• 한국토양비료학회지
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• 제31권3호
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• pp.285-290
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• 1998

화학비료 및 유기물 등의 개량제를 43년간 장기 연용한 논 토양에서 부숙퇴비 시용내력의 지표미생물로 활용할 수 있는 고온성 Bacillus속을 검정하고, 이들 균과 유기물 함량간의 관계를 연구하였다. 고온성 Bacillus 속은 평판 도말법으로 $65^{\circ}C$에서 12시간 이내에 콜로니를 측정할 수 있었으며, 논 토양에 서식하는 고온성 Bacillus속은 퇴비 시용량이 많을 수록 일정하게 증가하고, 토양 유기물 함량과도 $R^2=0.835^{**}$(n=32)의 정의 상관관계를 가졌다.

• 생명과학회지
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• 제8권4호
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• pp.387-394
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• 1998

A thermophilic bacterium (strain DG0303) producing a thermostable $\alpha$-glucosidase was isolated from manure and identified as Bacillus sp. Strain DG0303 produced high level of $\alpha$-glucosidase compared with other thermophilic Bacillus strains. The cellular protein patterns were also compared with other Bacillus strains by sodium dodecyl sulfatepolyacrylamide gel electrophoresis(SDS-PAGE). On the basis of 16S rDNA analysis the Bacillus sp. DG0303 was found to be a member of Bacillus rDNA group 5. The optimum temperature for growth was 65$\circ$C and no growth was obtained at 40$\circ$C or 75$\circ$C. The optimum pH for growth was 5.5 to 8.5. $\alpha$-glucosidase activity was produced during growth and most activity was detected in the culture supernatant. The $\alpha$-glucosidase production was constitutive in the absence of carbohydrates. High level of enzyme activity was detected when the culture was grown on medium containing starch. Addition of glucose resulted in the repression of the $\alpha$-glucosidase production. The optimum pH and tempoerature for enzyme activity were pH 5.0 and 65$\circ$C, respectively. When analyzed by zymogram, the culture supernatant showed a single $\alpha$-glucosidase band with a molecular weight of approximately 60,000.

• 한국미생물·생명공학회지
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• 제17권3호
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• pp.178-182
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• 1989

고온, 호알칼리성 Bacillus K-17 균주에서 한가지 xylanase 유전자를 pBR322를 벡터로 이용하여 클로닝시켰다. Xylan을 함유하는 LB 한천배지에서 분해환을 형성하는 대장균 형질전환주에서 재조합 플라스미드 pAXl13을 분리하였으며, 본 pAXl13 은 pBR322와 고온, 호알칼리성 Bacillus K-17균주 염색체 DNA의 4.3Kb HindIII 절편으로 구성되어 있었다. Biotin으로 표식된 pAXl13을 probe로 하여 상동성시험을 하여 본 결과, pAXl13에 존재하는 4.3Kb Hind III 절편은 고온, 호알칼리성 Bacillus K-17 균주 유래임을 확인하였다. pAXl13 을 가지는 E. coli 균주가 생성하는 xylanase는 균체외에 존재하였으며 그 효소학적 성질은 고온, 호알칼리성 Bacillus K-17 균주의 xylanase I 과 II중에서 xylanase I과 동일하였다.

• 한국미생물·생명공학회지
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• 제23권2호
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• pp.197-202
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• 1995

The conditions for the $\beta$-fructofuranosidase production from alkalophilic, thermophilic Bacillus sp. TA-11 were investigated. The maximal enzyme production was obtained when the strain was cultured at 50$\circ$C for 36 hrs with batch culture in the optimal medium containing 1.0% sucrose, 0.6% yeast extract, 0.1% each of KH$_{2}$PO$_{4}$, K$_{2}$HP0$_{4}$, NaH$_{2}$PO$_{4}$, and initial pH 9.5, and the final enzyme activity under the above condition was 102 units per ml of cell free extract.

• Journal of Microbiology and Biotechnology
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• 제9권5호
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• pp.646-649
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• 1999

A thermophilic bacterium producing D-stereospecific dipeptidase was isolated from Korean soil samples. The enzyme hydrolyzed the peptide bond between D-alanyl-D-alanine (D-Ala-D-Ala). The isolated bacterial strain was rod shaped, gram-positive, motile, and formed an endospore. Morphological and physiological characteristics suggested this microorganism a thermophilic Bacillus species, and was named as Bacillus sp. BCS-l. The production of D-stereospecific dipeptidase was growth-associated and optimal at $55^{\circ}C$. The enzyme was applied for the synthesis of D-amino acid-containing peptide, N-benzyloxycarbonyl-L-aspartyl-D-alanine benzyl ester (Z-L-Asp-D-AlaOBzl), as a model reaction. A thermodynamically controlled synthesis of Z-L-Asp-D-AlaOBzl was achieved in an organic solvent.

• 자연과학논문집
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• 제5권1호
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• pp.47-52
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• 1992

$\beta$-galactosidase를 강력하게 생산하는 호알칼리성, 고온성 세균 TA-11를 부엽토에서 분리하여 Bacillus sp. TA-11로 동정 하였다. Bacillus sp. TA-11에 의한 $\beta$-galactosidase 생산은 lactose 1.5%, peptone과 yeast ext. 각각 0.4%, $MgSO_4$ 0.2%, $NH_4$CL 0.05% 및 NaCl 0.2% 등을 함유한 배지의 pH를 10.0으로 하여 시험균을 접종한후 $50^{\circ}C$에서 2일간 진탕배양 하였을 때 가장 좋았다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.56-59
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• 2000

Thermophilic bacterium, Bacillus stearothermophilus NUB3621, was engineered to produce ethanol from glucose by introducing cloned thermostable pyruvate decarboxylase and alcohol dehydrogenase genes. A novel promoter sequence was screened and used for the enhancement of these two enzymes. Successful redirection of metabolic flux into ethanol was obtained. In addition, gene expression profiling using Bacillus subtilis DNA microarray was analyzed to overcome the intrinsic low glucose utilization of B.stearothermophilus. Many known and unknown genes were identified to be up or down regulated under glucose-containing media.

• 한국미생물·생명공학회지
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• 제25권6호
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• pp.623-629
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• 1997

The studies of isolation and physiological characteristics of mesophilic or thermophilic bacteria from thermophilic oxic process (TOP) treating Chinese restaurant wastes were conducted. Chinese restaurant wastes were consist of moisture; 75.8%, solids; 24.2% and ash; 0.49%. The volatile solid was about 99% of total dry solids. In wastes used in this experiment, there was content of crude protein; 4.47%, crude lipid; 3.56%, free sugar, 0.4% , crude starch; 10.34% and crude fiber 3.14%, respectively. And then it has about 4,970 kcal/kg-dry solid of Chinese restaurant wastes. From TOP treating the chinese restaurant wastes, 37 strains of mesophilic or thermophilic bacteria were primarily isolated using medium used for the isolation and among them 6 strains of thermophilic and 7 strains of mesophilic bacteria were selected by testing the activities of amylase, cellulase, protease and lipase. TB-1, TB-9 as thermophilic bacteria and MB-15-1, 15-2, MB23 as mesophilic bacteria having strong enzyme activity were selected among isolated strains. All selected strains reduced nitrate to nitrite and they utilized glucose, manose, manitol, and maltose as carbon source. From these MB15-2 was identified as Bacillus cereus, TB1, Bacillus licheniformis and TB9; Bacillus schlegelii.

• 한국균학회지
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• 제37권2호
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• pp.150-154
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• 2009

The diversity of microflora according to growth stage of Pleurotus ostreatus and the correlation between microbe and medium fermentation were investigated. In farmhouse I, the aerobic bacteria and fungi as longer of growing period were increased. And, thermophilic bacteria and fluorescent Pseudomonas sp. showed high density at the early stage of spawn inoculation. The thermophilic actinomycetes were distributed evenly during all the growing period, but mesophilic actinomycetes were not observed. In farmhouse II, thermophilic actinomycetes were not observed in fermented medium and density of fungi were suddenly increased at 60 days after spawn inoculation. And also, mushrooms can hardly be harvested due to Penicillium spp. After medium fermentation, density of aerobic bacteria, thermophilic bacteria, and fluorescent Pseudomonas sp. was higher at farmhouse I than those of farmhouse II. In farmhouse I, Bacillus sp. and Pseudomonas sp. dominated at early stage of mushroom growth but as time goes by, density of Bacillus sp. was higher than the others. And also, the kind of microbe showed a few at early stage of mushroom growth but increased as time goes by. In farmhouse II, Bacillus sp. was dominated at early stage of mushroom growth. And the growth of Bacillus sp. and Pseudomonas sp. showed intersect aspect each other in the farmhouse I but Bacillus sp. dominated during all growth periods in the farmhouse II.

• 한국미생물·생명공학회지
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• 제23권3호
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• pp.304-310
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• 1995

A thermophilic bacterium producing the extracellular cellulase-free xylanase was isolated from soil and has been identified as Bacillus sp. The optimal growth temperature was 50$\circ$C and the optimal pH, 7.0. Under the optimal growth condition, maximal xylanase production was 2.2 units/ml in the flask culture. The enzyme production was induced by xylan and xylose, but was repressed by sucrose or trehalose. The partially purified xylanase was most active at 70$\circ$C. It was found that the enzyme was stable at 65$\circ$C for 10 hours with over 75% of the activity. The enzyme was most active at pH 7.0 and retained 90% of its maximum activity between pH 5.0 and pH 9.0 though Bacillus sp. was not grown on alkaline conditions (>pH 8.0). In addition, the activity of xylanase was over 60% at pH 10.0. At the ambient temperature, the enzyme was stable over a pH range of 5.0 to 9.0 for 10 h, indicating that the enzyme is thermostable and alkalotolerant. The activity of xylanase was completely inhibited by metal ions including Hg$^{2+}$ and Fe$^{2+}$, while EDTA, phenylmethylsulfonyl fluoride (PMSF), $\beta$-mercaptoethanol and SDS didn't affect its activity. The enzyme was also identified to exert no activity on carboxymethylcellulose, laminarin, galactomannan, and soluble starch.