• 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.

• 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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• 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.

• 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.

• 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.

• 한국식품영양학회지
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• 제15권2호
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• pp.126-130
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• 2002

고온성이며 호알칼리성인 Bacillus sp. TA-11이 생성하는 Invertase의 생합성 조절 기작을 규명하고자 먼저 이들의 유도와 억제에 관하여 검토하였다. Invertase는 10mM sucrose을 함유한 생합성 조절배지에서 3시간에 효율적으로 유도되었고 glucose는 sucrose에 의한 invertase 유도를 inducer exclusion 방식으로 억제시켰다. CAMP의 첨가로 glucose에 의한 catabolic repression이 다소 줄어들었다.

• 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.

• 한국식품영양학회지
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• 제9권4호
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• pp.447-451
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• 1996

Bacillus sp. TA-11에 대한 오골계 난백 lysozyme과 일반 난백 lysozyme의 용균성을 비교분석 하였다. 오골계 난백 lysozyme의 용균활성은 Bacillus sp. TA-11를 5$0^{\circ}C$에서 18시간 정치배양한 대수기 후기의 세포에 대하여 가장 높았고, lysozyme의 농도는 0.25%가 최적이었다. 또한 lysozyme의 최적반응 pH와 온도는 각각 4.5와 35$^{\circ}C$였다. 일반 난백 lysozyme의 용균활성은 시험균주를 24시간 배양한 정지기의 세포에 대하여 가장 높았고 lysozyme의 최적 농도는 0.5%였으며 반응 최적 pH와 온도는 각각 5.5와 4$0^{\circ}C$이었다.

• 생명과학회지
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• 제21권10호
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• pp.1481-1486
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• 2011

버섯 생산 후 발생되는 부산물인 팽이버섯 수확 후 배지로부터 7종의 고온성 균주를 분리하였으며 이 중 곰팡이독소를 생성하는 Asp. flavus와 Asp. ochraceous에 대한 항균활성이 높으면서 xylanase와 cellulase 생성능이 우수한 균주를 최종 선발하여 UJ03으로 명명하였다. Bacillus ID kit와 VITEK 2 system를 이용하여 분리균 UJ03의 생리적 생화학적 특성을 조사한 결과 분리균 UJ03은 Bacillus 속과 유사한 특징을 나타내었으며 16S rDNA 염기서열 분석 결과에서는 B. amyloliquefaciens와 98.9%의 상동성을 나타내었다. 이와 같은 결과를 종합하여 분리균 UJ03은 Bacillus sp. UJ03으로 동정되었으며 분리균 UJ03이 생성하는 항균물질은 TLC와 HPLC 분석에서 Bacillus 속 균주가 생성하는 펩타이드성 항균물질인 iturin A와 유사한 특성을 나타내었다.

• 환경위생공학
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• 제5권2호
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• pp.103-110
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• 1990

For production of thermophilic and alkaline protease, Bacillus sp. strain AP-5 was isolated from a compost. The production of the protease was reached at maximum for 4 days at $55^{\circ}$ in standing culture. Chitin and Cellulose as carbon source, and Skim Milk as nitrogen source were favorable for the production of the enzyme. Optimal temperature and optimal pH of the enzyme was $55^{\circ}$ and 11, respectively. Metal ion didn't effect on the enzyme activity, the protease was very stable at heat treatment of 30 min at $55^{\circ}$.