• The Journal of the Korean Society for Microbiology
• /
• v.22 no.2
• /
• pp.117-123
• /
• 1987

Previous studies have been performed for the sero-identification of selected species of Bacteroides by immunofluorescence antibody techniques and enzyme-linked immunosorbent assay using species-specific rabbit antisera to B. gingivalis, B. intermedius, and B. melaninogenicus. However, these studies have not commented on the serological cross-reactivity between these 3 species of black- pigmented Bacteroides. For the cross-reactivity study, antisera to B. gingivalis ATCC 33277, B. intermedius ATC C25261 and B. asaccharolyticus ATCC 25260 were raised from rabbits. Preliminary study for observing the cross-reactivity between these species was performed by indirect immunoflourescence technique. Immunoabsorption of the antisera was done with bacterial cells from the other species and the species-specificity of the antisera was conformed by the absence of reactivity with bacterial strains from the other species by indirect immunofluorescence technique and enzyme-linked immunosorbent assay. Three representative unabsorbed antisera cross-reacted strongly with cells from the other species. Especially, anti-B. asaccharolyticus ATCC 25260 antiserum showed a strong cross-reactivity with B. gingivalis ATCC33277. After immunoabsorption of 3 representative antisera with the other species, the cross-reactivity was found only between B. gingivalis ATCC 33277 and B. asaccharolyticus ATCC 25260. Further study would be necessary to clarify the cross-reactivity between important oral black-pigmented Bacteroides from subgingival plaque or bacterial colonies for rapid identification.

• Journal of Microbiology and Biotechnology
• /
• v.11 no.5
• /
• pp.884-886
• /
• 2001

The reactivity and stability of purified Lignostilbene- ${\alpha}$,${\beta$}-dioxygenase (LSD)-I were examined. Its optimum temperature was $50^{\circ}C$ at pH 8.5, but it was stable only up to $30^{\circ}C$. The activity of LSD-I increased 12-fold by $30\%$, with increased $V_{max}$ and lowered $K_m.$ LSD-I was stable in 10% methanol.

• Journal of Food Hygiene and Safety
• /
• v.6 no.3
• /
• pp.111-117
• /
• 1991

We examined to develop the enzyme linked immunosorbent assay (ELISA) for determination of zearalenone in animal feeds. Zearalenone was first converted to 6'-(carboxymethyl) zearalenone oxime(zearalenone oxime) to get a coupling site and then conjugated to bovine serum albumin(BSA) for use as immunogen and to horseradish peroxidase(HRP) for use as enzyme marker. Antibody against zearalenone was obtained after 11 weeks of immunization of rabbit with zearalenone oxime-BSA. Cross reactivity of the antibody with ${\alpha}-zearalanol,\;{\beta}-zearalenol,\;{\alpha}-zearalanol\;and\;{\beta}-zearalanol$ were 168, 46, 26 and 20% respectiviely. A simple procedure was devised for the screening of zearalenone in feeds using ELISA. Feeds samples(5g) were extracted by blending with 25 ml of methanol-phospate butTered saline-dimethylformate(70 : 29 : 1) and the extract was filtered and aqueous filterate analyzed. It took only 1 hours to do whole procedure for the analysis of zearalenone in feeds by the direct competitive ELISA, and detectable limit was 1-100 ppb. Using this procedure, only 4 of 24 feed samples showed positive results with 3.93-7.43 ppb levels.

• YAKHAK HOEJI
• /
• v.31 no.2
• /
• pp.64-69
• /
• 1987

Monoclonal antibodies against human chorionic gonadotropin (hCG) were prepared and characterized by examining isotype, epitope binding, cross reactivity and affinity constants. And a sandwich type enzyme immunoassay for native hCG was developed with solid phase monoclonal antibody against the conformational determinant expressed only on native hCG and horseradish peroxidase conjugated monoclonal antibody against the $\beta$-subunit of hCG. The assay was sensitive to 1 mIU hCG/ml and shown a linear response up to 200 mIU hCG/ml. The cross reactivity for luteinizing hormone and $\beta$-subunit of hCG were 1% and 0.18%, respectively.

• Biomedical Science Letters
• /
• v.12 no.3
• /
• pp.225-231
• /
• 2006

Fibrinolytic enzyme was purified from the fruiting bodies of Lepista nuda, using DEAE-Cellulose chromatography, Phenyl Sepharose chromatography, and Mono-S column chromatography. The substance has a molecular weight of 30006.62 Da as measured by MALD-TOF mass spectrometry. The N-terminal amino acid sequence of the enzyme was Tyr-Pro-Ser-Pro-Ser-His-Gln-Thr-Ala-Val-Asn-Ala-Ile-Ile-X. The activity of the enzyme was inhibited by PMSF, indicating that the enzyme is a serine protease. No inhibition was found with E-64, pepstatin, and EDTA. It has broad substrate specificity for synthetic peptides. The enzyme was stable up to $30^{\circ}C$. The enzyme hydrolyzes both Aa and y chains of human fibrinogen but did not show any reactivity for $B{\beta}$ chain of human fibrinogen.

• Journal of Microbiology and Biotechnology
• /
• v.13 no.5
• /
• pp.794-799
• /
• 2003

Enzyme-linked immunosorbent assay (ELISA) was developed for the rapid detection of Fusarium species, known as harmful fungi in food. One of the hybridoma cell lines (lB8) which produced a monoclonal antibody (Mab) specific to Fusarium extracellular polysaccharide (EPS) was screened and the Mab was produced and purified. A detection limit of the sandwich ELISA against F. moniliforme EPS was $0.001\;\mu\textrm{g}/ml$ in the standard curve. Among the 59 strains tested, most Fusarium species showed hight reactivity with Mab lB8, even when the culture broths were diluted 100,000 times. On the other hand, the other genera, except A. versicolor and Trichoderma viride, had no reactivity. When 1 to $100\;\mu\textrm{g}$ of F. moniliforme EPS was spiked into rice, potato, and mandarine orange, the average recoveries were 151%, 84%, and 94%, respectively, determined by sandwich ELISA. The correlation coefficients between the EPS levels determined by sandwich ELISA and the dry mycelial weight of the liquid culture of F. moniliforme, as well as between the EPS and colony forming unit in solid culture of potato, were 0.97 and 0.91, respectively.

• Bulletin of the Korean Chemical Society
• /
• v.23 no.7
• /
• pp.985-989
• /
• 2002

For efficient biopulping process, very active and stable lignase is essential. Laccase is one of the best enzyme in terms of environmentally benign processes, since the enzyme uses oxygen as an oxidant to degrade lignin and produces no hamful prod ucts. We could purify a laccase homogeneously from Cerrena unicolor in a very active state. It shows characteristic absorption feature with blue band at λmax = 604 ㎚. Molecular weight of the enzyme is 57,608 which could be accurately determined by MALDI/TOF MS. The enzyme has 2.8 copper ions per enzyme implying apoenzymes might exist together. The enzyme is active in lignin degradation and the activity increases 4 times in the presence of ABTS as a mediator.

• Archives of Pharmacal Research
• /
• v.20 no.2
• /
• pp.115-121
• /
• 1997

Ile-269 in horse liver alcohol dehydrogenase isoenzyme S(HLADH-S) was mutated to serine by phosphorothioate-based site-directed mutagenesis in order to study the role of the residue in coenzyme binding. The specific activity of the mutant(1269S) enzyme to ethanol was increased 49-fold. All turnover numbers of 1269S enzyme toward 9 primary alcohols were increased. The mutant enzyme showed 3.6, 4.6, 11.6-fold higher catalytic efficiency for $5{\beta}$-androstane-3, 17-dione, $5{\beta}$-cholanic acid-3-one and retinal than wild-type, respectively. The reaction mechanism of 1269S enzyme was ordered bi bi as wild-type's. These results indicate that the hydrophobic interaction of Ile-269 residue with coenzyme plays an important role in dissociation of coenzyme from enzyme-coenzyme complex, which has been known as the rate limiting step of ADH reaction.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.43 no.4
• /
• pp.228-233
• /
• 1998

Seed storage proteins have been used for studying biochemical genetics and end-use quality aspects. We conducted enzyme-linked immunosorbent assay (ELISA) and one-dimensional SDS-PAGE (1D SDS-PAGE) to evaluate different cereal crop species and Korean wheat lines for rye secalin proteins. The antisecalin antibody showed consistent specificity for rye secalin with little cross-reactivity to gliadins. Immunological cross-reactivities measured by the ELISA technique using competition assay showed significant differences of absorbance among rye, triticale, wheat-rye translocated wheat and non-translocated wheat. The absorbance values were lowest in rye followed by triticale, translocated wheat and non-translocated wheat. The ELISA for discrimination of wheat-rye translocation on the basis of antigen-antibody reactivity showed that none of the Korean wheat lines possessed 1RS and secalin proteins. The competitive ELISA experiment demonstrated specific determination for secalin that was originated from rye chromosomal parts. The result of 1D SDS-PAGE for identifying rye secalin subunits showed all three rye specific secalin protein subunits (75 KDa, 45 KDa, and 40 KDa) for rye and triticale, and 1RS specific secalins (45 KDa and 40 KDa) for 1AL/1RS and 1BL/1RS translocated wheats. All Korean wheats were lacking 1RS of rye chromosome and secalin.

• Journal of Microbiology and Biotechnology
• /
• v.14 no.2
• /
• pp.385-389
• /
• 2004

The antibody-mix sandwich enzyme-linked immunosorbent assay (Ab-mix sELlS A) system was developed in order to simultaneously detect the extracellular polysaccharide (FPS) of Aspergillus, Penicillium, or Fusarium species using one detection system. The detection limit and detection range of the Ab-mix sELISA towards EPS of Penicilliun citrinum were not changed, and those towards Fusarium moniliforme EPS were changed a little compared to that of individual sandwich ELISA [9, 10]. The fungal culture filtrates of Aspergillus and Penicillium species showed nearly similar reactivity towards Ab-mix sELISA as that of sELISA using the MAb lB8 alone [9]. Also, the fungal culture filtrates of Fusarium species showed nearly the same reactivity towards Ab-mix sELISA as that of sELISA using the MAb lB8 alone [10]. Thus, this ELISA system showed that the three genera of molds, Aspergillus, Penicillium, or Fusarium, which are three major important molds producing mycotoxins in food or agricultural commodities, could be detected at the same time, using one detection system.