• Journal of Microbiology and Biotechnology
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• v.17 no.11
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• pp.1898-1903
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• 2007

We attempted to modulate the overall protein expression rate through the addition of a repressor against the araBAD promoter system of Escherichia coli, in which glucose was used as a repressor. Therefore, 0.5% L-arabinose was initially contained as an inducer in culture medium, and either 2% glucose or 2% glycerol was used as a carbon source, and it was found that the expression of recombinant interferon-${\alpha}$ could be observed at the beginning of the batch culture when glycerol was used as a carbon source. However, when glucose was used, the initiation of recombinant interferon-${\alpha}$ expression was delayed compared with that when glycerol was used. Furthermore, when the addition of 0.5% glucose was carried out once or twice after 0.5% L-arabinose induction during DO-stat fed-batch culture, the distributions of soluble and insoluble recombinant interferon-${\alpha}$ were modulated. When glucose was not added after the induction of L-arabinose, all of the expressed recombinant interferon-${\alpha}$ formed an inclusion body during the later half of culturing. However, when glucose was added after induction, the expressed recombinant interferon-${\alpha}$ did not all form an inclusion body, and about half of the total recombinant interferon-${\alpha}$ was expressed in a soluble form. It was deduced that the addition of glucose after the induction of L-arabinose might lower the cAMP level, and thus, CAP (catabolite activator protein) might not be activated. The transcription rate of recombinant interferon-${\alpha}$ in the araBAD promoter system might be delayed by the partial repression. This inhibition of the transcription rate probably resulted in more soluble interferon-${\alpha}$ expression caused by the reduction of the protein synthesis rate.

• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2303-2309
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• 2007

Expressed protein ligation (EPL) technique, joining recombinantly expressed proteins to polypeptides, has been widely adopted for addressing various biological questions and for drug discovery. However, joining two recombinant proteins together is sometimes difficult when proteins are expressed insoluble and unrefoldable, because ligation-active proteins via intein-fusion are obtainable when they are folded correctly. We overcame this limitation coexpressing target protein with additional methionine aminopeptidase (MAP) which enhances removal of the initiation methionine of recombinantly expressed protein. Our approach demonstrated that two domains of 46 kDa 5-Enolpyruvylshikimate-3-phosphate (EPSP) synthase, a target of herbicide glyphosate, were successfully joined by native chemical ligation, although its C-terminal domain was expressed as an inclusion body. The intein-fused N-terminal fragment of EPSP synthase (EPSPSN, residues 1-237) was expressed and the ligation-active thioester tagged N-terminal fragment (EPSPSN-thioester) was purified using a chitin affinity chromatography and mercapto-ethanesulphonate (MESNA) as intein thiolysis reagent. Its Cterminal fragment (EPSPSC, residues Met237-238CYS-427), expressed as an inclusion body, was prepared from an additional MAP-expressing strain. Protein ligation was initiated by mixing ~1 mM of EPSPSN-thioester with ~2 mM of EPSPSCCYS (residues 238CYS-427). Also we found that addition of 2% thiophenol increased the ligation efficiency via thiol exchange. The ligation efficiency was ~85%. The ligated full-length EPSP synthase was dissolved in 6 M GdHCl and refolded. Circular dichroism (CD) and enzyme activity assay of the purified protein showed that the ligated enzyme has distinct secondary structure and ~115% specific activity compared to those of wild-type EPSP synthase. This work demonstrates rare example of EPL between two recombinantly expressed proteins and also provides hands-on protein engineering protocol for large proteins.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.49 no.1
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• pp.26-29
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• 2016

This study investigated the effects of dietary inclusion of sea mud on growth and body composition of juvenile sea cucumber Apostichopus japonicus. In experiment 1, three experimental diets containing sea mud at the level of 0, 30 and 60% were prepared. After feeding trial for 7 weeks, survival was not significantly different among groups. Final mean weight of sea cucumber fed the experimental diet without sea mud supplementation was significantly higher than that of sea cucumber fed the diet containing 30 and 60% sea mud. In experiment 2, three experimental diets containing sea mud at the levels of 0, 15 and 30% were prepared. After feeding trial for 19 weeks, survival was not significantly different among groups. Final mean weight of sea cucumber fed the diet without sea mud supplementation was not significantly different from that of 15%, but was significantly higher than that of sea cucumber fed the diet containing 30% sea mud. It was concluded that dietary inclusion of sea mud may inhibit growth of sea cucumber.

• Journal of Animal Science and Technology
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• v.63 no.4
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• pp.778-789
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• 2021

The objective of this study is to investigate the effect of dietary glucose oxidase (GOx) supplementation on the reproductive performance, litter performance, total tract digestibility, and blood profile of lactating sows fed corn- wheat-based diet. A total of twenty multiparous sows (Landrace × Yorkshire) were allocated into one of four treatments with five replicates per treatment. The dietary treatments were as follows: CON (Basal diet), GO1 (basal diet + 200 U GOx/kg), GO2 (basal diet + 300 U GOx/kg), GO3 (basal diet + 400 U Gox/kg). Dietary GOx supplementation did not affect lactating sow's reproduction performance as well as body weight, backfat thickness, and body condition score during pre and post farrowing, and at weaning (p > 0.05). However, after farrowing to weaning period lactating sow's fed GOx supplement has linearly (p = 0.0196) decreased the bodyweight loss. While, there were no effects (p > 0.05) observed on sows backfat thickness loss, average daily feed intake, and estrus interval among treatment groups. Dietary supplementation of GOx has linearly improved the body weight gain (p = 0.049) and average daily gain (p = 0.040) of suckling piglets. The total tract digestibility of dry matter and nitrogen was linearly increased with the graded level of GOx supplement. Also, a linear effect was observed on the glucose and superoxide dismutase of blood profile with the dietary inclusion of GOx. In summary, our finding indicates that the dietary inclusion of GOx supplement with corn- wheat-based diet had a beneficial effect on the nutrient digestibility and blood profile of lactating sows and improved the growth performance of suckling piglets.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.219-227
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• 2008

Bacillus thuringiensis was isolated as a pathogen of the sotto disease of silkmoth larvae about a hundred years ago. Since then, this bacterium has attracted attentions of not only insect pathologists but also many other scientists who are interested in its strong and specific insecticidal activity. This has led to the recent worldwide development of B. thuringiensis-based microbial insecticides and insect-resistant transgenic plants, as well as a landmark discovery of par asp orin, a cancer cell-specific cytotoxin produced by B. thuringiensis. In this review, we describe examination of interaction between inclusion proteins of B. thuringiensis and brush border membrane of insects using a surface plasmon resonance-based biosensor, identification and characterization of parasporin-4, the latest parasporin produced by the B. thuringiensis A1470 strain, and an effective method for preparing the parasporin-4 from inclusion bodies expressed in the recombinant Escherichia coli cells.

• Journal of the Korean Ceramic Society
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• v.19 no.3
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• pp.215-222
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• 1982

This study is to investigate the effect of a domestic pottery stone as a batch inclusion on the synthesis of porcelain bodies and their physical properties. The basic composition of porcelain bodies studied was consisted of 50wt% kaolin, 25wt% feldspar and 25wt% quartz. The inclusion of pottery stone was performed by partial substitution for either quartz or feldspar up to 25% of the total weight of batches. Sixteen porcelain bodied different in batch composition were prepared by firing them in the temperature range from 110$0^{\circ}C$ to 135$0^{\circ}C$ and their physical properties and microstructures were carefully examined. It was found that the inclusion of pottery stone could reudce the firing temperature for vitrification up to 5$0^{\circ}C$ but appreciably decreased the mechanical strength of sintered bodies. The most faborable result could obtain with partial substitution for both quartz and feldspar at same time up to 25% of the total batch weight.

• Journal of the Korean Society of Radiology
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• v.84 no.3
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• pp.776-781
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• 2023

Commonly, epidermal inclusion cysts (EICs) are benign cutaneous lesions that are lined with stratified squamous epithelium and may occur in all body parts, including the breasts. EICs in the breast (EICB) are commonly encountered clinically; it may be under-reported because of their mild and nonspecific clinical presentation. Malignant transformation of EICs is extremely rare, occurring 0.011%-0.045%. Presently, we report a rare case of squamous cell carcinoma arising from an EICB of a woman with invasive ductal carcinoma.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.9
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• pp.1276-1281
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• 2001

The feeding values of four indigenous Kenyan sorghum cultivars and the effects of polyvinylpyrrolidone (PVP) on the utilization of high tannin sorghum by broiler chicks were studied in two 3-week feeding trials. In Experiment 1, one hundred and five broiler chicks (initial average weight 97 g) were randomly assigned to each one of the seven grain-soybean meal diets. The diets consisted of maize [diet 1; no assayable tannin], white sorghum [diet 2; 0.59% catechin equivalents (CE)], cream sorghum [diet 3; 0.94% CE], light brown sorghum [diet 4; 2.71% CE] and dark brown sorghum [diet 5; 3.54% CE]. Diets 6 and 7 were included to test the possibility of overcoming the detrimental effects of sorghum tannins by adding PVP at 0.25% and 0.5% to dark brown sorghum, which resulted in dietary tannin levels of 3.46% and 3.38% CE respectively. In Experiment 2, the effects of tannin on dry matter digestibility (DMD) and nitrogen (N) retention were studied in a 3-week substitution assay in which high tannin sorghum (5% CE) was substituted for white maize at different inclusion levels. Ninety broiler chicks aged 7 days (initial average weight 102 g) were randomly assigned to each one of the six diets. The diets consisted of corn gluten meal and fishmeal as protein sources plus maize [diet 1] and high tannin sorghum at different inclusion levels [diets 2, 3, 4, 5 and 6], resulting in dietary tannin levels of 0, 1.25%, 1.66%, 2.08%, 2.5% and 3.2% CE respectively. Feed intake, feed efficiency and body weight gain were measured weekly. In Experiment 2, tannin absorption, DMD and N retention were measured on days 19, 20 and 21. The results of Experiment 1 showed that feed intake, feed efficiency and body weight gain were all affected by treatment (p<0.05). Diets 1, 2 and 3 gave similar body weight gains and all were better than diets 4 and 5 (i.e. 504, 517, 473 g, vs. 256, 267 g). Similarly, feed efficiencies were higher (p<0.05) for diets 1, 2 and 3 compared to diets 4 and 5 (0.4, 0.42, 0.39 vs. 0.21, 0.23). When 0.25% PVP was added to the dark brown sorghum (diet 6) there was no significant improvement in chick performance (p>0.05). However, addition of 0.5% PVP (diet 7) resulted in significant improvement (p<0.05) in body weight gain compared to the untreated dark brown sorghum. Overall, PVP did not completely overcome the deleterious effects of tannins. The results of Experiment 2 indicate that sorghum inclusion level and subsequent tannin level had no effect on feed intake, feed efficiency, weight gain, DMD and N retention. The above results suggest that tannin level should be limited to below 2.71% CE in broiler chick diets containing 20% CP and 0.4% methionine. However, in diets with 23% CP and 0.8% methionine tannin level of up to 3.2% will not affect performance. Consequently high tannin sorghum (5% CE) can be used to substitute for white maize by up to 100% in broiler chick diets.

• The Korean Journal of Zoology
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• v.31 no.1
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• pp.62-70
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• 1988

The distribution of respiratory chain complexes in beef heart and human muscle mitochondria has been explored by immunoeledron microscopy with antibodies made against beef heart mltochondriai proteins in conjundion with protein A cofloidai gold (l2nm particles). The antibodies used were made against NADH-conezyme Q reductase(complex I), ubiquinol-cytochrome-c-oxldoreductase (complex III) and cytochrome-c-oxidase(complex IV). Labeling of bed heart tissue with any of these antihodies gave gold particles randomly distributed along the mitochondrial inner membrane. The labeling of muscle tIssue mitochondria from a patient with a mitochondrial myopathy localized by biochemical analysis to complex III was quantitated and compared with the labeling of human control muscle tissue mitochondria. Four kinds of morphological changes in the mitochondrial fine strudure in the myopathy patient tissue have been found; paracrystalline inclusions consistIng of densely packed multi- lamellar structures, globular crystalline inclusions with high electron density, multilamellar strudure inclusion body(compadly and irregularly arranged concentric whirl shaped cristae)and golbular cyrstalilne inclusions located in the center of the whirl shaped cristae. Compex I and cytochrome-c-oxldase antihodies reacted to the same level in the mitochondria containing the crystalline inclusions and control mitochondria. Antibodies to complex III reacted very poorly to the mitochondria containing the crystalline Inclusions but strongly to control mitchondria. The globular crystalline inclusions in the mitochondria are not reacted antibodies to respiratory chain complexes.

• Korean Chemical Engineering Research
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• v.43 no.2
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• pp.187-201
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• 2005

Bioprocessing technologies utilizing 'biorecognition' between a solid matrix and a protein is being widely experimented as a means to replacing the conventional, solution-based technology. Frequently the matrices are chromatographic resins with specific functional groups exposed outside. Since the reactions of and interactions with the proteins occur as they are attached to the solid matrix, this 'solid-phase' processing has distinct advantages over the solution-phase technology. Solid-phase refolding of inclusion body proteins uses ion exchange resins to adsorb denaturant-dissolved inclusion body. As the denaturant is slowly removed from the micromoiety around the protein, it is refolded into a native, three-dimensional structure. Once the refolding is complete, the folded protein can be eluted by a conventional elution technique such as the salt-gradient. This concept was successfully extended to 'EBA (expanded bed adsorption)-mediated refolding,' in which the denaturant-dissolved inclusion body in whole cell homogenate is adsorbed to a Streamline resin while cell debris and other impurity proteins are removed by the EBA action. The adsorbed protein follows the same refolding steps. This solid-phase refolding process shows the potential to improve the refolding yield, reduce the number of processing steps and the processing volume and time, and thus improve the overall process economics significantly. In this paper, the experimental results of the solid-phase refolding technology applied to several biopharmaceutical proteins of various types are presented.