• The Plant Pathology Journal
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• 제15권6호
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• pp.319-322
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• 1999

In order to obtain bacterial metabolites inducing disease resistance in pepper plant, two hundred bacterial isolates were isolated from the rhizosphere soil of tobacco, cucumber, and pepper plant. Ethyl acetate extract of each bacterial culture was used to screening for induction of resistance against phytophthora blight of pepper plant. Application of ethyl acetate extract of an isolate SH122 culture to pepper plant conferred resistance against phytophthora blight consistently and significantly. According to cellular fatty acid analysis and other characteristics, the SH122 culture were significantly lower than those on control plants treated with ethyl acetate extract of nutrient broth. The B. pumilus SH122 itself of ethyl acetate extract of its culture did not show antifungal activity against phytophthora blight in pepper plants.

• Journal of Microbiology and Biotechnology
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• 제11권3호
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• pp.534-538
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• 2001

The xynA gene encoding an alikali-tolerant endo-1,4-${\beta}$-xylanase (XYN) was cloned from the alkalophilic Bacillus pumilus A-30. The nucleotide sequence of a 974-bp DNA fragment containing the xynA was determined. An ORF of 684 nucleotides that encoded a protein of 228 amino aicds was detected. Asparagine-71 of XYN from B. Pumilus A-30 showed to be highly conservative in alkaline xylanases of family G/11, upon comparing the amino acid sequences of 17 family G/11 xylanases. Site-directed mutation of N71D of the xynA gene resulted in a decrease of 12.4% in the specific acitivity and a significant decline in the enzyme activity in the alkaline pH range.

• Journal of Microbiology and Biotechnology
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• 제23권9호
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• pp.1221-1228
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• 2013

Two lipase genes (bpl1 and bpl3) from Antarctic Bacillus pumilus strains were expressed in Bacillus subtilis. Both recombinant lipases BPL1 and BPL2 were secreted to the culture medium and their activities reached 3.5 U/ml and 5.0 U/ml, respectively. Their molecular masses apparent using SDS-PAGE were 23 kDa for BPL1 and 19 kDa for BPL3. Both lipases were purified to homogeneity using ammonium sulfate precipitation and HiTrap SP FF column and Superose 12 column chromatographies. The final specific activities were estimated to be 328 U/mg for BPL1 and 310 U/mg for BPL3. Both lipases displayed an optimum temperature of $35^{\circ}C$, similar to other mesophilic enzymes. However, they maintained as much as 70% and 80% of the maximum activities at $10^{\circ}C$. Accordingly, their calculated activation energy at a temperature range of $10-35^{\circ}C$ was 5.32 kcal/mol for BPL1 and 4.26 kcal/mol for BPL3, typical of cold-adapted enzymes. The optimum pH of BPL1 and BPL3 was 8.5 and 8.0, respectively, and they were quite stable at pH 7.0-11.0, showing their strong alkaline tolerance. Both lipases had a preference toward medium chain length ($C_6-C_{10}$) fatty acid substrates. These results indicate the potential for the two Antarctic B. pumilus lipases as catalysts in bioorganic synthesis, food, and detergent industries.

• Journal of Microbiology and Biotechnology
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• 제21권1호
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• pp.20-27
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• 2011

The purification and characterization of a $Mn^{2+}$-dependent alkaline serine protease produced by Bacillus pumilus TMS55 were investigated. The enzyme was purified in three steps: concentrating the crude enzyme using ammonium sulfate precipitation, followed by gel filtration and cation-exchange chromatography. The purified protease had a molecular mass of approximately 35 kDa, was highly active over a broad pH range of 7.0 to 12.0, and remained stable over a pH range of 7.5 to 11.5. The optimum temperature for the enzyme activity was found to be $60^{\circ}C$. PMSF and AEBSF (1 mM) significantly inhibited the protease activity, indicating that the protease is a serine protease. $Mn^{2+}$ ions enhanced the activity and stability of the enzyme. In addition, the purified protease remained stable with oxidants ($H_2O_2$, 2%) and organic solvents (25%), such as benzene, hexane, and toluene. Therefore, these characteristics of the protease and its dehairing ability indicate its potential for a wide range of commercial applications.

• 한국식품위생안전성학회지
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• 제26권1호
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• pp.76-81
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• 2011

The protease produced by a Bacillus pumilus CN8 strain was purified by DEAE-Cellulose-52 ion exchange. It has a molecular weight of approximately 96,920 Dalton. In the present study, this protease showed strong activity over a broad range of pH (6.5-9.5) and temperature from $40^{\circ}C$ to $60^{\circ}C$, and the protease performed the maximal activity at pH 7.3 at $42^{\circ}C$. The effect of metal ions on protease activity showed that $K^+$ could slightly increase the protease activity, and other ions such as $Zn^{2+}$, $Fe^{2+}$, $Na^+$, $Ca^{2+}$, $Mg^{2+}$ had no significant activation or inhibition to the protease (P> 0.05), and the more important is that $Cu^{2+}$, $Mn^{2+}$, $Sn^{2+}$, $Cd^{2+}$ had a strong inhibitory effect on the protease activity.

• The Plant Pathology Journal
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• 제36권3호
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• pp.231-243
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• 2020

Rice blast, caused by Magnaporthe oryzae, is one of the most destructive rice diseases worldwide. The aim of this study was to screen bacterial isolates to efficiently prevent the occurrence of rice blast. A total of 232 bacterial isolates were extracted from nonrhizospheric rice soil and were screened for antifungal activity against M. oryzae using a leaf segment assay. Strains S170 and S9 showed significant antagonistic activity against M. oryzae in vitro and in leaf disk assays, and controlled M. oryzae infection under greenhouse conditions. The results showed that strains S170 and S9 could effectively control rice leaf blast and panicle neck blast after five spray treatments in field. This suggested that the bacterial strains S170 and S9 were valuable and promising for the biocontrol of rice disease caused by M. oryzae. Based on 16S rDNA, and gyrA and gyrB gene sequence analyses, S170 and S9 were identified as Bacillus amyloliquefaciens and B. pumilus, respectively. The research also demonstrated that B. amyloliquefaciens S170 and B. pumilus S9 could colonize rice plants to prevent pathogenic infection and evidently suppressed plant disease caused by 11 other plant pathogenic fungi. This is the first study to demonstrate that B. amyloliquefaciens and B. pumilus isolated from nonrhizospheric rice soil are capable of recolonizing internal rice stem tissues.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1986년도 추계학술대회
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• pp.527.3-527
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• 1986

Several factors predicted to affect the protoplast formation and regeneration were investigated. The optimum lysozyme, casamino acid and PVP concentration were 0.5 (mg/$m\ell$), 0.1 (%) and 1.5(%). In B. pumilus, Penicillin-G treatment concentration was 0.3 (U/$m\ell$) and optimum treatment period was transit log. phase. And in the case of Celm. fimi, 0.3 (U/$m\ell$) and initial log. phase. Osmotic stabilizer and di-cation for OSM medium of B.pumilus and Gelm .fimi were 25mM CaCl2, 0.5M sodium sucinate and 50mM MgCl$_2$, 100mM CaCl$_2$, 0.4M sodium succinate. The regeneration frequency of B.pumilus and Celm. fimi were 14.6(%) and 6.9(%).

• Journal of Microbiology and Biotechnology
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• 제23권5호
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• pp.614-622
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• 2013

Daqu, a traditional fermentation starter, has been used to produce attractively flavored foods such as vinegar and Chinese liquor for thousands of years. Although Bacillus spp. are one of the dominant microorganisms in Daqu, more precise information is needed to reveal why and how Bacillus became dominant in Daqu, and next, to assess the impact of Bacillus sp. on Daqu and its derived products. We combined culture-dependent and culture-independent methods to study the ecology of Bacillus during Daqu incubation. Throughout the incubation, 67 presumptive Bacillus spp. isolates were obtained, 52 of which were confirmed by 16S rDNA sequencing. The identified organisms belonged to 8 Bacillus species: B. licheniformis, B. subtilis, B. amyloliquefaciens, B. cereus, B. circulans, B. megaterium, B. pumilus, and B. anthracis. A primer set specific for Bacillus and related genera was used in a selective PCR study, followed by a nested DGGE PCR targeting the V9 region of the 16S rDNA. Species identified from the PCR-DGGE fingerprints were related to B. licheniformis, B. subtilis, B. amyloliquefaciens, B. pumilus, B. benzoevorans, and B. foraminis. The predominant species was found to be B. licheniformis. Certain B. licheniformis strains exhibited potent antimicrobial activities. The greatest species diversity occurred at the Liangmei stage of Daqu incubation. To date, we lack sufficient knowledge of Bacillus distribution in Daqu. Elucidating the ecology of Bacillus during Daqu incubation would enable the impact of Bacillus on Daqu to be accessed, and the quality and stabilization of Daqu-derived products to be optimized.

• 유기물자원화
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• 제14권4호
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• pp.141-150
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• 2006

음식물류폐기물의 친환경적 처리를 위한 소재를 개발하기 위하여 지렁이로부터 유기물 분해 및 응집능을 갖는 기능성 미생물을 분리하였다. 분리된 균주 중 음식물류폐기물을 처리하는데 적합한 것으로 판단되는 균주를 최종 선별하여 JS-01균주로 명명하였으며 16s rDNA 염기서열분석에 의한 최종결과, Bacillus pumilus로 동정되었다. 0.5% Kaolin clay을 대상으로 JS-01균주의 응집능을 조사한 결과 응집을 위한 최적 생장조건은 MRS 액체배지에서 온도 $37^{\circ}C$ 및 pH 7.0으로 나타났다. 유기물분해능 중에서는 특히, 음식물류폐기물의 대표적 성분인 섬유소에 대한 분해능을 확인하였다. 따라서 JS-01균주는 음식물류폐기물의 친환경적 처리 및 재활용을 위한 미생물 소재 및 음식물 침출수의 효과적인 응집 처리를 위한 생체량 생성에 이용할 수 있을 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제24권4호
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• pp.431-439
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• 2014

We report the construction of two Bacillus subtilis expression vectors, pBNS1/pBNS2. Both vectors are based on the strong promoter P43 and the ampicillin resistance gene expression cassette. Additionally, a fragment with the Shine-Dalgarno sequence and a multiple cloning site (BamHI, SalI, SacI, XhoI, PstI, SphI) were inserted. The coding region for the amyQ (encoding an amylase) signal peptide was fused to the promoter P43 of pBNS1 to construct the secreted expression vector pBNS2. The applicability of vectors was tested by first generating the expression vectors pBNS1-GFP/pBNS2-GFP and then detecting for green fluorescent protein gene expression. Next, the mannanase gene from B. pumilus Nsic-2 was fused to vector pBNS2 and we measured the mannanase activity in the supernatant. The mannanase total enzyme activity was 8.65 U/ml, which was 6 times higher than that of the parent strain. Our work provides a feasible way to achieve an effective transformation system for gene expression in B. subtilis and is the first report to achieve B. pumilus mannanase secretory expression in B. subtilis.