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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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Journal DOI :
The Korean Society for Applied Microbiology and Biotechnology
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Volume & Issues
Volume 12, Issue 6 - Dec 2002
Volume 12, Issue 5 - Oct 2002
Volume 12, Issue 4 - Aug 2002
Volume 12, Issue 3 - Jun 2002
Volume 12, Issue 2 - Apr 2002
Volume 12, Issue 1 - Feb 2002
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Adenovirus-Mediated Antisense Telomerase with Cisplatin Increased the Susceptibility of Cisplatin Resistant Ovarian Cancer Cell Line
Kim, Dae-Shick ; Song, Joon-Seok ; Lee, Kyu-Wan ; Kim, Mee-Hye ; Kim, Kyung-Tai ; Kim, Hysook ; Kim, Young-Tae ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 711~715
Telomerase adds telomeric repeats to chromosomal ends and is known to play an important role in carcinogenesis through cellular immortalization. Since telomerase is an essential pathogenomic factor in malignant tumors, inhibiting telomerase activity is thought to be possible to make telomerase positive tumors more sensitive to cisplatin treatment, which is effective in ovarian cancers, but clinical success Is limited by chemo-resistance. In the present study, cisplatin-sensitive ovarian cancer cell line A2780 and cisplatin-resistant A2780/cp70 cell line were infected with antisense telomerase adenovirus Ad-OA. It was found that the Ad-OA suppressed ovarian cancer cell growth and this effect was mainly due to the induction of caspase-dependent apoptosis. Next, we infected the cisplatin resistant ovarian cancer cell line A2780/ cp70 with Ad-OA and cisplatin concurrently. Interestingly, cisplatin treatment with Ad-Oh was more effective to cisplatin-induced cell death in A2780/cp70 cells compared to cisplatin or the vector group only. These data suggest that cisplatin treatment with Ad-OA may be a new chemo-sensitizer for cisplatin resistant ovarian cancer.
Cloning and Characterization of the
-Lactate Dehydrogenase Gene (IdhL) from Lactobacillus reuteri ATCC 55739
Park, Jar-Yong ; Park, Sun-Jung ; Nam, Su-Jin ; Ha, Yeong-Lae ; Kim, Jeong-Hwan ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 716~721
The ldhL gene encoding the
-(+) lactate dehydrogenase was cloned from Lactobacillus reuteri ATCC 55739 chromosomal DNA and characterized. An internal 750-bp fiagment of ldhL gene was amplified by PCR using primers based on the conserved region of lactobacilli ldhL genes. A genomic library off. reuteri ATCC 55739 was constructed using pBR322, and colony hybridization experiments were performed using the 750-bp fragment as aprobe. One clone harboring a 4.0-kb PstI fragment was identified, and nucleotide sequencing confirmed it as an open reading frame of 972 bp in size in the middle. In addition to IdhL gene, an ORF homologous to Streptococcus pneumoniae TIGR4 hydrolase gene and 3' part of phosphomevalonate kinase gene (mvaK2) were also found on the 4 kb fragment.
-LDH of L. reuteri ATCC 55739 showed the highest degree of homology with the
-LDH of Pediococcus acidilactici (62.4%), fullowed by the
-LDH of Lactobacillus pentosus (58.7%). The size of IdhL transcript determined by Northern blot was 1 kb, indicating the monocistronic nature of IdhL.
Isolation and Cultivation Characteristics of Acetobacter xylinum KJ-1 Producing Bacterial Cellulose in Shaking Cultures
Son, Chang-Jin ; Chung, Seon-Yong ; Lee, Ji-Eun ; Kim, Seong-Jun ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 722~728
Eight strains producing bacterial cellulose (BC) were isolated from rotten fruits and traditionally fermented vinegars. One of the isolated strains from the rotten grape in Gwangju, Korea, maintained a relatively stable BC production in shaking cultures. This isolated strain proved to be Acetobacter xylinum, based on several biochemical and morphological tests. It was shown that the slant-baffled flask was more efficient than the conventional flask for the BC production in shaking cultures. To determine the most suitable carbon and nitrogen sources for the production of BC, various compounds were examined. Fructose was found to be the most effective carbon source with an optimal concentration of 2%. Mixed carbon source (glucose:fructose=1:3) was also better than glucose or fructose alone. Optimal nitrogen source, when basal medium was used, was 10% (v/v) com steep liquor (CSL). When com steep liquor was used with a mixed carbon source (glucose:fructose=1 :3),4% CSL exhibited the best BC production. Based on these results, a defined medium was developed for the BC production by Acetobacter xylinum KJ-1. When this medium was used under optimal culture conditions, the BC production was 7.2 g/1, which was approximately 3 times higher than that with the traditional HS medium.
Molecular Characteristics of Pseudomonas rhodesiae Strain KK1 in Response to Phenanthrene
Kahng, Hyung-Yeel ; Nam, Kyoung-Phile ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 729~734
Radiorespirometric analysis revealed that Pseudomonas sp. strain KKI isolated from a soil contaminated with petroleum hydrocarbons was able to catabolize polycyclic aromatic hydrocarbons such as phenanthrene and naphthalene. The rate and extent of phenanthrene mineralization was markedly enhanced when the cells were pregrown on either naphthalene or phenanthrene, compared to the cells grown on universal carbon sources (i.e., TSA medium). Deduced amino acid sequence of the Rieske-type iron-sulfur center of a putative phenanthrene dioxygenase (PhnAl) obtained from the strain KKI shared significant homology with DxnAl (dioxin dioxygenase) from Spingomonas sp. RW1, BphA1b (biphenyl dioxygenase) from Spingomonas aromaticivorans F199, and PhnAc (phenanthrene diokygenase) from Burkholderia sp. RP007 or Alcaligenes faecalis AFK2. Northern hybridization using the dioxygenase gene fragment cloned from KKI showed that the expression of the putative phn dioxygenase gene reached the highest level in cells grown in the minimal medium containing phenanthrene and
, and the expression of the phn gene was repressed in cells grown with glucose. In addition to the metabolic change, phospholipid ester-linked fatty acids (PLFA) analysis revealed that the total cellular fatty acid composition of KKI was significantly changed in response to phenanthrene. Fatty acids such as 14:0, 16:0 3OH, 17:0 cyclo, 18:1
7c, 19:0 cyclo increased in phenanthrene-exposed cells, while fatty acids such as 10:0 3OH, 12:0, 12:0 2OH, 12:0 3OH, 16:1
7c, 15:0 iso 2OH, 16:0, 18:1
6c, 18:0 decreased.
Determination of Optimum Aggregates of Porcine Hepatocytes As a Cell Source of a Bioartificial Liver
Lee, Doo-Hoon ; Lee, Ji-Hyun ; Choi, Jeong-Eun ; Kim, Young-Jin ; Kim, Sung-Koo ; Park, Jung-Keug ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 735~739
Large quantities of porcine hepatocyte aggregates with various degrees of aggregation (DA) could be obtained by controlling the suspension periods (0,9,24, and 48 h), and by entrapping the hepatocyte aggregates in model materials of encapsulation such as Ca-alginate and type-I collagen gels. The effects of DA on liver-specific functions of hepatocytes were evaluated in order to obtain optimum DA for the cell source of bioartificial liver (BAL) systems. Irregular rugged aggregates (size
) farmed by 24 h of suspension culturing showed peak viability and hepatic functions such as ammonia removal and albumin secretion in the two types of entrapment systems, thus offering themselves as a stable cell source of a BAL system for hepatic functions and scale-up.
Comparison of Rheological Properties of Powder Chlorella sp. Cultivated in Fermentor and Pond
Kang, Ki-Rim ; Lee, Chung-Yung-J. ; Lee, Cherl-Ho ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 740~745
The current study was conducted to identify the differences in the rheological properties of Chlorella sp. powder cultured in a fermentor and in a pond-like environment. Cells. cultured in the same media were harvested and spray dried. The biomass yield from the fermentor culture was 4.7% (dry basis), while that from the pond was 4.3% (dry basis). Measurements of the loose bulk density, tapping test, Hausner's ratio, and compressibility test all revealed differences between the rheological properties of the Chlorella sp. from the two cultivation systems. Although both the fermentor and pond cultured Chlorella sp. showed the same angle of repose, the mean size of the cells was 2.26
, respectively. The weight of the Chlorella sp. tablets cultured in the fermentor and pond was 0.663 g/tablet and 0.593 g/tablet, respectively, while the friability of the tablets was 21% and 41%, respectively. Observation by Transmission Electron Microscope (TEM) showed that the cell wall of the Chlorella sp. cultured in the fermentor was thinner and more spherical than that cultured in the pond, thereby providing the main characteristic rheological properties of the powder.
Effect of Enterococcus faecalis strain PL9003 on Adherence and Growth of Helicobacter pylori
Nam, Hye-Ran ; Ha, Mi-Sun ; Lee, En-Jung ; Lee, Yeon-Hee ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 746~752
The purpose of the present study was to examine the antagonistic activities of Enterococcus faecalis strain PL9003 (PL9003) on Helicobacter pylori. This strain was isolated from infant feces and found to inhibit both the growth of H. pylori and its in vitro adherence to the human gastric cell line MKN-45. The binding of PL9003 to MKN-45 was observed under a light microscope after Cram staining and under a scanning electron microscope. When detected with an FITC-conjugate antibody, both viable and nonviable PL9003 were found to decrease the number of H. pylori bound to MKN-45. When detected by an enzyme-linked immunoabsorbent assay, about 70% of the H. pylori bound on MKN-45 disappeared with the four-1314 addition of viable or nonviable PL9003. The spent culture supernatant (SCS) of PL9003 also decreased the viability of H pylori even after neutralization and pepsin treatment. The above results suggest that PL9003 has a potential as a new probiotic for the stomach.
Extracellular Overproduction of
-Cyclodextrin Glucanotransferase in a Recombinant E. coli Using Secretive Expression System
Lee, Kwang-Woo ; Shin, Hyun-Dong ; Lee, Yong-Hyun ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 753~759
-Cyclodextrin glucanotransferase (
-CGTase) was overproduced extracellularly using recombinant E. coli by transforming the plasmid pECGT harboring a secretive signal peptide. The
-CGTase gene of alkalophilic Bacillus firmus var alkalophilus was inserted into the high expression vector pET20b(+) containing a secretive pelB signal peptide, and then transformed into E. coli BL2l(DE3)pLysS. The optimum culture conditions fer the overproduction of
-CGTase were determined to be TB medium containing 0.5% (w/v) soluble starch at post-induction temperature of
. A significant amount of
-CGTase, up to 5.83 U/ml, which was nine times higher than that in the parent strain B. firmus var. alkalophilus, was overproduced in the extracellular compartment. A pH-stat fed-batch cultivation of the recombinant E. coli was also performed to achieve the secretive overproduction of
-CGTase at a high cell density, resulting in production of up to 21.6 U/ml of
Production and Characterization of Chitosan from Ginseng-Steaming Effluents by Mucor miehei
Kim, Jae-Ho ; Lee, Ki-Sung ; Kim, Na-Mi ; Lee, Jong-Soo ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 760~765
Mucor miehei KCTC 6011, which grew successfully in ginseng-steaming effluents and produced a large amount of chitosan efficiently, was selected from various fungi. Approximately 120 mg of chitosan per g-dry mycelium was maximally produced in 84 h at
when grown in the ginseng-steaming effluent (pH 8.0) supplemented with 0.5% yeast extract and 0.002% CuSO
. Chitosan produced by Mucor miehei KCTC 6011 was identified by the IR-spectra to have deacety lated approximately 56%. Viscosity and molecular weight of the chitosan were 80 cps and
kDa, respectively. The chitosan at 1.5 mg/ml inhibited 73.9% of the mycelium growth of Rhizoctonia solani in 60 h.
Surface Immobilizntion on Silica of Endoxylanase Produced from Recombinant Bacillus subtilis
Kang, Su-Cheol ; Kim, Hye-Jeong ; Nam, Soo-Wan ; Oh, Deok-Kun ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 766~772
The plasmid, pJHKJ4, containing the endoxylanase gene, was introduced into Bacillus subtilis DB 104. The recombinant cells produced 587 unit/ml of endoxylanase at 33 h. The endoxylanase was immobilized covalently on the surface of silica fur effective xylan hydrolysis. The activities of the immobilized and free endoxylanases were optimal at pH 6.5 and 10 mM
. The optimal temperature of the immobilized endoxylanase was
, whereas that of the free endoxylanase was
. Under these optimal conditions, the activity of the immobilized endoxylanase was 1.7 times higher than that of the fee endoxylanase. From microscope photographs, the immobilized endoxylanase was found to be bounded and evenly distributed on the surface of silica, a nonporous solid support. The enzyme kinetics between the immobilized and free endoxylanases was estimated to be uncompetitive, when plotting double-reciprocal plots against xylan concentrations and endoxylanase activities. These results suggest that the higher activity of the immobilized endoxylanase may be due to increased formation of enzyme-substrate complex, because of the easy accessibility of the immobilized enzyme to the polysaccharide-xylan as a high molecular weight substrate.
Cloning and Expression of the Aminopeptidase Gene from the Bacillus lichenformis In Bacillus subtilis
Kim, Jin-Sook ; Lee, In-Soo ; Lee, Seung-Won ; Lee, Young-Phil ; Jung, Chul-Ho ; Kim, Hyung-Cheol ; Choi, Soon-Yong ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 773~779
A gene (hap) encoding aminopeptidase from the chromosomal DNA of Bacillus licheniformis was cloned. The gene is 1,347 bp long and encodes a 449 amino acid preproprotein with a major mature region of 401 amino acids (calculated molecular mass 43,241 Da). N-Terminal sequence of the purified protein revealed a potential presence of N-terminal propeptide. The deduced primary amino acid sequence and the mass analysis of the purified protein suggested that a C-terminal peptide YSSVAQ was also cleaved off by a possible endogeneous protease. Tho amino acid sequence displayed 58% identity with that of the aminopeptidase from alkaliphilic Bacillus halodurans. This bacterial enzyme was overexpressed in recombinant Escherichia coli and Bacillus subtilis cells. Clones containing the intact hap gene, including its own promoter and signal sequence, gave rise to the synthesis of extracellular and thrmostable enzyme by B. subtilis transformants. The secreted protein exhibited the same biochemical properties and the similar apparent molecular mass as the B. lichenzyormis original enzyme.
Detection of Escherichia coli O157:H7 Using Immunosensor Based on Surface Plasmon Resonance
Oh, Byung-Keun ; Kim, Young-Kee ; Bae, Young-Min ; Lee, Won-Hong ; Choi, Jeong-Woo ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 780~786
An immunosensor based on surface plasmon resonance (SPR) with a self-assembled protein G layer was developed for the detection of Escherichia coli O157:H7. A self-assembled protein C layer on a gold (Au) surface was fabricated by adsorbing the mixture of 11-mercaptoundecanoic acid (MUA) and hexanethiol at various molar ratios and by activating chemical binding between free amine (-
) of protein G and 11-(MUA) using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDAC) in series. The formation of a self-assembled protein G layer on an Au substrate and the binding of the antibody and antigen in series were confirmed by SPR spectroscopy. The surface morphology analyses of the self-assembled protein G layer on the Au substrate, monoclonal antibody (Mab) against E. coli O157:H7 which was immobilized on protein G, and bound E. coli O157:H7 extracts on Immobilized Mab against E. coii O157:H7 were performed by atomic force microscopy (AFM). The detection limit of the SPR-based immunosensor for E. coli O157:H7 was found to be about
Development of a Quadrivalent Combined DTaP-HepB Vaccine with a Low Toxicity and a Stable HBsAg Immunogenicity
Bae, Cheon-Soon ; Park, Kwung-Nam ; Ahn, Sang-Jeom ; Kim, Jong-Su ; Hur, Byung-Ki ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 787~792
When developing a combined DTaP-HepB vaccine, toxicity and HBsAg immunogenicity are both important considerations. Thus, for a combined DTaP-HepB vaccine with a low toxicity, the effect of the DTaP content and
, gel concentration on the vaccine toxicity was investigated. Within the range studied, the higher the concentrations, the higher the vaccine toxicity. The importance of the tetanus toxoid content in the combined DTaP-HepB vaccine was also revealed. A higher concentration of the tetanus toxoid was found to have a negative effect on the stability of the HBsAg immunogenicity in the combined vaccine. Accordingly, considering the factors affecting toxicity and HBsAg immunogenicity, a novel DTaP-HepB vaccine (30 Lf/ml of diphtheria toxoid, 5 Lf/ml of tetanus toxoid, 10
PN/ml of acellular pertussis, 24
/ml of HBsAg, and 500
gel) was developed. It has a low toxicity and a stable HBsAg immunogenicity and also satisfies the potency criteria of K-FDA for a combined DTaP vaccine.
Quantitative Analysis of Corynomycolic Acids in Fermentation Broth
Jang, Ki-Hyo ; Park, Yong-Il ; Britz, Margaret-L. ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 793~800
The mycolic acids and fatty acids of mycolic acid- containing bacteria in various types of fluids were analyzed using capillary gas chromatography and mass spectrometry. As model strains, Brevibacterium and Coryebacterium species, which have corynomycolic acids ill the range of
in the whole cell, were investigated. Optimized solvents extraction procedures for the mycolic acids and fatty acids from the culture fluids were: chloroform/methanol (1:2, v/v) as the first extraction solvents fur 4 h; and chlorofunuwater (1:1, v/v) as the second extraction solvents far 1 h. These conditions gave above 95% recovery yields fur mycolic acids from the culture fluids. The mycolic acid profile for the whole cells and the culture fluids were similar fur all the media tested. Thus, the procedure described here could be applied for the identification of mycolic acid-containing bacteria in fermentation broth or liquid from of foods.
Quantitative Analysis of Leuconostoc mesenteroides and Lactobacillus plantarum Populations by a Competitive Polymerase Chain Reaction
Koh, Young-Ho ; Kim, Myoung-Dong ; Han, Nam-Soo ; Seo, Jin-Ho ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 801~806
A multiplex competitive polymerase chain reaction (PCR) method was developed for the rapid identification and quantification of Leuconostoc mesnteroides and Lactobacillus plantarum populations which are the key microorganisms in kimchi fermentation. The strain-specific primers were designed to selectively amplify the target genes encoding 165 rRNA of L. plantarum and dextransucrase of L. mesenteroides. There was a linear relationship between the band intensity of PCR products and the number of colony forming units of each model organism. The PCR quantification method was compared with a traditional plate-counting method f3r the enumeration of the two lactic acid bacteria in a mixed suspension culture and also applied to a real food system, namely, watery kimchi. The population dynamics of the two model organisms in the mixed culture were reliably predictable by the competitive PCR analysis.
A Novel Protein to Bind RCV Core Protein: The Carboxyl Terminus-Truncated Core
Protein of HCV Interacts with E7 Antigen of Human Papilloma Virus Type 18
So, Kwan Young ; Lee, Hyang Ju ; Kang, Kwang Il ; Lee, Hay Young ; Lim, Kyu ; Park, Sang Gi ; Ahn, Jeong Keun ; Kim, Chul Joong ; Lee, Chong Kil ; Kim, Young Sang ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 807~812
In order to analyze the cellular proteins which interact with core protein of hepatitis C virus (HCV), a yeast two-hybrid screening technique was employed. A carboxyl terminus truncated core protein, which contained amino acid residues from the 1st to 120th, was used as a bait to screen cellular proteins. The expression library prepared from HeLa cell was screened and 400 positive clones were selected. The 75 clones from the positive clones were sequenced and analyzed by undergoing the Blast search. Interestingly, 7 out of the 75 clones encoded E7 antigen of human papilloma virus (HPV). We studied in detail the Interaction between the truncated version of HCV core and E7 antigen in vitro. The core
protein expressed in chimeric form with G57 was able to bring down the E7 protein of HPV type 18 expressed in bacteria. It is therefore suggested that the core of HCV might affect the interaction between E7 and a normal cellular tumor suppressor, known as Rb protein.
Synergistic Effect of Lipopolysaccharide and Interferon-
on the Expression of Chemokine Mig mRNA
Lee, Moon-Sook ; Kim, Sung-Kwang ; Kim, Hee-Sun ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 813~818
Expression of monokine induced by IFN-
(Mig) mRNA is well-known to strictly depend on Interferon-
). Lipopolysaccharide (LPS) alone Is weakly effective on Mig mRNA expression in mouse Peritoneal macrophages. This study was undertaken to investigate the synergistic effect of LPS and IFN-
on chemokine Mig gene expression in mouse peritoneal macrophages. Although IFN-
alone was minimally effective, LPS plus IFN-
synergized to produce a high level of Mig mRNh. The synergistic effect of LPS and IFN-
) on Mig mRNA expression was strain-specific. The most effective synergistic effect of LPS/IFN-
on the mRNh expression was found in simultaneous stimulation of LPS/IFN-
. This synergy was modulated at the level of the gene transcription and was not dependent on a new protein synthesis. Synergistic effect of LPS/IFN-
also required the activation of
. Accordingly, these data suggest that LPS/IFN-
synergizes the expression of Mig mRNA through a process that depends on a pretranscriptional level and/or coincident Mig mRNA transcription.
Isolation and Molecular Analysis of Methanol Oxidation Genes in an Obligate Methylotrophic Bacterium, Metheylobacillus sp. Strain SK-5
Choi, Hack-Sun ; Kim, Jin-Kwon ; Ahn, Yeong-Hee ; Koh, Moon-Joo ; Kim, Si-Wouk ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 819~825
Methanol dehydrogenase (MDH) is a key enzyme in the process of methanol oxidation in methylotrophic bacteria. However, information on MDH genes from genus Methylobacillus is limited. In this study, a 6.5-kb HindIII DNA fragment of Methylobacillus sp. SK-5 chromosomal DNA was isolated from the genomic library of the strain by using a degenerate oligonucleotide probe that was designed based on JV-terminal amino acid sequence of the MDH
subunit purified from the strain. Molecular analysis of the fragment revealed four tightly clustered genes (mxaFJGI) involved in the methanol oxidation. The first and fourth genes were very similar to mxaF (77% identity for nucleotides an 78% identity for amino acids) and mxaF (67% Identity for nucleotides and 68% Identity for amino acids) genes, respectively, from Methylovorus sp. SSI. Genes mxaF and mxaI encode
subunits of MDH, respectively. The two subunits were identified from purified MDH from Methylobacillus sp. SK-5. A dendrogram constructed by comparison of amino acid sequences of MDH u subunits suggests that MxaF from Methylobacillus sp. SK-5 belongs to a subfamily cluster of MDH u subunits from
-subgroup Proteobacteria. The subfamily cluster is separated from the other subfamily that consists of
-subgroup Proteobacteria. This study provided information on mn genes from a methylotrophic bacterium in
-subgroup Proteobacteria, which would aid to better develop a gene probe to detect one-carbon metabolizing bacteria.
Characterization of the rfaD Gene Region of Bradyrhizobium japonicum 61A101C
Noh, Jae-Sang ; Kim, Dong-Hyun ; Oh, Eun-Taex ; So, Jae-Seong ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 826~828
In our previous studies, we have cloned and characterized a gene region from Bradyrhizobium japonicum ,which is involved in the synthesis of lipopolysaccharide (LPS). In this study, we have expanded the sequence analysis of the region and found an additional open reading frame (orf), which appeared to be divergently transcribed from the rfaF gene. Sequence alignment of the orf revealed a significant similarity with rfaD genes of Salmonella typhimurium , Escherichia coli, and Neisseria gonorrhoeae. These genes encode a heptose-6-epimerase, which catalyzes the interconversion of ADP -D -glycerol-D-manno-heptose to ADP-L-glycero-D-manno-heptose. This divergent organization of the rfaF and rfaD genes is different from that of other Gram-negative bacteria where two genes form an operon. A rfaD- mutant of E. coli was successfully transformed with plasmid constructs containing the rfaD gene of B. japonicum. Novobiocin sensitivity test showed that the rfaD gene from B. japonicum could complement the rfaD mutation in E. coli, which confirms the functionality of the cloned B. japonicum gene.
PC-766B' and PC-766B, 16-Membered Maerolide Angiogenesis Inhibitors Produced by Nocardia sp. RK97-56
Ko, Hack-Ryong ; Kakeya, Hideaki ; Yoshida, Arika ; Onose, Rie ; Ueki, Masashi ; Muroi, Makoto ; Takatsuki, Akira ; Matsuzaki, Hiroshi ; Osada, Hiroyuki ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 829~833
Angiogenesis is an essential event in a variety of physiological and pathological processes. Therefore, effective inhibition of this event is a promising strategy for treating angiogenesis-related diseases, including cancer. The current study investigated two unique bafilomycin-type macrolide inhibitors of angiogenesls, PC-766B' (1) and PC-766B (2). The strain RK97-56 which produced the inhibitors was identified as Nocardia sp. by chemotaxonomic analyses, and the purification of the inhibitors was guided by their anti-angiogenic activities. PC-766B' (1) and PC-766B (2) exhibited potent inhibitory activities towards endothelial cell migration stimulated by the vascular endothelial growth factor (VEGF).
Effect of 2-NBDG, a Fluorescent Derivative of Glucose, on Microbial Cell Growth
Shin, Dong-Sun ; Oh, Ki-Bong ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 834~837
A fluorescent glucose analogue,2-[N-(7-nitrobenz-2-ox a-1,3-diazol-4-yl) amino] -2- deoxy-D-glucose (2-NBDG), which had previously been developed for the analysis of glucose uptake in living cells, was investigated to determine its biological activity on microorganisms.2-NBDG did not show any inhibitory effect on growth of yeast cells and bacteria. In contrast, 2-NBDG exhibited strong inhibitory effects on filamentous fungal growth. The growth of filamentous fungi was completely inhibited, when 2-NBDG was supplemented as sole carbon source. The inhibitory effect was decreased by the addition of glucose in the test medium. Furthermore, 2-NBDC inhibited chitinase activity of Trichoderma sp. These results suggested that the inhibitory effects of 2-NBDG on filamentous fungi might be partially due to the inhibition of chitinase.
Benzastatin J, a New Demethylated Derivative of Benzastatin B Produced by Controlled Fermentation of Streptomyces nitrosporeus
Kim, Won-Gon ; Yoo, Ick-Dong ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 838~840
Feeding experiments of various derivatives of p-aminobenzamide to benzastatins-producing Streptomyces nitrosporeus were performed to observe whether new biosynthetic analogs of benzastatins were produced. The supplementation of p-aminobenzoic acid to the culture medium of Strepromyces nitrosporeus led to the production of benzastatin J, a new demethylated derivative of benzastatin B, while production of benzastatins A and B increased and benzastatins C-G were not detected.
Rapid and Simple Method to Prepare Functional Pfu DNA Polymerase Expressed in Escherichia coli Periplasm
Chae, Young-Kee ; Jeon, Woo-Chun ; Cho, Kyoung-Suk ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 841~843
Pfu DNA polymerase from Pyrococcus furiosus was expressed in the E. coli periplasm, and the fully active polymerase was partially purified by applying osmotic shock, ammonium sulfate precipitation, and heat treatment. This method represents a new way of expressing and purifying functional Pfu DNA polymerase without the use of chromatography.
Ribozyme-Mediated Replacement of p53 RNA by Targeted Trans-Splicing
Shin, Kyung-Sook ; Bae, Soo-Jin ; Hwang, Eun-Seong ; Jeong, Sun-Joo ; Lee, Seong-Wook ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 844~848
In more than half of human tumors, the p53 tumor suppressor gene is mutated. Thus, restoration of wild-type p53 activity by repair of mutant RNA could be a potentially promissing approach to cancer treatment. To explore the potential use of RNA repair for cancer therapy, trans-splicing group I ribozymes were developed that could replace mutant p53 RNA with RNA sequence attached to the 3'end of ribozymes. By employing a mapping library of ribozymes, we first determined which regions of the p53 RNA are accessible to ribozymes, and found that the leader sequences upstream of the AUG start codon appeared to be particularly accessible. Next, trans-splicing ribozymes were generated that specifically recognized the sequences around these accessible regions. Subsequently, the ribozymes reacted with and altered the p53 transcripts by transferring a 3'exon tag sequence onto the targeted p53 RNA with high fidelity. Thus, these ribozymes could be utilized to repair mutant p53 in tumors, which would revert the neoplastic phenotype.
Copper ion Toxicity Causes Discrepancy between Acetate Degradation and Methane Production in Granular Sludge
Bae, Jin-Woo ; Rhee, Sung-Keun ; Jang, Am ; Kim, In-S. ; Lee, Sung-Taik ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 849~853
Metal ions have an adverse effect on anaerobic digestion. In an acetate degradation test of upflow of anaerobic sludge blanket granules with
, not all of the acetate that disappeared was stoichiometrically converted to methane. In the presence of 400 mg/g-VSS (volatile suspended solids)
, only 26% of the acetate consumed was converted to methane. To study acetate conversion by other anaerobic microorganisms, sulfate and nitrate reductions were investigated in the presence of
Sulfate and nitrate reductions exhibited more resistance to
than methanogenesis, and the granules reduced 2.2 mM and 5.4 mM of nitrate and sulfate, respectively, in the presence of 400 mg/g-VSS copper ion. However, the acetate degraded by sulfate and nitrate reductions was only 24% of the missing acetate that could have been stoichiometrically converted to
. Accordingly, 76% of the acetate consumed appeared to have been converted to other unknown compounds.
Antimicrobial Effects of Ocotillone Isolated from Stem Bark of Ailanthus altisshima
Lee, Dong-Gun ; Chang, Young-Su ; Park, Yoon-Kyung ; Hahm, Kyung-Soo ; Woo, Eun-Rhan ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 854~857
Bioassay-directed chromatographic fractionation of a methylene chloride extract of Ailanthus altisshima indicated the presence of 20(S), 24(R), epoxy-25-hydroxydammarane-3-one (compound 1, ocotillone) which was isolated from this plant, for the first time. Antimicrobial activity of compound 1 was measured by inhibition of bacterial and fungal cells growth and by a hemolytic assay with human erythrocytes, respectively. The results revealed that compound 1 had potent antibacterial activity against Cram-negative bacteria, P. aeruginosa and S. typhimurium, that were without hemolytic activity, whereas it had weak antimicrobial activity against Gram-positive bacteria and fungi. These results demonstrated that the compound 1 has more antibacterial activity against 6ram-negative bacteria, which have no hemolytic activity, than Gram-positive bacteria and fungi. This is the first report on the biological activities of the compound 1.
Antibacterial and Antifungal Activities of a Naphthoquinone Derivative Isolated from the Fruits of Catalpa ovata G.
Kuk, Ju-Hee ; Ma, Seung-Jin ; Moon, Jae-Hak ; Kim, Kil-Yong ; Choi, Sang-Ho ; Park, Keun-Hyung ;
Journal of Microbiology and Biotechnology, volume 12, issue 5, 2002, Pages 858~863
An antimicrobial compound was isolated from the MeOH extract of Catalpa ovata G.
fruits, and its structure was Identified as 4,9-dihydroxy-2,2-dimethyl-3,4-Uihydronaphtho[2,3-b]pyran-5,10-dione (HMNP). The antimicrobial activity of the Un was determined by measuring the dose-response inhibiton of microbial growth in liquid cultures and then compared with that of lapachol, a well known antimicrobial 1,4-naphthoquinone. The antimicrobial activity of the HMNP was more effective than that of lapachol over a wide range of test organisms. Gram-positive bacteria, yeast, and fungi (
) were found to be more sensitive to the HMNP than Cram-negative bacteria (
). The HMNP also inhibited germination of spores of many fungi. The morphological defurmation of the fungal spores was induced by the treatment of HMNP, as illustrated by Scanning Electron Microscopy (SEM).