• Food Engineering Progress
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• v.14 no.3
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• pp.263-270
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• 2010

An alkalophilic microorganism named DK-2386, which produces xylanase, was isolated from soil of Taejo-mountain, Cheonan-si, Chungnam, Korea. The isolated strain was characterized as Gram-positive, with size of 0.4${\times}$2.5 ${\mu}$m, spore forming, anaerobic, catalase positive, possessed with hydrolysis abilities of casein, starch, sodium carboxy methyl cellulose, and xylan, reduction of nitrate to nitrite, resistant against lysozyme, urease positive, and motility positive. The color of culture broth was reddish yellow. The strain DK-2386 was identified as Bacillus agaradhaerens by whole cell fatty-acid composition analysis and 16S rDNA sequence analysis. However, it was not identical to Bacillus agaradhaerens 40952 obtained from the Korean Culture Center of Microorganism in its colour of culture broth. Therefore, we have named the newly isolated strain as Bacillus agaradhaerens DK-2386.

• Korean Journal of Microbiology
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• v.30 no.6
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• pp.501-506
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• 1992

An alkalophilic Vibrio sp. RH530 showing high proteolytic activity was isolated form soil samples by enrichment culture. The activity staining using gelatin SDS- polyacrylamide gel electrophoresis (PAGE ) revealed that the strain produced an alkaline major protease (Apr B) with a size of 27 kDa, and at least six minor proteases. The apparent sizes of four of the minor proteases were approximately 45, 28, 22 and 19 kDa. Apr B and five of the minor proteases were inhibited by serine protease inhibitors including PMSF and DFP, suggesting that they are serine proteases. One of the minor proteases was inhibited by metalloprotease inhibitors, not by serine protease inhibitors, indicating it to be a metalloprotease. Furthermore, the activities of Apr B and Prt 3 were not inhibited by SDS in the reaction mixture. The production of Apr B and some of the minor proteases was specifically affected by culture temperature (30 to 37.deg.C) and pH (7 to 10). The production of Apr B. Prt 2, Prt 5 and Prt 6 was mainly affected by culture temperature, while Prt 4 by culture pH. Prt 1 and Prt 3 were not affected by neither of these factors.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.529.1-529
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• 1986

For isolation of the CMCase gene of the alkalophilic Bacillus sp. strain N-4 to analyze their genetic information for the multicomponents of the cellulase, Bscherichia coli K12 and plasmid DNA pBR322 was used as host-vector system. After the digestion of purified chromosomal DNA and plasmid DNA pBR322 with HindIII, these were ligated. The ligated DND were transformed into Escherichia coli, and recombinant plasmid 107 carried the gene coding for CMCase was constructed. The CMCase produced by Escherichia coli cells containing plasmid DNA pYBC107 was found in the cells as intracellular enzyme and nearly 60% of the total CMCase activity was localized in cellular fraction. Also, the optimum pH for the reaction of CMCase produced by Escherichia coli was appeared at pH .8.0 and the enzyme was stable between pH 7.0 and pH 8.0.

• Journal of Microbiology
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• v.33 no.4
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• pp.344-349
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• 1995

The alkalophilic bacterium, Xanthomonas sp. JK311, producing extracellular proteases, was isolated from soil. Xanthomonas sp. JK311 produced five extracellular proteases that are all metalloproteases. Four of them were resistant against 1% SDS. Chromosomal DNA of the Xanthomonas sp. JK311 was digested with BamHI and cloned into PUC19. Among E. coli strain HB101 transformants, a clone secreting the proteases was screened through halo formation on skim-milk agar plate and by Southern blot analysis. It had the recombinant plasmid pXEP-1 containing the 7.5 kb-BamHI DNA fragment and produced three extacellular proteases. Their protease properties corresponded to those of Xanthomonas sp. JK311.

• Journal of Microbiology
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• v.41 no.4
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• pp.345-348
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• 2003

The bio-mediated production of calcite crystals by calcinogenic bacteria has great applicable value for the restoration of deteriorated calcareous monuments, because of its high purity and coherency. An investigation of the conditions for calcite production by an alkalophilic Bacillus amyloliquefaciens CMB01 strain was made. Optimal calcite precipitation occurred when the bacterium was cultured at pH 8.0 and 30$^{\circ}C$, and in B4 medium that consisted of 0.4% yeast extract, 0.5% glucose, and 1.5% calcium acetate. Calcium ion of the bacterially induced calcite was analyzed by an inductively coupled plasma (ICP) spectrophotometer. Optical and scanning electron microscopy (SEM) of the calcite revealed a typical rombohedral polycrystalline structure.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1142-1149
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• 2004

Streptococcus mutans has the capacity of inducing dental caries. Thus, to develop a novel way of preventing dental caries, a cell wall hydrolase-producing strain was isolated and its characteristics were investigated. Among 200 alkalophilic strains isolated from soil, 8 strains exhibited lytic activities against Streptococcus mutans. However, strain YU5215 with the highest cell wall hydrolase activity was selected for further study. Strain YU5215 was identified as a novel strain of Bacillus based on analyzing its 16S rDNA sequence and Bergey's Manual of Systematic Bacteriology, and thus designated as Bacillus mutanolyticus YU5215. The optimal conditions for the production of the cell wall hydrolase from Bacillus mutanolyticus YU5215 consisted of glucose ($0.8\%$), yeast extract ($1.2\%$), polypeptone ($0.5\%$), $K_{2}HPO_{4}\;(0.1\%$), $MgSO_{4}{\cdot}7H_{2}O$ ($0.02\%$), and $Na_{2}CO_{3}\;(1.0\%$) at pH 10.0. Bacillus mutanolyticus YU5215 was cultured at 30^{circ}C for 72 h to produce the cell wall hydrolase, which was then purified by acetone precipitation and CM-agarose column chromatography. The molecular weight of the lytic enzyme was determined as 22,700 Da by SDS-PAGE. When the cell wall peptidoglycan of Streptococcus mutans was digested with the lytic enzyme, no increase in the reducing sugars was observed, while the free amino acids increased, indicating that the lytic enzyme had an endopeptidase-like property. The amino terminus of the cell wall peptidoglycan digested by the lytic enzyme was determined as a glutamic acid, while the lytic site of the lytic enzyme in the Streptococcus mutans peptidoglycan was identified as the peptide linkage of L-Ala and D-Glu.

• Korean Journal of Agricultural Science
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• v.25 no.1
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• pp.124-130
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• 1998

An alkalophilic bacterium, the strain AC-711 as a potent producer of alkaline cellulase, was selected among many isolates from soil environments. Morphological, physiological and chemical characteristics of the strain AC-711 suggested that it belongs to the genus Pseudomonas according to the Bergey's Manual of Systematic Bacteriology, however the G+C mol% (54.43) of its chromosomal DNA is lower than the normal values of the genus. The major cell wall fatty acids were determined as 15:0 and 17:0 anteiso. The production of alkaline CMCase by the strain was maximal when grown on the mediun containing 1% carboxymethyl cellulose, 0.1% $KH_2PO_4$, 0.02% $CoCl_2$, 0.02% Tween 80, 0.5% $Na_2CO_3$, 0.8% yeast extract, pH 10.3 at $30^{\circ}C$ for 3 days, and the most of enzyme was excreted into culture mediun.

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.545-551
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• 1989

Thermostable alkaline protease of alkalophilic Bacillus sp. No. 8-16 has been purified, and the properties of the enzyme investigated. The characteristic point of the organism used is especially good growth in alkaline and thermal condition. The alkaline protease of the strain No. 8-16 was purified from crude enzyme by acetone precipitation, CM-cellulose ion exchange chromatography, Sephadex G-100 and Sephadex G-75 gel filtration. Through the series of chromatograpies, the enzyme was purified to homogeneity with specific activity of 37 fold higher than that of the crude broth. Characteristics of the purified enzyme were as follow; $K_m$ value for the enzyme was 1.3 mg/ml, the alkaline protease showed a maximal activity at 7$0^{\circ}C$ and from the pH 6.0 through 12.0, and stable for 1 hr. at 6$0^{\circ}C$. The moleclar weight of the enzyme was estimated to be 33,000 by Sephadex G-100 gel filtration. The activity of the alkaline protease was inhibited by iodoacetic acid and Ag$^+$, Hg$^+$, PMSF (phenylmethylsulfonyl fluoride), and activated by $Ca^{2+}$ and Mn$^{2+}$.

• Microbiology and Biotechnology Letters
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• v.29 no.2
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• pp.67-71
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• 2001

Isolation and Growth Characteristics of AIkalophilic Bacillus sp. for Removal of Anthraquinone Dye. Kim, Jeong-Mog. School of Environmental Information, Taekyeung College, Kyungsan, 712-850, Korea -Alkalophilic strain degrading and decolorizing anthraquinone dye, Remazol brilliant blue R was isolated from natural system and named as Bacillus sp. ARB!. The optimal temperature and pH of Bacillus sp. ARBI were 35°C and 9.0, respectively. The pH of culture media during the fermentation were changed from 10 and 10.5 of initial values to 9.3 and 9.4 after 40 hrs, respectively. Decolorization efficiency in aerobic shaking culture of Bacillus sp. ARBI was markedly higher than that in standing culture. At the optimal culture condition, decolorization efficiency by the Bacillus sp. ARBl was 93% after 32 hrs batch culture. In the case of batch culture using real dye processing wastewater, dye decolorization efficiency of Bacillus sp. ARBl was 78% after 40 hrs.

• Microbiology and Biotechnology Letters
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• v.25 no.1
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• pp.30-36
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• 1997

To genetically breed powerful multifunctional antagonistic bacteria, the urease gene of alkalophilic Bacillus pasteurii was transferred into Bacillus subtilis YB-70 which had been selected as a powerful biocontrol agent against root-rotting fungus Fusarium solani. Urease gene was inserted into the HindIII site of pGB215-110 and designated pGU266. The plasmid pGU266 containing urease gene was introduced into the B. subtilis YB-70 by alkali cation transformation system and the urease gene was very stably expressed in the transformant of B. subtilis YB-70(pGU266). The optimal conditions for the transfomation were also evaluated. From the in vitro antibiosis tests against F. solani, the antifungal activity of B. subtilis YB-70 containing urease gene was much efficient than that of the non-transformed strain. Genetic improvement of B. subtilis YB-70 by transfer of urease gene for the efficient control seemed to be responsible for enhanced plant growth and biocontrol efficacy by combining its astibiotic action and ammonia producing ability.