• Journal of Life Science
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• v.17 no.3 s.83
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• pp.407-411
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• 2007

Regulation of ${\beta}-xylosidase$ synthesis in Paenibacillus sp. DC-22 was studied to optimize the enzyme production. ${\beta}-Xylosidase$ synthesis of the Paenibacillus sp. DG-22 was observed to be regulated by carbon sources present in culture media. The synthesis of ${\beta}-xylosidase$ was induced by xylan and methyl ${\beta}-D-xylopyranoside$ (${\beta}MeXyl$) but slightly repressed by readily metabolizable monosaccharides. ${\beta}MeXyl$ was found to be the best substrate for the induction of ${\beta}$-xylosidase and the most effective induction was obtained at a concentration of 10 mg/ml. ${\beta}-Xylosidase$ production showed a cell growth associated profile with the maximum amount formed during the late exponential phase of growth. The presence of glucose and xylose decreased the level of ${\beta}-xylosidase$ activity indicating that its production was subjected to a form of carbon catabolite repression. SDS-PAGE and zymogram techniques demonstrated the induction by ${\beta}MeXyl$ and revealed the presence of one ${\beta}-xylosidase$ of approximately 80 kDa.

• Microbiology and Biotechnology Letters
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• v.20 no.5
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• pp.543-550
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• 1992

The production of xylanase and $\beta$-xylosidase was investigated in submerged culture of Aspergillus niger NRC 107. The maximum production occurred when the pH was controlled at 6.0 during the fermentation. Among the various carbon sources investigated, corn-cob xylan (1.5%, w/v) yielded maximal production of the enzymes. The $NaNO_{3}$ was the most favorable nitrogen source for enzyme production and $KH_2P0_4$ concentration at 0.3%(w/v) was found to be optimum. Incorporation of wheat bran to the culture medium improved xylanase production. Addition of L( -) sorbose to the culture medium promoted the secretion of $\beta$-xylosidase. It was possible to increase the production of xylanase (39.43 units/ml) and that of $\beta$-xylosidase (4.2 unitslml) by submerged culturing the A. niger NRC 107 in the modified medium.

• Korean Journal of Food Science and Technology
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• v.25 no.2
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• pp.89-93
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• 1993

In order to study the effect of the intestinal bacteria on the physiology of the human large intestinal tract, we isolated the intestinal bacteria of Koreans and tested the enzymatic patterns. Isolated Bifidobacterium sp. Int-57 showed the higher activity of ${\beta}-xylosidase$ than other intestinal microorganisms. The effect of the carbon sources, nitrogen sources, inorganic salts, initial pH and initial temperature on the production of ${\beta}-xylosidase$ of Bifidobacterium sp. Int-57 was investigated. The most suitable carbon source, nitrogen source and inorganic salt for the production of ${\beta}-xylosidase$ were 1.1% xylose, 0.4% yeast extract and 0.0003% $CoCl_2$ respectively at initial pH 7.0 and temperature $40^{\circ}C$.

• Journal of Microbiology and Biotechnology
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• v.6 no.3
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• pp.173-178
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• 1996

Synergic effects among endo-xylanase, $\beta$-xylosidase, and acetyl xylan esterase of Bacillus stearothermophilus in the hydrolysis of xylan were studied by using birchwood, oat spelt, and acetylated xylan as substrates. Synergism between endo-xylanase and $\beta$-xylosidase was observed on all three substrates tested, indicating that $\beta$-xylosidase enhanced the production of xylose by relieving the end-product inhibition upon endo-xylanase conferred by xylooligomers. Endo-xylanase and $\beta$-xylosidase also showed synergism with acetyl xylan esterase in the hydrolysis of birchwood and acetylated xylan, while no synergic effect was detected in oat spelt xylan hydrolysis. Thus, the hydrolysis of xylan containing acetic acid side chains required the action of acetyl xylan esterase, which eliminated the steric hindrance of the side chains, leading to the better hydrolysis by endo-xylanase and $\beta$-xylosidase , and the acetyl xylan esterase activity was also enhanced by endo-xylanase and $\beta$-xylosidase for the latter enzymes provided acetyl xylan esterase with shorter xylan oligomers, the better substrate for the enzyme.

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.574-579
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• 1989

Chromosomal DNA fragments of Bacillus sp. YA-14, isolated from soil as a potent $\beta$-xylosidase producing bacterium, were ligated to a vector plasmid pBR322 and used to transfer Escherichia coli HB101 cells. The recombinant plasmid pYXL22 was found to enable the transformants to produce $\beta$-xylosidase. pYXL22 was found to contain the 7.0 kb HindIII DNA fragment originated from the Bacillus sp. YA-14 chromosomal DNA by Southern hybridization. The optimum temperature for the reaction of $\beta$-xylosidase produced by E. coli HB101 (pYXL22) was appeared at 3$0^{\circ}C$. The enzyme was maintained stably up to 4$0^{\circ}C$ when stored 1hr at 4$0^{\circ}C$. The $\beta$-xylosidase was repressed completely by 0.4% (w/v) glucose concentration in E. coli HB101 (pYXL22). The optimum concentration of xylose for the $\beta$-xylosidase production in Bacillus sp. YA-14 was 0.2% (w/v).

• Korean Journal of Food Science and Technology
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• v.43 no.2
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• pp.169-175
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• 2011

The ${\beta}$-xylosidase (EC 3.2.1.37) production capabilities of lactic acid bacteria in the genus Leuconostoc, isolated from a variety of kimchi (fermented vegetables), were examined. The intracellular levels of ${\beta}$-xylosidase were similar to the extracellular levels, when most Leuconostoc lactic acid bacteria were grown in a medium containing xylose as the carbon source. Intracellular ${\beta}$-xylosidase with a maximum activity of $1.2{\pm}0.1units/mL$ (mean${\pm}$standard error) was obtained from Leuconostoc lactis KCTC 13344, which was isolated from fermented Chinese cabbage. The optimum reaction conditions for Leu. lactis KCTC 13344 ${\beta}$-xylosidase activity were pH 6.0 and $30^{\circ}C$, and the addition of most divalent cations, except zinc, to the reaction mixture resulted in a slight increase in enzyme activity. Compared with a media containing other carbon sources, the ${\beta}$-xylosidase activity was 5 times higher when Leu. lactis KCTC 13344 was grown in a medium containing xylose as carbon source. Zymographic analysis indicated that the synthesis of Leu. lactis KCTC 13344 ${\beta}$-xylosidase (approximate size, 64 kDa) is induced by xylose. A maximum intracellular ${\beta}$-xylosidase activity of $7.1{\pm}0.3units/mL$ was obtained in a batch cultivation in an MRS medium containing 30 g/L xylose.

• Microbiology and Biotechnology Letters
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• v.20 no.6
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• pp.647-654
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• 1992

In order to study the physiological properties of the intestinal bacteria, we isolated the intestinal bacteria of Koreans and tested the enzymatic patterns. Isolated Bifidobacterium sp. Int-57 had the higher activity of $\alpha$-glucosidase, $\beta$-glucosidase, $\alpha$-galactosidase, $\beta$-galactosidase. $\beta$-xylosidase and $\alpha$-arabinofuranosidase than other intestinal microorganisms. The effect of the carbon sources on the production of each enzymes of Bijidobacterium sp. Int-57 was investigated. The most suitable carbon source for the production of $\beta$-glucosidase was maltose, for a-glucosidase cellobiose, for $\alpha$-galactosidase raffinose, for $\beta$-galactosidase lactose, and for $\beta$-xylosidase and $\alpha$-arabinofuranosidase xylose, respectively. In addition, we investigated the optimal conditions and pH stability of each crude enzymes. The optimal condition of a-glucosidase was pH 6.0 and $40^{\circ}C$. that of Jj-glucosidase pH 7.0 and 50oe, that of $\beta$-galactosidase pH 7.0 and $50^{\circ}C$, that of $\beta$-xylosidase pH 6.0 and $40^{\circ}C$ , and that of $\alpha$-arabinofuranosidase pH 5.0 and $50^{\circ}C$. respectively. a-Glucosidase was stable at pH 4.0-9.0. Jj-glucosidase at pH 4.0-7.0. $\beta$-galactosidase at pH 4.0-9.0, $\beta$-xylosidase at pH 4.0-6.0, and /3-arabinofuranosidase at pH 7.0-9.0, respectively.

• Journal of Microbiology and Biotechnology
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• v.1 no.1
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• pp.17-21
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• 1991

A gene coding for ${\beta}-xylosidase$ in alkalophilic Bacillus sp. YC-335 isolated from soil was cloned into Escherichia coli HB101 using plasmid pBR322. The recombinant plasmid pYK40 was isolated, and the cloned HindIII fragment was 15 kilobases (kb). To reduce the size of the inserted DNA fragment of pYK40, the 15 kb HindIII fragment was subjected to a series of subclonings. A 6 kb subfragment was found to code for ${\beta}-xylosidase$ activity, and the recombinant plasmid was named pYK44. Southern hybridization analysis revealed that the cloned gene hybridized with 3.5 kb, 1.5 kb, and 1.0 kb of HindIII cleaved chromosomal DNA from Bacillus sp. YC-335. ${\beta}-xylosidase$ activity produced by recombinant E. coli was found to be 11 times higher than that produced by Bacillus sp. YC-335. Xylan was required to induce the production of ${\beta}-xylosidase$ in Bacillus sp. YC-335.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.467-470
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• 2003

The endoxylanase (642 bp; 213 amino acids) and ${\beta}-xylosidase$ (1,602 bp; 533 amino acids) genes from Bacillus sp. were amplified by PCR and separately inserted downstream of the yeast ADH1 promoters, resulting in the pAEDX-1 and pAEX plasmid. When the yeast transformants, S. cerevisiae SEY2102 harboring pAEDX-1 or pAEX, were grown on YPD medium, the total activities of the enzymes reached about 9.8 unit/mL for endoxylanase and 2.9 unit/mL for ${\beta}-xylosidase$. When the three kinds of xylan from oat spelts, birch wood, and corncob were hydrolyzed by treatment of recombinant endoxylanase and ${\beta}-xylosidase$, it was found that xylose, xylobiose and xylotriose were produced and xylose was the major product after 12 h reaction. In addition, with the higher amount of enzymes, the more amount of xylose was produced.

• Journal of Microbiology and Biotechnology
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• v.4 no.1
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• pp.49-55
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• 1994

A fungal strain capable of producing extracellular cellulase was isolated from farmland. It was identified as Aspergillus niger, and named Aspergillus niger KKS. Production of cellulase and xylanase by the A. niger KKS was studied through a shake-flask culture. The effects of culture conditions such as inoculum size, temperature, pH, and medium composition on the cellulase and xylanase production were examined. The optimum temperature and pH for the enzyme production were $30^{\circ}C$ and pH 7.0, respectively. The optimized medium was composed of 2.0% (w/v) rice straw, 0.5% (w/v) proteose peptone, 0.5% (w/v) $KH_2 PO_4$, 0.05% (w/v) yeast extract, 0.01% (w/v) $CoSO_4 \cdot 7H_2O$, and 0.05% (w/v) $CuSO$_4$\cdot 5H_2O$. When the strain was incubated with the optimized medium, it gave the activities of endoglucanase, $\beta$-glucosidase, $\beta$-xylosidase, xylanase were 3.80, 4.20, 4.00, 80.0 (IU/mL), respectively. Filter paper and cotton activities were 0.68 and 0.045 (IU/mL), respectively. The results of this study show that A. niger KKS is a potential organism with a wide spectrum of enzyme activities, such as those of $\beta$-glucosidase, $\beta$-xylosidase, and xylanase.