• 한국동물학회:학술대회논문집
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• 한국동물학회 1997년도 한국생물과학협회 학술발표대회
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• pp.266.2-266
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• 1997

No Abstract, See Full Text

• 한국산림과학회지
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• 제81권4호
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• pp.320-324
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• 1992

들메나무(Fraxinus mandshurica Rupr.) 는 우리나라에서 두가지의 서로 다른 형태(形態)가 자생(自生)하고 있는 것으로 알려져 있다. 최근(最近)에 개발(開發)된 PCR기법(技法)을 이용(利用)하여 이 두 형태(形態)의 들메나무 DNA의 변이(變異)를 조사(調査)하였다. DNA 합성(合成) 효소(酵素)와 인공합성(人工合成)된 primer를 이용(利用)하여 이 수종(樹種)의 DNA를 증폭(增幅)시켜 비교(比較)한 결과(結果)이 두 형태(形態)는 DNA 비례(排列)에서 서로 다른것으로 나타났다. DNA변이(變異)는 같은 형태내(形態內)의 개체간(個體間)에도 나타나나 각 형태별(形態別)로 뚜렷하게 구분(區分)되어 형태별(形態別)로 특징적(特徵的)인 band들이 관찰(觀察)되었다. 이러한 특징적(特徵的)인 band들로 두 형태(形態)를 구분(區分)할 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제20권10호
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• pp.1463-1470
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• 2010

E. coli has long been widely used as a host system for the manufacture of recombinant proteins intended for human therapeutic use. When considering the impurities to be eliminated during the downstream process, residual host cell DNA is a major safety concern. The presence of residual E. coli host cell DNA in the final products is typically determined using a conventional slot blot hybridization assay or total DNA Threshold assay. However, both the former and latter methods are time consuming, expensive, and relatively insensitive. This study thus attempted to develop a more sensitive real-time PCR assay for the specific detection of residual E. coli DNA. This novel method was then compared with the slot blot hybridization assay and total DNA Threshold assay in order to determine its effectiveness and overall capabilities. The novel approach involved the selection of a specific primer pair for amplification of the E. coli 16S rRNA gene in an effort to improve sensitivity, whereas the E. coli host cell DNA quantification took place through the use of SYBR Green I. The detection limit of the real-time PCR assay, under these optimized conditions, was calculated to be 0.042 pg genomic DNA, which was much higher than those of both the slot blot hybridization assay and total DNA Threshold assay, where the detection limits were 2.42 and 3.73 pg genomic DNA, respectively. Hence, the real-time PCR assay can be said to be more reproducible, more accurate, and more precise than either the slot blot hybridization assay or total DNA Threshold assay. The real-time PCR assay may thus be a promising new tool for the quantitative detection and clearance validation of residual E. coli host cell DNA during the manufacturingprocess for recombinant therapeutics.

• Journal of Microbiology and Biotechnology
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• 제6권2호
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• pp.142-144
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• 1996

To clone the gene coding for steroid $\Delta^1$-dehydrogenase of Arthrobacter simplex, its genomic library was constructed with a , $\lambda$gt11 expression vector and immunoscreened with antiserum against the enzyme. One positive clone was found to carry a 1.6-kb EcoR I restriction endonuclease fragment of A. simplex DNA. The restriction map of the 1.6-kb EcoR I fragment was determined after cloning of the DNA into pBS vector.

• Journal of Microbiology
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• 제42권4호
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• pp.305-314
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• 2004

An exopolysaccharide-producing microalgal dinoflagellate was isolated from a red-tide bloom and des­ignated strain KG03. A bacteria-free culture of strain KG03 was achieved using a modified wash with phototaxis and antibiotic treatment. Combined treatment with neomycin and cephalosporin was the most effective for eliminating the bacteria associated with the microalgae. Strain KG03 was identified as Gyrodinium impudicum by analyzing the ITS regions of the 5.8S rDNA, 18S rDNA, morphological phenotype and fatty acid composition. The exopolysaccharide production and cell growth in a 300-ml photobioreactor were increased 2.7- and 2.4-fold, respectively, compared with that in a flask culture at the first isolation step.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권2호
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• pp.83-88
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• 2003

A cellulose-producing strain isolated from rotten apples was identified as Gluconacetobacter hansenii based on its physiological properties and the 16S rDNA complete sequencing method, and specifically named Gluconacetobacter hansenii PJK. The amount of bacterial cellulose (BC) produced by G. hansenii PJK in a shaking incubator was 1.5 times higher than that produced in a static culture. The addition of ethanol to the medium during cultivation enhanced the productivity of bacterial cellulose, plus the supplementation of 1% ethanol into the culture medium made the produced BC aggregate into a big lump and thus protected the bacterial-cellulose-producing G. hansenii PJK cells in the shear stress field from being converted into non-cellulose-producing (Cel) mutants. Cells subcultured three times in a medium containing ethanol retained their ability to produce BC without any loss in the production yield.

• Mycobiology
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• 제40권4호
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• pp.255-257
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• 2012

Among 80 types of yeast isolated from wild flowers in Daejeon, Korea, two species that have not yet been identified by phylogenetic analysis of the internal transcribed spacer-2 (ITS2) genes and 26S rDNA sequences were identified as Candida sp. 44-C-1 and Cryptococcus sp. 9-D-1. Neither of the newly identified species formed ascospores, while Candida sp. 44-C-1 formed pseudomycelium and Cryptococcus sp. 9-D-1 did not.

• Mycobiology
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• 제39권3호
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• pp.226-229
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• 2011

An unrecorded Antrodia species was collected in South Korea and based on morphological characteristics, the species was identified as Antrodia sitchensis. To confirm its affinity within the polypores, the phylogenetic relationships of A. sitchensis and allied species were established using large subunit rDNA sequences.

• Animal Systematics, Evolution and Diversity
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• 제40권1호
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• pp.1-15
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• 2024

Our study aimed to investigate the diversity of tintinnid species in Korea by collecting samples from coastal waters. As a result, we identified and redescribed three newly recorded species of the genus Tintinnopsis Stein, 1867 and one previously recorded species of the genus Antetintinnopsis Wang et al., 2021 in Korea. The loricae morphology and molecular phylogeny based on the 18S rDNA sequences of these four were analyzed. Tintinnopsis kiaochowensis Yin, 1956 is characterized by having an irregular collar with spiral turns and an obconical-shaped bowl. Tintinnopsis orientalis Kofoid and Campbell, 1929 is characterized by the inverted bell-shaped lorica with size of 121-140×86-94 ㎛. Tintinnopsis parvula Jörgensen, 1912 is characterized by its narrower collar than bowl and acute angle of the bowl (39-75°). The recorded species, Antetintinnopsis gracilis (Kofoid and Campbell, 1929) Wang et al., 2021 is characterized by a cylindrical collar narrower than the bowl width and with a size of 98-131×37-46 ㎛.

• Journal of Microbiology and Biotechnology
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• 제25권10호
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• pp.1768-1771
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• 2015

Human Fen1 protein (hFen1) plays an important role in Okazaki fragment processing by cleaving the flap structure at the junction between single-stranded (ss) DNA and doublestranded (ds) DNA, an intermediate formed during Okazaki fragment processing, resulting in ligatable nicked dsDNA. It was reported that hChlR1, a member of the cohesion establishment factor family, stimulates hFen1 nuclease activity regardless of its ATPase activity. In this study, we found that cohesion establishment factors cooperatively stimulate endonuclease activity of hFen1 in in vivo mimic condition, including replication protein-A-coated DNA and high salt. Our findings are helpful to explain how a DNA replication machinery larger than the cohesion complex goes through the cohesin ring structure on DNA during S phase in the cell cycle.