• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.2
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• pp.59-63
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• 2003

The protein disulfide isomerase (PDI) reaction kinetics has been studied to evaluate its effect on the monoclonal antibody (Mab) refolding and assembly which accompanies disulfide bend formation. The MAb in vitro assembly experiments showed that the assembly rate of heavy and light chains can be greatly enhanced in the presence of PDI as compared to the rate of assembly obtained by the air-oxidation. The reassembly patterns of MAb in-termediates were identical for both with and without PDI, suggesting that the PDI does not determine the MAb assembly pathway, but rather facilitates the rate of MAb assembly by promoting PDI catalyzed disulfide bond formation. The effect of growth rate on PDI activities for MAb production has also been examined by using continuous culture system. The specific MAb productivity of hybridoma cells decreased as the growth rate increased. However, PDI activities were nearly constant fur a wide range of growth rates except very high growth rate, indicating that no direct correlation between PDI activity and specific MAb productivity exists.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.5
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• pp.1273-1278
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• 2007

In living system, various types of metal chelated protein show their intrinsic biological activities. In order to investigate the chelation reaction between protein and metal, zinc chelated peptide was systhesized by the peptide, hydrolyzed protein, with zinc. And simple analytical method fot the chelation reaction was developed using MALDI-TOF mass spectrometry.

• Journal of Life Science
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• v.7 no.4
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• pp.322-328
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• 1997

Two phosphorylated proteins having molecular weights of 57kD and 72kD were detected from the slubilized membrane protein fraction of mating type a cells of Rhodosporidium toruloides which belongs to heterobasidiomycetous yeast. The phosphorylation of the protein was inhibited by a sexual pheromone, Rhodotorucine A (Rh. A), which is secreted from mating type a cells. On the other hand, counterpart mating type A cells and M-39 strain which is a styerile mutant derived from a cells, had also the same two phosphorylated proteins, However, the phosphorylation of the protein from A cells, and M-39 strain were not inhibited by the Rh. A. It suggests that inhibition of the phosphorylation reaction by the Rh. A in mating type a cells is a mating-type-specific reaction that relate to transduction mechanism of sexual pheromone signaling.

• Journal of Photoscience
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• v.9 no.2
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• pp.1-4
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• 2002

Hula-twist is a volume-conserving photoisomerization reaction mechanism postulated in 1985 to account for the rapid photoisomerization of the retinyl chromophore in rhodopsin. The requisite stereochemical consequence of simultaneous isomerization of a double bond and an adjacent single bond has recently been demonstrated in isomerization of pre-vitamin D in an organic glass and by many other examples of organic systems already reported in the literature This paper reports the consequence in applying the mechanism to the primary photochemical process of several photosensitive biopigments: bilirubin, photoactive yellow protein, bacteriorhodopsin and rhodopsin. It is shown that the anchored nature of the chromophores must first be taken into consideration.

• Journal of Ginseng Research
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• v.16 no.2
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• pp.129-137
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• 1992

This study was carried out to investigate the localization of lipids and lipase activity with lipid staining and cytochemical technique in endosperm cells of Panax ginseng C.A. Meyer seed. In endosperm cells of indehiscent seed, protein bodies facing the umbiliform layer are different in electron density during the various degraded processes. Gradually, protein matrix near the cell wall was lysed and electron lucent inclusions appeared on umbiliform layer. The protein body with high electron density and the spherosome with low electron density were observed in endosperm cells. As a result of lipid staining, electron density of spherosome is more intense than those of the protein matrix within the protein body in endosperm cells of indehiscent seed. Free spherical spherosomes within the umbiliform layer have a high electron density. The spherical spherosomes were more electron densed and were uniform in comparison with the cytoplasmic proteinaceous granules in endosperm cells of seed with red seed coat. The major component of spherosome was determined to be lipid. Lipase activity occurs in the spherosome and near the endosperm cell wall facing the umbiliform layer. Cytochemical reaction products of lipase were observed in the spherosome membrane and in the inner regions of spherosome. After protein bodies were digested, lipase activities were observed in free spherosomes and near the cell wall of endosperm cells. Umbiliform layer composing of fibrillized wall and digested materials of the endosperm cell showed a little lipase reaction products.

• Korean Journal of Agricultural Science
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• v.24 no.2
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• pp.121-125
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• 1997

A total of 437 landraces of rice from Vietnam were analyzed for total seed protein by SDS-PAGE and phenol reaction. The different types of glutelin $\alpha$ subunits were detected. The level of wx protein with 60kDa molecular weight was divided into 3 groups, corresponding to non-glutinous, intermediate and glutinous starch types. Based on the variation in seed storage protein and wx protein, landraces were classified into 7 groups. Frequency distribution of types A and B of glutelin $\alpha$ subunits changed with the latitude at which rice landraces were collected. Geographical cline for phenol reaction was detected.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.769-773
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• 2001

Protein content of okara and soybean were found to be 37.3% and 42.5%, respectively by micro-Kjeldahl analysis. Solubility of okara protein in phosphate buffer (pH 8) was 10% versus soy protein of 68.4%. Insolubilization of okara protein was mostly due to disulfide bonding between cysteine residues caused by excessive heat treatment during soymilk processing: hydrophobic interactions and hydrogen bondings were involved to lesser extent. Optimum extraction temperature and time were $60^{\circ}C$ and 40 min. Typical solubility profile of soy protein disappeared for okara protein though minimum solubility of the protein was around pH 3.0. Treating okara with protease was effective in solubilizing okara protein and solubility increased to 19.2%. Optimum reaction temperature and time were $80^{\circ}C$ and 50 min, respectively. Cell wall degrading enzyme did not increase solubility of the protein, however. Through enzymatic reaction okara protein could be effectively solubilized for uses as food ingredient.

• Journal of Ginseng Research
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• v.13 no.2
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• pp.158-164
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• 1989

In order to determine the relationships between the lea(-burning disease and the light harvesting chlorophyll-protein (LHCP) complex in Panax ginseng C. A. Meyer, we investigated the chlorophyll-protein (CP) complex of the thylakoid membrane and its characteristics. In P. ginseng four Cp-complex bands determined by non-denaturing SDS-PAGE were identified CP I'(containing reaction center of photosystem I and LHCP I antennae), CP I (reaction center of photosystem I) LHCP II** (oligoform of LHCP II), and LHCP II (photosystem II antennae, CP 26 and CP 29) by Bassis and Dunahay's procedures. Under our experimental condition, the CP I band was only observed in P. ginseng and the band intensity of LHCP II** in P ginseng was higher than in spinach and soybean. There were differences in the absorption and fluorescence spectra and chlorophyll a/b ratio of the CP-complex bands between P. ginseng and other Plants. The Polypeptidr content of P. ginseng thylakoid was lower than in spinach and soybean thylakoid, and the Polypeptide profiles of P. ginseng was low band intensity, especially about 29-35 kD, 55 kD, and 60 kD, compared to spinach and soybean. The inhibitory effects of 2,5-dimethylfuran, specific singlet oxygen ($^1O_2$) quencher, showed that singlet oxygen destroyed 60% of chl.a, 90% of chl.b and 70% of carotenoid in bleaching P. ginseng with leaf-burning disease.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.2
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• pp.181-189
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• 2008

The aim of this study was to evaluate the effects of $Ca^{2+}$, $HCO_3{^-}$ and BSA on the in vitro capacitation-associated protein tyrosine phosphorylation, hyperactivation and acrosome reaction in guinea pig sperm. Caudal epididymal sperm were incubated in four different groups: modified TALP (Tyrode's albumin lactate pyruvate) or TALP without one of the medium constituents ($Ca^{2+}$, $HCO_3{^-}$ and BSA). After incubation for the required time (0 h, 0.5 h, 1 h, 3 h, 5 h, and 7 h), sperm were removed for further experiment. The capacitation effect was assessed by CTC (Chlortetracycline) staining. Western blotting and indirect immunofluorescence were used to analyze the level and localization of tyrosine phosphorylation. The results showed that guinea pig sperm underwent a time-dependent increase in protein tyrosine phosphorylation during the in vitro capacitation and the percentage of protein tyrosine phosphorylated sperm increased from 36% to 92% from the beginning of incubation to 7 h incubation. Also, there was a shift in the site of phosphotyrosine-specific fluorescence from the head of sperm to both the head and the flagellum. Moreover, an absence of $Ca^{2+}$ or $HCO_3{^-}$ inhibited in vitro hyperactivation and acrosome reaction and decreased the phosphorylation of the proteins throughout the period of in vitro capacitation. However, an absence of BSA could not influence these processes if substituted by polyvinyl alcohol (PVA) in the medium.

• Journal of Chest Surgery
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• v.51 no.3
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• pp.187-194
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• 2018

Background: Death domain-associated protein (DAXX), originally identified as a pro-apoptotic protein, is now understood to be either a pro-apoptotic or an anti-apoptotic factor with a chromatin remodeler, depending on the cell type and context. This study evaluated DAXX expression and its clinical implications in squamous cell carcinoma of the esophagus. Methods: Paraffin-embedded tissues from 60 cases of esophageal squamous carcinoma were analyzed immunohistochemically. An immune reaction with more than 10% of tumor cells was interpreted as positive. Positive reactions were sorted into 2 groups: reactions in 11%-50% of tumor cells and reactions in more than 51% of tumor cells, and the correlations between expression and survival and clinical prognosticators were analyzed. Results: Forty-three of the 60 cases (71.7%) showed strong nuclear DAXX expression, among which 19 cases showed a positive reaction (31.7%) in 11%-50% of tumor cells, and 24 cases (40.0%) showed a positive reaction in more than 51% of tumor cells. A negative reaction was found in 17 cases (28.3%). These patterns of immunostaining were significantly associated with the N stage (p=0.005) and American Joint Committee on Cancer stage (p=0.001), but overall survival showed no significant difference. There were no correlations of DAXX expression with age, gender, or T stage. However, in stage IIB (p=0.046) and stage IV (p=0.014) disease, DAXX expression was significantly correlated with survival. Conclusion: This investigation found upregulation of DAXX in esophageal cancer, with a 71.7% expression rate. DAXX immunostaining could be used in clinical practice to predict aggressive tumors with lymph node metastasis in advanced-stage disease, especially in stages IIB and IV.