• Journal of Microbiology and Biotechnology
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• 제20권5호
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• pp.889-892
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• 2010

We investigated a potential for glucose production from cellulose material using two kinds of hyperthermophilic enzymes, endocellulase (EG) and beta-glucosidase (BGL). Two BGLs, from hyperthermophile Pyrococcus furiosus and mesophile Aspergillus aculeatus, were compared with P. horikoshii endocellulase (EGPh) for complete hydrolysis of cellulose. The combination reactions by each BGL enzyme and EGPh could produce only glucose without the other oligosaccharides from phosphoric acid swollen Avicel (PSA). The combination of both the hyperthermophilic cellulases, BGLPf and EGPh, will be adaptable to a high efficiency system to produce glucose at high temperature.

• Plant Resources
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• 제8권3호
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• pp.175-180
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• 2005

Thin sections of cellulose fibers were incubated with an endo- and an exoglucanase labeled with gold particles of differing sizes. The hydrolytic sites were then visualized under transmission electron microscopy (TEM). The potential interaction between the ${\beta}$-1, 4-glucan substrates and the endo- and the exoglucanases was investigated using cellulosic and lignocellulosic substrates. The simultaneous visualization was very successful in distinguishing preferred substrates for each cellulase in lignocellulosic substrates. When plant lignocellulose was preincubated with endocellulase, density of the gold labeling greatly increased suggesting that preliminary exposure of lignocellulosic material to endocellulase may have enhanced the accessibility of the substrate to endocellulase and exocellulase. This result provided a plausible explanation for the observed endo/exo cellulase co-hydrolysis.

• 한국당과학회:학술대회논문집
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• 한국당과학회 2006년도 제1회 연례학술대회
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• pp.31-31
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• 2006

• Journal of Microbiology and Biotechnology
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• 제21권3호
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• pp.284-292
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• 2011

An endocellulase-free multienzyme complex was produced by a thermophilic anaerobic bacterium, Thermoanaerobacterium thermosaccharolyticum strain NOI-1, when grown on xylan. The temperature and pH optima for growth were $60^{\circ}C$ and 6.0, respectively. The bacterial cells were found to adhere to insoluble xylan and Avicel. A scanning electron microscopy analysis showed the adhesion of xylan to the cells. An endocellulase-free multienzyme complex was isolated from the crude enzyme of strain NOI-1 by affinity purification on cellulose and Sephacryl S-300 gel filtration. The molecular mass of the multienzyme complex was estimated to be about 1,200 kDa. The multienzyme complex showed one protein on native PAGE, one xylanase on a native zymogram, 21 proteins on SDS-PAGE, and 5 xylanases on a SDS zymogram. The multienzyme complex consisted of xylanase, ${\beta}$-xylosidase, ${\alpha}$-L-arabinofuranosidase, ${\beta}$-glucosidase, and cellobiohydrolase. The multienzyme complex was effective in hydrolyzing xylan and corn hulls. This is the first report of an endocellulase-free multienzyme complex produced by a thermophilic anaerobic bacterium, T. thermosaccharolyticum strain NOI-1.

• 산업기술연구
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• 제29권A호
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• pp.161-167
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• 2009

The bifunctional Xylanase-Cellulase hybrid protein was constructed by gene fusion. Two genes corresponding to endoxylanase gene (xylS) and endocellulase gene (celA) were amplified by PCR from Bacillus licleniformis NBL420. It was then linked through splicing by overlap extension (SOE) by PCR method. The two resulting fused hybrids, xyl/cel and cel/xyl, which differ by its orientation, were confirmed by its nucleotide sequencings. One of two fusion genes, xyl/cel was successfully expressed into pET22b(+) vector (pxyl/cel) with bifunctional xylanase-cellulase activity. On the contrary, the other cel/xyl fusion protein showed only cellulase activity with much decreased xylanase activity. Enzymatic properties of Xyl/Cel fusion protein were investigated regarding optimum pH, optimum temp, thermostability, and pH stability. It was revealed that Xyl/Cel fusion protein retained the bifunctional xylanase-cellulase activities eventhough two enzymes were connected with each other directly. These informations could be useful for construction of other hybrid proteins as well as increased range of substrate utilization.

• 한국미생물·생명공학회지
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• 제18권6호
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• pp.633-639
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• 1990

Cellulase 복합체와 xylanase를 동시에 분비하는 Pseudomonas sp. LBC 505와 CYC 10의 cellulase 유전자를 pUC19를 사용하여 E.coli에 클로닝시켰다. Congo red 염색시 노란색 환을 형성하는 대장균 형질전환에서 7.0Kb-와 4.6Kb-HindIII 단편을 함유한 재조합 플라스미드 pLC1과 pLC2를 가각 분리하였다. DNA hybridization 실험에서 pLC1 과 pLC2는 Pseudomonas sp. LBC 505와 CYC 10 유래임이 각각 밝혀졌고, Immunoassay 실험에서도 유사성이 인정되었다. pLC1을 함유하고 있는 대장균은 cellulas의 24를 세포외로 분비하였고, 효소활성은 모균주에 비해 1.4배 증가하였다. pLC1과 pLC2의 효소학적 성질도 모균주와 동일하였으며, 기질특이성과 HPLC로 유리당을 분석한 결과, 클로닝된 유전자는 endo type인 것으로 나타났다.