• Journal of Dairy Science and Biotechnology
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• 제21권2호
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• pp.138-147
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• 2003

We here analyzed and proposed the structures of the N-linked sugar chains of PAS-7 from bovine milk fat globule membrane. The N-linked sugar chains were liberated from PAS-7 by hydrazinolysis and, after modifying the reducing ends with 2-aminopyridine (PA), were separated into one neutral (7N,55%) and two acidic (7M mono-, 43%; 7D, di-, 2%) sugar chain roups. The latter were converted into neutral groups (7MN and 7DN) by sialidase digestion. The structure of each of these PA-neutral sugar chains was determined by sugar analysis, sequential exoglycosidase digestion, partial acetolysis, and 1H-NMR spectroscopy. The results show that the 10 sugar chains were of the biantennary complex type with and without fucose. The structure of 7N2A one of the major sugar chains, was proposed as; [structure: see text] A structural comparison between PAS-6 and -7 indicated that although they shared the same protein core, their sugar moiety was markedly different, involving the existence of a different pathway during the post-transcriptional modification.

• Journal of the korean society of oceanography
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• 제34권4호
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• pp.214-219
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• 1999

Cells of the dinoflagellate Gyrodinium impudicum form characteristic chains, which are associated with sugar accumulated on the cell surface. To resolve the relationship between chain-formation and cell surface sugar accumulation, confocal microscopy was used to observe sugar accumulation points in the vegetative cells and long chain-forming cells of G. impudicum cells treated with fluorescent-tagged ConA. In the stationary and exponential phases, both vegetative cells and chain-forming cells were similar to each other in fluorescent intensity. There was no evidence that chain-forming cells had a specific location for sugar accumulation on the cell surface. Most of the cells formed 2-cell chains one day after inoculation, but longer chains consisting of 4-8 cells increased markedly in 4day and 8 day cultures. Gyrodinium impudicum chains usually consist of more than four cells, and chains of 8 or even 16 cells can be observed in mature cultures. Temperature played an importantrole in chain-formation of the cells, threshold temperature for the development of long chain-formation was 19 $^{\circ}$C.

• 한국축산식품학회지
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• 제21권4호
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• pp.367-373
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• 2001

MFGM 당단백질의 하나인 PAS-7을 GPC 및 affinity chromatography에 의해 정제하여 2-AB로 형광 표식한 후, anion-exchange column 및 reversed-phase column을 이용해 5개의 성분을 분리하였다. 그 중 가장 상대량이 많은 성분 e에 대하여 RAAM2000을 이용한 당쇄구조 해석을 실시하여, 성분 e는 RAAM2000 GPC에 의하여 4개의 성분으로 분리되어 각각 calibration standard 12.10, 8.88, 5.84 및 4.86GU의 용출위치에 검출되었다. 이 용출위치와 당쇄구조는 livrary의 component-7457과 일치하며, 12.2GU의 크기로 분자량은 1788로 판단되며 library의 당쇄와 약 85%의 확률로 일치했다. 그 결과 성분 e의 당쇄구조는 환원말단에 $\alpha$1-6결합된 fucose를 1개 함유하며, core부분의 비환원말단에 N-acetyllactosamine branch를 2개 함유한 전형적인 biantennary 당쇄구조인 것으로 추축되어, 이전 HPLC, acetolysis, sequential exoglycosidase 소화, NMR분석에 의해 보고된 성분 7N1A의 구조와 일치함으로써, OGS RAAM2000을 이용한 PAS-7의 당쇄구조 해석의 유용성이 증명되었다.

• BMB Reports
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• 제39권5호
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• pp.560-570
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• 2006

Mistletoe (Viscum album) lectins, which are classified as a type II ribosome-inactivating protein (RIP) due to their unique biological function and the potential medical and therapeutic application in cancer cells, receive a rising attention. The heterodimeric glycoproteins contain the A-chain with catalytic activity and the B-chain with sugar binding properties. In recent years, studies involving the lectins from the white berry European mistletoe (Viscum album) and the yellow berry Korean mistletoe (Viscum album coloratum) have been described. However, the detailed mechanism in exerting unique cytotoxic effect on cancer cells still remains unclear. Here, we aim to understand and define the molecular basis and biological effects of the type II RIPs, through the studies of the recombinant Korean mistletoe lectin. To this end, we expressed, purified the recombinant Korean mistletoe lectin (rKML), and investigated its molecular characteristics in vitro, its cytotoxicity and ability to induce apoptotic cell death in cancer cells. To gain structural basis for its catalytic activity and sugar binding properties, we performed homology modeling studies based on the high degree of sequence identity and conserved secondary structure prediction between Korean and European, Himalayan mistletoe lectins, and Ricin.

• 한국환경과학회지
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• 제31권3호
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• pp.227-235
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• 2022

In this study, a biodegradation model of based on molecular cellulose was established. It is a mathematical, kinetic model, assuming that two major enzymes randomly break glycosidic bonds of cellulose molecules, and calculates the number of molecules by applying the corresponding probability and degradation reaction coefficients. Model calculations considered enzyme dose, cellulose chain length, and reaction rate constant ratio. Degradation increased almost by two folds with increase of temperature (5℃→25℃). The change of degradation was not significant over the higher temperatures. As temperature increased, the degradation rate of the molecules increased along with higher production of shorter chain molecules. As the reaction rates of the two enzymes were comparative the degree of degradation for any combinations of enzyme application was not affected much. Enzyme dose was also tested through experiment. While enzyme dose ranged from 1 mg/L to 10 mg/L, the gap between real data and model calculations was trivial. However, at higher dose of those enzymes (>15 mg/L), the experimental result showed the lower concentrations of reductive sugar than the corresponding model calculation did. We determined that the optimal enzyme dose for maximum generation of reductive sugar was 10 mg/L.

• 농업과학연구
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• 제36권1호
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• pp.41-50
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• 2009

Fucoidan is a uniquely-structured sulfated fucose-rich polysaccharide derived from brown algae. Recently, the abalone glycosidase-digested fucoidan extract (fucoidan extract) derived from seaweed Cladosiphon novae-caledoniae Kylin (Mozuku) draws much attention because of its clinical anti-cancer effect in Japan. Here, we report the cancer cells-specific apoptosis inducing effects of the fucoidan extract. The fucoidan extract suppressed the growth of various anchorage-dependent and -independent cancer cells. The fucoidan extract contained low molecular weight components, which induced apoptosis of human leukemic HL 60 cells but not of human lymphocytes. It was shown that the fucoidan extract lead caspase 3/7 activation and loss of mitochondrial membrane potential in HL 60 cells. Another function of the fucoidan extract was also observed. It has been known that sugar chain expression on the surface of cancer cell membrane changes dependent on their malignancy. The analysis on sugar chain expression profiling using FITC-labeled lectins revealed that the expression of concanavalin A (Con A) binding sugar chain was enhanced by the treatment of human lung adenocarcinoma A549, human uterine carcinoma HeLa and human fibrosarcoma HT1080 cells with the fucoidan extract. Con A-induced apoptosis of cancer cells was stimulated in a dose-and time-dependent manner by the treatment with the fucoidan extract but not of human normal fibroblast TIG-1 cells.

• 생명과학회지
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• 제17권8호통권88호
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• pp.1157-1165
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• 2007

포도 ASR (VvMSA) 단백질은 hexose transporter 유전자 VvHT1의 전사를 조절하는 조절 인자 중의 하나로서 sugar 및 abscisic acid (ABA) 신호에 의해 발현이 유도된다. 본 연구진은 ACP RT-PCR (annealing control primer reverse transcriptase-polymerase chain reaction) 방법을 이용하여 포도 과실발달 과정에서 조절되는 유전자 중 VvMSA와 동일한 cDNA (VlASR)를 클로닝하였다. 이 유전자는 착과 시기에 발현되기 시작하여 과실이 발달하면서 점점 증가하여 착과 후 10 주에 가장 많이 발현되며, 숙기 후반에는 도리어 발현양이 감소하였다. 포도 asr 유전자의 조절기작을 밝히기 위해, 이 유전자의 genomic clone을 분리하였다. 총 1375 bp로 이루어진 이 유전자 절편에는 open reading frame과 100 bp의 intron을 포함하고 있다. 약 600 bp 길이의 프로모터 내에는 sugar 신호전달과 연관이 있는 것으로 알려진 sugar box(sucrose box 3 +sucrose response box 1)가 있다. 프로모터 절편을 reporter 유전자와 연결하여 Arabidopsis에 도입하고 형질전환체를 분석한 결과, reporter 유전자는 sucrose 처리와 상관없이 항상 발현되었다. 이러한 결과는 포도에서 보고된 ASR/VvHT1를 매개로 하는 sugar/ABA 신호전달계가 asr 유전자가 없는 Arabidopsis에서는 작동되지 않음을 시사하고 있다.

• 한국식품과학회지
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• 제22권6호
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• pp.640-645
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• 1990

우육에 7.5%의 당을 첨가하고 $121^{\circ}C$에서 가열처리하여 근원섬유단백질의 전기영동 pattern 변화를 알아보았다. 당을 첨가하지 않은 경우 가열처리시간이 길어짐에 따라 myosin heavy chain(MHC) 등의 분자량이 큰 단백질의 band강도는 크게 약화되었지만 actin 등의 분자량이 작은 단백질은 거의 변화가 없었으며 당을 첨가한 처리구에서는 가열처리에 의하여 MHC 등의 band강도가 더욱 약화되었는데 특히 glucose 첨가시 15분간 가열처리구에서는 actin band의 강도도 크게 약해졌다. 시료에 peptidase를 작용시킨 후 추출한 단백질의 전기영동 pattern은 거의 변화가 없었으며 chymotrypsin을 작용시켰을 때 근원섬유를 구성하는 단백질들이 소화된 것을 보여주었으나 갈변반응이 심하게 발생하였던 glucose 첨가구에서는 myosin분자 등의 중합체가 나타났다 Trypsin을 작용시켰을 때 전체적으로 chymotrypsin의 경우보다 더욱 소화된 것을 보여주면서 glucose 첨가구에서는 myosin분자 등의 중합체가 더욱 강하게 나타났으며 peptidase chymotrypsin, trypsin을 동시에 작용시켜도 glucose 첨가구에서는 myosin 분자 등의 중합체가 소화되지 못하며 그 강도도 fructose 첨가구의 것보다 강한 것을 보여 주었다.

• Genes and Genomics
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• 제40권11호
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• pp.1157-1167
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• 2018

Sulfolobus species can grow on a variety of organic compounds as carbon and energy sources. These species degrade glucose to pyruvate by the modified branched Entner-Doudoroff pathway. We attempted to determine the differentially expressed genes (DEGs) under sugar-limited and sugar-rich conditions. RNA sequencing (RNA-seq) was used to quantify the expression of the genes and identify those DEGs between the S. acidocaldarius cells grown under sugar-rich (YT with glucose) and sugar-limited (YT only) conditions. The functions and pathways of the DEGs were examined using gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. Quantitative real-time PCR (qRT-PCR) was performed to validate the DEGs. Transcriptome analysis of the DSM 639 strain grown on sugar-limited and sugar-rich media revealed that 853 genes were differentially expressed, among which 481 were upregulated and 372 were downregulated under the glucose-supplemented condition. In particular, 70 genes showed significant changes in expression levels of ${\geq}$ twofold. GO and KEGG enrichment analyses revealed that the genes encoding components of central carbon metabolism, the respiratory chain, and protein and amino acid biosynthetic machinery were upregulated under the glucose condition. RNA-seq and qRT-PCR analyses indicated that the sulfur assimilation genes (Saci_2197-2204) including phosphoadenosine phosphosulfate reductase and sulfite reductase were significantly upregulated in the presence of glucose. The present study revealed metabolic networks in S. acidocaldarius that are induced in a glucose-dependent manner, improving our understanding of biomass production under sugar-rich conditions.

• The Plant Pathology Journal
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• 제35권6호
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• pp.692-697
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• 2019

Agrobacterium rhizogenes-mediated transformation of sugar beet hairy roots expressing single-chain variable fragment (scFv) was exploited to evaluate the efficacy of four antibody-based constructs for interfering with the Beet necrotic yellow vein virus infection. The scFv specific to a major coat protein of virus, p21, was targeted to various cellular compartments including the cytosol (pIC and pICC constructs), apoplast (pIA), and mitochondrion (pIM). After mechanical virus inoculation, most of the hairy root clones expressing scFv in the cytosol displayed low virus titers while the majority of transgenic hairy root clones accumulated antibody in outer membrane of mitochondria or apoplast were infected. This hairy root system provided an efficient and rapid approach to initially investigating root disease resistance like rhizomania prior to transform whole recalcitrant plants such as sugar beet.