• Applied Biological Chemistry
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• 제50권1호
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• pp.12-17
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• 2007

태백산 토양에서 유화활성과 안정도가 높은 biosurfactant 생산균주 TBM 3101을 분리하여 동정한 결과 B. subtilis로 판명되었다. B. subtilis TBM 3101의 배양액에서 표면장력은 최저 29mN/m까지 감소되었고, 이후 장시간 계속 유지되었다. 또한, tributyrin을 기질로 사용하였을 때 2.68로 가장 큰 유화력을 보였고, 그 외에 soybean oil, crude oil, tetradecane 에서도 비슷한 활성을 보였다. 각종 다른 합성계면활성제의 유화활성 및 안정성을 고려하여 비교 분석한 결과 B. subtilis TBM 3101 생산하는 biosurfactant는 tween류와 span 85와 유사한 유화활성을 나타내었고, tween 80과 triton X-100과 비슷한 유화 안정도를 보여주었다.

• 미생물학회지
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• 제33권4호
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• pp.237-241
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• 1997

Streptomyces coelicolor A3(2) 배양액의 lipase(EC 3.1.1.3)는 ${\alpha}$-naphthyl-butyrate에 대하여 활성을 나타내어 ${\alpha}$-naphthyl-acetate에 활성을 나타내는 esterase와 구분할 수 있었다. Streptomyces coelicolor A3(2) 세포외 lipase를 Sephadex G-100, DEAE-Cellulose 그리고 Phenyl-Sepharose CL4B 크로마토그래피의 과정을 통해 16% 수율로 15배 분리정제 하였다. SDS-폴리아크릴아마이드 겔 전기영동에서는 34.7 kDa정도의 분자량을 갖는 것으로 나타났다. Tributyrin를 기질로 사용하였을 때 이 lipase의 최적활성조건은 pH 8에서 9 그리고 $37^{\circ}C$였다. 기질로서 triacylglycerol의 지방산 길이가 증가할수록 활성은 감소하였다. A-factor에 의해 lipase활성이 억제되므로 배양초기의 낮은 lipase활성과 관련될 것으로 보인다.

• Journal of Plant Biotechnology
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• 제6권1호
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• pp.63-67
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• 2004

A simple procedure for the extraction of the lipolytic enzyme from rice bran has been developed. High activity of lipolytic enzyme was obtained by first defatting the rice bran to remove lipid components with various extraction conditions. Then, after rove cycles of aqueous extraction, rice bran lipolytic enzyme was purified using micro- and ultrafiltration apparatus. Lipolytic enzyme activity was estimated by its hydrolytic action of tributyrin. The result indicated that the standard activity curve of butyric acid showed that the potential rice bran enzyme is a hydrolytic lipase enzyme. In addition, it showed higher lipolytic activity and specific enzyme activity with further purification by micro- and ultrafiltration. The size of rice bran lipase enzyme was identified through 15 ％ SDS-PAGE. The molecular weight of the rice bran lipase enzyme was 41 kDa.

• 한국미생물·생명공학회지
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• 제22권6호
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• pp.599-606
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• 1994

Bacillus stearothermomophilus, a strong xylan degrader, was confirmed to express multiple esterase activities in addition to the major xylanolytic enzymes. One of the genes encoding the esterases was isolated from the genomic library of B. stearothermophilus constructed with EcoRl restriction endonuclease and pBR322 plasmid. Three recombinant plasmids showing the tributyrin degrading activity were selected from approximately 7, 000 E. coli HB101 transformants, and were found to have the same insert of a 3.2 kb DNA fragment. Restriction mapping and hybridization studies revealed that the gene(estII) on the hybrid plasmid (pKMG7) had originated from the B. stearothermophilus chromosome, and was distinct from the estl, another esterase gene of B. stearothermophilus isolated in the previous work. The E. coli cells harboring pKMG7 produced an acetylxylan esterase that exibited similar substrate specificity to the esterase encoded by the estI gene.

• 환경생물
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• 제36권2호
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• pp.199-205
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• 2018

Petroleum energy is the major source of the world energy market, and its massive usage, and the corresponding extreme environmental pollution, imposes a serious threat on the ecological cycles. By screening oil-contaminated soil, we isolated, identified, and characterized a novel strain that represents a considerable diesel-degrading potentiality; the Bacillus aryabhattai DA2 strain is registered in the NCBI with the accession number MG571630, and it possesses an efficient tributyrin-degrading capacity. The optimal condition for diesel degradation by DA2 strain was observed at pH between 7-8 and at the temperature of $30^{\circ}C$. The strain is resistant to salt as well as the antibiotics like ampicillin and streptomycin. These results indicate B. aryabhattai is one of the potential candidates for the remediation of the diesel-contaminated sites.

• 한국미생물·생명공학회지
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• 제21권6호
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• pp.542-548
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• 1993

Bacillus stearothermophilus was shown to express multiple xylanolytic enzymes including acetyl xylan esterase. Genomic DNA of the strain partially digested with HindIII was ligated into the HindIII site of pBR322, and expressed in E. coli HB101 cells in order to clone the gene for acetyl xylan esterase. One transformant among 4000 screened formed a clear zone around its colony on the LB agar supplemented with 1.0% tributyrin. The functional clone harbored the recombinant plasmid pKMG5 with an insert of 5.1kb.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2004년도 추계학술대회
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• pp.299-301
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• 2004

A simple procedure for the extraction of the lipolytic enzyme from rice bran has been developed. High activity of lipolytic enzyme was obtained by first defatting the rice bran to remove lipid components with various extraction conditions. Then, after five cycles of aqueous extraction, rice bran lipolytic enzyme was purified using micro- and ultrafiltration apparatus. Lipolytic enzyme activity was estimated by its hydrolytic action of tributyrin. The result indicated that the standard activity curve of butyric acid showed that the potential rice bran enzyme is a hydrolytic lipase enzyme. In addition, it showed higher lipolytic activity and specific enzyme activity with further purification by micro- and ultrafiltration.

• 한국미생물·생명공학회지
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• 제33권1호
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• pp.29-34
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• 2005

새만금 갯벌로부터 리파제를 생산하는 균주(S3)를 분리하였다. 생리적, 발효적 특성 및 계통분류학적 특성을 통해서 이 분리균이 Psychrobacter속에 속하는 것으로 판명되어서 Psychrobacter sp. S3로 명명하였다 이 균의 온도에 따른 배양특성을 구한 결과, $30^{\circ}C$에서 생장속도가 가장 빨랐으나, 리파제 효소의 활성은 $20^{\circ}C$에서 가장 높았다. S3리파제의 온도에 따른 p-nitrophenyl caproate 분해활성을 측정한 결과, 최적 온도가 $30^{\circ}C$로 판명되었으며 $10^{\circ}C$에서도 최고활성의 $80\%$ 이상의 활성을 유지하였다. 또한, $10-30^{\circ}C$범위에서의 효소활성에너지가 1.5 kcal/mol로 매우 낮게 계산되었다. 이것을 통해 S3 리파제가 전형적인 저온성 효소임이 확인되었다. 이 효소는 최적 pH가 $9.0\~9.5$인 알칼리성 효소로 확인되었다. 여러 길이의 트리글리세리드 기질을 분해할 수 있으며 그 중에서 $C_4,\;C_{14},\; C_{16}$기질을 가장 빠르게 분해하였다. S3리파제를 트리뷰티린-아가로스 젤에 가하여 온도별로 반응시킨 결과, $30^{\circ}C$와 $40^{\circ}C$에서 반응이 빠르게 진행되었으나, $4^{\circ}C$에서도 분해가 진행되었다.

• 생명과학회지
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• 제20권5호
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• pp.662-669
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• 2010

폐식용유에서 지방분해효소를 생산하는 세균을 분리하였고, PIBWIN 세균동정 방법으로 생리 생화학적 특성을 조사하여 확인한 결과 Pseudomonas sp. OME로 동정하였다. 여러 기질로 지방분해효소 생산을 조사한 결과 올리브유에서 6.1 U/ml의 생산력을 나타내었다. 물리적 인자인 배양시간, 온도. pH 및 올리브유와 효모 추출액의 영양인자에 의한 지방분해효소 생산 조건을 조사 하였다. 효소의 분비는 배양시간. 올리브유 와 효모 추출액의 농도에 강한 영향을 받았으며, RSM을 이용한 최적화는 이들 인자를 가지고 조사하였다. RSM을 이용한 지방분해효소 생산은 배양시간. 올리브유와 효모 추출액의 농도가 48 hr, 0.3 g, 및 0.9 ml에서 최적 생산조건을 나타냈다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권4호
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• pp.367-371
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• 2005

About 3,000 bacterial colonies with esterase activities were isolated from soil samples by enrichment culture and halo-size on Luria broth-tributyrin (LT) plates. The colonies were assayed for esterase activity in microtiter plates using enantiomerically pure (R)- and (S)-2-phenylbutyric acid resorufin ester (2PB-O-res) as substrates. Two enantioselective strains (JH2 and JH13) were selected by the ratio of initial rate of hydrolysis of enantiomerically pure (R)- and (S)-2-PB-O-res. When cell pellets were used, both strains showed high apparent enantioselectivity ($E_{app}>100$) for (R)-2PB-O-res and were identified as Exiguobacterium acetylicum. The JH13 strain showed high esterase activity on p-nitrophenyl acetate (pNPA), but showed low lipase activity on p-nitrophenyl palmitate (pNPP). The esterase was located in the soluble fraction of the cell extract. The crude intracellular enzyme preparation was stable at a pH range from 6.0 to 11.0.