• 한국버섯학회지
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• 제15권4호
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• pp.168-177
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• 2017

To evaluate effects of ligninolytic enzyme type on the mycelial response and ligninolytic enzyme production during interspecific interactions among wood-rotting fungi, 4 fungal strains, Trichophyton rubrum LKY-7, Trichophyton rubrum LSK-27, Pycnoporus cinnabarinus, and Trichoderma viride, were selected. Regarding ligninolytic enzyme production, LKY-7 secreted laccase and manganese peroxidase (MnP), P. cinnabarinus secreted only laccase, and LSK-27 secreted only MnP in glucose-peptone medium, while T. viride did not produce any ligninolytic enzymes. In the co-culture of LKY-7 with P. cinnabarinus, the formation of aerial mycelium was observed and the enhancement of laccase activity owing to interspecific interaction appeared to be very low. In the co-culture of LKY-7 and P. cinnabarinus with LSK-27, a hypha-free clear zone was observed, which resulted in deadlock, and increased laccase or MnP activity was detected at the interaction zone. The interaction responses of LKY-7, P. cinnabarinus, and LSK-27 with T. viride were characterized by the formation of mycelial barrages along the interface. As mycelial barrages were observed at the T. viride territory and no brownish pigment was observed in the mycelial barrages, it is suggested that laccase and MnP are released as part of an offensive response, not as a defensive response. The co-culture of P. cinnabarinus with T. viride lead to the highest enhancement in laccase activity, yielding more than 14-fold increase in laccase activity with respect to the mono-culture of P. cinnabarinus. MnP activities secreted by LKY-7 or LSK-27 was generally low in interspecific interactions.

• Journal of Microbiology and Biotechnology
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• 제26권5호
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• pp.928-937
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• 2016

S-Nitrosoglutathione reductase (GSNOR) metabolizes S-nitrosoglutathione (GSNO) and has been shown to play important roles in regulating cellular signaling and formulating host defense by modulating intracellular nitric oxide levels. The enzyme has been found in bacterial, yeast, mushroom, plant, and mammalian cells. However, to date, there is still no evidence of its occurrence in filamentous fungi. In this study, we cloned and investigated a GSNOR-like enzyme from the filamentous fungus Aspergillus nidulans. The enzyme occurred in native form as a homodimer and exhibited low thermal stability. GSNO was an ideal substrate for the enzyme. The apparent K_m and k_cat values were 0.55 mM and 34,100 min^-1, respectively. Substrate binding sites and catalytic center amino acid residues based on those from known GSNORs were conserved in this enzyme, and the corresponding roles were verified using site-directed mutagenesis. Therefore, we demonstrated the presence of GSNOR in a filamentous fungus for the first time.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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• pp.128-128
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• 1998

Matrix metalloproteinases (MMPs) are a family of zinc-dependent proteases that degrade extracellular matrix and basement membrane. These enzymes are play important roles in tumor cell invasion and metastasis, as well as angiogenesis and other connective tissue diseases. In our screening program for inhibitors of MMP-2 from fungal metabolites, we have isolated novel non-peptidic inhibitors of MMPs, designated gelastatin A and B from the culture broth of Westerdykella multispora F50733. The structures of gelastatin A and B were determined to be 3-(5E-hexa-2E,4E-dienylidene-2-oxo-5,6-dihydro-2H-pyran-3yl)-propanoic acid and 3-(5Z-hexa-2E,4E-dienylidene-2-oxo-5,6-dihydro-2H-pyran-3yl)-propanoic acid, respectively. Gelastatin A and B exist as a mixture of two stereoisomers in a ratio of 2: 1. The 2: 1 mixture of gelastatin A and B inhibited activated MMP-2 and MMP-9 with an IC$\sub$50/ value of 0.63, 5.29 ${\mu}$M, respectively. They inhibited the invasion of B16F10 melanoma cells through basement membrane Matrigel with dose dependent.

• Journal of Microbiology and Biotechnology
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• 제6권6호
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• pp.445-450
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• 1996

Gelatinase A is a member of the matrix metalloproteinases that play an important role in cancer invasion and metastasis. In the course of screening gelatinase A inhibitors from microbial sources, a fungal strain PT-262 showed a strong inhibitory activity. The strain was identified as Chaunopycnis alba on the basis of its morphological characteristics. The inhibitor was isolated from acetone extract of mycelial cake by sequential chromatographies on MCI-gel, Sephadex LH-20, and a reverse-phase HPLC column. The purified inhibitor was identified as pyridoxatin by its physico-chemical properties and spectroscopic analysis. Pyridoxatin is not a peptide analog and has cyclic hydroxamic acid moiety. It inhibited activated gelatinase A with an $IC_{50}$ value of 15.2 ${\mu}M$ using fluorescent synthetic peptide. It also had a strong cytotoxicity against human cancer cell lines in vitro. Furthermore, this compound inhibited DNA synthesis with an $IC_{50}$ value of 2.92 ${\mu}M$ in PC-3 prostate cancer cells by [$^3H$]thymidine incorporation assay.

• 한국미생물·생명공학회지
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• 제22권1호
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• pp.106-113
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• 1994

A novel method for production of concentrated purity maltose using swollen extruded corn starch was investigated. Degree of gelatinization of extruded starch suitable for maltose formation was found to be around 70%. The optimal amiunt of enzyme was 400 unit fungal $\alpha $-amylase per g of starch, and the reaction time was 12 hours. At extruded starch concentration of 300 g/l(w/v), maltose concentration and content were reached up to 220 g/l(w/v) and 77%(w/w), respectively. The maltose forming reaction was also successfully proceeded at high starch concentration of 700 g/l(w/v), however, the conversion yield and content were decreased. By the addition of extruded starch by fed-batch wise, the maltose concentration, purity, and conversion yield could be improved up to 465 g/l(w/v), 70%(w/w), and 0.63, respectively. The investigated maltose production process seems to have many potential advantages over the conventional process utilizing liquefied starch, and the feasibility for industrial application needs to be evaluated.

• 미생물학회지
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• 제53권3호
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• pp.216-218
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• 2017

생물학적방제 효과가 뛰어난 Bacillus thuringiensis C25 균주의 유전체 분석을 수행하였다. 본 균주는 5,308,062 bp, G+C 비율 35.32%의 염색체와 308,946 bp, 32.23% G+C 함량이 포함된 plasmid를 지닌 것으로 확인되었다. 염색체와 plasmid DNA에 예측된 유전자의 총 수는 5,683개의 단백질 코딩유전자와 107개 tRNA 그리고 42개의 rRNA였다.

• 한국균학회지
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• 제24권4호통권79호
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• pp.329-336
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• 1996

From five years' previous work, the fungal isolates of Scopulariopsis were reported to be important flora at the late stage of meju fermentation. Mainly, the white or pale brown powders of spore mass of these fungi were observed on the surfaces of rectangular mejus, and to be an important sign for well-done Korean traditional home - made mejus. Out of the five isolates previously collected and stored, two kinds of Scopulariopsis isolates were identified as S. brevicauli and S. fusca. The microscopic differences between two were found to be branching patterns of annellophore and ornamentations of spore wall (warty and smooth). However, the intermediate form between two ornamentations of spore wall were also observed in our isolates. This observation was consistent with other result made from the protein electrophoresis. The isolates of Scopulariopsis were considered to be similar or superior to those of Aspergillus species, as compared with production of protease and amylase related enzymes. Thus, these isolates were speculated to be important fungi in Korean traditional home - made meju fermentation and also in production of protease and amylase.

• 한국식품과학회지
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• 제13권2호
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• pp.101-106
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• 1981

균류의 세포벽은 복합 다당류의 매우 견고한 막으로 되어있기 때문에 균체의 이용이나 세포막 관련성 효소연구등에 직접적으로 방해가 되어왔기 때문에 이의 제거를 위해 본 실험에서는 Trichoderma viride $TO_4$ 균주에서 얻은 섬유소 가수분해효소와 토양에서 직접 분리한 Streptomyces sp. 115-5균주에서 얻은 chitinase를 혼용하여 각종 균사체에 작용시켜 세포벽의 제거정도에 따른 원형질체 생성을 균체별로 측정하여 그 결과를 얻었다. (1) Ascomycetes 류에서는 반응 3시간후 $3{\times}10^{7}$개의 원형질체가 생성되었다. (2) Zygomycetes류에서는 반응 3시간후 $9{\times}10^7$개의 원형질체가 생성 되었다. (3) 효모류는 이 혼합효소작용에 대하여 별다른 반응을 나타내지 않았다.

• 한국식품과학회지
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• 제22권3호
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• pp.234-240
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• 1990

본 실험에서는 상품화된 단백질 분해효소를 이용한 굴 및 홍합에 대한 최적 가수분해 조건에 대하여 조사하였다. 가수분해도, 유리아미노태 질소, 핵산관련물질, 유리아미노산 및 관능검사로 가수분해물들의 특성을 조사한 결과 굴의 경우 MKC-HT proteolytic, alcalase 0.6L 및 thermoase가, 홍합의 경우 acid-fungal protease와 thermoase가 각 가수분해물 제조시 가장 효과적인 단백질 분해효소임을 확인하였다.

• Mycobiology
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• 제35권1호
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• pp.21-24
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• 2007

To evaluate which dye is effective in a plate assay for detecting extracellular cellulase activity produced by fungi, four chromogenic dyes including remazol brilliant blue, phenol red, congo red, and tryphan blue, were compared using chromagepic media. For the comparison, 19 fungal species belonging to three phyla, ascomycota, basidiomycota, and zygomycota were inoculated onto yeast nitrogen-based media containing different carbon substrates such as cellulose (carboxylmethyl and avicel types) and cellobiose labeled with each of the four dyes. Overall, the formation of clear zone on agar media resulting from the degradation of the substrates by the enzymes secreted from the test fungi was most apparent with media containing congo red. The detection frequency of cellulase activity was also most high on congo red-supplemented media. The results of this study showed that congo red is better dye than other three dyes in, a plate assay for, fungal enzyme detection.