• 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.

• Korean Journal of Microbiology
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• v.42 no.1
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• pp.67-72
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• 2006

The nucleotide sequence of the cloned cellulolytic xylanase gene (bglBC2) from B. circulans ATCC21367 was determined. bglBC2 consists of an 1,224 bp open reading frame (ORF) coding for a polypeptide of 407 amino acids with a deduced molecular weight of 45 kDa. The Shine-Dalgarno (SD) sequence (5'-AAAGGAG-3') was found 9 bp upstream of the initiation codon, ATG. A promoter region corresponding closely to the B. subtilis consensus sequence (-35: TTGACA,-10: TATAAT) was detected, the putative -35 and -10 sequences of which were TTTACA and TATACT, respectively. The deduced amino acid sequence of the cellulolytic xylanase showed 97% homology with that of the alkaline $endo-\beta-1,4-glucanase$ from B. circulans KSM-N257, 75% homology with that of the $endo-\beta-1,3-1,4-glucanase$ from B. circulans WL-12, and 45% homology with that of the $endo-\beta-1,4-glucanase$ (cellulase) from Bacillus sp. KSM-330. The bglBC2 sequence was deposited in Gen-Bank under the accession number AY269256.

• 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.

• Applied Biological Chemistry
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• v.37 no.1
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• pp.43-48
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• 1994

A basic inducible protein, ICG, containing chitinase and ${\beta}-1,3-glucanase$ activity concomittantly was purified from cell suspension culture media of rice after the treatment of chitooligosaccharides. The isolated ICG enzyme gave a single band on native and SDS polyacrylamide gel electrophoresis and its molecular weight was estimated to be 52.53 kd. The optimal temperature and optimal pH of both enzyme activities in ICG were $60^{\circ}C$, pH 6.0 for chitinase activity and $37^{\circ}C$, pH 4.0 for ${\beta}-1,3-glucanase$ activity. $K_M$ and $V_{max}$ values for chitinase were 0.474 mM. 2.997 nM/min., and those for ${\beta}-1,3-glucanase$ were 1.004 mM 0.739 nM/min. respectively. TLC analysis of the chitooligosaccharide hydrolysates with ICG enzyme indicated that ICG acts as endochitinase.

• Korean journal of food and cookery science
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• v.15 no.3
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• pp.238-243
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• 1999

For the development of technique for isolation of naked barley starch from Youngsan variety, optimum conditions of the isolation process were investigated. The effect of blending was examined and the results showed that 29.7% starch yield was obtained by 6 times of blending. After the blending, the barley starch contained 3.2% protein, 0.7% fat, 0.4% fiber, 0.4% ash and 2.8% ${eta}$-glucan. The opitmum conditions of ${eta}$-glucanase treatment were studied and the results showed that the amount of ${eta}$-glucanase and barley flour-water ratio were 60,000 unit and 1/2, the optimum steeping temperature, pH were $45^{\circ}C$ and 6.5, respectively. The effect of alkali treatment which would be supposed to increase the yield and purity of the barley starch was also examined. 76.7% starch content was obtained by 2 hr of alkali treatment. After all the treatment of isolation process, the barley starch finally contained 0.2% protein and 0.1% ${eta}$-glucan.

• 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.

• 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.

• 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.

• Applied Biological Chemistry
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• v.29 no.3
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• pp.266-272
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• 1986

The contents of water soluble ${\beta}-glucan$ were $1.4{\sim}4.0%$ in grains of 4 recommended varieties, and $0.3{\sim}0.6%$ in their malt. The ${\beta}-glucan$ content was subject to environmental factors such as cultivating region and nitrogen fertilizer level. The ${\beta}-glucan$ content of grains was positively correlated with the viscosity, but negatively with the protein and total gum contents. The ${\beta}-glucanase$ activity was $11.0{\sim}20.0$ sec as the reduced flow time in malt of 4 recommended varieties and was also subject to environmental factors. ${\beta}-Glucanase$ activity showed the highest level after the 6th day during malting. The ${\beta}-glucanase$ activity in malt was positively correlated with malt extract, but negatively with the residual ${\beta}-glucan$ content. The protein content in malt was negatively correlated with malt extract, but positively with the diastatic power.

• Microbiology and Biotechnology Letters
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• v.23 no.6
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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.