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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Microbiology and Biotechnology Letters
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Journal DOI :
The Korean Society for Applied Microbiology and Biotechnology
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Volume & Issues
Volume 39, Issue 4 - Dec 2011
Volume 39, Issue 3 - Sep 2011
Volume 39, Issue 2 - Jun 2011
Volume 39, Issue 1 - Mar 2011
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Antimicrobial Effects and Mechanism(s) of Silver Nanoparticle
Hwang, In-Sok ; Cho, Jae-Yong ; Hwang, Ji-Hong ; Hwang, Bo-Mi ; Choi, Hye-Min ; Lee, June-Young ; Lee, Dong-Gun ;
Microbiology and Biotechnology Letters, volume 39, issue 1, 2011, Pages 1~8
The antimicrobial effects of silver (Ag) ion or salts are well known. Recently, silver nanoparticle is attracting an interest in a wide variety of fields since it has been known to be safe and effective as an antimicrobial agent against a broad spectrum of microorganisms. Although silver nanoparticle has been applied to various kinds of products owing to its potent antimicrobial activity, the effects of silver nanoparticle on microorganisms and antimicrobial mechanism have not been revealed clearly. In this paper, we summarized the characteristics, antimicrobial activities and mechanisms, cytotoxicity and applicability of silver nanoparticle.
Characterization of a PyrR-deficient Mutant of Bacillus subtilis by a Proteomic Approach
Seul, Keyung-Jo ; Cho, Hyun-Soo ; Ghim, Sa-Youl ;
Microbiology and Biotechnology Letters, volume 39, issue 1, 2011, Pages 9~19
The Bacillus subtilis pyrimidine biosynthetic (pyr) operon encodes all of the enzymes for the de novo biosynthesis of Uridine monophosphate (UMP) and additional cistrones encoding a uracil permease and the regulatory protein PyrR. The PyrR is a bifunctional protein with pyr mRNA-binding regulatory funtion and uracil phosphoribosyltransferase activity. To study the global regulation by the pyrR deletion, the proteome comparison between Bacillus subtilis DB104 and Bacillus subtilis DB104
pyrR in the minimal medium without pyrimidines was employed. Proteome analysis of the cytosolic proteins from both strains by 2D-gel electrophoresis showed the variations in levels of protein expression. On the silver stained 2D-gel with an isoelectric point (pI) between 4 and 10, about 1,300 spots were detected and 172 spots showed quantitative variations in which 42 high quantitatively variant proteins were identified. The results showed that production of the pyrimidine biosynthetic enzymes (PyrAA, PyrAB, PyrB, PyrC, PyrD, and PyrF) were significantly increased in B. subtilis DB104
pyrR. Besides, proteins associated carbohydrate metabolism, elongation protein synthesis, metabolism of cofactors and vitamins, motility, tRNA synthetase, catalase, ATP-binding protein, and cell division protein FtsZ were overproduced in the PyrR-deficient mutant. Based on analytic results, the PyrR might be involved a number of other metabolisms or various phenomena in the bacterial cell besides the pyrimidine biosynthesis.
Phylogenetic Analysis of Sorangium cellulosum Strains Based on Cellulase Gene Sequences
Lee, Han-Bit ; Youn, Jin-Kwon ; Cho, Kyung-Yun ;
Microbiology and Biotechnology Letters, volume 39, issue 1, 2011, Pages 20~28
Phylogenetic analysis of two cellulase genes, xynB1 and bglA2, and the groEL1 gene from 34 Sorangium cellulosum strains isolated in Korea suggested that there are at least five subgroups in S. cellulosum, which is the most proficient producer of secondary metabolites among myxobacteria. This analysis also revealed diversity among the isolated S. cellulosum. It appeared that at least 30 out of 34 strains are different each other.
Inhibition of Quorum Sensing and Biofilm Formation by Synthetic Quorum Signal Analogues in Pseudomonas aeruginosa
Kim, Soo-Kyoung ; Kim, Cheol-Jin ; Yoon, Je-Yong ; Lee, Joon-Hee ;
Microbiology and Biotechnology Letters, volume 39, issue 1, 2011, Pages 29~36
Pseudomonas aeruginosa is an opportunistic pathogen that causes various infections on urinary track, cornea, respiratory track, and burn wound site, and mainly relies on quorum sensing (QS) for its virulence. To control the infectivity of P. aeruginosa, we previously synthesized the structural analogues of a major QS signal, N-3-oxododecanoyl homoserine lactone (3OC12-HSL) to use as a QS inhibitor. Two of them (5b and 5f) had been confirmed to have an inhibitory effect on LasR, a major QS signal receptor of P. aeruginosa in the screening by the recombinant Escherichia coli reporter. To further evaluate these compounds, we tested their efficacy to control the QS and virulence of P. aeruginosa. Unlike the result from E. coli reporter, both 5b and 5f failed to affect the LasR activity in P. aeruginosa, but instead they selectively affected the activity of QscR, another 3OC12-HSL receptor of P. aeruginosa. Interestingly, their effect on QscR was complex and opposite to what we obtained with E. coli system. Both 5b and 5f enhanced the QscR activity at the low concentration range (< 10
), but high concentration of 5f (
1 mM) strongly inhibited QscR. While 5b and 5f didn't affect the production of proteases, the key virulence factor, they significantly reduced the biofilm formation that is important in mediating chronic infections. Especially, 5f inhibited the initial attachment of P. aeruginosa, rather than the biofilm maturation. Based on our results, we suggest that 5f can be applied for an anti-biofilm agent without increasing virulence of P. aeruginosa.
Isolation and Identification of a Streptomyces sp. that Produces Antibiotics Against Multidrug - Resistant Acinetobacter baumannii
Rhee, Ki-Hyeong ;
Microbiology and Biotechnology Letters, volume 39, issue 1, 2011, Pages 37~42
I isolated the actinomycete strain KH223 from soil samples collected from the Kye Ryong mountain area. This strain is antagonistic to the multidrug-resistant Acinetobacter baumannii. KH223 was confirmed as belonging to the genus Streptomyces based on the scanning electronmicroscopy(SEM) observations of the diaminopimelicacid(DAP) type and morphological and physiological characteristics. Comparison of the 16S rDNA nucleotide sequences revealed that KH223 has a relationship with Streptomyces galbus. Production of antibiotics by KH223 was most favorable when cultured on a glucose, polypeptone, and yeast extract(PY) medium for 6 days at 27
. The supernatant was found to exhibit an antimicrobial effect on various kinds of bacteria and fungi. Particularly, butanol and ethylacetate extracts of KH223 and cyclo(trp-trp) exhibited significant activity against A. baumannii at concentration ranges of 0.8-12.5
/mL and 12.5
/mL, respectively. Moreover, in contrast to cyclo(trp-trp) had shown to activity against Micrococcus luteus JCM 1464 at the concentration of 12.5
/mL, the butanol extract of KH223 showed significant activity against Bacillus subtilis IAM 1069 and Micrococcus luteus JCM 1464 at the concentration of 0.4 and 0.8
/mL, respectively. These results suggest that KH223 may have a great potential in the production of new antibiotics to combat multidrug-resistant pathogens and further studies may be warranted for the same.
Wine Making using Campbell Early Grape with Different Yeasts
Kim, Kyeong-Hwan ; Han, Gi-Dong ;
Microbiology and Biotechnology Letters, volume 39, issue 1, 2011, Pages 43~48
Physicochemical and organoleptic characteristics of Campbell Early red wines made by traditional method were investigated. The pH values of all Campbell Early red wines were ranged 3.0~3.3 during fermentation. The acidity value of Campbell Early red wine made by traditional method was 0.4~0.9%. Sucrose and alcohol contents were 6~7 Brix and 13.2~14.4% at the end of fermentation, respectively. Campbell Early red wine had the high sensory scores for color, aroma, taste, sharpness, after taste, and overall balance. Because Campbell Early red grapes are well fermented due to the rich fermentative sugar content, Campbell Early red wines made by adding EC-1118 yeast were shown to be the most appropriate.
Isolation and Identification of a Bacillus sp. producing
-glucosidase Inhibitor 1-deoxynojirimycin
Kim, Hyun-Su ; Lee, Jae-Yeon ; Hwang, Kyo-Yeol ; Cho, Yong-Seok ; Park, Young-Shik ; Kang, Kyung-Don ; Seong, Su-Il ;
Microbiology and Biotechnology Letters, volume 39, issue 1, 2011, Pages 49~55
Thirty Streptomyces sp. and 200 Bacillus sp. isolated from Korean soils and traditional foods were screened for their abilities to inhibit
-glucosidase and produce 1-deoxynojirimycin (DNJ). This screening identified a Bacillus sp. bacterium that strongly inhibited
-glucosidase and produced high levels of DNJ from Chungkookjang, a Korean traditional food. The bacterium was characterized in terms of its biochemical and molecular biological properties such as sugar utilization, cellular quinone composition, cell wall fatty acid composition, and 16S rDNA sequence. In addition, scanning electron microscopy was used to visualize the morphology of the bacterium. These analyses identified the bacterium as B. subtilis, a bacterium with Generally Recognized as Safe (GRAS) status. The selected strain was named B. subtilis MORI.
Quality Characteristics of Seoktanju Fermented by using Different Commercial Nuruks
Choi, Ji-Ho ; Jeon, Jin-A ; Jung, Seok-Tae ; Park, Ji-Hye ; Park, Shin-Young ; Lee, Choong-Hwan ; Kim, Tack-Joong ; Choi, Han-Seok ; Yeo, Soo-Hwan ;
Microbiology and Biotechnology Letters, volume 39, issue 1, 2011, Pages 56~62
We investigated quality characteristics of Seoktanju (one of the Korean traditional rice wine) which was fermented using five kinds of Korean commercial Nuruks. The purpose of this study was to research what effects on the quality of Seoktanju by using different Nuruks. We analyzed general component such as each mash's temperature change patterns, pH, titrable acidities, reducing sugar contents, volatile acids, and sugar contents during fermentation periods and studied sensory evaluation of produced Seoktanju (10 days). On the whole, temperature change patterns in the each mashes were depend on room temperature. All Seoktanju's pH was reduced rapidly up to three days after first mashing (pH 3.13-3.57) and after that was increased gradually. The end of fermentation pH was pH 3.6-4.05. Mostly, acidities were indicated high(0.59%) and Nuruk-B was showed highest acid value. These results seems to be different as occasion organic acids producing activity depend on the number of yeast, material contents, optimal temperature in the each mashes by fungi and lactic acid bacteria in Nuruks. In reducing sugar contents and sugar contents, Nuruk-C treatment were showed the highest value with 5.36%,
, respectively and alcohol content was lowest with 8.6%. In the five kinds of reproduced Seoktanju, alcohol content was the highest in the treated Nuruk-A group. Volatile acid value was the highest with 132.6~263.7 ppm at the 3 day after first mashing day but as the fermentation time goes on, it was reduced sharply by 5.25~5.94 ppm. Sensory evaluation was performed with 5 point scale, the Seoktanju using Nuruk-D was presented by 4 point, while Nuruk-A was presented lowest by 2.77 point on overall acceptability.
Antibacterial and Antioxidative Activity of Lespedeza cuneata G. Don Extracts
Lee, Hye-Jin ; Lim, Gyu-Nam ; Park, Min-A ; Park, Soo-Nam ;
Microbiology and Biotechnology Letters, volume 39, issue 1, 2011, Pages 63~69
In this study, the antibacterial activity and the antioxidative effects, inhibitory effects on tyrosinase of Lespedeza cuneata G. Don extracts were investigated. MIC value of ethyl acetate fraction from L. cuneata G. Don on P. ovale (0.125%) showed that the antibacterial activity of the ethyl acetate fraction was higher than methyl paraben. The aglycone fraction of L. cuneata G. Don (14.63
/mL) showed the most prominent the free radical (1,1-diphenyl-2-picryl-hydrazyl, DPPH) scavenging activity (
). Reactive oxygen species (ROS) scavenging activities (
) of L. cuneata G. Don fraction on
system were investigated using the luminol-dependent chemiluminescence assay. The aglycone fraction of L. cuneata G. Don (0.07
/mL) showed the most prominent ROS scavenging activity. The protective effects of extract/fractions of L. cuneata G. Don on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The L. cuneata G. Don extracts suppressed photohemolysis in a concentration dependent manner (1 ~ 50
/mL). The inhibitory effects (
) of L. cuneata G. Don extracts on tyrosinase were determined with ethyl acetate fraction (104.83
/mL) and aglycone fraction (27.55
/mL) of L. cuneata G. Don extract. These results indicate that L. cuneata G. Don extract/fractions can function as high potential as bactericide against the pathogenic bacteria and antioxidant in biological systems, particularly skin exposed to UV radiation by scavenging
and other ROS, and protect cellular membranes against ROS. Extract/fractions of L. cuneata G. Don could be applicable to new functional cosmetics for antiaging, antioxidant, and antibacterial activity.
Development and Application of PCR-Based Weissella Species Detection Method with recN Gene Targeted Species-Specific Primers
Lee, Myeong-Jae ; Cho, Kyeung-Hee ; Han, Eung-Soo ; Lee, Jong-Hoon ;
Microbiology and Biotechnology Letters, volume 39, issue 1, 2011, Pages 70~76
PCR-based Weissella species-specific detection method was developed to apply for the discrimination of Korean and Chinese kimchi by detecting a Weissella species only found in Korean or Chinese kimchi. PCR primers were designed from the species-specific sequence in the recN gene of each species. The primers allowed the species-specific detection and identification of nine species in the genera Weissella, and were successfully applied to the detection of W. cibaria, W. confusa, W. koreensis, and W. soli in kimchi with 20 ng template DNA. W. cibaria, W. confusa, and W. koreensis were detected from the Korean kimchi samples tested but W. soli was not detected. However, the four species were detected from Chinese kimchi samples. PCR-based W. soli-specific detection could not be perfectly applied as the Chinese kimchi discriminating method but has significance as an approach to evaluate the potential of scientific verification method based on the difference of microbial community.
Antibacterial Activity of Silver-nanoparticles Against Staphylococcus aureus and Escherichia coli
Kim, Soo-Hwan ; Lee, Hyeong-Seon ; Ryu, Deok-Seon ; Choi, Soo-Jae ; Lee, Dong-Seok ;
Microbiology and Biotechnology Letters, volume 39, issue 1, 2011, Pages 77~85
The antibacterial activities of silver nanoparticles (Ag-NPs) were studied with respect to Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli by observing the bacterial cells treated or not with Ag-NPs by FE-SEM as well as measuring the growth curves, formation of bactericidal ROS, protein leakage, and lactate dehydrogenase activity involved in the respiratory chain. Bacterial cells were treated with Ag-NPs powder, and the growth rates were investigated under varying concentrations of Ag-NPs, incubation times, incubation temperatures, and pHs. As a result, S. aureus and E. coli were shown to be substantially inhibited by Ag-NPs, and the antibacterial activity of Ag-NPs did not fluctuate with temperature or pH. These results suggest that Ag-NPs could be used as an effective antibacterial material.
Bioremediation of Diesel-Contaminated Soils by Natural Attenuation, Biostimulation and Bioaugmentation Employing Rhodococcus sp. EH831
Lee, Eun-Hee ; Kang, Yeon-Sil ; Cho, Kyung-Suk ;
Microbiology and Biotechnology Letters, volume 39, issue 1, 2011, Pages 86~92
Three bioremediation methods, natural attenuation (NA), biostimulation (BS) and bioaugmentation (BA) were applied to remediate diesel-contaminated soil, with their remediation efficiencies and soil microbial activities compared both with and without surfactant (Tween 80). BA treatment employing Rhodococcus sp. EH831 was the most effective for the remediation of diesel-contaminated soil at initial remediation stage. On the addition of surfactant, no significant effect on the remediation performance was observed. A negative correlation was found between the dehydrogenase activity (DHA) and residual concentration of total petroleum hydrocarbons (TPHs) at below 20,000 mg-
, as follows: DHA (
) = -0.02
TPHs concentration (mg-
) + 425.76 (2500
20000, p < 0.01).
Functional Analysis and Selection of Second-site Revertant of Escherichia coli 16S rRNA of C770G
Ha, Hye-Jeong ; Ryou, Sang-Mi ; Lee, Kang-Seok ; Jeon, Che-Ok ;
Microbiology and Biotechnology Letters, volume 39, issue 1, 2011, Pages 93~96
It has been shown that a nucleotide substitution at position 770 in Escherichia coli 16S rRNA, which is implicated in forming the evolutionary conserved B2c intersubunit bridge, has a detrimental effect on ribosome function. In order to isolate second-site revertants that complement ribosomes containing C770G, we performed a random mutagenesis of the 16S rRNA gene and selected clones that could produce more CAT protein translated by specialized ribosome. One of the clones contained two nucleotide substitutions at positions 569 and 904 (C569G and U904C) and these mutations partially complemented the loss of protein-synthesis ability caused by C770G. Further studies using the isolated revertant will provide information about which part of 16S rRNA is interacting with C770 and the consequence of the structure formed by these interactions in the process of protein synthesis.