• 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.

• 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.

• 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.

• 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.

• Korean Journal of Microbiology
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• v.25 no.4
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• pp.339-345
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• 1987

A bacterium K-4-3, producing $\beta$-glucan hydrolyzing enzyme, was isolated from soil and identified to be Bacillus subtilis by its morpholohical and physiological characteristics. $\beta$-glucan was coloured using cibacron blue 3G-A and cross linded by the addition of 1, 4-butanedioldiglycidyl ether. This substrate was used for the isolation of $\beta$-glucanase producing microorganism. The $\beta$-glucan hydrolyzing enzyme actibity from isolated K-4-3 strain was also measured using the modified substrate. Bacillus subtilis K-4-3 produced the highest extracellular $\beta$-glucan hydrolyzing activity in the basal medium containing $\beta$-glucan as a carbon source, peptone and tryptone as a nitrogen source, and magnesium sulfate as an inorganic salt. The optimum temperature and initial pH for $\beta$-glucanase production by Bacillus subtilis K-4-3 were $37^{\circ}C$ and pH6. The highest enzyme activity was obtained at the culture age of 54 hrs with rotary shaking at $37^{\circ}C$. The crude enzyme showed the highest activity at pH 7.5-8.0 and $65^{\circ}C$.

• Journal of Microbiology and Biotechnology
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• v.16 no.7
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• pp.1132-1138
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• 2006

Three types of xylanases (EC 3.2.1.8) were detected in the strain Aspergillus niger A-25, one of which, designated as XynIII, also displayed ${\beta}-(l,3-1,4)-glucanase$ (EC 3.2.1.73) activity, as determined by a zymogram analysis. XynIII was purified by ultrafiltration and ion-exchange chromatography methods. Its apparent molecular weight was about 27.9 kDa, as estimated by SDS-PAGE. The purified XynIII could hydrolyze birchwood xylan, oat spelt xylan, lichenin, and barley ${\beta}-glucan$, but not CMC, avicel cellulose, or soluble starch under the assay conditions in this study. The xylanase and ${\beta}-(l,3-1,4)-glucanase$ activities of XynIII both had a similar optimal pH and pH stability, as well as a similar optimal temperature and temperature stability. Moreover, the effects of metal ions on the two enzymatic activities were also similar. The overall hydrolytic rates of XynIII in different mixtures of xylan and lichenin coincided with those calculated using the Michaelis-Menten model when assuming the two substrates were competing for the same active site in the enzyme. Accordingly, the results indicated that XynIII is a novel bifunctional enzyme and its xylanase and ${\beta}-(l,3-1,4)-glucanase$ activities are catalyzed by the same active center.

• 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.

• 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 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.

• The Korean Journal of Soil Zoology
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• v.8 no.1_2
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• pp.7-12
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• 2003

Endogeneous endoglucanase (EC 3.2.1.4) cDNA was cloned from a representative species (Eisenia anderi) of the earthworm family Lumbricidae. Endoglucanase from the midgut of the earthworm is composed of 456 amino acids and belongs to glycosyl hydrolase family 9 (GHF9), sharing high homologies (50-51 %) with those of selected termite and crayfish. This endoglucanase consists of three consensus catalytic domains found in most microbial cellulases. A phylogenetic tree was constructed using the amino acid squence data matched through the BLASTX program and showed that GHF9 families could be divided into four groups of arthropoda, bacteria, plant and annelida.