• 제목/요약/키워드: r-DNA

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김치의 저온 발효 중 미생물 변화 양상 (Change of Microbial Communities in Kimchi Fermentation at Low Temperature)

  • 박정아;허건영;이정숙;오윤정;김보연;민태익;김치경;안종석
    • 미생물학회지
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    • 제39권1호
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    • pp.45-50
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    • 2003
  • 분자 생물학적 방법 인 DGGE를 이용하여 저온에서 김치가 발효되는 동안 관여하는 미생물의 다양성과 변화양상을 분석하였다. 김치를 저온 ($4^{\circ}C$)에서 발효시키는 60 일 동안 5 일 마다 시료를 채취하였으며, 채취한 김치 시료에서 genomic DNA를 추출하여 실험을 수행하였다. 김치 시료 genomic DNA로부터 16S rDNA의 V3영역을 증폭하여 DGGE를 수행한 결과에서 관찰된 amplicon들의 염기서열을 분석한 결과 저온에서 김치가 발효되는 동안 젖산균들이 주요 미생물 군집으로 나타났으며, 그 중에서도 Weissella koreensis가 발효 전 과정 동안, Lactobacillus sakei의 경우는 발효 10 일째부터, 그리고 Leuconostoc gelidurn은 발효30 일째부터 amplicon들의 농도가 진하게 나타나 이들이 저온에서 김치 발효 과정 동안의 우점종 균주들 임을 알 수 있었다.

Phylogenetic Relationships among Diverse Dinoflagellate Species Occurring in Coastal Waters off Korea Inferred from Large Subunit Ribosomal DNA Sequence Data

  • Kim, Keun-Yong;Kim, Chang-Hoon
    • ALGAE
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    • 제22권2호
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    • pp.57-67
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    • 2007
  • We analyzed the nuclear-encoded large subunit ribosomal RNA gene (LSU rDNA) sequences of 19 dinoflagellates occurring in costal waters off Korea and reconstructed a phylogenetic tree containing 74 representative species from 37 distinct genera. Of these, the LSU rDNA sequences of Amylax triacantha (Jörgensen) Sournia, Gonyaulax verior Sournia (= Amylax diacantha Meunier), Gyrodinium fissum (Levander) Kofoid et Swezy, Katodinium glaucum (Lebour) Lebour III, Noctiluca scintillans (Macartney) Kofoid et Swezy, Oxyphysis oxytoxoides Kofoid, and Pyrophacus steinii (Schiller) Wall et Dale are reported for the first time. Our LSU rDNA tree consistently placed Oxyrrhis marina Dujardin and N. scintillans at the most primitive positions, giving rise to a strongly supported monophyletic group of typical dinoflagellate species belonging to the Dinophyceae. The phylogenetic relationships among the typical dinoflagellates, however, were not resolved in the higher taxonomic levels in general. Only genera at terminal branches were usually supported with high confidence. The Dinophysiales, represented by Dinophysis species and O. oxytoxoides, formed a strongly supported monophyletic assemblage. The Gymnodiniales and Peridiniales were recovered as polyphyletic groupings. Members of the Gonyaulacales were consistently grouped together, but lacked statistical support. Within this order, the Ceratiaceae and Goniodomataceae each formed a monophyletic group, but the Gonyaulacaceae was polyphyletic. The phylogenetic relationships of the Gonyaulacaceae were generally congruent with differences in the combinations of the apical pore complex, hypothecal organization and thecal formula.

Evaluation of taxonomic validity of four species of Acanthamoeba: A. divionensis, A. paradivionensis, A. mauritaniensis, and A. rhysodes, inferred from molecular analyses

  • LIU Hua;MOON Eun-Kyung;YU Hak-Sun;JEONG Hae-Jin;HONG Yeon-Chul;KONG Hyun-Hee;CHUNG Dong-Il
    • Parasites, Hosts and Diseases
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    • 제43권1호
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    • pp.7-13
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    • 2005
  • The taxonomy of Acanthamoeba spp., an amphizoic amoeba which causes granulomatous amoebic encephalitis and chronic amoebic keratitis, has been revised many times. The taxonomic validity of some species has yet to be assessed. In this paper, we analyzed the morphological characteristics, nuclear 18s rDNA and mitochondrial 16s rDNA sequences and the Mt DNA RFLP of the type strains of four Acanthamoeba species, which had been previously designated as A. divionensis, A. parasidionensis, A. mauritaniensis, and A. rhysodes. The four isolates revealed characteristic group II morphology. They exhibited 18S rDNA sequence differences of $0.2-1.1\%$ with each other, but more than $2\%$ difference from the other compared reference strains. Four isolates formed a different clade from that of A. castellanii Castellani and the other strains in morphological group lion the phylogenetic tree. In light of these results, A. paradivionensis, A. divionensis, and A. mauritaniensis should be regarded as synonyms for A. rhysodes.

Characterization of Sclerotinia sclerotiorum Isolated from Paprika

  • Jeon, Young-Jae;Kwon, Hyuk-Woo;Nam, Ji-Sun;Kim, Seong-Hwan
    • Mycobiology
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    • 제34권3호
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    • pp.154-157
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    • 2006
  • A fungal isolate collected from infected paprika (Capsicum annuum var. grossum) was characterized as Sclerotinia sclerotiorum based on its ability of sclerotium formation, physiological and molecular properties. When the isolate was grown on potato dextrose agar, oatmeal agar, and malt extract agar, it grew most well on PDA. Optimal temperature and pH for its growth were $25^{\circ}C$ and pH 7, respectively. The fungal isolate produced sclerotia on PDA within 10 days, and the color and shape of the sclerotia were similar to those of S. sclerotiorum. The ITS rDNA regions including ITS1 and ITS2 and 5.8S sequences were amplified using ITS1F and ITS4 primers from the genomic DNAs of the paprika isolate and other known pathogenic S. sclerotiorum isolated from different crops in Korea, and their nucleotide sequences were determined. Sequence comparison analysis showed the ITS rDNA of the paprika isolate shares 100% sequence identity with those of S. sclerotiorum isolated from red pepper, lettuce and a S. sclerotiorum isolate registered in GenBank DNA database. Neighbor joining analysis based on the ITS rDNA sequence revealed the paprika isolate has very close phylogenetic relationships with known Sclerotinia sclerotiorum isolates. This is the first report that S. sclerotiorum has been found associated with paprika rot in paprika growing countries.

Hc nuclear polyhedrosis virus DNA 제한효소절편의 molecular cloning 과 외래 유전자 발현 (Molecular cloning and foreign gene expression of restriction endonuclease fragments of the Hc nuclear polyhedrosis virus DNA)

  • 이근광
    • 한국어병학회지
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    • 제8권1호
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    • pp.31-36
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    • 1995
  • HcNPV DNA genome 을 제한효소 EcoRI 으로 절단하여 그들의 일부 절편을 pUC8 vector 에 cloning 한 후 E. coli JM 83 세포에 형질 전환시켰다. 이 결과 24 개의 EcoRI 절편중 12 개의 절편이 cloning 되었다. 이들 제조합체중 4 개는 eNP-O, eNP-Q, eNP-R, eNP-S 라 명명하였다. 또한 이들 제조합체의 외래 유전자 발현을 SDS-PAGE 에 의해 단백질 패턴을 분석하였다. 그 결과 제조합체 eNP-O, eNP-Q, eNP-R 에서는 E. coli JM 83 숙주세포의 단백질 밴드와 비교하여 다른 분자량을 갖는 밴드가 나타났다.

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청미래덩굴의 근권에서 분리된 2종의 Glomeromycota 미기록종 (Two Unreported Glomeromycota Fungi Isolated from Rhizospheres of Smilax china)

  • 박혁;가강현;엄안흠
    • 한국균학회지
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    • 제47권3호
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    • pp.275-280
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    • 2019
  • 청미래덩굴의 근권 토양을 온실에서 배양하여 Glomeromycota에 속하는 균류의 포자를 분리하였다. 분리된 포자는 18S partial rDNA 영역의 DNA 염기서열 분석과, 더 정확한 동정을 위해 추가적으로 ITS 영역과 28S rDNA 영역까지 포함하는 $Kr{\ddot{u}}ger$ fragment 지역의 염기서열을 분석하여 동정하였다. 동정 과정에서 2종의 국내 미기록종 Glomeromycota 균류의 포자를 확인하였으며, 확인된 종은 Diversispora eburnea, Paraglomus laccatum이다. 확인된 미기록종 포자의 형태적 특성 및 계통적 분석의 결과에 대해 기술하였다.

Transposable Elements Arrangement in Genome and Their Applications for Analysis of Evolutional Events

  • Maekawa, Hideaki
    • 한국잠사학회:학술대회논문집
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    • 한국잠사학회 2003년도 International Symposium of Silkworm/Insect Biotechnology and Annual Meeting of Korea Society of Sericultural Science
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    • pp.24-27
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    • 2003
  • The ribosomal RNA gene (rDNA) cluster was located in the nucleolus organizer and was genetically determined as one locus. We speculated by using sequence differences in the functional rDNA unit that the segregation time between Chinese and Japanese types of B. mandarina is about three million years ago. The differences of the amount of inserted non-LTR retrotransposons, R1Bm and R2Bm, in rDHA cluster were used for the identification of B.mori strains. (omitted)

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Vitamin과 핵산이 Sclerotium rolfsii의 균사생장 및 균핵형성에 미치는 영향 (Effects of Vitamins and Nucleic acids on the mycelial growth and the sclerotial production of Sclerotium rolfsii)

  • 김기청
    • 한국응용곤충학회지
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    • 제12권2호
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    • pp.71-78
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    • 1973
  • 목련흰비단병균 Sclerotium rolfsii의 균사생장 및 균핵형성에 대한 thianine, biotin, nicotinic acid, Pyrido-xine, inositol과 DNA 및 RNA의 영향을 조사한 바 그 결과를 요약하면 다음과 같다. 1. 공시균은 thiamine 결핍균으로서 균사생장 최적 thiamine 농도는 20r/l이고 이농도를 초과하면 오히려 균사생장이 억제되어 150r/l에서는 무첨가구와 거이 비슷한 균사생장을 하였다. 2. 공시균의 생장에 있어서 thiamine의 첨가에 따른 질소원 이용도는 $NH_4NO_3>(NH_4)_2SO_4>asparagine>KNO_3$의 순위이며 질소원별 thiamine 최적요구량은 $KNO_3$인 경우 12r/l, asparagine인 경우는 16r/l정도였다. 균핵형성량에 있어서는 $KNO_3>NH_4NO_3>asparagine>(NH_4)_2SO_4$의 순위로 질소원별 thiamine 최적량은 $KNO_3,\;NNO_3,\;NH_4NO_3$가 8r/l에서 균핵의 대부분이 형성되나 asparagine은 16r/l정도였다. 3. 배양액의 pH는 공시균이 생장을 개시하자마자 3.5정도로 급격히 떨어지나 그 이후로는 생장량이 증가함에 따라 완만하게 떨어졌다. 그러나 pH2.2 이하로는 내려가지 않았다. 4. Nicotinic acid는 공시균의 생장 및 균핵형성에 아무런 효과가 없었다. 그러나 thiamine 10r/l와의 공존하에서는 다소의 효과가 있는 것으로 nicotinic acid 7-10mg/l에서 가장 생장이 좋았고 그 이상에서는 생육이 억제되었다. 5. Pyridoxine, biotin 및 inositol은 배지의 질소원이 $(NH_4)_2SO_4$나 asparagine인 경우 모두 공시균의 균사생장 및 균핵형성에 아무런 효과가 없었다. 6. 공시균의 균사생 장에 대한 각종 vitamin의 상호효과는 thiamine, biotin, Pyridoxine, inositol의 4가지 combination에 의해서도 thiamine이 첨가되지 않으면 거이 효과가 나타나지 않았다. 그러나 thiamine+pyridoxine, thiamine + inositol, thiamine + biotin + pyrid oxine, thiamine + biotin + pyridoxine + inositol 구에 있어서는 thiamine단독첨가구와 동등 혹은 그 이상이지만 thiamine+biotin과 thianline+biftin+inositol구는 오히려 떨어졌다. 균핵형성에 있어서는 thiamine단독구에 비하여 각구 모두 약간씩 증가하였다. 7. 공시균의 균사생장에 대한 DNA와 RNA의 효과는 무첨가구에 비하여 다소 인정되는데 DNA보다는 RNA가 좀더 효과적이었다. RNA는 2-6mg/l에서 DNA는 6mg/l에서 가장 좋았다. 균핵형성에 있어서는 효과가 없 었다. 8. RNA의 농도가 증가함에 따라 또 thiamine의 농도가 증가함에 따라 균사생장량이 증가하는 것으로 thiamine의 존재하에 RNA의 효과가 뚜렷하게 나타났다. 그러나 균핵형성에는 효과가 없었다.

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Optimization of DNA Extraction from a Single Living Ciliate for Stable and Repetitive PCR Amplification

  • Kim, Se-Joo;Min, Gi-Sik
    • Animal cells and systems
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    • 제13권3호
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    • pp.351-356
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    • 2009
  • Ciliates are undoubtedly one of the most diverse protozoans that play a significant role in ecology. However, molecular examination, based on comparing the DNA sequences, has been done on a limited number of the species. Because most ciliates are uncultivable and their population sizes are often too small, it is usually difficult to obtain sufficient genomic DNA required for PCR based experiments. In the present study, we evaluated the effectiveness of four commercial DNA extraction procedures that extract high quality genomic DNA from a single ciliate cell. It was discovered that RED Extract-N-$Amp^{TM}$ PCR kit is the best method for removing PCR-inhibiting substances and minimizing DNA loss during purification. This method can also amplify more than 25 reactions of PCR. In addition, this technique was applied to single cells of 19 species belonged to 7 orders under 5 classes that isolated from mixed natural populations. Their small subunit ribosomal DNA (SSU rDNA) was successfully amplified. In summary, we developed a simple technique for the high-yield extraction of purified DNA from a single ciliate cell that may be more useful for rare ciliates, such as tiny and uncultivable marine microbes.

Non-invasive Biological Monitoring of DNA Adducts Formed at Workers Handling 3,3-Dichlorobenzidine(DCB) by Using GC/MS

  • Lee, Jin-Heon
    • 한국환경보건학회지
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    • 제29권4호
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    • pp.21-26
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    • 2003
  • We examine the metabolites(DCB and acetyl DCB) extracted from exfoliated urothelial cells of 33 workers who employed DCB-handling industries. The characteristics of workers submitted urine, whose age, working years and smoking persons were 41.9$\pm$11.1, 8.7$\pm$5.5 and 25(32.0%), respectively. DNA adduct was isolated from the exfoliated urothelial cells by applying $^{32}$ p-postlabeling procedure. Metabolites(DCB and acetyl DCB) were extracted from DNA adducts by hydrolyzing and N-glycosylase. Concentrations of DCB and acetyl DCB were 28.6$\pm$5.25 ng/g DNA, and 17.0$\pm$3.73 ng/g DNA, respectively. The regression between DCB level and exposure years of workers is y = 1.668 + 2.588x(p = 0.005, $r^2$= 0.394). The regression between acetyl DCB level and exposure years of workers is y = 8.071 + 1.325x(p = 0.076, $r^2$= 0.222). Smoking workers are significantly higher than non-smoking workers on DCB and acetyl DCB level(p = 0.065 and 0.021, respectively). DCB level was 33.9$\pm$7.14 ng/g DNA on smokers, and 23.1$\pm$9.97 ng/g DNA on non-smokers. Acetyl DCB was 25.1$\pm$5.27 ng/g DNA on smokers, and 8.92$\pm$7.22 ng/g DNA on non-smokers.