• 한국균학회소식:학술대회논문집
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• 2014.10a
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• pp.9-9
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• 2014

Null mutants generated by targeted gene replacement are frequently used to reveal function of the genes in fungi. However, targeted gene deletions may be difficult to obtain or it may not be applicable, such as in the case of redundant or lethal genes. Constitutive expression system could be an alternative to avoid these difficulties and to provide new platform in fungal functional genomics research. Here we developed a novel platform for functional analysis genes in Magnaporthe oryzae by constitutive expression under a strong promoter. Employing a binary vector (pGOF1), carrying $EF1{\beta}$ promoter, we generated a total of 4,432 transformants by Agrobacterium tumefaciens-mediated transformation. We have analyzed a subset of 54 transformants that have the vector inserted in the promoter region of individual genes, at distances ranging from 44 to 1,479 bp. These transformants showed increased transcript levels of the genes that are found immediately adjacent to the vector, compared to those of wild type. Ten transformants showed higher levels of expression relative to the wild type not only in mycelial stage but also during infection-related development. Two transformants that T-DNA was inserted in the promotor regions of putative lethal genes, MoRPT4 and MoDBP5, showed decreased conidiation and pathogenicity, respectively. We also characterized two transformants that T-DNA was inserted in functionally redundant genes encoding alpha-glucosidase and alpha-mannosidase. These transformants also showed decreased mycelial growth and pathogenicity, implying successful application of this platform in functional analysis of the genes. Our data also demonstrated that comparative phenotypic analysis under over-expression and suppression of gene expression could prove a highly efficient system for functional analysis of the genes. Our over-expressed transformants library would be a valuable resource for functional characterization of the redundant or lethal genes in M. oryzae and this system may be applicable in other fungi.

• Particle and aerosol research
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• v.8 no.4
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• pp.143-150
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• 2012

Fungal particles have been known to aggravate indoor air quality. To develop fungal particle cleaning devices requires a well-controlled generator of fungal aerosol particles. In this study, a novel fungal aerosol generator was designed and tested for anti-fungal experiment. Cladosporium cladosporioides was selected as test fungal particle. After aerosolization, the number concentration and the size of particles were measured by aerodynamic particle sizer. The number concentration depended on the vibration strength and vibration period of the designed fungal aerosol generator. For the vibration strength of 10volt and the period of 10 sec (5 sec on and 5 sec off), the stable particle generation with concentration of 10#/cm3 was maintained during 35 minutes.

• The Plant Pathology Journal
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• v.25 no.1
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• pp.108-111
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• 2009

DNA-based studies, including cloning and genotyping, have become routine in fungal research laboratories. However, preparation of high-quality DNA from fungal tissue requires much time and labor and is often a limiting step for high-throughput experiments. We have developed a quick and safe (QS) DNA extraction method for fungi. Time efficiency and safety in the QS method were achieved by using plate-grown mycelia as the starting material, by eliminating phenol-chloroform extraction procedures, and by deploying a simple electric grinder. This QS method is applicable not only to a broad range of microbial eukaryotes, including true fungi and oomycetes, but also to lichens and plants.

• Journal of Environmental Health Sciences
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• v.36 no.1
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• pp.27-32
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• 2010

The indoor environmental condition was assessed in houses with allergy (asthma and atopy) patients by use of a fungal detector. The fungal index was calculated from the growth rate of the sensor fungi in a fungal detector encapsulating the spores, Alternaria alternata S-78, Eurotium herbariorum J-183 and Aspergillus penicillioides K-712. Fungal indices were higher in asthma patient's houses than in control houses and Eurotium herbariorum showed the highest growth response among the sensor fungi. Dust mites allergen, Der f1, was also significantly high in allergy patient's houses where fungal indices above 10 were detected. A correlation was observed between the fungal indices and dust mite allergen proliferations in examined houses. Therefore, the fungal index can be a useful tool as an indirect indication for detecting chronic dampness that brings both contaminations by fungi and dust mite.

• Genomics & Informatics
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• v.4 no.4
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• pp.147-160
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• 2006

GATA transcription factors are widespread eukaryotic regulators whose DNA-binding domain is a class IV zinc finger motif in the form $CX_{2}CX_{17-20}CX_{2}C$followed by a basic region. In fungi, they act as transcriptional activators or repressors in several different processes, ranging from nitrogen source utilization to mating-type switching. Using an in-house bioinformatics portal system, we surveyed 50 fungal and 9 out-group genomes and identified 396 putative fungal GATA transcription factors. The proportion of GATA transcription factors within a genome varied among taxonomic lineages. Subsequent analyses of phylogenetic relationships among the fungal GATA transcription factors, as well as a study of their domain architecture and gene structure, demonstrated high degrees of conservation in type IVa and type IVb zinc finger motifs and the existence of distinctive clusters at least at the level of subphylum. The SFH1 subgroup with a 20-residue loop was newly identified, in addition to six well-defined subgroups in the subphylum Pezizomycotina. Furthermore, a novel GATA motif with a 2f-residue loop ($CX_{2}CX_{21}CX_{2}C$, designated 'zinc finger type IVc') was discovered within the phylum Basidiomycota. Our results suggest that fungal GATA factors might have undergone multiple distinct modes of evolution resulting in diversified cellular modulation in fungi.

• Mycobiology
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• v.48 no.5
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• pp.351-363
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• 2020

Here, we investigated fungal microbiota in the understory root layer of representative well-conserved geographically segregated natural wetlands in the Korean Peninsula. We obtained 574,143 quality fungal sequences in total from soil samples in three wetlands, which were classified into 563 operational taxonomic units (OTU), 5 phyla, 84 genera. Soil texture, total nitrogen, organic carbon, pH, and electrical conductivity of soil were variable between geographical sites. We found significant differences in fungal phyla distribution and ratio, as well as genera variation and richness between the wetlands. Diversity was greater in the Jangdo islands wetland than in the other sites (Chao richness/Shannon/Simpson's for wetland of the Jangdo islands: 283/6.45/0.97 > wetland of the Mt. Gariwang primeval forest: 169/1.17/0.22 > wetland of the Hanbando geology: 145/4.85/0.91), and this variance corresponded to the confirmed number of fungal genera or OTUs (wetlands of Jangdo islands: 42/283> of Mt. Gariwang primeval forest: 32/169> of the Hanbando geology: 25/145). To assess the uniqueness of the understory root layer fungus taxa, we analyzed fungal genera distribution. We found that the percentage of fungal genera common to two or three wetland sites was relatively low at 32.3%, while fungal genera unique to each wetland site was 67.7% of the total number of identified fungal species. The Jangdo island wetland had higher fungal diversity than did the other sites and showed the highest level of uniqueness among fungal genera (Is. Jangdo wetland: 34.5% > wetland of Mt. Gariwang primeval forest: 28.6% > wetland of the Hanbando geology: 16.7%).

• Journal of Life Science
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• v.16 no.3 s.76
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• pp.387-395
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• 2006

To isolate and purify anti-fungal active substances from immunized housefly (Musca domestica), low dose of Candida albicans was injected into the larvae of the housefly to induce the appearance of potent anti-fungal active substances in the hemolymph. This purification work was performed by the routine isolation and purification processes of protein, namely, solid phase extraction (SPE), SDS-PACE electrophoresis, HPLC purification. Three 4-16 kDa peptides which exhibited antifungal activity against Candida albican and other fungi were isolated from induced hemolymph. Consequently, further anti-fungal activity study showed that these three peptides were different either in molecular weight or in anti-fungal activity. All isolated substances were proved to be active and resistant to high-temperature. It was deduced that these peptides isolated from induced housefly were novel members of the insect defensin family and they were inducible.

• Journal of Ginseng Research
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• v.36 no.3
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• pp.327-333
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• 2012

Fungal endophytes were isolated from 1-, 2-, 3-, and 4-year-old ginseng roots (Panax ginseng Meyer) cultivated in Korea. The isolated fungal endophytes were identified based on sequence analysis of the internal transcribed spacer and morphological characterization by microscopic observations. A total of 81 fungal endophytes were isolated from 24 ginseng roots. Fungal endophytes were classified into 9 different fungal species and 2 unknown species. Ginseng roots that were 1-, 2-, 3-, and 4-years old were colonized by 2, 6, 8, and 5 species of fungal endophytes, respectively. While Phoma radicina was the most frequent fungal endophyte in 2-, 3-, and 4-year-old ginseng roots, Fusarium solani was the dominant endophyte in 1-year-old ginseng roots. The colonization frequencies (CF) varied with the host age. The CF were 12%, 40%, 31%, and 40% for 1-, 2-, 3-, and 4-year-old ginseng roots, respectively. We found a variety of fungal endophytes that were distributed depending on the age of ginseng plants.

• Journal of Ginseng Research
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• v.36 no.1
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• pp.107-113
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• 2012

In order to investigate the diversity of endophytes, fungal endophytes in Panax ginseng Meyer cultivated in Korea were isolated and identified using internal transcribed spacer (ITS) sequences of ribosomal DNA. Three cultivars of 3-year-old ginseng roots (Chunpoong, Yunpoong, and Gumpoong) were used to isolate fungal endophytes. Surface sterilized ginseng roots were placed on potato dextrose agar plates supplemented with ampicilin and streptomycin to inhibit bacterial growth. Overall, 38 fungal endophytes were isolated from 12 ginseng roots. According to the sequence analysis of the ITS1-5.8S-ITS2, 38 fungal isolates were classified into 4 different fungal species, which were Phoma radicina, Fusarium oxysporum, Setophoma terrestris and Ascomycota sp. 2-RNK. The most dominant fungal endophyte was P. radicina in 3 cultivars. The percentage of dominant endophytes of P. radicina was 65.8%. The percentage of colonization frequency of P. radicina was 80%, 52.9%, and 75% in Chunpoong, Yunpoong, and Gumpoong, respectively. The second most dominant fungal endophyte was F. oxysporum. The diversity of the fungal endophytes was low and no ginseng cultivar specificity among endophytes was detected in this study. The identified endophytes can be potential fungi for the production of bioactive compounds and control against ginseng pathogens.

• Mycobiology
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• v.50 no.5
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• pp.345-356
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• 2022

The fungal distribution, diversity, and load were analyzed in the geographically segregated island groundwater systems in Korea. A total of 79 fungal isolates were secured from seven islands and identified based on the internal transcribed spacer (ITS) sequences. They belonged to three phyla (Ascomycota, Basidiomycota, and Chlorophyta), five classes, sixteen orders, twenty-two families, and thirty-one genera. The dominant phylum was Ascomycota (91.1%), with most fungi belonging to the Cladosporium (21.5%), Aspergillus (15.2%), and Stachybotrys (8.9%) genera. Cladosporium showed higher dominance and diversity, being widely distributed throughout the geographically segregated groundwater systems. Based on the diversity indices, the genera richness (4.821) and diversity (2.550) were the highest in the groundwater system of the largest scale. As turbidity (0.064-0.462) increased, the overall fungal count increased and the residual chlorine (0.089-0.308) had low relevance compared with the total count and fungal diversity. Cladosporium showed normal mycelial growth in de-chlorinated sterilized samples. Overall, if turbidity increases under higher fungal diversity, bio-deterioration in groundwater-supplying facilities and public health problems could be intensified, regardless of chlorine treatment. In addition to fungal indicators and analyzing methods, physical hydrostatic treatment is necessary for monitoring and controlling fungal contamination.