• 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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• 제8권2호
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• pp.141-145
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• 1998

Overproduction of intracellular ${\beta}$-glucosidase was attempted by modifying the promoter region of a ${\beta}$-glucosidase gene cloned from Cellulomonas fimi and expressing it in Bacillus subtilis DB 104. A strong engineered promoter, BJ27UΔ88, was fused to the ${\beta}$-glucosidase gene after removing its native promoter. An effective Shine-Dalgamo sequence (genel0 of phage T7) was inserted between the promoter and the ${\beta}$-glucosidase structural gene. The modified gene was overexpressed in B. subtilis and produced 1121.5 units of ${\beta}$-glucosidase per mg protein which is about $12\%$ of total intracellular protein. Secretion of overproduced intracellular ${\beta}$-glucosidase was attempted by using the signal sequence of the Bacillus endoglucanase gene as well as an in-frame hybrid protein of endoglucanase. The hybrid protein was normally secreted into the culture medium and still retained ${\beta}$-glucosidase activity.

• Journal of Microbiology and Biotechnology
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• 제6권4호
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• pp.255-259
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• 1996

$\beta$-Glucosidase was known to be involved in the mutagenic activation of $\beta$-glucosides. The level of $\beta$-glucosidase in the feces of adults was 2.7 times higher than that of infants. There was no difference in the percentage of $\beta$-glucosidase positive strains among Bifidobacterium isolates between adults and infants, corresponding to 90 and 92$%$, respectively. However, the strains from adults showed 1.9 times higher enzyme activity than those from infants when grown in Brain Heart Infusion medium. $\beta$-Glucosidase negative strains could not ferment $\beta$-glucosidase substrates, such as cellobiose, salicin, naringin, esculin and arbutin. Presence of $\beta$-glucosidase in Bifidobacterium did not alter the degree of growth in reconstituted skim milk. The $\beta$-glucosidase level was much lower in milk and vegetable medium, although cells grew above $10^8$cfu/ml, than in BHI medium. This study suggests that metabolic activation of the $\beta$-glucosides by Bifidobacterium $\beta$-glucosidase varies significantly depending on types of growth medium.

• 한국미생물·생명공학회지
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• 제20권6호
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• pp.647-654
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• 1992

장내 세균의 생리적 연구를 목적으로 한국인의 장내 상재균을 분리하여 효소 pattern을 관찰하였다. 분리된 Bifidobacterium sp. Int-57은 다른 장내 균종에 비하여 $\alpha$-glucosidase, $\beta$-glucosidase, $\alpha$-galactosidase, $\beta$-galactosidase, $\beta$-xylosidase, $\alpha$-arabinofuranosidase역가가 높았다. Bifidobacterium sp. Int-57의 각 효소 생산에 미치는 탄소원의 영향을 조사하였다. $\alpha$-glucosidase는 maltose, $\beta$-glucosidase는 cellobiose, $\alpha$-galactosidase는 raffinose, 는 lactose, $\beta$-xylosidase와 $\alpha$-arabinofuranosidase는 xyloserk 각각 최적의 탄소원이었다. 또한 각 효소들의 최적 조건과 pH 안정성을 조사 하였다. $\alpha$-glucosidase는 pH 6.0 $40^{\circ}C$에서 $\beta$-glucosidasessm pH 7.0 50에서, $\beta$-galactosidase는 pH 7.0 50에서, $\beta$-xylosidase는 pH 6.0 $40^{\circ}C$에서, $\alpha$-arabinofurnaosidase는 pH 5.0 $50^{\circ}C$에서 각각 최적이었다. $\alpha$-glucosidase는 pH 4.0~9.0 $\beta$-glucosidase는 pH 4.0~7.0 $\beta$-galactosidase는 pH 4.0~9.0, $\beta$-xylosidase는 pH 4.0~6.0, $\alpha$-arabinofuranosidase는 pH 7.0~9.0에서 각각 안정하였다.

• 산업식품공학
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• 제14권3호
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• pp.243-248
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• 2010

${\beta}$-Glucosidase 효소활성이 높은 균주를 선발하기 위하여 다양한 김치에서 분리된 젖산균의 ${\beta}$-glucosidase 활성을 탐색하였다. 김치에서 분리된 156개의 젖산균 중 134개의 균주만이 cellobiose를 탄소원으로 대사하였으며, 세포내 ${\beta}$-glucosidase 활성이 세포외 활성보다 현저히 높았다. 배추김치에서 분리된 W. cibaria KFRI88010 균주가 3.7${\pm}$0.5 unit/mg protein으로서 가장 높은 세포내 ${\beta}$-glucosidase 효소활성을 나타내었으며, 효소활성은 pH 5, ${37^{\circ}C}$ 반응조건에서 가장 높게 나타났다. $Mn^{2+}$를 비롯한 금속이온은 효소활성을 크게 저해하였다. W. cibaria KFRI88010 균주를 배양할 때 사용한 탄소원 중, fructose는 cellobiose나 glucose와 비교하여 약 2.5배 이상의 높은 세포내 ${\beta}$-glucosidase 효소활성을 나타내었다.

• 자연과학논문집
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• 제8권2호
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• pp.57-61
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• 1996

Cellulomonas fimi에서 유래한 $\beta$-glucosidase 유전자를 갖고 있는 대장균으로부터 $\beta$-glucosidase 효소를 정제하였다. 전기 영동과 크로마토그라피 실험을 수행함으로써 정제된 효소의 분자량은 56,000 달톤이며 단일 폴리펩티드로 구성되어 있음을 알 수 있었다. 정제된 $\beta$-glucosidase 효소는 당이 $\beta$-결합을 하고 있는 cellobiose, PNPG, PNPC 등의 기질에 대하여 작용하여 분해시킬 수 있었으나, $\alpha$-결합을 갖고있는 maltose는 분해할 수 없었으므로, $\beta$-결합에 대한 기질 특이성을 갖고 있음을 알았다. 철, 수은, 구리 등의 중금속 이온들에 의해 효소 활성이 저해되었고 DTT에 의해 효소의 활성이 활성화됨을 보임으로써 $\beta$-glucosidase 효소의 활성화 부위는 -SH 기가 중요하게 작용하고 있음을 시사하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제22권2호
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• pp.260-266
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• 2009

The effects of ${\beta}$-glucosidase on the overall growth performance and a set of physiological parameters of broilers were investigated. 240 male, one-day old Avine broiler chickswere randomly allocated to four treatment groups and fed with a corn-soybean meal supplemented with 0% (control), 0.2%, 0.4% and 0.6% ${\beta}$-glucosidase. The 0.2% ${\beta}$-glucosidase group, but not the 0.4% and 0.6% ${\beta}$-glucosidase groups, showed a significantly increased average daily weight gain (p<0.05) over that of the control. All three ${\beta}$-glucosidase feed groups showed significantly higher feed conversion ratios than the control group (p<0.05). Feed supplementation of 0.2% ${\beta}$-glucosidase significantly raised the contents of serum isoflavone aglycones as shown by decreases of genistin and daizin (p<0.01) and an increase of daidzein (p<0.01). The 0.2% ${\beta}$-glucosidase feeding significantly increased the intestinal amylase activity while it had little effect on lipase and trypsin activities (p>0.05). 0.2% ${\beta}$-glucosidase feeding also significant elevated the levels of highdensity lipoprotein cholesterol and malate dehydrogenase while lowering the level of low-density lipoprotein cholesterol (LDL-C). Finally, ${\beta}$-glucosidase improved the anti-oxidative activities of the animals; the 0.2% ${\beta}$-glucosidase feed group had higher activities of superoxide dismutase (p<0.05), glutathione peroxidase and glutathione reductase in the liver (p<0.05), and malondialdehyde level in the serum (p<0.05).

• Journal of Microbiology and Biotechnology
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• 제12권6호
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• pp.895-900
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• 2002

A soil microorganism producing ${\alpha}$- and ${\beta}$-glucosidase inhibitors was identified as Bacillus lentimorbus, based on the fatty acid and morphological analyses, along with biochemical and physiological tests. The ${\alpha}$-glucosidase inhibitor was highly produced by this strain in a culture medium containing $0.25\%$ of sodium glutamate and $0.5\%$ of glucose, pH 8.0 at $30^{\circ}C$ for 2 days. The ${\alpha}$-glucosidase inhibitor from culture filtrate of his strain was identified as water soluble, organic solvent nonextractable, and heat stable. In addition to ${\alpha}$-glucosidase inhibitor, this strain also produced ${\beta}$-glucosidase inhibitor in he same culture medium and this inhibitor showed an antifugal activity against Botrytis cinerea. While the production of ${\alpha}$- glucosidase inhibitor was decreased by a glucose concentration higher than $1\%$, the production of ${\beta}$-glucosidase inhibitor was lot Influenced by a glucose concentration higher than $20\%$. The ${\alpha}$-glucosidase inhibitor from culture filtrate of this strain was separated from the ${\beta}$-glucosidase inhibitor through Sephadex G-100 column chromatography.

• 한국미생물·생명공학회지
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• 제16권2호
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• pp.119-125
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• 1988

Cellulomonas sp. CS1-1 생성의 $\beta$-glucosidase는 cell-bound 효소이었으며, Avicelase와 Carboxymethyl-cellulase (CMCase)는 extracellular 효소로 존재함을 확인하였다. Cellobiose나 CMC 최소배지에서의 균의 생장은 cellobiose보다 glucose 첨가시에 현저히 증가하였다. Cellobiose나 CMC 최소배지에서의 $\beta$-glucosidase 생합성은 glucose 첨가로 현저히 억제되었으나, CMC 최소배지에 cellobiose를 첨가하였을 경우, glucose에 의한 억제 효과와는 반대로, 효소의 생성은 오히려 촉진되었다. 그 외의 탄소원에 관한 영향을 조사한 결과 CMC, 전분, maltose 등의 첨가도 glycerol, arabinose, xylose, trehalose의 첨가시 보다 효소의 생성이 증가되었다. 이상의 결과로 $\beta$-glucosidase 생합성은 glucose에 의하여 catabolite repression을 받았으며, cellobiose, CMC, starch등은 다른 당류보다 효소생성을 현저히 유도하였으므로, 이 효소는 inducible enzyme임을 알 수 있었다. 효소생성에 미치는 질소원을 조사한 결과는 yeast extract가 peptone이나 ammonium sulfate보다 효소생성을 증가시켰다. 효소의 특성을 조사한 결과, 50mM MgCl$_2$가 포함된 10mM potassium phosphate buffer (pH 7.0)에서 효소의 역가가 증가하였고, 최적 pH는 6.0이었고 최적온도는 42$^{\circ}C$ 이었다. p-nitrophenyl-$\beta$-D-glucoside의 농도에 대한 glucose의 Km값은 0.265mM 이었고 $\beta$-D(+)-glucose에 대한 Ki값은 9.0 mM 이었다.

• 미생물학회지
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• 제23권2호
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• pp.77-83
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• 1985

Sophorose에 의한 섬유소분해효소의 유도현상에 있어, Nisizawa등고 Strernbergdh Mandels가 연구보고한 상호 다른 결과들을 재규명하고, sophorose에 의한 섬유소분해효소 합성에 미치는 몇가지 요인들을 조사하고자 본 연구를 행하였다. Sophorose는 Trichoderma reesei QM914에서 CMCase와 ${\beta}-glucosidase$의 합성을 동시에 유도하며, CMCase는 pH 3.0~4.0의 완충용액을 갖는 유도배지에서, ${\beta}-glucosidase$는 pH 5.0~6.0의 K-citrate 완충용액을 갖는 유도배지에서 그 합성이 최대로 유도되었다. 또한, 세포내 ${\beta}-glucosidase$는 pH 6.5의 기질용액에 대하여, 세포의 ${\beta}-glucosidase$는 pH 5.0의 기질용액에 대하여, 각각 최대 활성도를 나타내었다. Methyl ${\beta} D glucosidase$ 는 ${\beta}-glucosidase$의 진정한 유도물질이 아닌 것으로 밝혀졌다. 포도당은 sophorose 에 의한 섬유소분해효소의 유도과정을 억제하며, 이 억제효과는 cAMP의 첨가에 의해서 영향을 받지 아니하였다.