• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.529-532
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• 2006

Recently the production of ethanol from lignocecllulosics has received much attention due to immense potential for conversion of renewable biometerials into biofuels and chemicals. Fomitopsis palustris causes a typycal brown-rot and is unusual in that it rapidly depolymerize the cellulose in wood without removing the surrounding lignin that normally prevents microbial attack. This study demonstrated that the brown rot basidiomycete F. palustris was able to degrade crystalline cellulose. This fungus could also produce the three major cellulases (BGL, EXG and EG) when the cells were grown on 2.0% Avicel. The fungus was able to degrade both the crystalline and amorphous forms of cellulose from woody biomasses. Moreover, we found that this fungus has the processive EG like CBH which are able to degrade the crystalline region of cellulose. To establish the cellulase system in relation with degradation of woody biomass, we performed that purification, characterization and molecular cloning of a BGL, EGs and GLA from F. palustris grown on Avicel.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1979.10a
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• pp.243.3-244
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• 1979

Low molecular weight endo-glucanase fraction of cellulase from Trichoderma reesei was purified using Sephadex G-100 and concanavalin A-Sepha-rose 4B affinity chromatography. Its biochemical characteristics including pH profile, temperature profile and kinetic behavior were studied. The optimum conditions for enzymatic reaction were pH 6.0 and $5^{\circ}C.$ The activation energy for CMC (carboxymethylcellulose) was 10,800 cal/mole. Its adsorption to amorhous and crystalline cellulose was observed. Adsorption to amorphous cellulose was more rapid and greater than that of crystalline cellulose. Reconstitution study was performed. Significance of low molecular weight endo-glucanase on cellulose hydrolysis will be further discussed.

• Applied Biological Chemistry
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• v.24 no.3
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• pp.186-193
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• 1981

Three fractions of carboxymethyl-cellulase (F-I, F-II, and F-III) and ${\beta}-glucosidase$ form Aspergillus niger were partially purified by ammonium sulfate fractionation. Sephadex G-150 and DEAE-Sephadex column chromatography. The optimum conditions such as pH and temperature and thermal inactivation properties of the enzymes were investigated. Arrhenius plots of F-II and F-III appeared as straight lines, whereas that of F-I was biphasic. The Z-values of F-II and F-III were $8^{\circ}C$ and $10^{\circ}C$ respectively, while that of F-I was $4^{\circ}C$ over $60{\sim}70^{\circ}C$ and $383^{\circ}C$ over $70{\sim}98^{\circ}C$. Three fractions and the crude extract of carboxymethyl-cellulase exhibited a similar optimum pH 4.3 and temperature of $60^{\circ}C$, while Z-value of crude extract $(21.5^{\circ}C)$ was much higher than that of the purified enzyme. Maximum activity of both purified and crude extract of ${\beta}-glucosidase$ was shown at pH 4.7 and $60^{\circ}C$, and z-value of the enzyme was $7^{\circ}C$.

• Korean Journal of Microbiology
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• v.14 no.2
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• pp.84-94
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• 1976

Cellulase components, CMCase(Cx) and Avicelase$(C_1)$, were partially prueified, from the culture extract of a strain of Trichoderma koningii by column chromatography on DEAE-Sephadex A-50 and the step of gel filtration through Sphadex G-150, Optimum pH of CMCase was 5.2 and Avicelase showed the highest activity at pH 5.6 in acetate buffer. Optimal temperatures for activities of CMCase and Avicelase were $50^{\circ}C\;and\;60^{\circ}C, $ respectively. More than 70% of the activities of two enzymes were remained after heating at $60^{\circ}C$ for 30 min and Avicelase is more stable than any other fungal enzymes. The Michaelis constants, Km, of CMCase and Avicelase were 0.116% of CMC and 0.281% of avicel. And also the values of maximum velocity, Vmax, of CMCase and Avicelase were $23.20{\mu}g\;and\;2.54{\mu}g$ of reducing sugar per min. Of the metal ions tested against the activites of CMCase and Avicelase, $Cu^{++}, \; Hg^{++}, \;and\;Pb^{{++}$ are remarkably effective inhibitors. The molecular weights of Cx and $C_1$ component were estimated to be about 47, 000 and 61, 000 by gel filtration method.

• Journal of Microbiology and Biotechnology
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• v.31 no.5
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• pp.740-746
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• 2021

Efficient cellulolytic enzyme production is important for the development of lignocellulose-degrading enzyme mixtures. However, purification of cellulases from their native hosts is time- and labor-consuming. In this study, a constitutive expression system was developed in Penicillium oxalicum for the secreted production of proteins. Using a constitutive polyubiquitin gene promoter and cultivating with glucose as the sole carbon source, nine cellulolytic enzymes of different origins with relatively high purity were produced within 48 h. When supplemented to a commercial cellulase preparation, cellobiohydrolase I from P. funiculosum and cellobiohydrolase II from Talaromyces verruculosus showed remarkable enhancing effects on the hydrolysis of steam-exploded corn stover. Additionally, a synergistic effect was observed for these two cellobiohydrolases during the hydrolysis. Taken together, the constitutive expression system provides a convenient tool for the production of cellulolytic enzymes, which is expected to be useful in the development of highly efficient lignocellulose-degrading enzyme mixtures.

• The Korean Journal of Mycology
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• v.21 no.4
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• pp.301-309
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• 1993

An alkalophilic Cephalosporium sp. RYM-202 capable of producing cellulase components was isolated from soil. This organism grew best at an initial pH 9.0 and produced cellulase maximal at an initial pH 9.5-10.0. Three carboxymethyl cellulases(CMCases), P-I-I, P-I-II and P-II-I, were partially purified by DEAE-Sephadex A-50 ion exchange column followed by Sephadex G-150 gel filtration. The optimum pH values for activity were 7.5 for P-I-I, 8.0-9.5 for P-I-II and 7.5-10.0 for P-II-I. All CMCases were stable between pH 4.5 and 12.0. Temperature optima for activity ranged between 40 and $60^{\circ}C$ and more than 50% of the maximum activity was observed at $20^{\circ}C$ for both of P-I-I and P-II-I. The activity of CMCases was significantly stable in the presence of various laundry components, such as, surfactants, chelating agents and alkaline proteinases.

• Applied Biological Chemistry
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• v.19 no.3
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• pp.139-144
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• 1976

In order to investigate the properties of enzymes from two strains of mold, reported in the previous paper, (1) studies have been made concerning the characteristics of cellulase of Aspergillus niger-SM6 and Trichoderma viride-SM10, and summarized as follows. 1. In the semi-purification the recovery of ${\beta}-glucosidase$ was the highest when 80-90% ethanol was used and 0.8 saturation of $(NH_4)_2SO_4$. 2. The characteristics of the semi-purified enzyme were as follows. Aspergillus niger-SM6 Trichoderma viride-SM10 Optimum pH 3.5 4.0 pH stability 3.0-6.0 3.0-6.0 Optimum temperature $60^{\circ}C$ $60^{\circ}C$ Heat stability below $60^{\circ}C$ below $50^{\circ}C$ Optimum reaction time 30 min. 60 min. Optimum CMC concentration 3% 3% 3. The Km values of CMCase were 0.8% and 1.01 for Aspergillus niger-SM6 and Trichoderma viride-SM10, respectively. 4. In the strain of Aspergillus niger-SM6, there were high activity of xylanase and pectinase.

• Korean Journal of Agricultural Science
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• v.24 no.2
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• pp.275-282
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• 1997

The prcx.iuction of extracellular 1,4-${\beta}$-glucanase by Cellulomonas sp. CS1-1 on microcrystalline cellulose, sigmacell was maximal after 5-day cultivation as 280 units/mL, which was three times higher than the level produced on carboxymethyl cellulose. A carboxymethyl cellulase containing the carbohydrate of 8.2% was purified from the culture filtrate by successive procedures of column chromatographies. Purification factor was calculated as 22-folds with the specific carboxymethyl cellulase activity of 31.9 units/mg. The molecular weight and isoelectric point of the purified enzyme were 54,000 and pI 5.4, respectively. The optimal pH and temperature were 6.0 and $45^{\circ}C$, and the enzyme was stable between pH 6.5 and 7.5 and below $50^{\circ}C$. The estimated Km and Vmax were 10 mg/mL and $6.25{\mu}mol/min$ for carboxymethyl cellulose and 30.3 mg/mL and $2.85{\mu}mol/min$ for sigmacell, respectively. The enzyme was partially inhibited by $Ag^+$, $Zn^{+{+}}$, $Fe^{+{+}}$ and EDTA, while completely inhibited by $Cd^{+{+}}$ and $Hg^{+{+}}$ at 1 mM concentration.

• Journal of Life Science
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• v.12 no.4
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• pp.483-489
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• 2002

We investigated the biochemical properties of insect defensin expressed and secreted from Saccharomyces corevisiae. The defensin showed extremely high resistance to boiling for up to 30 min and to pH values tested from 2.0 to 12.0. The treatment of defensin with various proteases abolished antibacterial activity. However, amylases, cellulase, lipase and catalase had no effect on the activity. The defensin was purified to homogeneity through ammonium sulfate concentration of culture supernatant, SP-Sepharose column chromatography and RP-HPLC. Tricin-SDS-PAGE analysis revealed that the molecular weight of the defensin was about 4.0 kDa. The antibacterial activity of the purified defensin was verified by renaturation of stained gel and gel pouring assay using Micrococcus luteus as a test organism.

• Korean Journal of Agricultural Science
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• v.25 no.1
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• pp.131-137
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• 1998

The cellulase components were partially purified from the culture filtrate of the alkalophilic bacterium Pseudomonas sp. AC-711 and its enzymatic properties were characterized. The specific activity of the purified major enzyme component was 3.5 units/mg protein as carboxymethyl cellulase and the yield was 23% of the total activity of the culture broth. The molecular weight of the component was 46,000 and the Km and Vmax on CMC were determined as $15.4mg\;mL^{-1}$ and $4.17{\mu}moles\;mL^{-1}\;min^{-1}$, respectively. The enzyme was stable at the temperatures below $60^{\circ}C$ and at the pH range of 4.0~11.0, and the optimal temperature and pH were $60^{\circ}C$ and pH 8.0, respectively. The enzyme activity was not significantly affected by the common surfactants (concentration: 0.05%) such as ${\alpha}$-olefin sulfonate, linear alkylbenzene sulfonate, sodium dodecyl sulfonate, hexadecyltrimethylammonium bromide and Tween 80. The enzyme was activated by the metal ions such as $Ca^{2+}$, $Cu^{2+}$, $Co^{2+}$, whereas inhibited by $Hg^{2+}$ and $Zn^{2+}$. The enzyme exhibited relatively high activity toward amorphous CMC as compared with crystalline substrates such as filter paper and avicel.