• KSBB Journal
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• v.11 no.4
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• pp.470-475
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• 1996

A white rot fungus as a microbial source producing bioflocculant was isolated from rotted leaves and identified as Pestalotiopsis sp. M01. The flocculating activity and productivity of Pestan produced by Pestalotiopsis sp. KCTC 8637P was determined by using Czapek-Dox medium as the inorganic salt source. The flocculating activity was highest at 3% sucrose and 0.3% $KN0_3$, pH 7, and $25^{\circ}C$, respectively. Whilst, the strain growth was highest at 3% sucrose, 0.3% TEX><$KN0_3$, pH 5, and $25^{\circ}C$, respectively.

• Journal of the Korean Wood Science and Technology
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• v.14 no.3
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• pp.36-42
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• 1986

The production media and the enzymatic charateristics of laccase from Flammulina velutipes were investigated. The activity of laccase during incubation reached to the maximum at the 40 days of incubation in the case of Barley straw medium. The maximum laccase activity in Barley straw medium was 5 and 16 times higher than those in Onion basic and Sawdust media, respectively. The laccase from Flammulina velutipes has the optimum pH of 6.6 and showed to be stable at relatively broad pH range. 4.5-9.5. Temperature stability showed that above 96% activity could be preserved after holding at 40$^{\circ}C$ for 40 minutes. At the above 70$^{\circ}C$, the laccase activity decreased very rapidly. The Km value of the laccase was estimated to be 28.0 mM which is much higher than that of the laccase from Pleurotus ostreatus. Organic solvents for precipitiation of the enzyme did not inactivation the laccase. Sodium azide which was added for preventing microbial deterioration affected significantly the inactivation of laccase, but this activity was recovered completely by precipitating the enzyme with acetone.

• Mycobiology
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• v.42 no.4
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• pp.322-330
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• 2014

The aim of this study was to identify and characterize new Flammulina velutipes laccases from its whole-genome sequence. Of the 15 putative laccase genes detected in the F. velutipes genome, four new laccase genes (fvLac-1, fvLac-2, fvLac3, and fvLac-4) were found to contain four complete copper-binding regions (ten histidine residues and one cysteine residue) and four cysteine residues involved in forming disulfide bridges, fvLac-1, fvLac-2, fvLac3, and fvLac-4, encoding proteins consisting of 516, 518, 515, and 533 amino acid residues, respectively. Potential N-glycosylation sites (Asn-Xaa-Ser/Thr) were identified in the cDNA sequence of fvLac-1 (Asn-454), fvLac-2 (Asn-437 and Asn-455), fvLac-3 (Asn-111 and Asn-237), and fvLac4 (Asn-402 and Asn-457). In addition, the first 19~20 amino acid residues of these proteins were predicted to comprise signal peptides. Laccase activity assays and reverse transcription polymerase chain reaction analyses clearly reveal that $CuSO_4$ affects the induction and the transcription level of these laccase genes.

• Journal of Microbiology and Biotechnology
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• v.22 no.2
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• pp.239-243
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• 2012

Degradation of butylbenzyl phthalate (BBP) by the white rot fungus Pleurotus ostreatus and the activities of some degrading enzymes were examined in two different media containing 100 mg/l of the compound. P. ostreatus pre-grown for 7 days in complex YMG medium was able to completely degrade BBP within an additional 24 h but degraded only 35 mg/l of BBP in 5 days of incubation in minimal medium. Fungal cell mass in the culture in YMG medium was higher in the presence than in the absence of BBP. The esterase activity of the fungal culture in YMG medium was higher than that in minimal medium and increased with the addition of BBP. On the contrary, laccase activity was higher in minimal medium and it did not increase upon the addition of BBP. General peroxidase activity increased for a few days after the addition of BBP to both media. The degradation of BBP and its metabolites by P. ostreatus thus may be attributed mostly to esterase rather than lignin-degrading laccase. In addition, the activities of the enzymes involved in BBP degradation and their changes varied significantly in the different media and culture conditions.

• Journal of Microbiology
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• v.37 no.4
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• pp.229-233
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• 1999

The mitochondrial plasmid pMLP1 from a white-rot fungus, Pleurotus ostreatus, is a double-stranded DNA containing 381 bp terminal inverted repeat (TIR) whose 5'-ends are covalently bound by terminal proteins. The plasmid contains two major open reading frames (ORFs), encoding putative DNA and RNA polymerases, and a minor ORF encoding a small, highly basic protein. To identify the DNA binding activity that recognizes the TIR region of pMLP1, gel retardation assays were performed with mitochondrial extracts. A specific protein binding to a region between 123 and 248 nt within TIR was observed. We examined whether the gene product of mORF1 bindes to this region specifically. E. coli cell extract which contains an overproduced mORF1 protein formed a complex specific to the region between 123 and 248 nt. Inclusion of mORF1 protein in the specific complex formed between P. ostreatus mitochondrial extract and TIR was confirmed by a supershift assay using polyclonal antibodies against the mORF1 protein. Our result suggest that the product of mORF1 may function as a terminal region recognition factor (TRF), recognizing an internal region in TIR.

• Research in Plant Disease
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• v.9 no.2
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• pp.85-88
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• 2003

A sclerotinia rot of Water cress (Oenanthe javanica) occurred in the commerical farmers field at Garye-myon, Uiryeong-gun, Gyeongnam Province, Korea, 2002. The typical symptoms appeared on leaves and stems. At first, the infected leaves or stems turned dark green later become watery soft rotted; white fluffy mycelia grew from the lesion, later formed black sclerotia. Sclerotia on the infected plants and PDA medium were globose to cylindrical or irregular in shape and 1.0~10.7 ${\times}$1.0~7.6 mm in size. Cup-shaped aphothecia with numerous asci were formed from sclerotinia and the size were 0.4~1.6 cm in diameter. Asci with 8 spores were cylindrical and 74~236 ${\times}$ 4.2~24.8 m in size. Ascospores of one cell were hyaline, ellipsoid to ovoid in shape, and 8.3~12.4 ${\times}$ 3.6~7.2 m in size. The optimum temperature for mycelial growth was $25^{\circ}C$ , and sclerotinia forma-tion was between 15~$20^{\circ}C$. On the basis of mycological characteristics and pathogenecity test to host plants, the fungus was identified as Sclerotinia sclerotiorum. This is the first report of Sclerotinia sclerotiorum caused sclerotinia rot on Oenanthe javanica caused by in Korea.

• Research in Plant Disease
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• v.12 no.3
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• pp.290-293
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• 2006

A fruit rot of sweet persimmon(Diospyros kaki cv. 'Fuyu') that infected with blue mold was found during the storage and transport in Jinju Gyeongnam Province, Korea. Fruit surfaces that infected with the fungus were formed water soaked lesion at first then gradually colonized with the fungus and formed mycelial mats. From the point of infection, fruits become sunken and mostly ruptured. The pathogenic fungus was isolated from infected fruits and cultured on potato dextrose agar. The colonies of the pathogenic fungi were white at frist then became greyish green on malt extract agar. Conidia were ellipsoidal and $2.6{\sim}3.8{\times}2.4{\sim}3.8{\mu}m$ in size. Phialides were ampulliform, verticilate of 3-7, $8.0{\sim}9.2{\times}2.0{\sim}3.0{\mu}m$ in size. Metulae were verticils of 2-4, smooth, $9.0{\sim}12.6{\times}3.0{\sim}4.6{\mu}m$ in size. Ramuli were groups 1-3, smooth, $11.0{\sim}17.6{\times}2.3{\sim}3.0{\mu}m$ in size. Rami were groups 1-2, $7.5{\sim}32.6{\times}2.6{\sim}4.2{\mu}m$ in size. Stipes were septate, smooth, thin walled, $56{\sim}302{\times}2.8{\sim}4.0{\mu}m$ in size. Penicilli were mostly quaterverticillate. Based on the cultural and mycological characteristics as well as pathogenicity test on host plants, the fungus was identified as Penicillium expansum. This is the first report on the blue mold of sweet persimmon(Diospyros kaki) caused by P. expansum in Korea.

• Research in Plant Disease
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• v.17 no.3
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• pp.402-404
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• 2011

The Sclerotium blight was found on Phalaenopsis spp. at Dong-du-cheon city, and Hwa-seong city, Gyenggido, Korea in September 2009. The symptom included yellowing on lower leaves and wilt of a whole plant. Severely infected plants were blighted and died eventually. White mycelial mats appeared on the surface of basal stem and bulbs and the sclerotia were formed on stems, roots, and sphagnum moss. The sclerotia were spherical, 1-3 mm and white to brown. The optimum temperature for the growth and sclerotia formation was $25-30^{\circ}C$ on PDA. On the pathogenicity test, the first symptom appeared 5 days after inoculation and developed to severe stem rot and blight. On the basis of mycological characteristics and pathogenicity, the causal fungus was identified as Sclerotium rolfsii. This is the first report on the sclerotium blight on Phalaenopsis spp. caused by Sclerotium rolfsii in Korea.

• Research in Plant Disease
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• v.16 no.3
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• pp.320-322
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• 2010

The Sclerotium blight was found on Neofinetia falcata at Yong-in city, Gyenggi-do, Korea. The symptom occurred low leaves yellowish and wilt of a whole plant. Severely infected plants were blighted and dies eventually. White mycelial mats appeared on the surface of basal stem and bulbs and the sclerotia were formed on stems, roots, and sphagnum moss. The sclerotia were spherical in shape, 1~3 mm in size and white to brown in color. The optimum temperature for the growth and sclerotia formation was $25{\sim}30^{\circ}C$ on PDA. On the pathogenicity test, the first symptom was appeared 5 days after inoculation and development to severe stem rot and blight. The causal fungus was identified as Sclerotium rolfsii and we suggested to call that the new Sclerotium blight on Neofinetia falcata caused by Sclerotium rolfsii in Korea.

• Journal of Mushroom
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• v.17 no.4
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• pp.247-254
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• 2019

Trametes hirsuta, a white rot fungus, exhibits the ability to degrade synthetic aromatic dyes such as congo red (CR), methylene blue (MB), crystal violet (CV), and remazol brilliant blue R (RBBR). The mycelia of T. hirsuta degraded RBBR and CR more efficiently than CV and MB in the PDB liquid medium (supplemented with 0.01% 4 aromatic dyes). In these mycelia the activities of three ligninolytic enzymes-laccase, manganese peroxidase (MnP), and lignin peroxidase (LiP)-were observed. Among these, laccase was identified to be the major enzyme responsible for the degradation of the four aromatic dyes. The degradation of bisphenol A was also investigated by culturing the mycelia of T. hirsuta in YMG medium supplemented with 100 ppm bisphenol A. The mycelia of T. hirsuta were found to degrade bisphenol A by 71.3, 95.3, and 100 % within incubation periods of 12, 24, and 36 hr, respectively. These mycelia also showed ligninolytic enzyme-like activities including those similar to laccase, MnP, and LiP. Therefore, these results indicate that T. hirsuta could emerge as a potential tool for the remediation of environmental contamination by aromatic dyes and bisphenol A.