• Journal of Microbiology and Biotechnology
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• 제28권7호
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• pp.1217-1224
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• 2018

Seaweeds produce antioxidants to counteract environmental stresses, and these antioxidant genes are regarded as important defense strategies for marine algae. In this study, the expression of Pyropia yezoensis (Bangiales, Rhodophyta) ascorbate peroxidase (PyAPX) and manganese-superoxide dismutase (PyMnSOD) was examined by qRT-PCR in P. yezoensis blades under abiotic stress conditions. Furthermore, the functional relevance of these genes was explored by overexpressing them in Chlamydomonas. A comparison of the different expression levels of PyAPX and PyMnSOD after exposure to each stress revealed that both genes were induced by high salt and UVB exposure, being increased approximately 3-fold after 12 h. The expression of the PyAPX and PyMnSOD genes also increased following exposure to $H_2O_2$. When these two genes were overexpressed in Chlamydomonas, the cells had a higher growth rate than control cells under conditions of hydrogen peroxide-induced oxidative stress, increased salinity, and UV exposure. These data suggest that Chlamydomonas is a suitable model for studying the function of stress genes, and that PyAPX and PyMnSOD genes are involved in the adaptation and defense against stresses that alter metabolism.

• Journal of Microbiology and Biotechnology
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• 제10권6호
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• pp.759-763
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• 2000

Cell-free culture broth of Phanerochaete chrysosporium has been adopted to biologically degrade 2,4,5-trichlorophenol. Two different medium compositions of nitrogen-sufficient and nitrogen-limited were compared for their distribution of isozymes, activity of lignin peroxidase, and production of oxalate. The two different culture broths were tested for their ability to degrade 2,4,5-trichlorophenol, and the biodegradation efficiency was estimated in terms of the disappearance of 2,4,5-trichlorophenol. The degradation efficiency for the nitrogen-limited culture broth was higher than that of the nitrogen-sufficient culture broth, since the nitrogen-limited culture broth induced lignin peroxidases (LiPs) and manganese peroxidases (MnPs), and contained sufficient oxalate for producing necessary radicals. Finally, the possible mechanism of 2,4,5-CP degradation using the nitrogen-limited culture broth was proposed.

• Journal of the Korean Wood Science and Technology
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• 제32권6호
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• pp.14-22
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• 2004

The effect of cadmium ions on ligninolytic and decolourizing activities in cultures of two white-rot fungi, Cerrena unicolor and Trametes versicolor, were examined. Cadmium was added to the shallow stationary cultures growing on a liquid mineral medium. Both examined strains sorbed Cd ions in the first 24 hr of incubation. An appreciable stimulation of the activity of extracellular laccase (LAC) and inhibition of the extracellular manganese-dependent peroxidase (MnP) were simultaneously observed when 25 mgL^-1 and 50 mgL^-1 of cadmium ions were added to the cultures. On the other hand, the addition of cadmium ions also resulted in stimulating the decolorization activity of C. unicolor to decolorize Remazol Brilliant Blue R (RBBR) in the cultures, but decreasing it in the culture of T. versicolor, which is compared to the inhibition of MnP activity in this fungus. Our data indicate that the presence of Cd(II) ions can affect the ligninolytic activity of white-rot fungi. It was found that C. unicolor is a strain resistant to the presence of Cd ions in the liquid culture media, and has a potential to use this strain for bioremediation of sites contaminated with both heavy metals and aromatic pollutants.

• Journal of Microbiology and Biotechnology
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• 제27권1호
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• pp.179-188
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• 2017

White-rot basidiomycetes are the organisms that decompose lignin most efficiently, and Trametes villosa is a promising species for ligninolytic enzyme production. There are several publications on T. villosa applications for lignin degradation regarding the expression and secretion of laccase and manganese peroxidase (MnP) but no reports on the identification and characterization of lignin peroxidase (LiP), a relevant enzyme for the efficient breakdown of lignin. The object of this study was to identify and partially characterize, for the first time, gDNA, mRNA, and the corresponding lignin peroxidase (TvLiP) protein from T. villosa strain CCMB561 from the Brazilian semiarid region. The presence of ligninolytic enzymes produced by this strain grown in inducer media was qualitatively and quantitatively analyzed by spectrophotometry, qPCR, and dye fading using Remazol Brilliant Blue R. The spectrophotometric analysis showed that LiP activity was higher than that of MnP. The greatest LiP expression as measured by qPCR occurred on the $7^{th}$ day, and the ABSA medium (agar, sugarcane bagasse, and ammonium sulfate) was the best that favored LiP expression. The amplification of the TvLiP gene median region covering approximately 50% of the T. versicolor LPGIV gene (87% identity); the presence of Trp199, Leu115, Asp193, Trp199, and Ala203 in the translated amplicon of the T. villosa mRNA; and the close phylogenetic relationship between TvLiP and T. versicolor LiP all indicate that the target enzyme is a lignin peroxidase. Therefore, T. villosa CCMB561 has great potential for use as a LiP, MnP, and Lac producer for industrial applications.

• 펄프종이기술
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• 제31권2호
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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.

• Mycobiology
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• 제46권1호
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• pp.79-83
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• 2018

Azo dyes containing effluents from different industries pose threats to the environment. Though there are physico-chemical methods to treat such effluents, bioremediation is considered to be the best eco-compatible technique. In this communication, we discuss the decolorization potentiality of five azo dyes by Podoscypha elegans (G. Mey.) Pat., a macro-fungus, found growing on the leaf-litter layer of Bethuadahari Wildlife Sanctuary in West Bengal, India. The fungus exhibited high laccase and very low manganese peroxidase activities under different culture conditions. Decolorization of five high-molecular weight azo dyes, viz., Orange G, Congo Red, Direct Blue 15, Rose Bengal and Direct Yellow 27 by the fungus was found to be positive in all cases. Maximum and minimum mean decolorization percentages were recorded in Rose Bengal (70.41%) and Direct Blue 15 (24.8%), respectively. This is the first record of lignolytic study and dye decolorization by P. elegans.

• Mycobiology
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• 제46권4호
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• pp.396-406
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• 2018

A newly isolated white rot fungal strain KU-RNW027 was identified as Trametes polyzona, based on an analysis of its morphological characteristics and phylogenetic data. Aeration and fungal morphology were important factors which drove strain KU-RNW027 to secrete two different ligninolytic enzymes as manganese peroxidase (MnP) and laccase. Highest activities of MnP and laccase were obtained in a continuous shaking culture at 8 and 47 times higher, respectively, than under static conditions. Strain KU-RNW027 existed as pellets and free form mycelial clumps in submerged cultivation with the pellet form producing more enzymes. Fungal biomass increased with increasing amounts of pellet inoculum while pellet diameter decreased. Strain KU-RNW027 formed terminal chlamydospore-like structures in cultures inoculated with 0.05 g/L as optimal pellet inoculum which resulted in highest enzyme production. Enzyme production efficiency of T. polyzona KU-RNW027 depended on fungal pellet morphology as size, porosity, and formation of chlamydospore-like structures.

• Journal of the Korean Wood Science and Technology
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• 제41권1호
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• pp.19-32
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• 2013

본 연구에서는 백색부후균의 리그닌 분해 효소 시스템을 이용하여, 다양한 균주 중에서 목질계 바이오매스 유기용매 전처리 과정에서 발생한 리그닌(유기용매 리그닌)의 생분해에 적합한 우수 균주를 선별하고자 하였다. 우선 분양받은 15개의 백색부후균을 대상으로 shallow stationary cultur (SSC)배지와 malt extract broth (MEB)배지에 유기용매 리그닌의 첨가에 따른 Remazol Brilliant Blue R (RBBR)의 흡광도 변화를 측정하였다. RBBR 탈색능 결과, SSC 배지에서 Ceriporiopsis subvermispora, Ceriporia lacerate, Fomitopsis insularis, Phanerochaete chrysosporium, Polyporus brumalis, Stereum hirsutum 등 6종의 백색부후균에서 급격한 흡광도 변화를 나타냈다. 배양 초기에 급격한 흡광도 변화를 나타낸 6개의 백색부후균을 대상으로 균체 외 단백질 농도 및 리그닌 분해 효소 활성을 측정하였다. 선발된 6개의 균 중에서 S. hirsutum과 P. chrysosporium은 유기용매 리그닌을 첨가한 실험구에서 높은 단백질 농도가 측정되었다. 반면, 리그닌 분해 효소 활성은 F. insularis에서 배양 6일째에 manganese peroxidase (MnP) 활성이 1,545 U/mg, laccase 활성은 1,259 U/mg으로 최고 활성을 나타냈다. 결론적으로, 균체 외 단백질 농도 및 리그닌 분해 효소 활성이 전반적으로 높았던 $STH^*$와 MnP 및 laccase의 활성이 가장 높은 FOI가 유기용매 리그닌 생분해에 유리하게 작용할 것으로 판단된다.

• 한국버섯학회지
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• 제20권2호
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• pp.86-91
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• 2022

큰느타리(Pleurotus eryngii)는 azo계 염료인 CR, heterocyclic계 염료인 MB, triphenyl methane계 염료인 CV와 MG를 고체와 액체 배양 상태에서 모두 분해할 수 있었으며 고체 배양 조건에서는 CR을, 액체 배양 상태에서는 MG을 가장 효과적으로 분해했다. MB는 고체와 액체 배양 조건에서 모두 가정 적게 분해되었다. 4 종류의 염료 모두 균사의 생장을 저해했으나 MG의 영향이 가장 크게 나타났다. 활성을 측정한 두 종류의 리그닌 분해 효소 중 모두 laccase의 활성이 훨씬 높았으며 MnP 역시 활성은 낮았으나 laccsse와 비슷한 경향을 보였다. 따라서 큰느타리는 주로 laccase를 사용하여 방향족 합성염료를 분해하는 것으로 추정된다. CR, MB, CV는 laccase의 활성과 염료 분해 정도가 양의 상관관계를 보인 반면 MG의 경우 높은 효소 활성을 나타낸 후 염료의 분해가 진행되었다. 또한 MG가 모두 분해되었을 때의 laccase 활성(0.07 U/ml)이 다른 염료가 가장 많이 분해되었을 때의 활성(0.10 U/ml)보다 낮았는데 이는 큰느타리의 균사체가 MG를 분해하는 기작이 CR, MB 및 CR 등의 염료를 분해하는 기작과 차이를 보인다는 것을 알 수 있었다. 본 연구에서는 큰느타리의 방향족 합성염료 분해 능력에 대해 밝힘으로써 앞으로 국내산 버섯균주를 이용한 친환경적인 합성염료 처리 기술 개발에 도움을 줄 것으로 기대된다.

• 한국버섯학회지
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• 제13권1호
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• pp.63-67
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• 2015

구름버섯(Trametes versicolor)은 phenolic compound인 CV와 MG를 효과적으로 탈색할 수 있었으며 고체와 액체배양 상태 모두에서 CV보다 MG를 더 효과적으로 탈색시켰다. 구름버섯에 의한 두 색소의 탈색 과정에서 phenolic compounds를 분해하는 것으로 알려진 세 가지 효소 중 laccase의 활성이 가장 높았다. MnP 역시 적은 수치지만 활성을 나타냈으며 LiP의 활성은 나타나지 않았다. 따라서 구름버섯에 의한 합성염료의 분해과정에서 laccase가 주로 사용되고 MnP는 탈색과정에서 보조적인 작용을 하는 것으로 추정된다. 그러나 CV의 경우 MnP가 활발하게 염료분해에 관여하는 것으로 판단된다. 또한 MG가 대부분 탈색되었을 때의 laccase 활성(0.16 U/mg)이 CV가 대부분 탈색되었을 때의 활성(0.23 U/mg)보다 현저하게 낮은 것으로 보아 구름버섯이 CV를 탈색시키는데 더 높은 활성의 laccase가 필요로 하는 것이 밝혀졌다. 본 실험에서 한국산 구름버섯 종의 CV와 MG 탈색능력이 확인되었으며 앞으로 한국산 구름버섯을 이용한 triphenyl methane계에 속하는 합성염료의 분해에 관한 친환경적 처리기술 개발에 도움이 될 것으로 기대된다.