• Journal of Microbiology and Biotechnology
• /
• 제16권2호
• /
• pp.193-199
• /
• 2006

Halotolerant spore-forming Gram-positive bacteria were isolated from the root, rhizosphere, and non-rhizosphere soil of Blutaparon portulacoides. The different isolates were characterized genetically using an amplified ribosomal DNA restriction analysis (ARDRA), and phenotypically based on their colonial morphology, physiology, and nutritional requirements. Three different 16S rRNA gene-based genotypes were observed at a 100% similarity using the enzymes HinfI, MspI, and RsaI, and the phenotypic results also followed the ARDRA groupings. Selected strains, representing the different ARDRA groups, were analyzed by 16S rDNA sequencing, and members of the genera Halobaeillus, Virgibacillus, and Oceanobacillus were found. Two isolates showed low 16S rDNA sequence similarities with the closest related species of Halobacillus, indicating the presence of new species among the isolates. The majority of the strains isolated in this study seemed to belong to the species O. iheyensis and were compared using an AP-PCR to determine whether they had a clonal origin or not. Different patterns allowed the grouping of the strains according to Pearson's coefficient, and the resulting dendrogram revealed the formation of two main clusters, denoted as A and B. All the strains isolated from the soil were grouped into cluster A, whereas cluster B was exclusively composed of the strains associated with the B. portulacoides roots. This is the first report on the isolation and characterization of halotolerant spore-forming Gram-positive bacteria that coexist with B. portulacoides. As such, these new strains may be a potential source for the discovery of bioactive compounds with industrial value.

• Mycobiology
• /
• 제47권4호
• /
• pp.457-465
• /
• 2019

MonA is a subunit of a guanine nucleotide exchange factor that is important for vacuole passing and autophagy processes in eukaryotes. In this study, we characterized the function of MonA, an orthologue of Saccharomyces cerevisiae Mon1, in the model fungus Aspergillus nidulans and a toxigenic fungus A. flavus. In A. nidulans, the absence of AnimonA led to decreased fungal growth, reduced asexual reproduction, and defective cleistothecia production. In addition, AnimonA deletion mutants exhibited decreased spore viability, had reduced trehalose contents in conidia, and were sensitive to thermal stress. In A. flavus, deletion of AflmonA caused decreased fungal growth and defective production of asexual spores and sclerotia structures. Moreover, the absence of monA affected vacuole morphology in both species. Taken together, these results indicate that MonA plays conserved roles in controlling fungal growth, development and vacuole morphology in A. nidulans and A. flavus.

• 식물분류학회지
• /
• 제39권3호
• /
• pp.135-142
• /
• 2009

엽록체 rbcL gene의 염기서열과 포자의 형태를 바탕으로 고사리삼과 식물의 계통과 제주고사리삼속의 계통학적 위치를 추정하였다. 엽록체 DNA rbcL 염기서열의 분석 결과 고사리삼과는 뚜렷하게 고사리삼계보 (Botrychioid lineage)와 나도고사리삼계보 (Ophioglossoid lineage)의 두 군으로 구분되었다. 고사리삼계보에 있어 제주고사리삼속(Mankyua)은 Helmintostachys속과 함께 분계의 기저에서 고사리삼속(Botrychium)의 자매분류군으로 분지하였으나, 이들 고사리삼속(Botrychium), 제주고사리삼속(Mankyua), 및 Helmintostachys속 사이의 계통적 유연관계는 결정되지 못했다. 고사리삼속의 경우 Sceptridium아속과 Botrychium아속이 뚜렷한 단계통을 형성하였으나, Botrypus아속에 속한 분류군들은 고사리삼속의 기저에서 다른 고사리삼속 분류군의 자매분류군으로 분지하면서 단계통이 아닌 것으로 밝혀졌다. 나도고사리삼계보를 형성하는 나도고사리삼속(Ophioglossum)의 경우, Ophioglossum아속은 단계통을 형성하였으며, Ophioglossum아속에 대해 Cheiroglossa아속 및 Ophioderma 아속이 차례로 자매분류군으로 분지하였다. 염기서열 계통수, 포자의 형태 및 외부형태의 고찰에 있어 제주고사리삼속은 Helminthostachys와 유사하지만, 계통수에서 patristic distance 뿐 아니라 포자소엽의 형태가 뚜렷이 구분되어 이들 2속은 독립된 속으로 판단된다.

• 한국미생물·생명공학회지
• /
• 제19권3호
• /
• pp.296-302
• /
• 1991

소나무 숲 토양에서 방선균을 666주 선별한 후 이중 glucose isomerase 생산성이 우수하고 (488U/ml) 40 포도당액의 이성화율이 5%3에 도달하는 TH34 균주를 선별하였다. 이 균주는 세포벽을 구성하는 diaminopimelic acid(DAP), 기균사의 색깔, spiral type의 spore 사슬의 형태, melanoid 색소형성, 탄수화물 이용성 및 전자현미경 사진등으로 미루어 보아 Streptomyces luteogriseus로 동정하였다. 분리 동정한 S.luteogriseus의 발효조건 및 배지조성 등을 검토하여 본 결과 28~$29^{\circ}C$에서 효소생산이 최대이었으며 pH 6.0~8.0의 넓은 범위에서 안정한 효소생산을 보였다.

• Mycobiology
• /
• 제31권2호
• /
• pp.81-85
• /
• 2003

Antifungal properties of methyl 2-benzimidazole carbamate(BMC) were investigated using 16 fungi. Cytotoxicity test of BMC revealed that the morphology of HeLa cells was considerably deformed even at the concentrations as low as 0.1 ppm. Minimum inhibitory concentration(MIC) values of BMC for 7 fungi among the 16 tested ones were lower than $1.95{\times}10^{-4}{\mu}g/ml$, while Aspergillus flavus showed an MIC value higher than 1.0 ${\mu}g/ml$. Tolerance induction against BMC was successful only for Paecilomyces farinosus LAR10, contrary to the expectation that tolerance would be induced for the fungi having high MIC values such as Aspergillus niger ATCC 9642 and A. flavus ATCC 9643. Spore germination of A. niger ATCC 9642 was suppressed by BMC. However the mycelial growth of the fungus once germinated was not retarded at all by BMC up to 8 MIC. Addition of lanosterol provided a remedy for the reduced germination rate of A. niger ATCC 9642 spores.

• 한국식물병리학회:학술대회논문집
• /
• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
• /
• pp.117.2-117
• /
• 2003

The importance and diversity of the genus Stemphylium highlights the need for accurate identification of species. However, many Stemphylium isolates have been misidentified due to the use of spore size as the only identifying character. Molecular phylogenetic analyses were performed on fifty-four isolates covering 9 Stemphylium species collected in Korea. Phylogenetic analysis of the translation elongation factor -1 alpha (EF-1) and the calmodulin gene sequence data showed that Stemphylium species were segregated into seven distinct groups, most of w hichcorrelated with species identified by morphology. Analysis of EF-1 in particular was useful for establishing well- supported relationships among the species of Stemphylium.

• ALGAE
• /
• 제20권4호
• /
• pp.295-298
• /
• 2005

The growth of subaerial microalgae on historic buildings or various cultural properties causes discoloration and physico-chemical deterioration of the surfaces. We collected a subaerial chlorophyte, Chlorella sp., from the stone Standing Buddha statue at Jungwon Miruksazi, which is a national treasure of Korea, and found dormant, thickwalled spores with regular pentagonal ornamentation along with the vegetative Chlorella cells. The morphology of Chlorella resting spores was compared to that of the other green algal resting cells. The ornamented spores and smooth-walled vegetative cells revived in 2 weeks in a liquid freshwater medium and started reproduction by autospores. To our knowledge, the ability of Chlorella to form ornamented dormant spores in drought condition was not previously recorded. The ornamentation of spores would supplement taxonomic characteristics of this genus.

• Journal of Microbiology and Biotechnology
• /
• 제7권4호
• /
• pp.278-281
• /
• 1997

Streptomyces sp. MCY-846 selected by in vitro cytotoxicity assay produced elaiophylin. Individual characteristics of the strains such as spore morphology, and physiological characteristics indicated that the strain is resembled to Streptomyces hygroscopicus. The time course of cell growth and antibiotic production was observed in the medium containing 0.5% trehalose and 0.5% soybean meal as carbon and nitrogen sources, respectively. The optimum production of elaiophylin was tested with different combinations of carbon and nitrogen sources and reached a maxima of $470{\mu}$/ml in the PC-II medium.

• 한국어병학회지
• /
• 제19권1호
• /
• pp.1-6
• /
• 2006

Numerous large whitish cysts were found on the scale of wild mullet, Mugil cephalus captured in Jin-Hae bay of southern coastal sea of Korea. The cyst consisted of many trophozoites, mature spores and interstitial tissues of host origin. Spores were 8.25 ㎛ (7.26-9.35) in length, 6.3 ㎛ (5.63-6.78) in width, 4.34 ㎛ (3.96-5.04) in thickness. Polar capsules were 4.45㎛ (3.8-5.4) in length and 2.35 ㎛ (1.62-2.86) in width, and the length of polar filament was about 39.57 ㎛ (26.3-56.33). Based on the spore morphology and the host & tissue specificity, the present specimens were identified as Myxobolus episquamalis Egusa, Maeno & Sorimachi, 1990. Deformation of bony plate of the scales and infiltration of inflammatory cells were observed in the histological sections.

• 한국균학회지
• /
• 제16권4호
• /
• pp.230-234
• /
• 1988

Ganoderam lucidum은 비자실체성(非子實體性) 담자포자(擔子胞子)를 형성(形成)하여 다른 담자균류(擔子菌類)에서 볼 수 없는 특이(特異)한 생활환(生活環)을 보였다. G. lucidum은 배지상(培地上)의 기중균사(氣中菌絲)에서 Basidial strom상(狀)의 균사조직(菌絲組織)을 형성(形成)하고 조직표면(組織表面)에 있는 균사(菌絲)의 정단세포(頂端細胞)가 담자기(擔子器)로 분화(分化)되어 그 위에 비자실체성(非子實體性) 담자포자(擔子胞子)를 형성(形成)하였다. 자실체(子實體)없이 Basidial stroma에서 형성(形成)된 비자실체성(非子實體性) 담자포자(擔子胞子)는 정상 담자포자(擔子胞子)와 유사한 형태(形態)를 보이고 있었으나 크기가 약간 작고 포자표면(胞子表面)의 hollow수(數)가 현저히 적었다. 비자실체성(非子實體性) 담자포자(擔子胞子)의 형성(形成)은 균(菌)의 계통(系統)에 따라 뚜렷한 차이(差異)를 보였고 광(光) 및 환기조건하(換氣條件下)에서만 형성(形成) 되었으며 배지(培地)에 따른 차이(差異)는 거의 없었다.