• Journal of Microbiology and Biotechnology
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• v.15 no.2
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• pp.239-246
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• 2005

Some characteristics of two forms of glucoamylase (glucan 1 A-$\alpha$-glucosidase, EC 3. 2. I. 3) purified from Aspergillus coreanus NR 15-1 were investigated. The enzymes were produced on a solid, uncooked wheat bran medium of A. coreanus NR 15-1 isolated from traditional Korean Nuruk. Two forms of glucoamylase, GA-I and GA-II, were purified to homogenity after 5.8-fold and 9.6-fold purification, respectively, judged by disc- and SDS-polyacrylamide gel electrophoresis. The molecular mass of GA-I and GA-II were estimated to be 62 kDa and 90 kDa by Sephadex G-1OO gel filtration, and 64 kDa and 91 kDa by SDS-polyacrylarnide gel electrophoresis, respectively. The optimum temperatures of GA-I and GA-II were 60$^circ$C and 65$^circ$C, respectively, and the optimum pH was 4.0. The activation energy (Ea value) of GA-I and GA-II was 11.66 kcal/mol and 12.09 kcal/mol, respectively, and the apparent Michaelis constants (K_{m}) of GA-I and GA-II for soluble starch were found to be 3.57 mg/ml and 6.25 mg/ml, respectively. Both enzymes were activated by 1 mM Mn^{2+} and Cu^{2+}, but were completely inhibited by 1 mM N­bromosuccinimide. The GA-II was weakly inhibited by 1 mM p-CMB, dithiothreitol, EDTA, and pyridoxal 5-phosphate, but GA-I was not inhibited by those compounds. Both enzymes had significant ability to digest raw wheat starch and raw rice starch, and hydrolysis rates of raw wheat starch by GA-I and GA-II were 7.8- and 7.3-fold higher than with soluble starch, respectively.

• Journal of Life Science
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• v.22 no.1
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• pp.98-109
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• 2012

The properties of lactate dehydrogenase (EC 1.1.1.27, LDH) and expression of monocarboxylate transporters (MCTs) 1, 2, and 4 were studied in tissues from Micropterus salmoides. Native-PAGE revealed that the LDH $A_4$ isozyme was predominantly located in skeletal muscle. The LDH $A_4$, $A_2B_2$, and $B_4$ isozymes were detected in heart, liver, eye, and brain tissues, while eye-specific $C_4$ isozyme was detected in eye tissue. In September, strong LDH $B_4$ isozyme activity was detected in heart tissue. High $A_4$ isozyme activity was noted in all other tissues except heart tissue. However, in November, strong $A_4$ isozyme activity was detected in heart tissue. The LDH/CS (Citrate synthase, EC 4.1.3.7) ratio in skeletal muscle and heart tissues indicated that anaerobic metabolism was high in those tissues. Native-PAGE after immunoprecipitation showed that eye-specific $C_4$ isozyme was more similar to the $A_4$ than the $B_4$ isozyme. The LDH $A_4$ isozyme was purified by affinity chromatography. The molecular weight of subunit A was 37,200. The LDH activity in tissues was consistently 11.05~28.32% due to inhibition by 10 mM pyruvate. The $K_m^{PYR}$ of LDH in eye tissue was very low. The optimum pH for LDH in tissues was pH 7.5~8.0. The LDH $A_4$ isozyme was detected in mitochondria of skeletal muscle, whereas the $B_4$ and $A_2B_2$ isozymes were detected in heart tissue mitochondria. Western blot analysis indicated that MCTs 1, 2, and 4 were located in the plasma membrane and mitochondria of skeletal muscle and heart tissues. The sizes of MCTs 1, 2, and 4 in skeletal muscle were 60, 54~38, and 63 kDa, while those in heart tissue were 57, 54~38, and 55.5 kDa, respectively. In conclusion, M. salmoides appears to use anaerobic metabolism predominantly when adapted to a hypoxic environment. In highly activated skeletal muscle and heart tissue, energy production is controlled by inward and outward flows of pyruvate and lactate through MCTs 1, 2, and 4 in the plasma membrane and mitochondria, with effective adjustment by LDH isozymes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.4
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• pp.398-406
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• 1992

In order to develop a new flavourant using the fish skin gelatin, the proteolytic renditions for the gelatin hydrolysate of the alkali (B-type) and Alcalase (E-type) pretreated flounder (Limanda aspera) skin gelatin were investigated, and some physical properties, molecular weight and amino acid compositions of the hydrolysates were, also, compared with each other. The proteolytic conditions of the gelatins (B-type and E-type) by trypsin were as follows : reaction temperature, 55$^{\circ}C$ : pH, 9.0 : enzyme concentration, 0.1% : re-action time, 4hrs for B-type and 1 hr for E-type. The degrees of hydrolysis of the B-type and E-type gelatin un-der the renditions stated above were 63% and 82%, respectively. The rnajor molecular weights of the hydrolysates were 15,000 dalton for B-type and 12,400 dalton for E-type. Among the amino acids in the hydrolysates, glycine, alanine, proline, hydroxyproline and serine having a sweet taste were responsible for 57% of the total amino acid. But valine, leucine, phenylalanine, tyrosine, methionine, arginine and histidine having a bitter taste were only 18%.

• Journal of Microbiology and Biotechnology
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• v.21 no.12
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• pp.1211-1227
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• 2011

C57BL/6J mice have been widely used as a diet-induced obesity model because they trigger common features of the human metabolic syndrome. In the present study, C57BL/6J male mice were fed either a high-fat diet (HFD) or normal diet (ND) during a 24-week period, and then the age-dependent liver proteome of mice in two groups was analyzed using 2-DE combined with MALDI-TOF-MS. Among identified proteins, up-regulated proteins were subdivided to early (during the first 4 weeks) and late (20~24 weeks) markers that played a role in diet-induced obesity development. Important early markers included ketohexokinase and prohibitin, and late markers included the 75 kDa glucose-regulated protein, citrate synthase, and selenium-binding liver protein. Of these, the 75 kDa glucosere-gulated protein has already been linked to obesity; however, prohibitin protein involved in obesity was identified for the first time in this study. In order to validate the proteomic results and gain insight into metabolic changes between the two groups, we further confirmed the expression pattern of some proteins of interest by Western blot analysis. Combined results of proteomic analysis with Western blot analysis revealed that antioxidant enzymes were progressively decreased, whereas cytoskeletal proteins were time-dependently increased in HFD mice.

• The Korean Journal of Mycology
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• v.31 no.3
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• pp.168-174
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• 2003

In this study, Cordyceps militaris was grown in a liquid medium containing colloidal chitin. A chitinase was purified from the supernatant or cultured medium by ammonium sulfate fractionation, DEAE-Sephadex A-25 and Sephadex G-50 column chromatography. Optimum temperature and pH of this enzyme were $35^{\circ}C$ and 5.5, respectively. The molecular weight of the chitinase was estimated to be 48.5 kDa by SDS-PAGE and its Km value was 0.57 mM. The activity of this enzyme was inhibited by $Cu^{2+},\;Mn^{2+},\;Hg^{2+},\;Zn^{2+},\;CO_{3}^{2-},\;SO_4^{2-},\;CN^-,\;ion,\;and\;OCN^-$ maleic anhydride, acetic anhydride or N-bromo succinimide, especially strongly inhibited by sodium cyanate for 84.0 percentage. But its activity wag slightly stimulated by $Mg^{2+}\;and\;K^+$ ion, respectively. The products formed during hydrolysis of the hexa-N-acetylchitohexaose with this enzyme were N,N'-diacetylchitobiose and N,N',N'-triacetylchitotriose. These results imply that this purified enzyme may be an endo-chitinase.

• Parasites, Hosts and Diseases
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• v.27 no.2
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• pp.131-140
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• 1989

Sera from confirmed patients of 5 hydatidosis, 67 neurocysticercosis and 89 other parasitic diseases were tested for specific antibody (IgG) levels by ELISA to cystic quid antigens from metacestodes of Echinococcus granuzosus (HF) and Taenia sodium (CF). All hydatidosis sera reacted positively to both HF and CF while neuro- cysticercosis sera did in 49.3% to HF and 85.1% to CF, The frequencies of cross- reactions were lower in other parasitic diseases to both antigens, By SDS-PAGE, protein bands of 64, 35, 22 and 7 kilodaltons (kDa) were found common in HF and CF. SDS-PAGE/immunoblot exhibited that hl·datidosis sera reacted crossly to CF at 135, 110, 100, 86, 64, 45, 39, 35 and 24 kDa bands while neurocysticercosis sera did to HF at 135, 100, 86, 64, 52, 39, 35, 29 and 24 kDa bands. These results indicated that protein bands of 135, 100, 86, 64, 39, 35 and 24 kDa were major common components in HF and CF. Protein bands of 7 kDa in HF and 15, 10 and 7 kDa in CF did not react crossly and were specific components in respective antigens.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.5
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• pp.333-341
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• 2001

The Compost-decomposing-bacteria was isolated from livestock compost containing sawdust. The isolated bacteria was identified as Bacillus subtilis LYH201 by the method of the composition of the fatty acid with MIDI system and Bergey's manual. Cloning of CMCase encoding gene was accompanied by shotgun method. The pLK100 have yellow activity ring on CMC medium, that was carried 2.2 kb insert DNA in pBluescript II $SK^+$ vector, named BglC gene. The BglC was very similar to Pectobacterium carotovorum Gun_CLOAB(P15704) with score of 57% identity and 71% homology over 508 aa. The BglC was measured molecular weight 56 kDa by CMC-SDS-PAGE. Optimum cellulase activity Bacillus subtilis LYH201 was temperature $50^{\circ}C$ and pH 7.

• Journal of Plant Biotechnology
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• v.4 no.2
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• pp.59-65
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• 2002

ADP-glucose pyrophosphorylase (AGPase) catalyzes the key regulatory step in starch biosynthesis. Two cDNA clones encoding AGPase subunits were isolated from the leaf cDNA library of Chinese cabbage (Brassica campestris L. spp. pekinensis). One was designated as BCAGPS for the small subunit and the other as BCAGPL for the large subunit. Both cDNAs have uninterrupted open reading frames deriving 57 kDa and 63 kDa polypeptides for BCAGPS and BCAGPL, respectively, which showed significant similarity to those of other dicot plants. Also, However, the deduced amino acid sequence of BCAGPL has a unique feature. That is, it contains two regions (Rl and R2) lacking in all other plant enzymes. This is the first report of BCAGPL containing Rl and R2 among plant large subunits as well as small subunits. From the genomic Southern analysis and BAC library screening, we inferred the genomic status of BCAGPS and BCAGPL gene.

• Food Science and Biotechnology
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• v.15 no.4
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• pp.534-542
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• 2006

The effects of ethanol fractions of three different rice grain extracts, Jakwangchalbyeo, Hwasunchalbyeo, and Ilpumbyeo, on apoptotic cell death in the rat hepatoma H4IIE cell line were investigated using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] cell viability assay. One hundred mg/mL Jakwangchalbyeo extract significantly reduced cell viability to 69.5, 57.2, and 46.1% within 24, 48, and 72 hr, respectively. Fluorescence-activated cell sorting (FACS) analyses were also performed to characterize the cell death pattern caused by treatment with the rice grain extracts. Apoptotic cell death was clearly observed with time after treatment with the Jakwangchalbyeo extract. In Western blotting analysis, degradation of the 116 kDa poly-ADP-ribose polymerase (PARP) molecule was observed with concomitant formation of an 89 kDa product 24, 48, and 72 hr after treating cells with the Jakwangchalbyeo extract. This indicates that an apoptotic process caused cell death in these cells. In conclusion, red-pericarp Jakwangchalbyeo extract induced apoptotic cell death in H4IIE cells to a larger extent than the other rice extracts.

• Parasites, Hosts and Diseases
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• v.44 no.1 s.137
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• pp.43-48
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• 2006

Experimental murine models with high, intermediate and low levels of genetically based susceptibility to Leishmania major infection reproduce almost entire spectrum of clinical manifestations of the human disease. There are increasing non-comparative studies on immune responses against isolated antigens of L. major in different murine strains. The aim of the present study was to find out whether there is an antigen that can induce protective immune response in resistant and susceptible murine strains. To do that, crude antigenic extract of procyclic and metacyclic promastigotes of L. major was prepared and subjected to SDS-PAGE electrophoresis. Western-blotting was used to search for antigen(s) capable of raising high antibody level of IgG2a versus IgG1 in the sera of both infected resistant and susceptible strains. Two novel antigens from metacyclic promastigotes of L. major (140 and 152 kDa) were potentially able to induce specific dominant IgG2a responses in BALB/c and C57BU6 mice. The 2 antigens also reacted with IgG antibody of cutaneous leishmaniasis patients. We confirm that 140 and 152 kDa proteins of L. major promastigotes are inducing IgG production in mice and humans.