik ; Yoon, Moon-Young ;
The Korean Journal of Microbiology, volume 42, issue 3, 2006, Pages 195~198
Lethal toxin is a critical virulence factor of anthrax. It is composed two protein: protective antigen (PA) and lethal factor (LF). PA binds to specific cell surface receptors and, forms a membrane channel that mediates entry of LF into the cell. LF is a zinc-dependent metalloprotease, which cleaves MKKs [MAPK (mitogen-activated protein kinase) kinases] at peptide bonds very close to their N-termini. In this study, we suggest application of cell-based assays in the early phase of drug discovery, with a particular focus on the use of yeast cells. We constructed MEK1 expression system in yeast to determine LF activity and approached cell-based assay system to screen inhibitors, in which the results covering the construction of LF-substrate in yeast expression vector, expression, and LF-mediated proteolysis of substrate were described. These results could provided the basic steps in design of cell-based assay system with the high efficiency, rapidly and easy way to screening of inhibitors.
Characterization of Streptococcosis Occurrence and Molecular Identification of the Pathogens of Cultured Flounder in Jeju Island
Jeong, Yong-Uk ; Kang, Chul-Young ; Kim, Min-Ju ; Heo, Moon-Soo ; Oh, Duck-Chul ; Kang, Bong-Jo ;
The Korean Journal of Microbiology, volume 42, issue 3, 2006, Pages 199~204
Streptococcosis of olive flounder(Paralichthys olivaceus) is an important bacterial disease in Jeju island. In this study, we investigated monthly infection pattern of this disease in different size of the flounder fish. Even though the disease occurred throughout the year, the infection ratio was relatively higher in the months with warm water season. The infection was more prevalent in adult flounder over 30 cm total length compare to these of small size fish. Two infectious species of streptococcosis pathogens were detected by multiplex PCR assay. Detection ratios of Streptococcus iniae and S. parauberis reached up to 46% and 54%, respectively, from June 2003 to May 2005 in Jeju island. S. iniae occurred intensively from September to October, whereas S. parauberis reported from March to May. S. iniae and S. parauberis infections of cultured flounder share some common features, but clinical findings showed considerable differences between two diseases. Distended abdomen, protruded anus and ascitic fluid in the peritoneal cavity are evident lesions detected in S. iniae infection, whereas, flounders infected by S. parauberis showed prominent lesions such as darkened surface and haemorrhaging in the non-ocular side. Both streptococcosis pathogens were sensitive to antibiotics, such as ampicillin and amoxicillin. However, S. iniae strains were more sensitive to doxycycline, erythromycin and oxytetracycline than S. parauberis strains.
Application of qDVC Method for Measuring Viable Cells in Lakes
Kim, Mi-Ree ; Seo, Eun-Young ; Choi, Seung-Ik ; Ahn, Tae-Seok ;
The Korean Journal of Microbiology, volume 42, issue 3, 2006, Pages 205~209
For measuring the viable cells in lakes, quantitative direct viable count (qDVC) method is applied. In the qDVC process, the final concentration of glycine is fixed as 2%. For confirming the effectiveness of qDVC for enumerating the viable cells, the viable bacterial numbers were measured by plate count, CTC reduction method and qDVC method at 5 different lakes. Among these 3 methods, the bacterial numbers by qDVC is
times higher than those by the other 2 methods. And by the qDVC method, the viable cells were easily discriminated from dead or dormant cells.
Optimal Conditions for the Production of (+)-Jasmonic acid by Diplodia gossypina ATCC10936
Go, In-Ho ; Kim, Kyoung-Ju ; Kim, Yong-Hwi ;
The Korean Journal of Microbiology, volume 42, issue 3, 2006, Pages 210~215
Diplodia gossypina ATCC10936 produced chiral specific (+)-jasmonic acid (JA) that is the most biologically active form. (+)-JA is a plant growth hormone and also one of the most important aroma compounds responsible for jasmin-like aroma note. In order to develop a commercial bioprocess for the production of (+)-JA, optimal culture conditions for D. gossypina ATCC10936 were investigated. D. gossypina produced (+)-JA using either fructose and glucose as a sole carbon source. As a nitrogen source,
gave relatively high (+)-JA production. The optimal temperature for the production of (+)-JA by D. gossypina was
, and optimal agitation was found to be 200 rpm. D. gossypina produced (+)-JA upto 600 mg/L in SM medium, although the highest level of biomass was obtained in PDMYS medium.
Characterization and Selection of Lactic Acid Bacteria Producing
Lee, Young-Ki ; Choi, Susanna ; Park, Young-Il ; Park, Chan-Sun ; Yoon, Byung-Dae ; Hwang, Yun-Sik ; Kim, Hee-Sik ;
The Korean Journal of Microbiology, volume 42, issue 3, 2006, Pages 216~222
This study was carried out to select the lactic acid bacteria producing
(lactase) and investigate the properties of the
. About 100 strains of lactic acid bacteria showing blue colony on the MRS agar medium containing X-gal were isolated from several kinds of Kimchi. Among them, 2 strains were selected as potential
producers. The selected strains, ET-1 and LA-12, were identified as Lactobacillus fermentum and L. acidophilus, respectively by the analysis of 16S rDNA sequences. They showed relatively high
activity and cellular viability. Their
showed the highest activity at
. And the optimum pHs of the enzymes produced by ET-1 and LA-12 were pH 5.5 and pH 7.0, respectively. They were also highly resistant to artificial gastric juice and bile. Two selected strains showed little change of viable cell number for 3 hr incubation in artificial gastric juice, and maintained the viable cell number at
for 24 hr in 0.3% oxgall after incubation for 2 hours in artificial gastric juice. Based on these results, ET-1 and LA-12 are expected to be applied in dairy industry.
Isolation and Characterization of Insoluble Phosphate-Solubilizing Bacteria with Antifungal Activity
Park, Ki-Hyun ; Son, Hong-Joo ;
The Korean Journal of Microbiology, volume 42, issue 3, 2006, Pages 223~229
To develop multifunctional microbial inoculant, an insluble phosphate-solubilizing bacterium with antifungal activity was isolated from plant rhizospheric soil. On the basis of its morphological, cultural and physiological characteristics and Biolog analysis, this bacterium was identified as Pseudomonas fluorescens RAF15. P. fluorescens RAF15 showed antifungal activities against phytopathogenic fungi Botrytis cinerea and Rhizoctonia solani. The optimal medium composition and cultural conditions for the solubilization of insoluble phosphate by P. fluorescens RAF15 were 1.5% of glucose, 0.005% of urea, 0.3%
, and 0.05% of NaCl along with initial pH 7.0 at
. The soluble phosphate production under optimum condition was 863 mg/L after 5 days of cultivation. The solubilization of insoluble phosphates was associated with a drop in the pH of the culture medium. P. fluorescens RAF15 showed resistance against different environmental stresses like
temperature, 1-4% salt concentration and pH 2-11 range. The strain produced soluble phosphate to the culture broth with the concentrations of 971-1121 mg/L against
, 791-908 mg/L against
, and 844 mg/L against hydroxyapatite, respectively. However, the strain produced soluble phosphate to the culture broth with the concentrations of 15 mg/L against
, and 5 mg/L against
Analysis of Syncytium Formation Mechanism induced by Ecotropic Murine Retrovirus
Bae, Eun-Hye ; Park, Sung-Han ; Jung, Yong-Tae ;
The Korean Journal of Microbiology, volume 42, issue 3, 2006, Pages 230~234
To study the mechanism of syncytium formation, novel syncytia-inducing ecotropic murine retrovirus was used. Our previous result showed that amino acid substitutions at the RBD (receptor binding domain) of envelope glycoprotein contribute to syncytium formation. In this study, we have investigated if this fusion phenomenon could occur with retroviral vectors pseudotyped with the novel syncytia-inducing ecotropic murine leukemia virus Env. We have found that these vectors were not able to mediate virus-to-cell fusion in M. dunni murine cell lines. These findings indicate that syncytia-inducing ecotropic murine leukemia virus is capable of generating syncytia during its replication. There was also no correlation between the level of ecotropic murine leukemia virus receptor (mCAT-1) and the fusogenic effect.
Chitinase and Laccase Expression during the Fruit Body Development in Coprinellus Congergatus
Kim, Yun-Jung ; Park, Hye-Yeon ; Cho, Chung-Won ; Choi, Hyoung-T. ;
The Korean Journal of Microbiology, volume 42, issue 3, 2006, Pages 235~237
When fruit bodies of Coprinellus congregatus were matured, they were autolysed to form black ink. During the developmental changes, cell walls of basidia were degraded. Laccase formed melanin which was the typical black pigment of fungi, and chitinase hydrolyzed the chitin which was a component of fungal cell wall. When laccase and chitinase genes were used as the probe for the Northern analysis to confirm their expression during the fruit body development, both gene expressions were increased as the mushroom was getting matured.