• Title, Summary, Keyword: laccase

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Characterization of Laccase Purified from Korean Trametes hirsuta S1 (한국산 흰구름버섯(Trametes hirsuta S1)으로부터 정제된 Laccase의 특성)

  • Lim, Hyung-Seon;Yoon, Kyung-Ha
    • The Korean Journal of Mycology
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    • v.32 no.2
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    • pp.112-118
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    • 2004
  • Laccase produced by Trametes hirsuta S1 isolated from Korea was partially purified and characterized using ultrafiltration, anion exchange chromatography and affinity chromatography. The laccase was produced as the predominant extracellular enzyme during primary metabolism. Neither lignin peroxidase nor veratryl alcohol oxidase (VAO) were detected in the culture fluid. Addition of 2,5-xylidine enhanced 4-fold laccase production. Purified laccase was a single polypeptide having a molecular mass of approximately 66 kDa, as determined by SDS-polyacrylamide gel electrophoresis, and carbohydrate content of 12%. $K_{m}\;and\;V_{max}$ values for laccase with ABTS [2,2-azinobis (3-ethylbenzthiazoline 6-sulfonic acid)] as a substrate (Lineweaver-Burk plot) was determined to $51.2\;{\mu}M\;and\;56.8\;{\mu}mole$, respectively. The optimal pH for laccase activity was found to be 3.0. The enzyme was very stable for 1 hour at $50^{\circ}C$. Half-life ($t_{1/2}$) of the enzyme was about 20 min at $70^{\circ}C$. Spectroscopic analysis of purified enzyme indicated that the enzyme was typical of copper-containing protein. Substrate specificity and inhibitor studies for laccase also indicated to be a typical fungal laccase. The N-terminal amino acid sequence of the T. hirsuta S1 laccase showed 100% of homology to those of laccase from C. hirsutus.

Oxidation of Acridine by Laccase of Pycnoporus cinnabarinus SCH-3 (주걱송편버섯(Pycnoporus cinnabarinus SCH-3)의 Laccase에 의한 Acridine 산화)

  • Lee, Hyoun-Su;Han, Man-Deuk;Yoon, Kyung-Ha
    • Korean Journal of Microbiology
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    • v.44 no.2
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    • pp.110-115
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    • 2008
  • Acridine was not a substrate for fungal laccase but it was oxidized to acridone in the culture medium of P. cinnabarinus SCH-3. During the cultivation of P. cinnabarinus SCH-3, Laccase was the predominant extracellular phenoloxidase, and 3-hydroxyanthranilic acid (3-HAA) was produced in the early culture. Cinnabarinic acid (CA) was observed to accumulate in the culture medium. When P. cinnabarinus was grown in the culture medium containing acridine, acridine was oxidized to acridone. But when the laccase purified from the culture medium of P. cinnabarinus directly reacted with acridine in sodium tartrate buffer (pH 3.0), The oxidation of acridine did not happen. In contrast, when 3-HAA was added to the buffer that was mixed with laccase and acridine, the acridine was oxidized to acridone. While in vitro studies, the CA was formed from 3-HAA in the presence of purified laccase. The results suggest that the acridine should be oxidized to the acridone through the mediation of 3-HAA by the laccase in the culture medium of P. cinnabarinus SCH-3.

An Immobilization of Extracellular Laccase to Humus-Iron Complex

  • Ginalska, Grazyna;Cho, Nam-Seok;Lobarzewski, Jerzy;Piccolo, Alessandro;Leonowicz, Andrzej
    • Journal of the Korean Wood Science and Technology
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    • v.29 no.3
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    • pp.104-111
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    • 2001
  • There are some evidence that active enzymatic proteins, e.g. fungal laccase, exist in the naturally occured soil humus. This study was performed to investigate the covalent binding of fungal laccase to the humic acid-iron complex, and to measure laccase activity of immobilized ones. Seven methods were adopted to form the covalent binding of fungal laccase with soil humic acids complexed with iron. Using these seven methods it was possible to change the dimension of spacer arm between laccase and support, and also to regulate the mode of covalent binding of this enzyme. The spacer arm was regulated from 2C to 11C. There was not observed any straight relationship between the spacer arm longitude and the laccase activity after immobilization, but the binding mode more effective than the former. Three out of the seven methods gave the high activity of immobilized laccase, and which active products of laccase immobilization was stable up to 10 days after the process. It is indicated that natural soil condition might be prevented the laccase activation by the toxic influence of some phenolic humic compounds. It was shown, for the first time, the possibilities to obtain the high activity of fungal laccase by binding to humic acids, and especially in complex with iron.

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Cloning and expression of new laccase gene (soncotA) from Bacillus sonorensis KCTC13918 in E. coli (Bacillus sonorensis KCTC13918로부터 새로운 laccase유전자 (soncotA)의 클로닝과 대장균에서의 발현)

  • Choi, Shin-Geon;Yoon, Hyeonjong
    • Journal of Industrial Technology
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    • v.37 no.1
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    • pp.16-20
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    • 2017
  • A new putative laccase gene (soncotA) which show 78% homology with that from Bacillus licheniformis (liccotA) was isolated from draft genome sequence of Bacillus sonorensis KCTC 13918. A 1,545 bp of PCR product corresponding 514 amino acids was cloned into NdeI-NotI site of pET21c and expressed as soluble form in E. coli. About 59 kDa size of recombinant laccase was purified into homogenity by Ni-NTA column and laccase activity was confirmed by zymography. The enzymatic properties of recombinant laccase were characterized. The specific activity of B. sonorensis laccase was 0.033 fold lower than that of Bacillus licheniformis laccase. The finding of new laccase gene broadened the enzymatic diversity of Bacillus species laccases.

Continuous Degradation of azo dye by Immobilized laccase (고정화 laccase에 의한 azo 염료의 연속 분해)

  • Kwon, Sin;Ryu, Won-Ryul;Cho, Moo-Hwan
    • KSBB Journal
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    • v.17 no.2
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    • pp.189-194
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    • 2002
  • Laccase produced from Trametes sp. was immobilized on CNBr-activated Sepharose-4B (CAS4B) and tested for degradation of azo dyes. Laccase was efficiently immobilized on CAS4B. Immobilization of laccase on CAS4B increased pH, thermal and proteolytic stabilities. Optimum pH and temperature of immobilized laccase were pH 3 and 40$\^{C}$, respectively as same as those of free laccase. The K$\_$m/($\mu$mol/ml) values of free and immobilized laccase for Reactive Blue 19 as the substrate were 0.34 and 2.07, respectively V$\_$max/($\mu$mol/mL$.$min) values of them were 0.12 and 0.1, respectively. In repeated batch reactions, conditions retained high stability and degradation of dye for immobilized laccase were pH 5 and 30$\^{C}$. HBT didn\\`t decrease highly activity of immobilized laccase. Immobilized laccase was very stable for degrading dyes continuously in a packed-bed reactor containing laccase immobilized on CAS4B. For continuous degradation of 100 $\mu$M Reactive Blue 19 and 50 $\mu$M Acid Red 57 in the presence of 0.1 mM HBT under optimum conditions, immobilized laccase retained 70% of degradation ability even after 30 hours.

Purification and Characterization of Laccase from Wood-Degrading Fungus Trichophyton rubrum LKY-7

  • Hyunchae Jung;Park, Chongyawl;Feng Xu;Kaichang Li
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • pp.18-25
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    • 2001
  • A new wood-degrading fungus Trichophyton rubrum LKY-7 secretes a high level of laccase in a glucose-peptone liquid medium. The production of laccase by the fungus was barely induced by 2,5-xylidine. The laccase has been purified to homogeneity through three chromatography steps in an overall yield of 40%. The molecular mass of the purified laccase was about 65 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The purified laccase had the distinct blue color and had basic spectroscopic features of a typical blue laccase: two absorption maxima at 278 and 610 nm and a shoulder at 338 nm. The N-terminus of the laccase has been sequenced, revealing high homology to laccases from wood-degrading white-rot fungi such as Ceriporiopsis subvermispora. The enzyme had a "low" redox potential (0.5 V vs normal hydrogen electrode), yet it was one of the most active laccases in oxidizing a series of representative substrates/mediators. Compared with other fungal laccases, the laccase has a very low Km value with ABTS [2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid] as a substrate and a very high Km value with violuric acid as a substrate. The laccase has the isoelectric point of 4.0. The laccase had very acidic optimal pH values (pH 3-4) while it was more stable at neutral pH than at acidic pH. The laccase oxidized hydroquinone faster than catechol and pyrogallol. The oxidation of tyrosine by the laccase was not detectable under the reaction conditions. The laccase was strongly inhibited by sodium azide and sodium fluoride. fluoride.

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Optimizing Culture Conditions to Maximize the Production of Laccase from Pholiota highlandensis (Pholiota highlandensis 유래 laccase 생산을 위한 배양조건의 최적화)

  • Choi, Hye-Ju;Moon, Soo-Jung;Jeon, Sung-Jong
    • Journal of Life Science
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    • v.25 no.6
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    • pp.673-679
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    • 2015
  • The culture conditions needed to maximize the production of laccase from Pholiota highlandensis mycelia were investigated. Among the tested media for laccase production, Coriolus versicolor medium (CVM; 2% dextrose, 0.4% peptone, 0.6% yeast extract, 0.046% KH2PO4, 0.1% K2HPO4, 0.05% MgSO4·7H2O) showed the highest activity for the enzyme. Then, to optimize culture conditions for laccase activity, the influences of various carbon, nitrogen, phosphorus, and inorganic salt sources in CVM were investigated. The optimum culture medium was 2% fructose, 0.4% peptone with 0.6% yeast extract, 0.05% NaH2PO4, and 0.05% MgSO4·7H2O as carbon, nitrogen, phosphorus, and inorganic salt sources, respectively. Several aromatic compounds in the medium enhanced laccase activity to varying degrees. Guaiacol induced maximum laccase production, yielding 114.1 U/ml laccase activity after cultivation for 11 days at 25℃. The optimum pH and temperature for laccase production were 8.0 and 35℃, respectively. Native polyacrylamide-gel electrophoresis (PAGE) followed by laccase-activity staining with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) as the substrate was performed to identify the presence of laccase under the optimum conditions studied. Zymogram analysis of the supernatant culture showed an enzymatic band with a molecular mass of about 90 kDa.

Characterization of Laccase Purified from Korean Pycnoporus cinnabarinus SCH-3 (한국산 주걱송편버섯(Pycnoporus cinnabarinus) SCH-3로부터 정제 된 Laccase의 특성)

  • Park, Eun-Hye;Yoon, Kyung-Ha
    • The Korean Journal of Mycology
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    • v.31 no.2
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    • pp.59-66
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    • 2003
  • Laccase produced by Pycnoporus cinnabarinus SCH-3 isolated from Korea was partially purified using ultrafiltration, anion exchange chromatography and affinity chromatography, The laccase was produced as the predominant extracellular phenoloxidase during primary metabolism. Neither lignin peroxidase nor manganese-dependent peroxidase were detected in the culture fluid. In order to examine the effect of inducers in laccase production, 2,5-xylidine was added in the culture of Pycnoporus cinnabarinus SCH-3. Addition of 2,5-xylidine enhanced 25-fold laccase production. Purified laccase was a single polypeptide having a molecular mass of approximately 66 kDa, as determined by SDS-polyacrylamide gel electrophoresis, and carbohydrate content of 9%. $K_{m}\;and\;V_{max}$ values for laccase with ABTS [2,2-azinobis (3-ethylbenzthiazoline 6-sulfonic acid)] as a substrate (Lineweaver-Burk plot) was determined to be $44.4{\mu}M\;and\;56.0{\mu}mole$, respectively. The optimal pH for laccase activity was found to be 3.0. The enzyme was very stable for 1 hour at $60{\circ}C$. Half-life ($t_{1/2}$) of the enzyme was about 10 min at $80{\circ}C$. Spectroscopic analysis of purified enzyme indicated that the enzyme was typical of copper-containing protein. Substrate specificity and inhibitor studies for laccase also indicated to be a typical fungal laccase. The N-terminal amino acid sequence of the P. cinnabarinus SCH-3 laccase showed 94% of homology to the N-terminal sequences of laccases from P. cinnabarinus PB and P. coccineus.

Physiological Regulation of an Alkaline-Resistant Laccase Produced by Perenniporia tephropora and Efficiency in Biotreatment of Pulp Mill Effluent

  • Teerapatsakul, Churapa;Chitradon, Lerluck
    • Mycobiology
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    • v.44 no.4
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    • pp.260-268
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    • 2016
  • Regulation of alkaline-resistant laccase from Perenniporia tephropora KU-Alk4 was proved to be controlled by several factors. One important factor was the initial pH, which drove the fungus to produce different kinds of ligninolytic enzymes. P. tephropora KU-Alk4 could grow at pH 4.5, 7.0, and 8.0. The fungus produced laccase and MnP at pH 7.0, but only laccase at pH 8.0. The specific activity of laccase in the pH 8.0 culture was higher than that in the pH 7.0 culture. At pH 8.0, glucose was the best carbon source for laccase production but growth was better with lactose. Low concentrations of glucose at 0.1% to 1.0% enhanced laccase production, while concentrations over 1% gave contradictory results. Veratryl alcohol induced the production of laccase. A trace concentration of copper ions was required for laccase production. Biomass increased with an increasing rate of aeration of shaking flasks from 100 to 140 rpm; however, shaking at over 120 rpm decreased laccase quantity. Highest amount of laccase produced by KU-Alk4, 360 U/mL, was at pH 8.0 with 1% glucose and 0.2 mM copper sulfate, unshaken for the first 3 days, followed by addition of 0.85 mM veratryl alcohol and shaking at 120 rpm. The crude enzyme was significantly stable in alkaline pH 8.0~10.0 for 24 hr. After treating the pulp mill effluent with the KU-Alk4 system for 3 days, pH decreased from 9.6 to 6.8, with reduction of color and chemical oxygen demand at 83.2% and 81%, respectively. Laccase was detectable during the biotreatment process.

Laccase Production Using Pleurotus ostreatus 1804 Immobilized on PUF Cubes in Batch and Packed Bed Reactors: Influence of Culture Conditions

  • Prasad K. Krishna;Mohan S. Venkata;Bhaskar Y. Vijaya;Ramanaiah S. V.;Babu V. Lalit;Pati B. R.;Sarma P. N.
    • Journal of Microbiology
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    • v.43 no.3
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    • pp.301-307
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    • 2005
  • The feasibility of laccase production by immobilization of Pleurotus ostreatus 1804 on polyurethane foam (PUF) cubes with respect to media composition was studied in both batch and reactor systems. Enhanced laccase yield was evidenced due to immobilization. A relatively high maximum laccase activity of 312.6 U was observed with immobilized mycelia in shake flasks compared to the maximum laccase activity of free mycelia (272.2 U). It is evident from this study that the culture conditions studied, i.e. biomass level, pH, substrate concentration, yeast extract concentration, $Cu^{2+}$ concentration, and alcohol nature, showed significant influence on the laccase yield. Gel electrophoretic analysis showed the molecular weight of the laccase produced by immobilized P. ostreatus to be 66 kDa. The laccase yield was significantly higher and more rapid in the packed bed reactor than in the shake flask experiments. A maximum laccase yield of 392.9 U was observed within 144 h of the fermentation period with complete glucose depletion.