• 한국작물학회:학술대회논문집
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• 한국작물학회 1992년도 춘계 학술대회지
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• pp.20-21
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• 1992

• Applied Biological Chemistry
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• 제35권3호
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• pp.165-169
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• 1992

녹맥아로부터 $endo-{\beta}-1,3-glucanase$를 추출하여 각종 수지로써 정제하여 glucanase I과 glucanase II의 존재를 확인하였고, 정제한 두 효소의 특성에 대하여 실험한 결과, 두 정제 효소의 분자량은 각각 35,000과 28,000으로 추정되었으며 최적 pH는 5.5이었고 pH 안정 범위는 각각 달랐다. 두 정제효소의 최적 온도는 glucanase I, II 다 같이 $40^{\circ}C$이었으며 glucanase I에 비해 glucanase II가 열에 다소 안정하였다. 그리고 $AgNO_3$와 $HgCl_2$와 같은 화합물은 효소활성을 저해하였다. Laminarin을 기질로 하여 측정한 Km값은 glucanase I, II 각각 1.03 mg/ml, 1.20 mg/ml이었다.

• 미생물학회지
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• 제38권4호
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• pp.241-246
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• 2002

Bacillus circulans의 endo-$\beta$-1,3-1,4-glucanase유전자를 발현 vector pQE30에 삽입시키고 E. coli Ml5에서 발현시켜 효소를 생산.정제하였다. 생산된 endo-$\beta$-1,3-1,4-glucanase는 nickel-nitrilotriacetic acid (Ni-NTA) metal-affinity chromatography 과정을 거쳐 단일 단백질로 정제되었다. 정제된 효소의 분자량은 SDS-PAGE 전기영동법으로는 28 kDa이었다. 효소 최적 활성 pH와 온도는 각각 pH 6.8과 $60^{\circ}C$였다. 이 효소는 pH 5.5～7.5와$55^{\circ}C$ 이하의 온도에서 안정하였다. 또한 본 효소는 여러 가지 금속 이온에 의해 대부분의 활성이 억제되었고, 특히 $Hg^{2+}$에서는 강하게 효소 활성이 저해됨을 보였다. 유기 용매에 대한 활성은 10%의 methanol이나 ethanol, isopropanol, 1-butanol 에 대하여 모두 낮은 활성을 나타내었다.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1986년도 추계학술대회
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• pp.520.1-520
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• 1986

Endo-$\beta$-1,3-glucanase는 barley glucan, laminarin등에 특이적으로 작용하는 효소로서 Malting process, Brewing process에 중요한 효소이다. 본 연구에서는 산업적으로 이용하기 위한 기초자료를 얻기 위하여 국산맥주맥으로 발아한 Green Malt를 Sample로 하여 Endo-$\beta$-1,3-glucanase를 추출하여 (DEAE Sephadex A-50, CM sephadex C- 50 Sephadex G-75)등을 이용하여 정제하여 이들 정제효소의 효소학적 성질등을 검토하였다.

• 미생물학회지
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• 제42권1호
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• pp.67-72
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• 2006

클로닝된 Bacillus circulans ATCC21367 유래 cellulolytic xylanase 유전자(bglBC2)의 염기서열을 결정 분석하였다. 본 유전자는 1,224 bp의 407개 아미노산을 암호하는 open reading frame (ORF)으로 구성되어 있었으며 염기서열로부터 산출된 유전자의 분자량은 45 kDa으로 효소의 SDS-PAGE로부터 측정된 분자량과 일치하였다. ATG 개시 코돈의 9bp 위쪽에 Shine-Dalgarno (SD) 서열로 추정되는 5'-AAAGGAG-3' 서열이 확인되었고 그 상단에 promoter로 추정되는 -35 서열(TTTACA)과 -10 서열(TATACT)이 위치하고 있었으며, 이는 B. subtilis promoter consensus sequence와 유사하였다. 한편, 이 효소의 아미노산 서열은 이미 보고된 B. circulans KSM-N257의 alkaline $endo-\beta-1,4-glucanase$와는 97%, B. circulans WL-12의 $endo-\beta-1,3-1,4-glucanase$와는 75%, Bacillus sp. KSM-330의 $endo-\beta-1,4-glucanase$ (cellulase)와는 45%의 유사성을 나타내었다. 또한 bglBCS 염기서 열의 정보를 GenBank에 등록하였으며 등록번호는 Ar269256이다.

• Journal of Microbiology and Biotechnology
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• 제20권3호
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• pp.467-473
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• 2010

To improve the expression efficiency of recombinant endo-$\beta$-1,4-glucanase in P. pastoris, the endo-$\beta$-1,4-glucanase (egI) gene from Aspergillus niger was synthesized using optimized codons. Fourteen pairs of oligonucleotides with 15 bp overlap were designed and the full-length syn-egI gene was generated by two-step PCR-based DNA synthesis. In the synthesized endo-$\beta$-1,4-glucanase gene syn-egI, 193 nucleotides were changed, and the G+C content was decreased from 54% to 44.2%. The syn-egI gene was inserted into pPIC9K and transformed into P. pastoris GS115 by electroporation. The enzyme activity of recombinant P. pastoris stain 2-7# reached 20.3 U/ml with 1% barley $\beta$-glucan and 3.3 U/ml with 1% carboxymethylcellulose (CMC) as substrates in shake flasks versus 1,270.3 U/ml and 220.7 U/ml for the same substrates in 50-1 fermentors. The molecular mass of the recombinant protein was approximately 40 kDa as determined by SDS-PAGE analysis, the optimal temperature for recombinant enzyme activity was $70^{\circ}C$, and the optimal pH was 5.0 when CMC was used as the substrate.

• 한국미생물·생명공학회지
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• 제23권6호
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• pp.652-658
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• 1995

We attempted simultaneous expression of genes coding for endoglucanase and $\beta $-glucosidase from Pseudomonas sp. by using a synthetic two-cistron svstem in Escherichia coli and Saccharomyces cerevisiae. Two-cistron system, 5'--tac promoter-endoglucanase gene--$\beta $-glucosidase gene-- 3', 5'-tac promoter--$\beta $-glucosidase gene--endoglucanase gene--3' and 5'-tac promoter--endoglucanase gene--SD sequence--$\beta $-glucosidase gene--3, were constructed, and expressed in E. coli and S. cerevisiae. The E. coli and S. cerevisiae contained two-cistron system produced simultaneously endoglucanase and $\beta $-glucosidase. The recombinant genes contained the bacterial signal peptide sequence produced low level of endoglucanase and $\beta $-glucosidase in S. cerevisiae transformants: Approximately above 44% of two enzymes was localized in the intracellular fraction. The production of endoglucanase and $\beta $-glucosidase in veast was not repressed in the presence of glucose or cellobiose. The veast strain contained recombinant DNA with two genes hydrolyzed carboxvmethyl cellulose, and these endoglucanase and $\beta $-glucosidase degraded CMC synergistically to glucose, cellobiose and oligosaccharide. This result suggests the possibility of the direct bioconversion of cellulose to ethanol by the recombinant yeast.

• Journal of Microbiology and Biotechnology
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• 제17권1호
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• pp.58-66
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• 2007

Isolation, expression, and characterization of a novel $endo-{\beta}-1,3(4)-D-glucanase$ with high specific activity and homology to Bacillus lichenases is described. One clone was screened from a genomic library of Paenibacillus sp. F-40, using lichenan-containing plates. The nucleotide sequence of the clone contains an ORF consisting of 717 nucleotides, encoding a ${\beta}-glucanase$ protein of 238 amino acids and 26 residues of a putative signal peptide at its N-terminus. The amino acid sequence showed the highest similarity of 87% to other ${\beta}-1,3-1,4-glucanases$ of Bacillus. The gene fragment Bg1 containing the mature glucanase protein was expressed in Pichia pastoris at high expression level in a 3-1 high-cell-density fermenter. The purified recombinant enzyme Bg1 showed activity against barley ${\beta}-glucan$, lichenan, and laminarin. The gene encodes an $endo-{\beta}-1,3(4)-D-glucanase$ (E. C. 3.2.1.6). When lichenan was used as substrate, the optimal pH was 6.5, and the optimal temperature was $60^{\circ}C$. The $K_m,\;V_{max},\;and\;k_{cat}$ values for lichenan are 2.96mg/ml, $6,951{\mu}mol/min{\cdot}mg,\;and\;3,131s^{-1}$, respectively. For barley ${\beta}-glucan$ the values are 3.73mg/ml, $8,939{\mu}mol/min{\cdot}mg,\;and\;4,026s^{-1}$, respectively. The recombinant Bg1 had resistance to pepsin and trypsin. Other features of recombinant Bg1 including temperature and pH stability, and sensitivity to some metal ions and chemical reagents were also characterized.

• 한국토양동물학회지
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• 제8권1_2호
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• pp.7-12
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• 2003

지렁이 (Eisenia andrei)의 중장에서 내생의 endoglucanase 유전자의 전체 염기 서열을 동정하였다. ORF의 길이는 1,371 bp이며, 456개의 아미노산으로 번역된다. NCBI에 등록된 가재와 흰개미의 cellulase 및 endo-$\beta$-1, 4-glucanase와 50-51%의 유사성을 보이며, 활성 부위가 잘 보존되어 있었다. 계통수 분석에서는 다른 동물 분류군에서 밝혀진 GHF9 그룹의 cellulase와 근연관계가 없음이 확인되었다.

• Journal of Microbiology and Biotechnology
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• 제11권2호
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• pp.229-233
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• 2001

Trichoderma reesei Rut C-30 produced high levels of ${\beta}$-glucosidase, endo-${\beta}$-glucosidase, endo-${\beta}$-1,4-glucanase, and exo-${\beta}$-1,4-glucanase. In pilot-scale production (50-1 fermentor), productivity and yield of CMCase (carborymethyl cellulose) and FPase (filter paper activity) were 273 U/ml and 35 U/ml, and 162 FPU/l.h and 437 FPU/g, respectively. The fed-batch techniques were used to improve enzyme activities with constant cell concentration. The acidity was an important parameter and controlled at pH 3.9 and 5.0 by automatic addition of ammonium hydroxide. Cellulase powder was prepared by ammonium sulfate precipitation and its CMCase and FPase activities were 3,631 U/g and 407 U/g, respectively.