• Parasites, Hosts and Diseases
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• v.36 no.4
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• pp.261-268
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• 1998

The present study was undertaken to investigate the role of cysteine proteinase of Trichomonas vaginalis in escaping from host defense mechanism. A cysteine proteinase of T. vaginalis was purified by affinity chromatography and gel filtration. Optimum pH for the purified proteinase activity was 6.0. The proteinase was inhibited by cysteine and serine proteinase inhibitors such as E-64, NEM, IAA, leupeptin. TPCK and TLCK, and also by $Hg^{2+}$, but not affected by serine-, metallo-, and aspartic proteinase inhibitors such as PMSF, EDTA and pepstatin A. However, it was activated by the cysteine proteinase activator, DTT. The molecular weight of a purified proteinase was 62 kDa on gel filtration and 60 kDa on SDS-PAGE. Interestingly, the purified proteinase was able to degrade serum IgA, secretory IgA, and serum IgG in time- and dose-dependent manners. In addition, the enzyme also degraded hemoglobin in a dose-dependent manner. These results suggest that the acidic cysteine proteinase of T. vaginalis may play a dual role for parasite survival in conferring escape from host humoral defense by degradation of immunoglobulins, and in supplying nutrients to parasites by degradation of hemoglobin.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.4
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• pp.534-541
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• 2009

The aim of this study was to evaluate the effects of gamma irradiation (${\gamma}$-irradiation) at doses of 15, 30 and 45 kGy on chemical composition, anti-nutritional factors, ruminal dry matter (DM) and crude protein (CP) degradibility, in vitro CP digestibility and to monitor the fate of true proteins of full-fat soybean (SB) in the rumen. Nylon bags of untreated or ${\gamma}$-irradiated SB were suspended in the rumens of three ruminally-fistulated bulls for up to 48 h and resulting data were fitted to a nonlinear degradation model to calculate degradation parameters of DM and CP. Proteins of untreated and treated SB bag residues were fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Digestibility of rumen undegraded CP was estimated using the three-step in vitro procedure. The chemical composition of raw and irradiated soybeans was similar. Results showed that phytic acid in ${\gamma}$-irradiated SB at dose of 30 kGy was eliminated completely. The trypsin inhibitor activity of 15, 30 and 45 kGy ${\gamma}$-irradiated SB was decreased (p<0.01) by 18.4, 55.5 and 63.5%, respectively. From in sacco results, ${\gamma}$-irradiation decreased (p<0.05) the washout fractions of DM and CP at doses of 30 and 45 kGy, but increased (p<0.05) the potentially degradable fractions. Gamma irradiation at doses of 15, 30 and 45 kGy decreased (p<0.05) effective degradability of CP at a rumen outflow rate of 0.05 $h^{-1}$ by 4.4, 14.4 and 26.5%, respectively. On the contrary, digestibility of ruminally undegraded CP of irradiated SB at doses of 30 and 45 kGy was improved (p<0.05) by 12 and 28%, respectively. Electrophoretic analysis of untreated soybean proteins incubated in the rumen revealed that ${\beta}$-conglycinin subunits had disappeared at 2 h of incubation time, whereas the subunits of glycinin were more resistant to degradation until 16 h of incubation. From the SDS-PAGE patterns, acidic subunits of 15, 30 and 45 kGy ${\gamma}$-irradiated SB disappeared after 8, 8 and 16 h of incubation, respectively, while the basic subunits of glycinin were not degraded completely until 24, 48 and 48 h of incubation, respectively. It was concluded that ${\gamma}$-irradiated soybean proteins at doses higher than 15 kGy could be effectively protected from ruminal degradation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.823-828
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• 1998

The objective of this study is to investigate cryoprotective effects of corn starch enzyme hydrolysates of nonsweet and low-calories on denaturation of frozen fish protein. The cryoprotective effects of were examined in Alaska pollack actomyosin solution by changes in SDS-PAGE pattern, solubility, and $Ca^{2+}$-ATPase activity. When samples stored for 0 and 30 days were compared on SDS-PAGE patterns, severe changes in all bands were shown on the control sample regardless of storage temperature, especially in myosin heavy chain (MHC). Not much difference no appeared the electrophoretic pattern in case of the samples containing sucrose at any storage temperature during 30 days of storage. The cryoprotective effect of the hydrolysates were markedly dependant on storage temperature and no MHC band was found in the samples stored at $-5^{\circ}C$. The SDS-PAGE patterns of sample stored at $-20^{\circ}C$, however, completely maintained after 30 days or storage. When the samples were stored at $-5^{\circ}C$, the solubility of the sample containing sucrose was retained at $90\%$ after 30 days of storage, whereas dramatically decreased in other samples. The samples including sucrose, D.E. 10, 15, and 20 revealed $90\%$ in solubility when stored at $-20^{\circ}C$. The tendency of remaining $Ca^{2+}$-ATPase activity was almost shown the same as that of solubility.

• Korean Journal of Weed Science
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• v.16 no.4
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• pp.354-361
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• 1996

This study was conducted to evaluate the susceptibility of rice(Oryza sativa L.) cultivars to herbicide thiobencarb through the determination of protein patterns using SDS-PAGE. In both greenhouse and laboratory screening tests, IR 10198-66-2 and IR 9660-50-3-1 showed relatively tolerant response to thiobencarb, while IR 22, IR 31802-48-2-2-2 and IR 20656-R-R-R-6-1 were susceptible to it. The total protein content of susceptible cultivars markedly decreased as the thiobencarb concentrations increased, but tolerant cultivars such as IR 10198-66-2 and IR 9660-50-3-1 showed very slight changes suggesting that protein synthesis of susceptible cultivars may be inhibited by thiobencarb. The protein profiles of the tolerant cultivars were not much affected by thiobencarb treatment. However, the protein spots with molecular weights of 14.4 kD and 55 kD in the susceptible cultivar of IR 22 disappeared with the treatment of 3 ppm thiobencarb, indicating that differential susceptibilities of rice cultivars against thiobencarb can be attributed to their difference in protein metabolism affected by thiobencarb.

• Journal of Life Science
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• v.18 no.6
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• pp.814-825
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• 2008

Ascochlorin (ASC) is prenyl-phenol compound that was isolated from the fungus Ascochyta viciae. ASC reduces serum cholesterol and triglyceride levels, and suppresses hypertension, tumor development, ameliorates type I and II diabetes. Here, to better understand the mechanisms by which ASC regulates physiological or pathological events and induces responses in the pharmacological treatment of inflammation, we performed differential analysis of the proteome of the mouse macrophage RAW264.7 cells in response to ASC. In this study, we used a proteomic analysis of LPS-induced RAW264.7 cells treated by ASC, to identify proteins potentially involved in inflammatory processes. The RAW264.7 cell proteomes with and without treatment with ASC were compared using two-dimensional electrophoresis (2-D SDS-PAGE), matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF-MS) and bioinformatics. The largest differences in expression were observed for the calreticulin (4-fold decrease), ${\beta}-actin$ (4-fold decrease) and vimentin (1.5-fold decrease). In addition, rabaptin was increased 3-fold in RAW264.7 cells treated with ASC. The expression of some selected proteins was confirmed by RT-PCR analysis.

• Journal of Life Science
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• v.18 no.6
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• pp.845-851
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• 2008

${\beta}-Lactamase$, secreted from Bacillus sp. J105 strain was purified to a single band on SDS-PAGE by ammonium sulfate precipitation, ion exchange column chromatography and gel-filtration. The molecular weight of the purified enzyme was 31 kDa on SDS-PAGE and its isoelectric point was 7.35. Optimal pH and temperature for enzymatic reaction were 5 and $40^{\circ}C$, respectively. As a result of total amino acid composition analysis of the purified enzyme, Gly and Ala were occupied 14.1 and 13.3 mole %, respectively. Km and Vmax value of purified enzyme were 1.33 mM and 0.36 mM/ml using ampicillin as a substrate, respectively.

• Parasites, Hosts and Diseases
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• v.26 no.4
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• pp.245-254
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• 1988

We studied the serological reaction between various antigenic components from Cysticercus cellulosae and IgG antibodies in sera of cysticercosis, sparganosis, hydatidosis patients and normal humans by ELISA and EITB. In serological tests by ELISA, we recognized cross reaction of Cysticercus antigenic components with IgG antibodies in heterologous sera such as sparganosis and hydatidosis patients or normal humans. The crude antigenic components of Cysticercus showed lower ELISA sensitivity in homologous sera from cysticercosis patients than heterologous sera from hydatidosis patients. A total of 31 polypeptide bands with 260 KDa~22 KDa molecular weights were detected by SDS-PAGE, and 11 of them showed strong intensity. Total 22 components of them were recognized by IgG antibodies in cysticercosis patients sera. However, 12 of them were recognized also by normal human sera, 11 were by sparganosis sera, and-21 were by hydatidosis patients sera. The crude antigenic components of 104 KDa, 82 KDa, 72 KDa, 59 KDa and 34 KDa molecular weights were nonspecific ones, which cross-reacted with sera of either cysticerco, =is, sparganosis, hydatidosis patients or normal humans.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.1
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• pp.117-123
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• 2008

The protein profiles of domestic potato cultivars were evaluated for total protein determination, amino acid composition, SDS-PAGE analysis and scanning densitometry. There were statistically significant differences in the levels of amino acids among potato cultivars. Total nitrogen amount was also significantly different among cultivars, ranging from 1.27 to 1.64%. SDS-PAGE analysis showed that there were significant differences in the content of major potato proteins such as papatin (40 kDa), trypsin inhibitor (20 kDa) and protease inhibitor (15 kDa) among cultivars (p<0.05). The amount of papatin among cultivars with a range of 22.16 to 25.81 mg/g d.w. was higher in Jopung, Shepody and Superior, whereas the amount of protease inhibitors including 15 kDa and 20 kDa was the highest in Jopung (37.0%). The Shepody contains the highest amount of papatin (25.8%) and the lowest of trypsin inhibitor (5.22%). Thus, it is suggested that Shepody is the most desirable cultivar for better nutrition based on the protein profile.

• Korean Journal of Agricultural Science
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• v.22 no.1
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• pp.82-95
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• 1995

These experiments were carried out to isolate SIgA from human and bovine milk. The immunochemical properties of SIgA from human and bovine milk were examined by Gel filtration, DEAE and SDS-PAGE. Double Immunodiffusion, and Immunoelectrophoresis. The results obtained are as follows: 1. Human SIgA was purified from colostrum of Korean women by repeated gel filtration on Sephadex G-200 and Sepharose 6B, but bovine SigA was not cleary purified from bovine colostrum of Holstein cows by anion exchange chromatography using DEAE-Sephadex A-50 and gel filtration on Sephadex G-200 and Sepharose 6B. 2. The immunochemical properties of fractions from gel filtration on the Sephadex G-200 and Sepharose 6B column as assessed by Immunoelectrophoresis and double Immunodiffusion to identify the presence of IgM in first peak fraction, and the presence of pure SIgA in second peak fraction. However, Bovine SigA rich fraction from bovine colostrum of Holstein cows contained a large amount of $IgG_1$-dimer in addition to SIgA. 3. The fragments of reduced bovine colostrum SIgA rich fraction were estimated to have molecular weights of secretory component, heavy chain and light chain (75,000-80,000, 50,000-60,000, 25,000-27,000 daltons) by SDS-PAGE, respectively. Those were similar to the molecular weight of reduced SIgA from human milk.

• KSBB Journal
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• v.16 no.2
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• pp.188-199
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• 2001

A gene encoding the dextransucrase(dsCB) that synthesizes mostly $\alpha-(1\rightarrow6)$ linked dextran with low amount(10%) of $\alpha-(1\rightarrow3)$ branching was cloned and sequenced from Leuconostoc mesenteroides B-742CB. The 6.1 kbp DNA fragment carrying dsCB showed one open reading frame(ORF) composed of 4,536bp. The deduced amino acid sequence shows that it begins from the start codon(ATG) at position 698 of the cloned DNA fragment and extends to the termination condon(TAA) at position 5,223. The enzyme is consisted of 1,508 amino acids and has an calculated molecular mass of 168.6kDa. This calculated Mw was in good agreement with an activity band of 170kDa on non-denaturing SDS-PAGE. A recombinant E. coli DH5 $alpha$ harboring pDSCB produced extracellular dextransucrase in 2% sucrose medium, and synthesized both soluble and insoluble dextran. To compare the properties of enzyme with B-742CB dextransucrase, the acceptor reaction, hydrolysis of dextran and methylation were performed. The expressed enzyme showed the same properties as B-742CB dextransucrease, but its ability to synthesize $\alpha-(1\rightarrow3)$ branching was lower than that of B-742CB dextransucrase. In order to identify the critical amino acid residues known as conserved regions related to catalytic activity, Asp-492 was replaced with Asn. D492N resulted in a 1.6 fold decrease in specific activity.