• 제목/요약/키워드: biological

검색결과 33,941건 처리시간 0.053초

Synthesis and Physicochemical Properties of Ionic Liquids: 1-Alkenyl-2,3-dimethylimidazolium Tetrafluoroborates

  • Min, Gwan-Hong;Yim, Tae-Eun;Lee, Hyun-Yeong;Kim, Hyo-Jin;Mun, Jun-Young;Kim, Sang-Mi;Oh, Seung-M.;Kim, Young-Gyu
    • Bulletin of the Korean Chemical Society
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    • 제28권9호
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    • pp.1562-1566
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    • 2007
  • 1-Alkenyl-2,3-dimethylimidazolium tetrafluoroborate ionic liquids having an olefinic substituent were synthesized and characterized. Among them, [AMMIm]BF4 with an allyl group showed lower viscosity, higher ionic conductivity, and a wider electrochemical window compared with its analogue having a saturated alkyl substituent. An EDLC with [AMMIm]BF4 showed better performance than that with [PMMIm]BF4, too.

Discovery of Two Chrysosporium Species with Keratinolytic Activity from Field Soil in Korea

  • Gurung, Sun Kumar;Adhikari, Mahesh;Kim, Sang Woo;Bazie, Setu;Kim, Hyun Seung;Lee, Hyun Goo;Kosol, San;Lee, Hyang Burm;Lee, Youn Su
    • Mycobiology
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    • 제46권3호
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    • pp.260-268
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    • 2018
  • In an ongoing survey of Korean indigenous fungi, two fungal strains (KNU16-74 and KNU16-99) belonging to the genus Chrysosporium were isolated from field soil in Gyeongnam, Korea. Morphological characterization and phylogenetic analysis using sequence of the internal transcribed spacer regions were carried out to confirm its precise identification. These strains were identified as Chrysosporium indicum (KNU16-74) and Chrysosporium fluviale (KNU16-99). To examine the keratin degradation efficiency of these two fungal species, human hair strands were incubated with fungus culture. Results revealed that these two fungal species have the ability to degrade keratin substrate. This is the first report of these two species in Korea.

Cloning and Sequencing of the ${\beta}-Amylase$ Gene from Paenibacillus sp. and Its Expression in Saccharomyces cerevisiae

  • Jeong, Tae-Hee;Kim, Hee-Ok;Park, Jeong-Nam;Lee, Hye-Jin;Shin, Dong-Jun;Lee, Hwang-Hee Blaise;Chun, Soon-Bai;Bai, Suk
    • Journal of Microbiology and Biotechnology
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    • 제11권1호
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    • pp.65-71
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    • 2001
  • A gene from Paenibacillus sp. KCTC 8848P encoding ${\beta}-amylase$ was cloned and expressed in Escherichia coli. The Paenibacillus ${\beta}-amylase$ gene cosisted of a 2,409-bp open reading frame without a translational stop codon, encoding a protein of 803 amino acids. The presumed ribosime-binding site, GGAGG, was located 10 bp upstream from the TTG initiation codon. The deduced amino acid sequence of the ${\beta}-amylase$ gene had a 95% similarity to the ${\beta}-amylase$ of Bacillus firmus. The ${\beta}-amylase$ gene was introduced into wild-type strains of Saccharomyces cerevisiae using a linearized yeast integrating vector containing a geneticin resistance gene and its product was secreted into the culture medium.

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Three New Records of Mortierella Species Isolated from Crop Field Soil in Korea

  • Yadav, Dil Raj;Kim, Sang Woo;Adhikari, Mahesh;Um, Yong Hyun;Kim, Hyun Seung;Kim, Changmu;Lee, Hyang Burm;Lee, Youn Su
    • Mycobiology
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    • 제43권3호
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    • pp.203-209
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    • 2015
  • Three new fungal species of the genus Mortierella, Mortierella zychae, Mortierella ambigua, and Mortierella indohii, have been reported in Korea. The fungi were encountered during a study on the fungal community of soil samples collected from different locations in Korea. The species were identified based on molecular and morphological analyses. This study presents detailed descriptions of the morphological observations and molecular phylogenetic analysis of these three fungi. All three species were found to be sensitive to triphenyltetrazolium chloride staining. M. zychae demonstrated the highest intensity of mycelial staining, indicating that this species has the highest potential to produce arachidonic acid of the three species. The staining results indicated that the newly recorded species could potentially be useful for arachidonic acid production.

First report of six Sordariomycetes fungi isolated from plant litter in freshwater ecosystems of Korea

  • Goh, Jaeduk;Mun, Hye Yeon;Jeon, Yu-Jeong;Chung, Namil;Park, Young-Hwan;Park, Sangkyu;Hwang, Hyejin;Cheon, Wonsu
    • 한국균학회지
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    • 제48권2호
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    • pp.103-116
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    • 2020
  • Freshwater ecosystems provide a complex environment for microorganisms. In this study, we isolated diverse fungal strains from plant litter in freshwaters. These strains were identified using molecular phylogenetic analyses of rDNA and/or other gene sequences (TUB, GAPDH, and EF1). In addition, we examined their morphological characteristics by microscopy and cultural characteristics on several media. We identified six previously unrecorded Sordariomycetes species in Korea, i.e., Colletotrichum godetiae, Discosia rubi, Robillarda sessilis, Monochaetia dimorphospora, Idriella lunata, and Phialemoniopsis endophytica. Of these, D. rubi and M. dimorphospora exhibited high extracellular amylase, lipase, and protease activities, suggesting that these fungal isolates might play an important role as decomposers in freshwater ecosystems. Plant litter could thus be a good source for isolating and investigating previously undocumented fungal species in freshwater environments.

Expression and phosphorylation analysis of soluble proteins and membrane-localised receptor-like kinases from Arabidopsis thaliana in Escherichia coli

  • Oh, Eun-Seok;Eva, Foyjunnaher;Kim, Sang-Yun;Oh, Man-Ho
    • Journal of Plant Biotechnology
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    • 제45권4호
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    • pp.315-321
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    • 2018
  • Molecular and functional characterization of proteins and their levels is of great interest in understanding the mechanism of diverse cellular processes. In this study, we report on the convenient Escherichia coli-based protein expression system that allows recombinant of soluble proteins expression and cytosolic domain of membrane-localised kinases, followed by the detection of autophosphorylation activity in protein kinases. This approach is applied to regulatory proteins of Arabidopsis thaliana, including 14-3-3, calmodulin, calcium-dependent protein kinase, TERMINAL FLOWER 1(TFL1), FLOWERING LOCUS T (FT), receptor-like cytoplasmic kinase and cytoplasmic domain of leucine-rich repeat-receptor like kinase proteins. Our Western blot analysis which uses phospho-specific antibodies showed that five putative LRR-RLKs and two putative RLCKs have autophosphorylation activity in vitro on threonine and/or tyrosine residue(s), suggesting their potential role in signal transduction pathways. Our findings were also discussed in the broader context of recombinant expression and biochemical analysis of soluble and membrane-localised receptor kinases in microbial systems.

Seven Yeast Strains Isolated from Freshwaters for the First Record in Korea

  • Jeon, Yu Jeong;Park, Sangkyu;Hwang, Hyejin;Park, Yeong Hwan;Cheon, Wonsu;Goh, Jaeduk;Chung, Namil;Mun, Hye Yeon
    • 한국균학회지
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    • 제48권4호
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    • pp.523-531
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    • 2020
  • This study focused on the isolation and characterization of wild yeasts in Korea. The yeasts were identified by phylogenetically analyzing the D1/D2 domains of the 26S rDNA regions. Consequently, we identified seven strains, NNIBRFG856, NNIBRFG3732, NNIBRFG3734, NNIBRFG3738, NNIBRFG3739, NNIBRFG5497, and NNIBRFG6049, which were confirmed to be Kabatiella microsticta, Pichia membranifaciens, Candida vartiovaarae, Candida sake, Debaryomyces hansenii, Candida railenensis, and Schwanniomyces polymorphus, respectively, all of them being new in Korea. Morphological and cultural characteristics of these yeast species were investigated. None of the strains formed ascospores or pseudomycelia. Moreover, these yeasts grew in a pH range of 4-8. NNIBRFG3732, NNIBRFG3738, NNIBRFG3739, NNIBRFG5497, and NNIBRFG6049 were halotolerant or halophilic, and NNIBRFG3732, NNIBRFG3734, and NNIBRFG6049 grew in vitamin-free medium. NNIBRFG3732, NIBRFG3739, and NNIBRFG6049 grew at 35 ℃, but not at 40 ℃.

Isolation and Characterization of Eleven Unrecorded Pezizomycotina Species from Freshwater Ecosystems in Korea

  • Goh, Jaeduk;Jeon, Yu-Jeong;Mun, Hye Yeon;Chung, Namil;Park, Young-Hwan;Park, Sangkyu;Hwang, Hyejin;Cheon, Wonsu
    • 한국균학회지
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    • 제48권4호
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    • pp.423-443
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    • 2020
  • Freshwater fungi are a poly-phylogenetic group of taxonomically diverse organisms. In this study, we isolated diverse fungal strains from various environmental samples obtained from freshwaters in Korea. These strains were identified by performing molecular phylogenetic analyses of rDNA and/or other sequences (beta-tubulin, RNA polymerase II, and translation elongation factor 1). In addition, we examined their morphological characteristics microscopically and cultural characteristics using different media. We identified eleven unrecorded Pezizomycotina species: Cladosporium angulosum, Pseudorobillarda phragmitis, Paraconiothyrium estuarinum, Pseudopithomyces palmicola, Pyrenochaetopsis paucisetosa, Thelebolus globosus, Plagiostoma mejianum, Trichoderma cremeum, Fusarium tanahbumbuense, Coniochaeta endophytica, and Chaetomium tenue. Environmental samples obtained from different freshwater ecosystems in Korea could thus be a good source for isolating and investigating novel fungal species.

Melanogenesis Inhibitory Activity of Epicatechin-3-O-Gallate Isolated from Polygonum amphibium L.

  • Lee, Young Kyung;Hwang, Buyng Su;Hwang, Yong;Lee, Seung Young;Oh, Young Taek;Kim, Chul Hwan;Nam, Hyeon Ju;Jeong, Yong Tae
    • 한국미생물·생명공학회지
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    • 제49권1호
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    • pp.24-31
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    • 2021
  • This study aimed to investigate the melanogenesis inhibitory activity of epicatechin-3-O-gallate (ECG) isolated from Polygonum amphibium L. ECG was isolated from the ethanol extract of P. amphibium L, and its chemical structure was determined using spectroscopic methods such as LC-ESI-MS, 1D-NMR, and UV spectroscopy. ECG inhibited the melanogenesis of B16F10 cells in a dose-dependent manner. Particularly, it decreased the melanin content by 27.4% at 200 µM concentration, compared with the control, in B16F10 cells, without causing cytotoxicity. It is noteworthy that the expression of three key proteins, including tyrosinase, tyrosinase-related protein-1 (TRP-1), TRP-2, and microphthalmia-associated transcription factor (MITF), involved in melanogenesis, is significantly inhibited by ECG. The ECG isolated in this study caused the inhibition of body pigmentation and tyrosinase activity in vivo in the zebrafish model. These results suggest that the ECG isolated from P. amphibium L. is an effective anti-melanogenesis agent.