• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.7
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• pp.1169-1174
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• 2004

This study was carried out to assess the effects of electron beam (EB) radiation on the conformational changes of ovalbumin (OVA), based on the early works using gamma irradiation. The applied doses of OVA used were 3,5,7, and 10 kGy, respectively. The conformational alterations were measured with SDS-PAGE, GPC-HPLC, and competitive indirect enzyme-linked immunosorbent assay (Ci-ELISA) using monoclonal anti-OVA IgG antibody. Irradiation caused a degradation and/or an aggregation of OVA molecule. Immunochemical structures of irradiated OVA were altered by irradiation. Effects of gamma and electron beam radiation were similar at the same absorbed doses. These results may be used for inhibition of food allergy and development of immunogen with EB radiation.

• Korean Journal of Pharmacognosy
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• v.32 no.1 s.124
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• pp.31-38
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• 2001

A lectin was purified from Allomyrina dichotoma (ADL) by physiological saline extraction, ammonium sulfate fractionation, anion exchange column chromatography on DEAE Sephadex A-50 and gel filtration column chromatography on Sephadex G-200. Several biochemical properties of ADL were characterized as follows: ADL from gel filtration column chromatography showed single band on SDS-PAGE. ADL agglutinated the erythrocytes of rabbit and human A, B, O, AB. Agglutinability was relatively stable at basic pH, and was stable at temperature below $40^{\circ}C$. Agglutinability was not affected by metal ions and EDTA. This lectin was proved to be a glycoprotein which contains 0.47% of sugars. The molecular weight of ADL was estimated to be 97,000 dalton by SDS-PAGE. By amino acid analysis, ADL exhibited high amounts of aspartic acid. The lectin's immunomodulating effect was measured as cytokine production. The productions of 5 cytokines $(IL-1{\alpha},\;IL-2,\;IL-6,\;IFN{\gamma}\;and\;TNF{\alpha})$ from peripheral blood mononuclear cells were measured by ELISA. The lectin induced the highest secretion of IL-2 at 8 hr, $TNF{\alpha}$ at 4 hr, and $IFN{\gamma}$ at 24hr, respectively. These results suggest that ADL can elicit the production of detectable cytokines from PBMC.

• Journal of agricultural medicine and community health
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• v.16 no.1
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• pp.70-78
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• 1991

Antibody changes in experimental anisakiasis were observed by ELlSA and SDS-PAGE/EITB using various antigens : whole worm extract antigen(WWE), somatic antigen(SOM), excretory-secretory antign(ES), and hemoglobin antigen(HB) of Anisakis Type 1. The results obtained were as follows. l) Serum levels of IgG antibody by ELISA increased from 1st week of infection and reached their maximum titer at 5th week after infection, and decreased gradually thereafter. 2) The best result expressed as positive/negative ratio could be obtained when ES antigen was used. 3) Silver stained SDS-PAGE of each antigen showed at least 20 protein bands : In WWE, 286, 278, 262, 38, 18 Kd bands ; In SOM, 38 Kd band : In ES, 286, 65, 13 Kd bands ; In Hb, 61, 55, 38, 28, 26, 22, 20, 16, 15 Kd bands iepntibied as were major bands. 4) By EITB using WWE, Serum antibody recognized major protein with molecular weight of 86 Kd and 16 Kd. Using ES, 69, 59, 16 Kd bands were observed and using Hb, 28 Kd band was observed as specific band. In conclusion, excretory-secretory antigen(ES) of Anisakis larvae was most usable for ELISA.

• Journal of Life Science
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• v.18 no.3
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• pp.350-356
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• 2008

Biochemical characterization including hemagglutination of erythrocytes, molecular weight, optimum temperature, thermal stability, optimum pH, carbohydrate specificity, and inhibitory effect of metal ion were studied in lectin of eggplant (Solanum melongena L.) fruit prepared by ammonium sulfate fractionation and affinity chromatography. This lectin was agglutinated by trypsin-treated rat blood erythrocyte. The molecular weight of this lectin by SDS-PAGE was estimated to be approximately 19.3 kDa of a single band. This lectin has no activity by 7 carbohydrates containing D-glucose. The optimum range of temperature and pH were $10-20^{\circ}C$ and pH 6.2-7.2, respectively. This lectin was relatively stable at $20-70^{\circ}C$. And the activity of this lectin was not inhibited by $Ca^{2+},\;Co^{2+},\;Cu^{2+},\;Fe^{2+},\;Mg^{2+}$, and $Mn^{2+}$.

• Parasites, Hosts and Diseases
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• v.34 no.2
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• pp.135-142
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• 1996

Antigenic domain of jai or surface protein (p30) of Toxoplosmc Sondii was analyzed after polymerase chain reaction (PCR) of its gene fragments. Hydrophilic or hydrophobic moiety of amino acid sequences were expressed as glutathione S-transferase (G57) fusion proteins. Fragments of p30 gene were as follows: 737, total p30 open reading frame (ORF) ; S28, total ORF excluding N-terminal signal sequence and C-terminal hydrophobic sequence; Al9, N-terminal 2/3 parts of A28; A19, N-terminal 2/3 of S28; P9, C-terminal 2/3 part of S28; Z9. middle 1/3 of S28; and 29, C-terminal 1/3 of S28. respectively. Primer of each fragment was synthesized to include clamp sequence of EcoR I restriction site. PCR amplified DNA was inserted info GST (26 kDa) expression vector, PGEX-47-1 to transform into Escheri,hia coei (.JM105 strain). G57 fusion proteins were expressed with IPTG induction as 63. 54, 45, 45, 35, 36. and 35 kDa proteins measured by SDS-PAGE. Each fusion protein was confirmed with G57 detection kit. Western blot analysis with the serum of a toxoplasmosis patient revealed antigenicity in proteins expressed by T37. S28, and Al9 but not those by Pl8. X9, Y10, and Z9. Antigenicity of p30 seems to be located either in N-terminal 115 part in the presence of middle 1/3 part or in the oligopeptides between margins of the first and second 1/3 parts.

• Journal of Life Science
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• v.28 no.1
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• pp.78-82
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• 2018

Detection of pathogenic microorganisms takes several days by conventional methods. It is necessary to assess microorganisms in a timely manner to reduce the risk of spreading infection. For this purpose, bacteriophages are chosen for use as a biosensing tool due to their host specificity, wide abundance, and safety. However, their lytic cycle limits their efficacy as biosensors. Phage proteins involved in binding to bacteria could be a robust alternative in resolving this drawback. Here, a fragment of tail protein J (residues 784 to 1,132) of phage lambda fused with 6X His-tag (6HN-J) at its N-terminus was cloned, overexpressed, purified, and characterized for its binding with microorganisms. The purified protein demonstrated a size of about 38 kDa in sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE) and bound with anti-His monoclonal antibodies. It bound specifically to Escherichia coli K-12, and not Salmonella typhimurium, Bacillus subtilis, or Pseudomonas aeruginosa in dot blotting. Binding of the protein to E. coli K-12 inhibited about 50% of the in vivo adsorption of the phage lambda to host cells at a concentration of $1{\mu}g/ml$ 6HN-J protein and almost 100% at $25{\mu}g/ml$ 6HN-J. The results suggest that a fusion viral protein could be utilized as a biosensing element (e.g., protein chips) for detecting microorganisms in real time.

• Food Science and Preservation
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• v.9 no.4
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• pp.429-433
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• 2002

The D-xylulokinase from Candida sp. L-16 was purified through a sequence of ammonium sulfate fractionation, DEAE-cellulose chromatography, Sephadex G-100 and Sephadex G-200 gel filtration. The specific activity of the purified Dxylulokinase was increased to 23.2 fold and the yield was 11.2%. The enzyme was showed to be a single protein band by SDS-PAGE. The molecular weight of the enzyme was 150,000 dalton, this enzyme was identified to be a dimer with two subunits. The optimum conditions of the enzyme were pH 8.0 and 40$\^{C}$, respectively. The enzyme was relatively stable between pH 7.0 to pH 9.0, but it was unstable over 30$\^{C}$. The enzyme showed substrate specificity on D-xylulose, D-arabinose and D-ribose, Km value and Vmax for D-xylulose were 0.042 mM and 117 units/ml, respectively. The activation energy of the enzyme was 4.75 Kcal/mol. The one was inhibited by metabolic intermediates such as 6-phosphogluconic acid, 2-keto-gluconic acid. The enzyme was activated by EDTA and thiol compounds such as cysteine-HCI, DTT and glutathione.

• Korean Journal of Environmental Biology
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• v.19 no.4
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• pp.302-312
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• 2001

Immunoglobulin G was purified by 40% $(NH_4)_2SO_4$ precipitation, DEAE-Sephadex, Sephadex G-150 column chromatographies from rabbit antiserum against V. vulnificus ATCC 27562 O antigen and used for immunological test for V. vulnificus isolates. The profiles of cell lysate total protein and outer membrane protein from the isolates were analyzed by SDS-PAGE and densitometry. The overall profiles in all isolates were similar. Distict protein band was observed in comparison with V. parahaemolyticus. Western Blotting with rabbit Immunoglobulin G against cell lysates and OMP of V. vulnificus isolates showed a strong antigenic response to antigen 66, 60, 54, 48, 33 and 26 kDa which were common to all strains examined. The 26 kDa antigen showed V. vulnificus specific antigen in comparison with Vibrio parahaemolyticus. A sandwich enzyme-linked immunosorbent assay was developed by using rat anti-V. vulnificus ATCC 27562 polyclonal antibodies as capture antibody, a purified rabbit IgG antibody as detector antibody, and goat anti-rabbit IgG-alkaline phosphatase conjugate as developer antibody. When four V. vulnificus isolates were tested, the reactivity showed from 50 to 70% by sandwich ELISA.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.2
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• pp.351-357
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• 1997

The cyclodextrin glycosyltransferase(EC 3.2.1.19) from Bacillus firmus was purified by precipitating with ammonium sulfate followed by, DEAE-Sephadex A-50 column chromatography and Sephadex G-100 column chromatography. In this way, we were able to obtain the single band protein on SDS-PAGE with a yield of 12%, whose purity was 49 fold. The purified CGTase was identified as a protein having molecular weight of approximately 80,000 dalton and isoelectric point of 9.6. The optimum pH and temperature for the enzyme activity were 8.0 and $65^{\circ}C$, respectively. The enzyme was stable at between pH 5.5 and 9.0 and up to $50^{\circ}C$. After 24hr of enzyme reaction using soluble starch as substrate, the ratio of ${\alpha}-$, ${\beta}-$ and ${\gamma}-cyclodextrin$ production was 0.01 : 2.90 : 1.00, respectively. And this CGTase pro-duced mainly ${\beta}-$ and ${\gamma}-cyclodextrin$.

• Parasites, Hosts and Diseases
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• v.26 no.3
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• pp.163-168
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• 1988

To observe the antigenic protein fractions in saline extract of Spirometra mansoni plerocercoid (sparganum), the crude extract was separated in reducing conditions of sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE). The proteins, transferred by celctrophoresis to introcillulose paper, were reacted with sera from 15 surgically confirmed sparganosis and 24 cysticercosis patients for immunoblotting. Out of 30 identified protein bands in the extract, bands of 29 and 36 kilodaltons (kDa) were the strongest and the most frequently reacting with specific antibody (IgG) in sparganosis sera. Bands of highter molecular weight also reacted with the sera but their frequency of reactions was lower. Sera of cysticercosis reacted with different protein bands in saline extract of sparganum, but the cross reactions were observed in strong antigenic bands of 29 and 36 kDa.