• Korean Journal of Microbiology
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• v.44 no.3
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• pp.258-263
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• 2008

Late blight, one of the most important disease in many agricultural crops, is caused by Phytophthora infestans. Fusarium wilt is a vascular disease of many plants caused by Fusarium oxysporum. Some bacteria isolated from rhizosphere were screened for their ability to inhibit the growth of F. oxysporum and P. infestans. Productions of siderophore, $\beta-1$,3-glucanase, hydrogen cyanide and chitinase by 4 isolated strains were examined. Among them, Bacillus sp. RFO41 most effectively inhibited the growth of F. oxysporum. The highest productions of siderophore and $\beta-l$,3-glucanase were shown in the culture of Bacillus sp. RFO41. Bacillus strain PS2 was most effective against P. infestans. PS2 showed the highest production of chitinase and hydrogen cyanide. A significant relationship was shown between the antagonistic effects of isolates against F. oxysporum and P. infestans and their production level of siderophore, $\beta-1$,3-glucanase, hydrogen cyanide, and chitinase.

• Journal of Microbiology and Biotechnology
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• v.19 no.8
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• pp.818-822
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• 2009

A ${\beta}-1$,3-1,4-glucanase from the fungus Laetiporus sulphureus var. miniatus was purified as a single 26 kDa band by ammonium sulfate precipitation, HiTrap Q HP, and UNO Q ion-exchange chromatography, with a specific activity of 29 U/mg. The molecular mass of the native enzyme was 52 kDa as a dimer by gel filtration. ${\beta}-1$,3-1,4-Glucanase showed optimum activity at pH 4.0 and $75^{\circ}C$. The half-lives of the enzyme at $70^{\circ}C$ and $75^{\circ}C$ were 152 h and 22 h, respectively. The enzyme showed the highest activity for barley ${\beta}$-glucan as ${\beta}-1$,3-1,4-glucan among the tested polysaccharides and p-nitrophenyl-${\beta}$-D-glycosides with a $K_m$, of 0.67 mg/ml, a $k_{cat}$ of 13.5 $S^{-1}$ and a $k_{cat}/K_m$ of 20 mg/ml/s.

• Journal of Microbiology and Biotechnology
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• v.20 no.3
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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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.1
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• pp.19-22
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• 1998

Effects of acute anoxia on carbohydrate hydrolytic enzyme activities and free amino acid contents in malt were examined. Malts were prepared with barley grains germinated for 7 days which contained the highest levels of amylolytic and(1-3,1-4)-$\beta$-glucanase activities. $\alpha$-Amylase and $\beta$-amylase activities in malts were not significantly affected by anoxia for 5 or 10 h.(1-3,1-4)-$\beta$-Glucanase activity, however, decreased about 7 to 10% by anoxia for 5 or 10 h. Alanine and $\gamma$-aminobutyric acid content changed drastically. Alanine contents in malts increased by 2.2- and 2-fold, and $\gamma$-aminobutyric acid contents by 1.4- and 1.9-fold under anoxia for 5 and 10 h, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.3
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• pp.303-307
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• 1996

The degree of autolysis and presence of cell-wall degrading enzymes in an anaerobic ruminal fungus, Piromyces communis OTSI, grown in liquid medium, was monitored to evaluate the effect of self-digestion on fungal biomass. After a 30 days incubation period fungal dry weight decreased by 45% and the cell wall component chitin decreased by 22%. Chitinase activity detected in the supernatant was mainly of the endotype and peaked at day 6 of the incubation. ${\beta}-1$, 3-glucanase was detected from day 4 and increased throughout the incubation period. Autolysis was a slow process, and under natural conditions it is unlikely that it plays a significant role in the degradation of the spent fungal vegetative stage in the rumen.

• Journal of Microbiology and Biotechnology
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• v.17 no.1
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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.

• Korean Journal of Poultry Science
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• v.21 no.3
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• pp.195-205
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• 1994

Effects of the addition of \beta-glucanase to barley-based layer diets were examined by feeding 200 Leghorn layers with corn-based (Control) and \beta-glucanase supplemented diets (Barley+ Enzyme). The results obtained are sumrrarized as follows. 1. There were no siginificant (P>0.05) differences in hen-day egg production(%) and average egg weight between two treatments, indicating that the \beta-glucanase supplemented barley could successfully replace the commonly used corn in the layer diets. 2. Although there was no statistical difference (P>0.05) between two treatments, the daily feed consumption was numerically high in layers fed the barly diet compared to the corn-based diet. 3. Availabilities of crude fat and crude fiber of the barley diet were significantly poor (P<0.05) as compared to corn diet. 4. The \beta-glucarase supplementation depressed the viscosity of barley diets and excreta from therm. 5. Both serum and egg yolk cholesterol were not significantly affected by the addition of \beta-glucarase in the barley based diet. Our data indicate that the barley grain supplemented with \beta-glucarase can be sucessfully used as an energy source of layer diet when there is a price advantage. Although some possibilities to produce low cholesterol egg were recognized in this study, further studies pertaining to long-term feeding experiment and elucidaton of the metabolic interrelationship between serum and yolk cholesterol, are required to confirm the result.

• Journal of Plant Biotechnology
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• v.43 no.4
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• pp.450-456
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• 2016

Rhizoctonia leaf blight (large patch) has become a serious problem in Korean lawn grass, which is extremely hard to treat and develops mostly from the roots of lawn grass to wither it away. Rhizoctonia leaf blight (large patch) is caused by Rhizoctonia solani AG2-2 (IV). To develop zoysia japonica with strong disease tolerance against this pathogenic bacterium, ${\beta}-1,3-glucanase$ was cloned from zoysia japonica, which is one of the PR-Proteins known to play a critical role in plant defense reaction. ${\beta}-1,3-glucanase$ is known to be generated within the cells when plant tissues have a hypersensitive reaction due to virus or bacterium infection and secreted outside the cells to play mainly the function of resistance against pathogenic bacteria in the space between the cells. This study utilized the commonly preserved part in the sequence of corn, wheat, barley, and rice which had been researched for their disease tolerance among the ${\beta}-1,3-glucanase$ monocotyledonous plants. Based on the part, degenerate PCR was performed to find out the sequence and full-length cDNA was cloned. E.coli over-expression was conducted in this study to mass purify target protein and implement in vitro activation measurement and antibacterial test. In addition, to interpret the functions of ZjGlu1 gene, each gene-incorporating plant transformation vectors were produced to make lawn grass transformant. Based on ZjGlu1 protein, antibacterial activity test was conducted on 9 strains. As a result, R. cerealis, F. culmorum, R.solani AG-1 (1B), and T. atroviride were found to have antibacterial activity. The gene-specific expression amount in each organ showed no huge difference in the organs based upon the transformant and against 18s gene expression amount.

• Applied Biological Chemistry
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• v.42 no.4
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• pp.324-329
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• 1999

Barley malts were prepared at 15, 18 and $21^{\circ}C$ for $3{\sim}6$ days, and assayed for ${\beta}-glucanase$, ${\alpha}-amylase$ and ${\beta}-amylase$ activities. ${\beta}-Glucanase$ activity increased markedly during earley germination and reached maximum at the 6th day of germination. ${\beta}-Glucanase$ activity in six-rowed barley malt was much higher than that in two-rowed malt. ${\beta}-Glucanase$ activity was associated with reduction in ${\beta}-glucan$ content during germination. ${\beta}-amylase$ activity was also considerably higher in two-rowed barley, and increased continuously during 6-day germination. ${\beta}-Amylase$ activity was the lowest at $15^{\circ}C$, the highest at $18^{\circ}C$, and intermediate at $21^{\circ}C$ of germination temperature. Considerable amount of ${\beta}-amylase$ was detected in ungerminated raw barley, and this enzymatic activity tended to increase during 6-day germination. Diastatic power, measure of starch-saccharifying enzyme, in six-rowed malt was $1.4{\sim}1.6$ fold higher than in two-rowed malt. Germination at $18^{\circ}C$ for $5{\sim}6$ days was suggested to be the optimum condition for manufacturing good quality malts, in terms of enhanced starch-degrading enzymatic activity.

• Microbiology and Biotechnology Letters
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• v.16 no.2
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• pp.79-84
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• 1988

Dye materials and cross linking agents were used for the determination of $\beta$-glucanase activities. The objective of this study was to prepare the blue coloured substrates which are sensitive, specific and simple for the determination of $\beta$-glucanase in malt and Bacillus subtilis K-4-3 enzymes. This method is based on the principle of measuring colorimetrically the split product of coloured and cross linked substrate. The best coupling of dye stuff of $\beta$-glucan was cibacron blue 3G-A and the colour released can suitably be measured at 623nm. Optimal concentration of dye and cross linking agents was 1.5g and 1.25$m\ell$ under 0.1N NaOH. The sensitivity comparison proved that the stained $\beta$-glucan method is much more sensitive than the DNS method to determine reducing sugar released by the enzyme.