• Development and Reproduction
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• v.11 no.3
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• pp.253-261
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• 2007

Lactadherin is a glycoprotein of human milk fat globule membrane that binds to mucin and butyrophilin forming the protein complex. Especially, mucin and lactadherin in human milk efficiently protect infants with poor immune functions right after birth from infections by microorganisms and play important roles for their early survival, growth and development. Lactadherin inhibits the propagation and growth of rotavirus that is a global pathogen causing infants' diarrhea. Recently this protein was known to promote neovascularization and its deficiency related to develop Alzheimer's disease. In this study, the basic biochemical and physiological aspects of lactadherin were investigated. Messenger RNAs were isolated from mammary tissues from Korean women patients to clone a 1.2 kb cDNA and sequenced its DNA to determine its amino acid sequences. The cDNA was cloned to express its 43 kD protein in E. coli, which was confirmed by Western blot. The recombinant protein was purified and injected to 2 rabbits to raise antibodies against it. The semi-purified milk fat globule membrane proteins from Korean women was analyzed by Western blot using the rabbit antibody to give 70, 55, 46, 30 kD bands. Also several polymorphism and SNPs of lactadherin gene from Korean women were observed compared with those of Caucasian women.

• Journal of Photoscience
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• v.8 no.2
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• pp.43-53
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• 2001

a, a parameter that describes how effectively photoinactivated PS II units protect their functional neighbours; car, carotenoids; ΔpH, transthylakoid pH difference; D1 protein, psbA gene product in the PS II reaction centre; f, functional fraction of PS II: F$\_$v//F$\_$m/, the ratio of variable to maximum chlorophyll a fluorescence; k$\_$d/, rate coefficient for degradation of D1 protein; k$\_$i/ and k$\_$r/, rate coefficient for photoinactivation and repair of PS II, respectively; NADP+, oxidized nicontinamide adenine dinucleotide phosphate; P680, the primary electron donor in the PSII reaction centre; Ph, pheophytin; PS, photosystem; Q$\_$A/, first quinone acceptor of an electron in PS II; R$\_$s/, the gross rate of D1 protein synthesis.

• BMB Reports
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• v.34 no.4
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• pp.371-378
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• 2001

The Glycoprotein D (gD) gene of the HSV-1 strain F was cloned, sequenced, recombinated into the HcNPV (Hyphantria cunea nuclear polyhedrosis virus) expression vector and expressed in insect cells. The gD gene was located in the 6.43 kb BamHI fragment of the strainF. The open reading frame (ORF) of the gD gene was 1,185 by and codes 394 amino acid residues. Recombinant baculoviruses, GD-HcNPVs, expressing the gD protein were constructed. Spodoptera frugiperda cells, infected with the recombinant virus, synthesized a matured gX-gD fusion protein with an approximate molecular weight of 54 kDa and secreted the gD proteins into the culture media by an immunoprecipitation assay The fusion gD protein was localized on the membrane of the insect cells, seen by using an immunofluorescence assay The deduced amino acid sequence presents additional characteristics compatible with the structure of a viral glycoprotein: signal peptide, putative glycosylation sites and a long C-terminal transmembrane sequence. These results indicate the utility of the HcNPV-insect cell system for producing and characterizing eukaryotic proteins.

• Food Science and Biotechnology
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• v.18 no.3
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• pp.610-617
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• 2009

The stability of corn oil-in-water emulsions coated by milk proteins, sodium caseinate (CAS), or whey protein concentrate (WPC), was compared under the environmental stress of pH change. Emulsions were prepared at 0.1 of protein:oil because the majority of droplets were relatively small ($d_{32}=0.34$ and $0.35\;{\mu}m$, $d_{43}=0.65$ and $0.37\;{\mu}m$ for CAS- and WPC-emulsions, respectively) and there was no evidence of depletion flocculation. As the pH of the emulsions was gradually dropped from 7 to 3, there was no significant difference in the electrical charges of the emulsion droplets between the 2 types of emulsions. However, laser diffraction measurements, microscopy measurements, and creaming stability test indicated that WPC-emulsions were more stable to droplet aggregation than CAS-emulsions under the same circumstance of pH change. It implies that factors other than electrostatic repulsion should contribute to the different magnitude of response to pH change.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.135-135
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• 1993

신호전달과정에 중요한 역할을 하고 있는 다기능 serinei/threonine 단백질인산화효소인 protein kinase C(PKC)의 연구를 위해 이 효소의 정제를 뇌에서 착수하였다 PKC의 활성측정을 myelin basic protein을 기질로 하여 20 mM Tris 완충용액 PH 7.5, 0.15 mM [${\gamma}$-$^{32}$P]ATP(3 $\times$ $10^{5}$ cpm), 0.1 mM $Ca^{2＋}$, 10$\mu\textrm{g}$ phosphatidylserine과 2$\mu\textrm{g}$ diolein을 넣어 반응시켰다. 반응은 TCA로 정지시킨 후 방사성 단백질을 Millipore filter paper로 걸러 섬광 계수기로 읽었다. Cytosol PKC의 정제과정은 첫 단계에서 DEAE-cellulose를 사용하였으며, phenyl sepharose CL-4B와 protamine agarose를 연속적으로 이용하여 800배의 정제에 성공했다. SDS-PACE 상에서 80 kD로 나타났으며 순도는 95 % 이상이였다. 이를 이용 PKC의 각종 기질 연구에 착수하기 시작했으며, 이중 MBP의 인산화연구를 통한 myelin의 안정성과 MBP와의 구조 관계가 일부 수행되고 있다 연차적으로 PKC와 이와 관련된 단백질의 특성을 살피기 위해 뇌의 PKC 기질 중 cold stress를 통해 환경에 민감한 것을 찾고 있으며, 현재 autoradiography를 이용해 80 kD, 54 kD, 49 kD와 35 kD의 단백질이 연구대상이 되고있다. 그 중 49 kD는 B-50(또는 GAP43, neuromodulin이라고도 함)일 가능성이 높아 이 단백질 조절과 PKC 활성화 사이의 관계 정립이 흥미로운 과제로 대두되고 있다.다.

• BMB Reports
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• v.43 no.1
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• pp.17-22
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• 2010

In this study, a novel member of BTB-kelch proteins, named KBTBD7, was cloned from a human embryonic heart cDNA library. The cDNA of KBTBD7 is 3,008 bp long and encodes a protein product of 684 amino acids (77.2 kD). This protein is highly conserved in evolution across different species. Western blot analysis indicates that a 77 kD protein specific for KBTBD7 is wildly expressed in all embryonic tissues examined. In COS-7 cells, KBTBD7 proteins are localized to the cytoplasm. KBTBD7 is a transcription activator when fused to GAL4 DNA-binding domain. Deletion analysis indicates that the BTB domain and kelch repeat motif are main regions for transcriptional activation. Overexpression of KBTBD7 in MCF-7 cells activates the transcriptional activities of activator protein-1 (AP-1) and serum response element (SRE), which can be relieved by siRNA. These results suggest that KBTBD7 proteins may act as a new transcriptional activator in mitogen-activated protein kinase (MAPK) signaling.

• Journal of Photoscience
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• v.9 no.2
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• pp.55-58
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• 2002

The reaction center Dl protein of photosystem II is the target of photodamage by excess illumination. The Dl protein is damaged by reactive oxygen species generated by photochemical reactions and then degraded by specific proteolytic enzymes. We found that the Dl protein also cross-links with the surrounding polypeptides, such as D2 and CP43 in isolated thylakoids or photosystem II-enriched membranes from spinach under the illumination with strong visible light. The cross-linking was observed in spinach leaf discs as well when they were illuminated at higher temperature (40°C). It was also shown that the cross-linked products are digested efficiently by a protease(s) in the stroma. Thus the cross-linking/digestion processes of the Dl protein seem to comprise a new pathway in the turnover of the photodamaged Dl protein. It should be noted, however, that the cross-linked products of the Dl protein and CP43 induced by endogenous cationic radicals in the donor-side photoinhibition are resistant to proteolytic digestion. Accumulation of these cross-linked products in the thylakoids may lead to the decay of the function of chloroplasts and finally to the death of plant cells. Thus, we suggest that the quality control of photosystem II, especially removal of the cross-linked products of the Dl protein, is crucial for the survival of chloroplasts under the light stress.

• Journal of Plant Biotechnology
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• v.31 no.4
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• pp.319-323
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• 2004

Soluble latex protein fraction excreted from Euporbia lathyris laticifer was resolved by 10% SDS-polyacrylamide gel electrophoresis to identify distinctively displayed latex major protein bands including ELp65, ELp55, ELp43, ELp32 and ELp23. Among them, ELp65 was purified by ammonium sulfate precipitation, gel permeation chromatography and ion exchange chromatography. Its N-terminal amino acid sequencing revealed its homology to the leading region of mature peptide of tomato p69a subtilisin-like protease, suggesting a certain role involved in plant defense system. In the analysis of Southern blot hybridization using PCR-amplified tomato p69a probe DNA, E. lathyris genome was suggested to have a gene family consisting of 3-5 gene members putatively encoding subtilisin-like proteases.

• The Korean Journal of Food And Nutrition
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• v.29 no.5
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• pp.684-691
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• 2016

In this study, we analyzed the biochemical factors in lotus (Nelumbo nucifera) leaf, stem, and yeonjabang and their effects on serum factor levels in mice fed a high-fat (HF) diet. The loutus leaf showed $9.47{\pm}0.30%$ moisture content, $8.25{\pm}0.39%$ ash, $21.45{\pm}1.25%$ crude protein, and $2.21{\pm}0.13%$ crude fat content; the lotus stem showed $11.84{\pm}0.43%$ moisture, $10.21{\pm}0.64%$ ash, $17.55{\pm}0.92%$ crude protein, and $4.16{\pm}0.23%$ crude fat content; and the lotus yeonjabang showed $11.86{\pm}0.50%$ moisture, $6.81{\pm}0.51%$ ash, $18.71{\pm}1.02%$ crude protein, and $3.95{\pm}0.15%$ crude fat. Blood triglyceride levels were higher in the HF group ($146.43{\pm}38.81mg/dL$), and lower in the HF+yeonjabang groups ($98.00{\pm}17.18mg/dL$). In particular, blood triglyceride levels were significantly lower in the groups that had 10% dry yeonjabang powder added to the high-fat diet. The inclusion of excessive high-fat diet increased concentrations of serum insulin and leptin. Serum leptin concentrations were highest in the HF group mice ($3.00{\pm}1.35ng/dL$), whereas they were significantly lower in the HF+yeonjabang groups by $1.34{\pm}0.52ng/dL$ (p<0.05). Thus, addition of dry yeonjabang powder to the high-fat diet was more effective in regulating the levels of serum triglycerides and leptin in mice. Additional studies would help in the development of yeonjabang as a functional food.

• Journal of Microbiology and Biotechnology
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• v.12 no.5
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• pp.773-779
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• 2002

A gene (hap) encoding aminopeptidase from the chromosomal DNA of Bacillus licheniformis was cloned. The gene is 1,347 bp long and encodes a 449 amino acid preproprotein with a major mature region of 401 amino acids (calculated molecular mass 43,241 Da). N-Terminal sequence of the purified protein revealed a potential presence of N-terminal propeptide. The deduced primary amino acid sequence and the mass analysis of the purified protein suggested that a C-terminal peptide YSSVAQ was also cleaved off by a possible endogeneous protease. Tho amino acid sequence displayed 58% identity with that of the aminopeptidase from alkaliphilic Bacillus halodurans. This bacterial enzyme was overexpressed in recombinant Escherichia coli and Bacillus subtilis cells. Clones containing the intact hap gene, including its own promoter and signal sequence, gave rise to the synthesis of extracellular and thrmostable enzyme by B. subtilis transformants. The secreted protein exhibited the same biochemical properties and the similar apparent molecular mass as the B. lichenzyormis original enzyme.