• Journal of Microbiology and Biotechnology
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• v.17 no.1
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• pp.176-179
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• 2007

An electron paramagnetic resonance (EPR) signal characteristic of the 5,5'-dimethyl-l-pyrroline-N-oxide (DMPO)-OH spin adduct, which is formed from the reaction of DMPO with superoxide radicals generated by xanthine oxidasemediated reaction, was significantly reduced by the cadaverine or Escherichia coli Mn-containing superoxide dismutase (MnSOD). Likewise, cytochrome c reduction by superoxide was inhibited by cadaverine, and the inhibition level increased in proportion to the level of cadaverine. The cadA mutant of Vibrio vulnificus, which does not produce cadaverine because of the lack of lysine decarboxylase, exhibits less tolerance to superoxide stress in comparison with wild type. The results indicate that cadaverine scavenges superoxide radicals, and protects cells from oxidative stress.

• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.419-424
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• 2014

The pro-apoptotic BCL-2 family protein BID activates BAK and/or BAX, which form oligomeric pores in the mitochondrial outer membrane. This results in the release of cytochrome c into the cytoplasm, initiating the apoptotic cascade. Here, we utilized liposomes encapsulating sulfo-rhodamine at a controlled temperature to improve upon a previously reported assay system with enhanced sensitivity and specificity for measuring membrane permeabilization by BID-dependent BAK activation. BAK activation was inhibited by BCL-$X_L$ protein but not by a mutant protein with impaired anti-apoptotic activity. With the assay system, we screened a chemical library and identified several compounds including trifluoperazine, a mitochondrial apoptosis-induced channel blocker. It inhibited BAK activation by direct binding to BAK and blocking the oligomerization of BAK.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3681-3685
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• 2012

We developed a simple and effective method for the SERS-based detection of protein-small molecule complexes and label-free proteins using avidin-induced silver aggregation. Upon excitation with light of the appropriate wavelength (633 and 532 nm), the aggregated silver nanoparticles generate a strong electric field that couples with the resonance of the molecules (atto610 and cytochrome c), increasing the characteristic signals of these molecules and resulting in sensitive detection. The detection limit of biotin with the proposed method is as low as 48 ng/mL. The most important aspect of this method is the induction of silver aggregation by a protein (avidin), which makes the silver more biocompatible. This technique is very useful for the detection of protein-small molecule complexes.

• Animal Systematics, Evolution and Diversity
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• v.34 no.4
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• pp.208-214
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• 2018

The genus Luidia belongs to the family Luidiidae in the order Paxillosida. It is a common littoral taxon, and the depth range of the Korean fauna is generally 0-100 m. However, specimens of Luidia were collected from Jeju Island in Korea at 150-160 m depth and identified as Luidia sagamina sagamina $D{\ddot{o}}derlein$, 1920. This species is determined by morphological characteristics and mitochondrial cytochrome c oxidase subunit I sequence analysis. Luidia sagamina sagamina is a very rare sea star in worldwide and it only collected previously from Sagami Bay, Japan, and is newly reported in Korea. Four species of Luidia, including L. s. sagamina, are recorded in the Korean fauna.

• Animal Systematics, Evolution and Diversity
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• v.36 no.3
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• pp.222-227
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• 2020

In this study, we identified three monogonont rotifers from South Korea: Kellicottia bostoniensis (Rousselet, 1908), Trichocerca tenuior (Gosse, 1886), and Lepadella triptera (Ehrenberg, 1830). The distribution records of K. bostoniensis were mainly located in the Nearctic, Neotropic and Western Palearctic regions. After Japan, this is the second record of it in Asia. Trichocerca tenuior and Lepadella triptera have already been recorded in Korea, but the data of two species were insufficient in previous study. Here, we describe the morphological characteristics of the three species and the trophi structures of K. bostoniensis and T. tenuior. This study is the first to characterize the trophi structure of K. bostoniensis, observed using a scanning electron microscope. In addition, we have determined the partial cytochrome c oxidase subunit 1 (COI) and 18S rRNA gene sequences of T. tenuior and L. triptera for their DNA barcodes.

• Animal Systematics, Evolution and Diversity
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• v.35 no.3
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• pp.105-113
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• 2019

Feather mites comprise two superfamilies(Analgoidea and Pterolichoidea) and are highly specialized ectosymbionts of birds. To date, this group contains more than 2,500 species worldwide. Fifty-five feather mite species have been reported in Korea, and only one species of genus Alloptes has been recorded from black-tailed godwit Limosa limosa. Three new records of feather mites from the L. limosa in Korea are added in this study: Avenzoaria punctata Gaud, 1972, Bregetovia limosae (Buchholz, 1869), and Montchadskiana buchholzi (Canestrini, 1878). The genus Bregetovia Dubinin, 1951 is also new report for this country. In this paper, we provide the morphological descriptions and illustrations based on the present specimens. Additionally, we determined partial sequences of the mitochondrial cytochrome c oxidase subunit I(COI) from three feather mites as DNA barcodes.

• Animal Systematics, Evolution and Diversity
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• v.35 no.2
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• pp.84-90
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• 2019

The brittle star, Amphistigma minuta H.L. Clark, 1938, was collected from Munseom Island, Jeju-do, Korea, by SCUBA diving. This species has distinct morphological features, as follows: a small disk with large papillae on the disk margin; slender arms and four arm spines at proximal; and oral parts the same as those of the genus Amphipholis. Additionally, we obtained partial sequences of the cytochrome c oxidase subunit I gene (COI) (513 bp) and compared them with sequences from Australian A. minuta and 13 other species of Amphiuridae. As a result, intraspecific pairwise distance was 0.4% between two Korean individuals and intraspecific distance between the Australian and the Korean populations was 2.6-2.8%, which indicates they should be considered as the same species. Ultimately, 15 species of the family Amphiuridae have currently been recorded in Korea, including A. minuta.

• Journal of Species Research
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• v.10 no.4
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• pp.392-404
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• 2021

Rotifers collected from mosses, leaf litter, soil, and wetland at six different locations in Korea were investigated. Ten species belonging to six genera in four families of monogonont and bdelloid rotifers were new to Korea: Habrotrocha scepanotrochoides De Koning, 1947, H. tripus (Murray, 1907), Lecane opias (Harring and Myers, 1926), L. perpusilla (Hauer, 1929), Macrotrachela decora (Bryce, 1912), Otostephanos auriculatus auriculatus(Murray, 1911), O. torquatus amoenus Milne, 1916, Scepanotrocha corniculata Bryce, 1910, S. simplex De Koning, 1947, and Testudinella brevicaudata Yamamoto, 1951. Among these 10 Korean new records, Habrotrocha scepanotrochoides, H. tripus, Macrotrachela decora, Otostephanos auriculatus auriculatus, O. torquatus amoenus, Scepanotrocha corniculata, and S. simplex were new to Asia as well. The present study is the first report of the genus Scepanotrocha Bryce, 1910 from Korea. Here, diagnostic characteristics and photomicrographs are provided for each Korean new record. In addition, a partial sequence of mitochondrial cytochrome c oxidase subunit 1 gene (mtCOX1) for S. simplex is presented.

• Animal Systematics, Evolution and Diversity
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• v.38 no.2
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• pp.51-58
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• 2022

Four monogonont rotifers, Filinia hofmanni Koste, 1980, Lecane pusilla Harring, 1914, Mikrocodides chlaena (Gosse, 1886), and Proales fallaciosa Wulfert, 1937, were newly recorded in Korea. The genera Mikrocodides Bergendal, 1892 and Proales Gosse, 1886 were recorded for the first time in Korea. Mikrocodides chlaena and Proales fallaciosa were found from soil samples and are both soft-bodied species. Filinia hofmanni has previously been recorded mainly in Europe, and this is its first record in Asia. Lecane pusilla is the 24th lecanid rotifer recorded in Korea, and its morphological characteristics are consistent with previous research of L. pusilla. We have provided the morphological diagnoses of the four Korean specimens in this study, along with the partial sequences of mitochondrial cytochrome c oxidase subunit I(COI) gene of three species.

• Biomolecules & Therapeutics
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• v.12 no.2
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• pp.85-91
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• 2004

In all attempt to elucidate the role of apoptosis in drug resistance, cisplatin-resistant human chronic myelogenous leukemia (CML) K562 cells (K562/CDDP) were established and compared with drug sensitive parent cells (K562) in the induction of apoptosis. K562/CDDP cells were 5-fold more resistant to cisplatin compared to K562 cells. In addition, K562/CDDP cells were significantly more resistant to apoptois as judged by DNA fragmentation and DAPI staining. K562/CDDP cells exhibited decreased proleolytic activity of caspase-3 and this was further demonstrated by decreased cleavage of its substrate poly (ADP-ribose) polymerase (PARR- Western blot analysis showed that K562/CDDP cells had longer sustained levels of BCL-$X_L$ whereas no difference was noted in the level of Bcl-2. the translocation of Bax to mitochondria was significantly delayed in K562/CDDP cells. These results suggest that the reduced translocation of Bax and the sustained expression of BCL-$X_L$ may cause resistance to apoptosis through prevention of mitochondria release of cytochrome c, which subsequently induces reduction of caspase-3 activity and that this response is partly responsible for the acquired resistance to cisplatin ill K562 cells.