• Journal of Microbiology and Biotechnology
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• v.16 no.6
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• pp.921-926
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• 2006

The production and location of xylanolytic enzymes in alkaliphilic Bacillus sp. K-1, isolated from the wastewater treatment plant of the pulp and paper industry, was studied. When grown in alkaline xylan medium, the bacteria produced xylanolytic enzymes such as xylanase, $\beta$-xylosidase, arabinofuranosidase, and acetyl esterase. Two types of xylanases (23 and 45 kDa) were found to be extracellular, but another type of xylanase (35 and/or 40 kDa) was detected as pellet-bound that was eluted with 2% triethylamine from the residual xylan of the culture. The xylanases were different in their molecular weight and xylan-binding ability. Arabinofuranosidase and $\beta$-xylosidase were found to be intracellular and extracellular, respectively, and acetyl esterase was found to be extracellular. The extracellular xylanolytic enzymes effectively hydrolyzed insoluble xylan, lignocellulosic materials, and xylans in kraft pulps.

• Journal of Life Science
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• v.13 no.5
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• pp.618-625
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• 2003

Investigations were carried out to optimize the culture conditions for the production of xylanase by Paenibacillus sp. DG-22, a moderately thermophilic bacterium isolated from timber yard soil. Xylanase production showed a cell growth associated profile. Xylanase activity was found only in the culture supernatant, while $\beta-xylosidase$ activity was mainly associated with the cells. The formation of xylanase activity was induced by xylan and repressed by glucose and xylose. The production profile of xylanase was examined with various commercial xylan and maximum yield was achieved with 0.1∼ 0.5% birchwood xylan. Among various nitrogen sources tested, yeast extract was optimal for the production of xylanase. The xylanase activity was inhibited by $Co^{2+},\; Cu^{2+},\; Fe^{3+},\; Hg^{2+}\;$ and$\;Mn^{2+}$ ions while $Ca^{2+},\; Mg^{2+},\; Ni^{2+},\; Zn^{2+}$ions and DTT stimulated xylanase activity Mercury (II) ion at 5 mM concentration abolished all the xylanase activity. The predominant products of xylan-hydrolysate were xylobiose, xylotriose, and higher xylooligo-saccharides, indicating that the enzyme was an endoxylanase.

• Journal of the Korean Wood Science and Technology
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• v.19 no.2
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• pp.22-29
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• 1991

The endo-1,4-${\beta}$-xylanase was extracted and purified from the extracellular xylanolytic systems of Trichoderma viride. The crude enzyme was chromatographed with ion-exchange reins of DEAE Sepharose CL-6B, Sepharose, S-Sepharose CL-6B and the resulting xylanase was turned out to be a single protein as 20KD hy SDS-polyacrylamide gel electrophoresis. The xylooligomers were obtained from xylan by incubation with the purified xylanase up to 50%. The ${\beta}$-xylosidase lost its activity completely by incubation of crude enzyme for 24hr with buffer solution of pH 2.8 at $27^{\circ}C$. And also, the xylooligomers were obtained from xylan as a main product by incubation with the crude enzyme treated with acidic buffer.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.371-374
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• 2005

In our previous work in transcriptional regulation of sugar, expression of genes encoding putative glycosyl hydrolases in Arabidopsis was induced by sugar starvation. They were annotated as b-galactosidase (At5g56870), ${\beta}-xylosidase$ (At5g49360) and ${\beta}-glucosidase$ (At3g60140), which belong to glycosyl hydrolase family that has a catalytic domain of polysaccharides. From the primary structure of deduced amino acid sequence, they were predicted to localize to cell wall. Further investigation of these cell wall hydrolases implicated that cell wall polysaccharides provide metabolizable sugars to nutrient allocation under sugar starvation.

• Journal of the Korean Wood Science and Technology
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• v.35 no.6
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• pp.91-99
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• 2007

Activities of the extracellular enzyme from Fomitopsis palustris, a brown-rot fungi, and by which crystallinity changes of cellulose in the various softwoods, such as Larix leptolepsis, Finns rigida, Finns koraiensis and Finns densiflora by liquid culture, were investigated. Activity of Cellobiohydrolase (CBH) from F. palustris was detected in the every test softwoods culture, showing activities of the Endoglucanase (EG), $\beta$-glucosidase (BGL) and $\beta$-1,4-xylosidase (BXL). It was shown high enzyme activities in the sapwood culture than heartwood of the same wood species, However, the enzyme activities in most of test wood cultures increased with longer incubation time, indicating a possibility of intermix sapwood and heartwood for degradation process by enzyme. Also it was shown that protein patterns of the extracellular enzyme from F. palustris in wood particle substrate of the several domestic softwoods were similar with each other wood species, which suggested the possibility of mixing all softwoods in saccharification by enzyme from F. palustris. Crystallinity reduction value of cellulose by F. palustris was 4.2~20.4% in 4 weeks cultivation, 12.9~28.9% in 8 weeks.

• Korean Journal of Ecology and Environment
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• v.39 no.4 s.118
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• pp.435-444
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• 2006

A suite of extracellular enzyme activities involved in organic carbon decomposition were determined in three northern peatlands (a bog, a fen, and a swamp) over a 12 month period along with trace gas ($CO_2$ and $N_2O$) flux and DOC dynamics in the wetlands. The activities varied $0.008-0.066\;{\mu}mole\;g^{-1}\;min^{-1}$, $0.003-0.021\;{\mu}mole\;g^{-1}\;min^{-1}$, $0.003-0.016\;{\mu}mole\;g^{-1}\;min^{-1}$, $0.004-0.047\;{\mu}mole\;g^{-1}\;min^{-1}$, for ${\beta}-glucosidase$, cellobiohydrolase, ${\beta}-xylosidase$, and N-acetylglucosaminidase, respectively. In general, the activities were highest in the forested swamp followed by the fen and the bog. When the data from three wetlands are combined, the enzyme activities exhibited significant positive correlations with trace gas emission and available carbon. Further, the average activity of 4 enzymes explained about 20-40% of the variations of trace gas emssion and available carbon. The results indicate that enzymes related to the mineralization of organic carbon may play an important role in trace gas flux and DOC dynamics in northern peatlands.

• The Korean Journal of Mycology
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• v.41 no.3
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• pp.160-166
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• 2013

Recovery of ${\alpha}$-amylase (EC 3.2.1.1), lignin peroxidase (EC 1.11.1.14), laccase (EC 1.10.3.2), xylanase (EC 3.2.1.8), ${\beta}$-xylosidase (EC 3.2.1.37), ${\beta}$-glucosidase (EC 3.2.1.21) and cellulase (EC 3.2.1.4) from spent mushroom composts (SMCs) of Pleurotus cornucopiae, Pleurotus ostreatus, Pleurotus eryngii, Hericium erinaceum, Lyophyllum ulmarium, Agrocybe cylindracea, Lentinus lepideus, and Flammulina velvtipes were investigated using different extraction buffers. The maximum recovery of the enzymes was mostly detected in SMC extracts with tap water and 0.25% Triton X-100 by shaking incubation (200 rpm) for 2 h at $4^{\circ}C$. The xylanase (152 U/g) and laccase (8.1 U/g) activities were the highest in SMC extracts from F. velvtipes and P. eryngii. In addition, high enzymatic activities of ${\alpha}$-amylase (3.6 U/g) and cellulase (3.4 U/g) was detected in SMC extract of A. cylindracea. Futhermore, cellulase and laccase activities of SMCE from P. eryngii were compared to commercial enzymes.

• Journal of the Korean Wood Science and Technology
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• v.38 no.5
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• pp.421-428
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• 2010

This study investigated on enzyme production in the digestive organs of the native termite (Reticulitermes speratus) in Milyang, Korea. Four types of major cellulases [EG (endo-1,4-${\beta}$-glucanase), BGL (${\beta}$-glucosidase), CBH (cellobiohydrolase) and BXL (${\beta}$-1,4-xylosidase)] were present in the digestive organs of the termite. The strong enzyme activity for BGL was found from the native termite, and also shown that the enzyme was distributed in the salivary gland, foregut, and hindgut. BXL, which breaks down hemicellulose near the amorphous region, was detected mainly from salivary gland, foregut, and midgut. However, CBH was distributed mainly in the hindgut. Meanwhile, EG which degrades cellulose, was found mainly in the hindgut and salivary glands. These facts indicate that celluases production patterns are differ from different sites compare to the same species found in Japan, suggesting that enzyme production in the digestive organs of termites is changed according to their habitats.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.5
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• pp.382-390
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• 2006

Various microorganisms were isolated from the surface waters and sediments of eutrophic lakes and reservoirs in Korea to enable an investigation of bacteria having algal lytic activities against Anabaena flos-aquae when water blooming occurs and to study enzyme profiles of algal lytic bacteria. Two bacterial strains, AFK-07 and AFK-13, were cultured, characterized and identified as Acinetobacter johnsonii and Sinorhizobium sp., respectively. The A. johnsonii AFK-07 exhibited a high level of degradatory activities against A. flos-aquae, and produced alginase, caseinase, lipase, fucodian hydrolase, and laminarinase. Moreover, many kinds of glycosidase, such as ${\beta}-galactosidase,\;{\beta}-glucosidase,\;{\beta}-glucosaminidase,\;and\; {\beta}-xylosidase$, which hydrolyzed ${\beta}-O-glycosidic$ bonds, were found in cell-free extracts of A. johnsonii AFK-07. Other glycosidases such as ${\alpha}-galactosidase,\;{\alpha}-N-Ac-galactosidase,\;{\alpha}-mannosidase,\; and\;{\alpha}-L-fucosidase$, which cleave ${\alpha}-O-glycosidic$ bonds, were not identified in AFK-07. In the Sinorhizobium sp. AFK-13, the enzymes alginase, amylase, proteinase (caseinase and gelatinase), carboxymethyl-cellulase (CMCase), laminarinase, and lipase were notable. No glycosidase was produced in the AFK-13 strain. Therefore, the enzyme system of A. johnsonii AFK-07 had a more complex mechanism in place to degrade the cyanobacteria cell walls than did the enzyme system of Sinorhizobium sp. AFK-13. The polysaccharides or the peptidoglycans of A. flos-aquae may be hydrolyzed and metabolized to a range of easily utilized monosaccharides or other low molecular weight organic substances by strain AFK-07 of. A. johnsonii, while the products of polysaccharide degradation or peptidoglycans were more likely to be utilized by Sinorhizobium sp. AFK-13. These bacterial interactions may offer an alternative effective approach to controlling the water choking effects of summer blooms affecting our lakes and reservoirs.

• Journal of Microbiology and Biotechnology
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• v.32 no.2
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• pp.187-194
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• 2022

Two α-ʟ-arabinofuranosidases (BfdABF1 and BfdABF3) and a β-ᴅ-xylosidase (BfdXYL2) genes were cloned from Bifidobacterium dentium ATCC 27679, and functionally expressed in E. coli BL21(DE3). BfdABF1 showed the highest activity in 50 mM sodium acetate buffer at pH 5.0 and 25℃. This exo-enzyme could hydrolyze p-nitrophenyl arabinofuranoside, arabino-oligosaccharides (AOS), arabinoxylo-oligosaccharides (AXOS) such as 3²-α-ʟ-arabinofuranosyl-xylobiose (A³X), and 2³-α-ʟ-arabinofuranosyl-xylotriose (A²XX), whereas hardly hydrolyzed polymeric substrates such as debranched arabinan and arabinoxylans. BfdABF1 is a typical exo-ABF with the higher specific activity on the oligomeric substrates than the polymers. It prefers to α-(1,2)-ʟ-arabinofuranosidic linkages compared to α-(1,3)-linkages. Especially, BfdABF1 could slowly hydrolyze 2³,3³-di-α-ʟ-arabinofuranosyl-xylotriose (A²⁺³XX). Meanwhile, BfdABF3 showed the highest activity in sodium acetate at pH 6.0 and 50℃, and it has the exclusively high activities on AXOS such as A³X and A²XX. BfdABF3 mainly catalyzes the removal of ʟ-arabinose side chains from various AXOS. BfdXYL2 exhibited the highest activity in sodium citrate at pH 5.0 and 55℃, and it specifically hydrolyzed p-nitrophenyl xylopyranoside and xylo-oligosaccharides (XOS). Also, BfdXYL2 could slowly hydrolyze AOS and AXOS such as A³X. Based on the detailed hydrolytic modes of action of three exo-hydrolases (BfdABF1, BfdABF3, and BfdXYL2) from Bf. dentium, their probable roles in the hemiceullose-utilization system of Bf. dentium are proposed in the present study. These intracellular exo-hydrolases can synergistically produce ʟ-arabinose and ᴅ-xylose from various AOS, XOS, and AXOS.