• BMB Reports
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• v.38 no.5
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• pp.591-594
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• 2005

One of the small proteins from Helicobacter pylori, HP1242, was investigated by the solution nuclear magnetic resonance (NMR) spectroscopy. HP1242 is known as a 76-residue conserved hypothetical protein and its function cannot be identified based on sequence homology. Here, the results of the backbone $^1H$, $^{15}N$, and $^{13}C$ resonance assignments of the HP1242 are reported using double- and triple-resonance techniques. About 95% of all of the $^1HN$, $^{15}N$, $^{13}CO$, $^{13}C{\alpha}$, and $^{13}C{\beta}$ resonances that cover 75 non- Proline residues of the 76 residues are clarified through sequential- and specific- assignments. In addition, three helical regions were clearly identified on the basis of the resonance assignments.

• Archives of Pharmacal Research
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• v.21 no.3
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• pp.315-319
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• 1998

Gastric smooth muscle of cats was used to investigate the involvement of protein kinase in vanadate-induced contraction. Vanadate caused a contraction of cat gastric smooth muscle in a dose-dependent manner. Vanadate-induced contraction was totally inhibited by 2 mM EGTA and 1.5 mM $LACI_3$ and significantly inhibited by $10\mu$M verapamil and $1\mu$M nifedipine, suggesting that vanadate-induced contraction is dependent on the extracellular $Ca^{2+}$ concentration, and the influx of extracellular $Ca^{2+}$ was mediated through voltage-dependent $Ca^{2+}$ channel. Both protein kinase C inhibitor and tyrosine kinase inhibitor significantly inhibited the vanadate-induced contraction and the combined inhibitory effect of two protein kinase inhibitors was greater than that of each one. But calmodulin antagonists did not have any influence on the vanadate-induced contraction. On the other hand, both forskolin ($1\mu$M) and sodium nitroprusside ($1\mu$M) significantly inhibited vanadate-induced contraction. Therefore, these results suggest that both protein kinase C and tyrosino kinase are involved in the vanadate-induced contraction which required the influx of extracellular $Ca^{2+}$ in cat gastric smooth muscle, and that the contractile mechanism of vanadate may be different from that of agonist binding to its specific receptor.

• Parasites, Hosts and Diseases
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• v.41 no.2
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• pp.89-96
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• 2003

Among the panel of monoclonal antibodies (mAb) against Toxoplasma gondii, mAb of Tg621 (Tg621) clone blotted 38 kDa protein which localized in the cytoplasm of tachyzoites by immunofluorescence microscopy The protein was not released into the parasitophorous vacuole during or after invasion. The cDNA fragment encoding the protein was obtained by screening a T. gondii cDNA expression library with Tg621. The full length cDNA sequence was completed with 5’-RACE as 1,592 bp, which contained open reading frame of 942 bp. The deduced amino acid sequence of Tg621 consisted of a polypeptide of 313 amino acids, with significant homology to ribosomal P proteins (RPP) of other organisms especially high to those of apicomplexan species. The expressed and purified TgRPP was assayed in western blot with the sera of toxoplasmosis patients and normal sera, which resulted in the 74.0% of positive reactions in toxoplasmosis patients whereas 8.3% in normal group. Therefore, the antibody formation against TgRPP in toxoplasmosis patients was regarded as specific for T. gondii infection and suggested a potential autoantibody.

• The Korean Journal of Zoology
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• v.35 no.2
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• pp.203-210
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• 1992

Hsp70, a 70 kDa protein, is the maior protein expressed when cells are heat-shocked. A cDNA library from mouse ID13 cells was screened with the human hsp70 gene as a probe, and a positive clone was obtained. The positive clone was subcloned into puc19 and the precise restriction was obtained. The CDNA was sequenced by the Sanger's dideoxv termination method. Single open reading frame that codes for a protein of 70 kDa was found. The DNA sequence of the cloned mouse DNA shows great homology (66-90%) with other mouse hsp70 genes and somewhat less homology (50",) with E. coli hsp70 gene (dnak). With the exception of one amino acid, the protein sequence deduced from the CDNA is identical to the mouse that shock cognate protein 70 (hsc70) that is constitutivelv expressed at normal temperature. The result suggests that the cloned CDNA encodes a hsc70 family rather than a heatinducible family.mily.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.493-501
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• 1986

The present work aims to estimate the effect of heat treatment on the in vitro protein digestibility and formation of trypsin inhibitor or trypsin indigestible substrate(TIS) of raw and defatted flounder. It was also carried out to assess the formation of lipid-protein complexes under the conditions of different ratio of lipid addition. The in vitro protein digestibility increased when steamed for 5 min showing $88.09\%$ in raw and $90.56\%$ in defatted samples, respectively. After 40 min steaming, the digestibility decreased by $2{\sim}4\%$. As for microwaving, heating for 1 min resulted in slight increase of digestibility, however, heating for 7 min did decrease of digestibility by $3{\sim}4\%$ for both raw and defatted materials. There was no difference in fatty acid composition found with heat treatment. The major fatty acids of flounder meat were $C_{16:0},\;C_{16:1},\;C_{18:1},\;C_{20:5},\;C_{22:6}$ and the ratio of the unsaturated to saturated was 67.3:32.6. Fat oxidation and nonenzymatic browning were enhanced by heat treatment and protein solubility decreased necessarily as the brown pigment formation increased. On the other hand, the effects on the digestibility and TIS of the complexes formed from interaction of lipid and myofibrillar or meat protein of flounder were examined. The interaction of protein with lipid was considered to mostly contribute to the drop of digestibility of fish products. The digestibility of myofibrillar protein was $93.72\%$ for flounder, and it generally decreased as the amount of lipid added to protein and reaction time increased. Also mixed and heated samples were more active in digestibility decline than those mixed after heating. The result probably indicated that lipid-protein interaction was involved in the drop of digestibility which coincided with protein denaturation.

• Journal of Life Science
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• v.29 no.9
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• pp.949-954
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• 2019

Membrane topology is a key characteristic of membrane proteins. We previously reported the cloning of the chromosome 4 open-reading frame 32 (C4orf32) gene as a potential membrane protein; however, the cellular localization and membrane topology of C4orf32 was as yet unknown. In this study, we found that green fluorescent protein (GFP) fused to the C-terminus of C4orf32 (C4orf32-GFP) was localized to the endoplasmic reticulum (ER). We applied three tools to identify determinants of C4orf32 topology: protease protection, fluorescence protease protection (FPP), and an inducible system using the ternary complex between FK506 binding protein 12 (FKBP), rapamycin, and the rapamycin-binding domain of mTOR (FRB) (the FRB-rapamycin-FKBP system). Using protease protection and FPP assays, we found that the GFP tag in C4orf32-GFP was localized to the cytoplasmic surface of the ER membrane of HeLa cells. Protease protection and FPP assays are useful and complimentary tools for identifying the topology of GFP fusion membrane proteins. The FRB-rapamycin-FKBP system was also used to study the topology of C4orf32. In the absence of rapamycin, a monomeric red fluorescent protein-FKBP fusion (mRFP-FKBP) and C4orf32-GFP-FRB were localized to the cytoplasm and the ER membrane, respectively. However, in the presence of rapamycin, the mRFP-FKBP was shifted from the cytoplasm to the ER and colocalized with the C4orf32-GFP-FRB. These results indicate that the FRB moiety is facing the cytoplasmic surface of ER membrane. Overall, our results clearly suggest that C4orf32 belongs to the family of type I ER resident membrane proteins.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.1
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• pp.13-22
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• 1985

A study was undertaken to evaluate the nutritional quallity of protein from precooked seafoods. Procedures for evaluation included protein efficiency ratio(PER) using the rat, computed PER(C-PER) and discriminant computed PER(DC-PER) techniques. These procedures involve the determination of in vitro digestibility and amino acid composition of the sample prior to computation of C-PER and CD-PER value in laver was higher. For the oyster, the C-PER value was very close to the PER value obtained from the rat assay. The difference between DC-PER value and rat-PER or NPR was slightly lower than that between C-PER and rat-PER except oyster and laver. Seafood samples which posses a high in vitro protein digestibility may need the DC-PER procedure could offer more advantages in predicting the protein quality of seafood samples than the DC-PER procedure which showed poor in vitro digestibility.

• Korean Journal of Clinical Laboratory Science
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• v.36 no.2
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• pp.185-192
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• 2004

Overexpressions of the estrogen receptors(ER), progesterone receptors(PR) and C-erbB-2 protein are important determiners of the response to chemotherapy in the breast cancer. For detecting ER, PR and C-erbB-2, immunohistochemistry are currently regarded as standard method. The purposes of this study compared to histologic grade and expression of the ER, PR and C-erbB-2 in breast cancer. We examined overexpression of ER, PR and C-erbB-2 protein in 84 breast carcinomas by using immunohistochemical stains. The following results were obtained. For histologic grade, 10 cases(11.9%) showed carcinoma in situ, 16 cases(19%) showed grade I, 36 cases (42.9%) showed grade II, and 22 cases(26.2%) showed grade III among the 84 test samples. The average positive rate ER and PR was 63%, 46% showed carcinoma in situ, 80%, 60% showed grade I, 64%, 41% showed grade II, 34%, 23% showed grade III, respectively. The induction of PR increased when induction of ER increased, thus showing significant relationship(p<0.05). The expression of C-erbB-2 protein was 9 cases(10.7%) in one positive(1+), 9 cases(10.7%) in two positive(2+), and 9 cases(10.7%) in three positive(3+). C-erbB-2 protein expression showed no statistical significance. In conclusion, ER and PR positive rates were inversely associated with histologic grades significantly(p<0.05). C-erbB-2 showed no significant difference with histologic grade. However ER, PR and C-erbB-2 showed significant relationship with each other(p<0.05). Therefore, these findings might be an important prognostic factor and might be arranged as a regular pathological examination in cases of breast cancer.

• Journal of Ginseng Research
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• v.18 no.2
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• pp.108-112
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• 1994

Rats (Sprague Dawley, male, 200 g) were fed with 15% corn oil containing a large quantity of 18 2 (linoleic acid) for 3 weeks, and were followed by feeding the petroleum ether extracts from Korean red ginseng for 3 weeks. cGMP was produced more in platelets prepared from both 15% corn oil and petroleum ether extracts-fed group than in platelets only 15% corn oil-fed group, indicating that the production of cGMP is increased by feeding the petroleum ether extracts. When this platelet was stimulated by phorbol-12-myristate-13-acetate (PMA), the level of cGMP was decreased. However, the platelets in medium containing protein fraction (200 $\mu\textrm{g}$/ml) was stimulated by PMA, the production of cGMP inhibited by PMA was increased by 3 times or more. These results suggest that both the protein fraction and the petroleum ether extracts from Korean red ginseng are synergistic in the productiorl of cGMP, and they may have the antiplatelet effects.

• Applied Biological Chemistry
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• v.36 no.3
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• pp.172-177
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• 1993

To extract insoluble proteins from sesame meal residue by microorganism, the sesame meal residue was treated with crude enzyme solution of Bacillus sp. CW-1121. The foaming capacity of salt soluble protein was quite lower than that of water soluble protein and the foaming stability of salt soluble protein decreased abruptly in 10 min., while it sustained for 30 min in case of water soluble protein. Emulsion capacities of all the protein fractions showed minimum value near isoelectric point of protein and salt soluble protein had lower emulsion capacities than that of water soluble protein. The emulsion stability of the protein was relatively stable for 30 min at $80^{\circ}C$. Oil and water absorption capacities of salt soluble protein were higher than those of water soluble protein.