• Korean Journal of Microbiology
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• v.39 no.3
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• pp.201-205
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• 2003

Laccase, lignin- and manganese peroxidase are implicated in the lignin degradation. The nucleotide sequences of four copper-binding domains in fungal laccases, and heme-binding domains of lignin- and manganese peroxidases are well conserved, and therefore these short fragments can be used for the PCR for the gene amplification. We synthesized several PCR primers according to their sequences, and run PCR to amplifiy the lignin degrading genes of Trametes versicolor isolated in Korea. PCR products were cloned with pGEM-T vector in order to determine their nucleotide sequences. A laccase fragment (1.3 kb) showed 65-97％ homologies, lignin peroxidase fragment (185 bp) showed 80-95％ homologies, and manganese peroxidase fragment (443 bp) showed 61-83％ homologies when compared with other white-rot fungal enzymes.

• Journal of Life Science
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• v.12 no.4
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• pp.392-398
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• 2002

38 strains were isolated in order to utilize lignin degrading ability from soil and compost. A organism having high lignin degrading ability of the isolated strains determined morphologcal and biochemical characteristics. Enrichment technique yielded a lignin degrading bacterium characterized as Pseudomonas sp. LC-2. This strain was able to degrade lignin which are the true representatives of native lignin and transform lignin to a lot of aromatic compounds as HPLC analysis of culture. By polyacrylamide gel analysis, it was determined that peroxidase consisted of three enzymes, with only one, the lignin peroxidase having high activity.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.6
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• pp.422-430
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• 2000

Mechanism of lignin biodegradation caused by basidiomycetes and the history of lignin biodegradation studies were briefly reviewed. The important roles of fungal extracellular ligninolytic enzymes such as lignin and manganese peroxidases (LiP and MnP) were also summarized. These enzymes were unique in their catalytic mechanisms and substrate specificities. Either LiP or MnP system is capable of oxidizing a variety of aromatic substrates via a one-electron oxidation. Extracellular fungal system for aromatic degradation is non-specific, which recently attracts many people working a bioremediation field. On the other hand, an intracellular degradation system for aromatic compounds is rather specific in the fungal cell. Structurally similar compounds were prepared and metabolized, indicating that an intracellular degradation strategy consisted of the cellular systems for substrate recognition and metabolic response. It was assumed that lignin-degrading fungi might be needed to develop multiple metabolic pathways for a variety of aromatic compounds caused by the action of non-specific ligninolytic enzymes on lignin. Our recent results on chemical stress responsible factors analyzed using mRNA differential display techniques were also mentioned.

• Mycobiology
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• v.34 no.4
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• pp.159-165
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• 2006

One of the most economically viable processes for the bioconversion of many lignocellulosic waste is represented by white rot fungi. Phanerochaete chrysosporium is one of the important commercially cultivated fungi which exhibit varying abilities to utilize different lignocellulosic as growth substrate. Examination of the lignocellulolytic enzyme profiles of the two organisms Phanerochaete chrysosporium and Rhizopus stolonifer show this diversity to be reflected in qualitative variation in the major enzymatic determinants (ie cellulase, xylanase, ligninase and etc) required for substrate bioconversion. For example P. chrysosporium which is cultivated on highly lignified substrates such as wood (or) sawdust, produces two extracellular enzymes which have associated with lignin deploymerization. (Mn peroxidase and lignin peroxidase). Conversely Rhizopus stolonifer which prefers high cellulose and low lignin containg substrates produce a family of cellulolytic enzymes including at least cellobiohydrolases and ${\beta}-glucosidases$, but very low level of recognized lignin degrading enzymes.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.2
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• pp.8-14
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• 1999

A screening has been performed to find hyper-ligninolytic fungi, which degtrade beech and pine lignin extensively in order to broaden the understanding of the ligninolytic enzymes elaborated by various white-rot fungi. One hundred and twenty two ligninolytic strains were selected from decayed woods with a selective medium for screening ligninolytic wood-rotting fungi. Two of them, Phanerochaete sordida YK-624 and YK-472, showed much higher ligninolytic activity and selectivity in beech-wood degradation than typical lignin-degrading fungi, phanerochaete chrysosporium and Coriolus versicolor. They also degraded birch dioxane lignin and residual lignin in unbleached kraft pulp(UKP) much more extensively than P. chrysosporium and C. versicolor. During fungal treatment of beech wood-powder, the fungus strain P. sordida YK-624 showed higher activity of extracellular manganese peroxidase (MnP) in the medium than P. chrysosporium. It also showed MnP activity, which would not be lignin peroxidast during treatment of oxygen-bleached kraft pulp(OKP) and under enzyme-inducing conditin.

• Korean Journal of Microbiology
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• v.42 no.1
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• pp.34-39
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• 2006

Wood-rot fungi produce extracellular lignin-degrading enzymes, the best known of which are lignin peroxidase, Mn-peroxidase and laccase. In this experiment, some of them produced all of three enzymes. Many other wood-rot fungi produced one or two of those enzymes with various combinations. In this experiment, we tried to clarify the relationship between the pattern of enzyme production and degradative activity of several dye compounds. From the 36 strains of 23 species of wood-rot fungi, Mn-peroxidase activity was found in 30 strains of the fungi tested, whereas the activity of lignin peroxidase and laccase was detected in 11 strains and 12 strains of species, repectively, in Kirks low nitrogen media. In relation to the activity of lignin degrading enzymes and degradation of dye compounds, the white-rot fungi with three kinds of enzymes tested showed the best dye decolorizers. The fungi with Mn-peroxidase activity only decolorized poly R-478 and remazol brilliant blue R dye in proportion to the enzyme activity, while methylene blue, bromophenol blue and congo red dye were degraded in regardless of enzyme activity. Those dyes were degraded in relation to the growth rate of mycelium. Brown-rot fungi did not degrade all the dye compounds except bromophenol blue, in spite of moderate growth rate.

• Journal of Mushroom
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• v.13 no.1
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• pp.63-67
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• 2015

White rot fungi produce lignin-degrading enzymes such as laccase, manganese peroxidase and lignin peroxidase. These extracellular oxidases efficiently degrade recalcitrant synthetic dyestuffs with diverse chemical structures. Here, we examined the activities of lignin-degrading enzymes in Trametes versicolor using triphenyl methane dyes, crystal violet (CV) and malachite green (MG). Both dyes were decolorized by T. versicolor in solid and liquid culture conditions. T. versicolor decolorized MG more quickly than CV in both conditions. Among three ligninolytic enzymes, laccase was most abundantly found in the decolorization processes of CV and MG. However, higher activity of laccase was needed to degrade CV than MG. The much less activity of MnP was also detected. But the increase of MnP activity was well corresponded to the decolorization efficiency of CV, suggesting the involvement of MnP in CV degrading process. However, its role in the degradation process of MG is supposed to be subsidiary to laccase.

• Korean Journal of Microbiology
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• v.48 no.3
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• pp.225-227
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• 2012

Lignin degrading enzymes from white rot fungi show broad substrate specificities, and therefore they can degrade variety of recalcitrant compounds. We have used three different protocols for the generation of immobilized laccase and manganese peroxidase crude enzymes from the genetically transformed strains of Merulius tremellosus Fr. These immobilized enzymes were used in the decolorization of Remazol Brilliant Blue R (RBBR), and they showed about 75% decolorization rates during the 48 h reactions. Although the decolorization efficiency decreased by 10-15% after a repeated use of the immobilized enzymes, these can be reused in various degrading reactions.

• Journal of Microbiology and Biotechnology
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• v.10 no.6
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• pp.737-752
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• 2000

Wood-rotting basidiomycetous fungi are the most efficient degraders of lignin on earth. The white-rot fungus Phanerochaete chrysosporium has been used as a model microorganism in the study of enzymology and its application. Because of the ability of the white-rot fungus to degrade lignin, which has an irregular structure and large molecular mass, this fungus has also been studied in relation to degrading and mineralizing many environmental pollutants. The fungus includes an array of enzymes, such as lignin peroxidase (LiP), manganese-dependent peroxidase (MnP), cellobiose:quinone oxidoreductase, and $H_2O_2$-producing enzymes and also produces many other components of the ligninolytic system, such as veratryl alcohol (VA) and oxalate. In addition, the fungus has mechanisms for the reduction of degradation intermediates. The ligninolytic systems have been proved to provide reductive reactions as well as oxidative reactions, both of which are essential for the degradation of lignin and organopollutants. Further study on the white-rot fungus may provide many tools to both utilize lignin, the most abundant aromatic polymer, and bioremediate many recalcitrant organopollutants.

• 한국균학회소식:학술대회논문집
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• 2014.10a
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• pp.19-19
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• 2014

Pleurotus ostreatus, P. eryngii, and Flammulina velutipes are major edible mushrooms that account for over 89% of total mushroom production in Korea. Recently, Agrocybe cylindracea, Hypsizygus marmoreus, and Hericium erinaceu are increasingly being cultivated in mushroom farms. In Korea, the production of edible mushrooms was estimated to be 614,224 ton in 2013. Generally, about 5 kg of mushroom substrate is needed to produce 1 kg of mushroom, and consequently about 25 million tons of spent mushroom substrate (SMS) is produced each year in Korea. Because this massive amount of SMC is unsuitable for reuse in mushroom production, it is either used as garden fertilizer or deposited in landfills, which pollutes the environment. It is reasonably assumed that SMS includes different secondary metabolites and extracellular enzymes produced from mycelia on substrate. Three major groups of enzymes such as cellulases, xylanases, and lignin degrading enzymes are involved in breaking down mushroom substrates. Cellulase and xylanase have been used as the industrial enzymes involving the saccharification of biomass to produce biofuel. In addition, lignin degrading enzymes such as laccases have been used to decolorize the industrial synthetic dyes and remove environmental pollutions such as phenolic compounds. Basidiomycetes produce a large number of biologically active compounds that show antibacterial, antifungal, antiviral, cytotoxic or hallucinogenic activities. However, most previous researches have focused on therapeutics and less on the control of plant diseases. SMS can be considered as an easily available source of active compounds to protect plants from fungal and bacterial infections, helping alleviate the waste disposal problem in the mushroom industry and creating an environmentally friendly method to reduce plant pathogens. We describe extraction of lignocellulytic enzymes and antimicrobial substance from SMSs of different edible mushrooms and their potential applications.