• Journal of Microbiology
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• 제34권4호
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• pp.384-386
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• 1996

Application of polyacrylamide gel (PAG) instead of agar to solid cultures of Streptomyces spp. was studied. The improved media were prepared by 1) gelling 20 ml of 5% acrylamide in a glass petri dish at room temperature, 2) washing by running water for more than 8 hr to remove residual reaction reagents, 3) drying at 5$0^{\circ}C$ for 12 hr to make a gel film, 4) autoclaving at 121$^{\circ}C$ for 15 min, and 5) swelling gel for about 4 hr by adding sterile liquid medium. In PAG media there were no differences from the observation of morphological characteristics showing during the cellular differentiation on agar media, whereas the ability to utilize carbohydrates differed somewhat from agar media. Agar media thus were little favorable for biochemical tests which the growth was determined depending on the formation of colony, but washed PAG was superior to serve as a solidifying agent.

• Journal of Microbiology and Biotechnology
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• 제12권4호
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• pp.598-602
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• 2002

Damage to cells exposed to radiation is primarily attributed to direct effects on the structure of cellular DNA. Radiation-induced damage of pBluescript SK plasmid DNA and Escherichia coli $DH5\alpha$ were examined in the presence of various branched oligosaccharides, polysaccharides, and/or 8-MOP (8-methoxypsoralen). Branched oligosaccharides efficiently protected DNA and cells exposed to ultrasoft X-ray and UV irradiation. In the presence of 0.2% (w/v) branched oligosaccharides and polysaccharides, DNA can be protected from damage due to W and ultrasoft X-ray by a factor of 1.3-2.1 fo1d and 3.2-8.3 fold, respectively. The protective effect of cells exposed to UV or ultrasoft X-ray was also observed by branched oligosaccharides. The combination of MOP, a photoreagent, with carbohydrates increased the protective effects for DNA and cells, compared with that of a single use of MOP or carbohydrate alone.

• 미생물학회지
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• 제6권2호
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• pp.41-53
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• 1968

Studies on the carbohydrate metabolism of yeast as influenced by gamma-irradiation from cobalt-60 have been carried, then the mechanisms of radiation effect on respiration and fermentation were discussed under considerations of permeable changes of irradiated cell membrane. The cells of baker's yeast (Saccharomyces cerevisiae) which had been gamma-irradiated of 240 k.r. doses for an hour, then were put into aerobic oxidation and anaerobic fermentation without substrate. Total and fractionated carbohydrates of irradiated yeast cells were determined by calorimetric method with anthrone and orcinol reagents, the amounts of total carbohydrate, trehalose, RNA-ribose, PCA-soluble glycogen, alkali-soluble glycogen, acetic acid-soluble glycogen, mannan and glucan were determined according to the course of aerobic oxidation and anaerobic fermentation. It is found that the carbohydrates of irradiated cells leak out and amount of the losses teaches eleven times more than that of control, the volume of losses are seems to be replaced by water, it can be suggested the damage of gamma-irradiation occurs in the site of passive transport of cell membrane. The endogeneous aerobic respiration of irradiated cells are increased much more than control, the synthesis of reserve glycogen, glucan and RNA-ribose promoted much more than control. The anaerobic fermentation of irradiated cells are also increased than that of control, but the breakdown of carbohydrate is less than endogeneous respiration of irradiated cells. The synthetic rate is also less than that of aerobic oxidation. In irradiated yeast cells, trehalose is revealed to be primary substrate for endogeneous carbohydrate metabolism, so it is proved that the enzymic patterns are not changed but the activities of enzymes relating endogeneous respiration and autofermentation is activated. It is to be considerable to distiguish endogeneous respiration and autofermentation from exogeneous respiration and fermentation on irradiation, for membrane permeability changes and loses out carbohydrate by ionizing radiation.

• 미생물학회지
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• 제19권2호
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• pp.63-77
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• 1981

The growth rate of yeast population (Saccharomyces uvarum) cultivated in the Knopp's modified medium (plus various carbon sources) appeared the highest value when the Knopp's minimal medium was treated to 1.5% with disaccharide such as maltose and sucrose. Also the treatment of lactose and raffinose resulted in polulation growth as to the population size in case of maltose and sucrose. However, the gorwth of yeast was not occurred at all when a polysaccharide, such as inulin, was added as carbon source. The growth from of yeast population in Knopp's modified medium are characterized by the fact that log phase continued 100hrs after inoculation and that stationary state phase appeared in general 250hrs after inoculation. Applying the various carbon sources to respiration substrate for yeast cell, the respiration rate of yeast showed the highest value in treatment of maltose and followed in order of raffinose, lactose, glucose, and sucrose. Determined the amount of poly-phosphate and turn over pathway of poly-phosphate according to culture phase of yeast, it is revealed that the yeast synthesized 3 types of poly phosphate (poly-P A,B, and C) and postulated that turn over pathway of poly-phosphate as follows ; Inorganic phosphate is converted into each kind of polyphosphates, and then one part of poly-P-C is converted into poly-P-B, the rest poly-p-C and poly-P-B are converted into poly-P-A. The synthesized poly-phosphate is considered to have a role as energy pool utilizing to synthesis of cellular organic materials. Of the 13 carbon sources used in this experiment, the useful carbon sources for biosynthesis of poly-phosphate and cellular organic materials are confirmed as disaccharide (maltose and sucrose) as well as glucose. Protein synthesis in yeast cell showed the two peaks on 6th and 8th day after inoculation ; nucleic acid on 2nd day (48hrs), carbohydrates on 2nd day (48hrs), and phospholipid on 2nd and 8th day after inoculation, respectively.

• 생약학회지
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• 제42권3호
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• pp.246-252
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• 2011

Korean mistletoe Lectin (KML-C) is composed of A and B sub-chain. B chain binds to carbohydrates on cell surface and A chain hinders translation and induces an apoptosis as a RIP (ribosome inactivating protein). KML-C has very strong biological activities, it has seriously limits to use as a cancer therapy or adjuvant because of its toxicity to normal cells. This study is therefore conducted to see if B chain of KML-C might have immunological activity, especially adjuvant activities with less toxicity. We isolated B chain from KML-C using the lactose affinity chromatography, and examined their immunoadjuvant activity. The isolated B-chain did not show any cytotoxicity against tumor cell, RAW264.7, and P388D1 while KML-C had a very strong toxicity. This non-toxic effect was observed also by in-vivo study. Both humoral and cellular immunities were observed ; the antibody titer was increased when the mice were immunized with B-chain used as adjuvant like Freund's adjuvant, indicating that B chain of mistletoe lectin alone might be used for adjuvant; it also increased DTH in cellular immunity. These results suggest that B-chain of KML-C might be used for adjuvant used for the production of antibody or vaccine with less toxicity.

• Journal of Periodontal and Implant Science
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• 제30권3호
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• pp.599-610
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• 2000

Gingival fibroblasts are embedded in an extracellular matrix. The matrixs have influence on the development, polarity, and behavior of nearby cells. The major component of periodontal extracellular matrix is a glycosaminoglycan. The glycosaminoglycan are large carbohydrates that are composed of repeating disaccharide units and exist in three main form: dermatan sulfate, chondrotitin sulfate, heparan sulfate. The purpose of present study is to examine the biologic effects of glycosaminoglycan on human gingival fibroblast. Human gingival fibroblasts were supplemented with each glycosaminoglycan, and cellular attachment and proliferation was determined by MTT assay. Dermatan sulfate and chondroitin sulfate did not stimulate the attachment and proliferation of human gingival fibroblasts, but heparan sulfate increased the proliferation and attachment in a time- and dose dependent manner. These results indicated that heparan sulfate seems to have a high potential for gingival regeneration and root surface attachment.

• 생명과학회지
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• 제8권4호
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• pp.387-394
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• 1998

A thermophilic bacterium (strain DG0303) producing a thermostable $\alpha$-glucosidase was isolated from manure and identified as Bacillus sp. Strain DG0303 produced high level of $\alpha$-glucosidase compared with other thermophilic Bacillus strains. The cellular protein patterns were also compared with other Bacillus strains by sodium dodecyl sulfatepolyacrylamide gel electrophoresis(SDS-PAGE). On the basis of 16S rDNA analysis the Bacillus sp. DG0303 was found to be a member of Bacillus rDNA group 5. The optimum temperature for growth was 65$\circ$C and no growth was obtained at 40$\circ$C or 75$\circ$C. The optimum pH for growth was 5.5 to 8.5. $\alpha$-glucosidase activity was produced during growth and most activity was detected in the culture supernatant. The $\alpha$-glucosidase production was constitutive in the absence of carbohydrates. High level of enzyme activity was detected when the culture was grown on medium containing starch. Addition of glucose resulted in the repression of the $\alpha$-glucosidase production. The optimum pH and tempoerature for enzyme activity were pH 5.0 and 65$\circ$C, respectively. When analyzed by zymogram, the culture supernatant showed a single $\alpha$-glucosidase band with a molecular weight of approximately 60,000.

• Animal Bioscience
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• 제36권2_spc호
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• pp.350-363
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• 2023

Beef quality is characterized by marbling (marbling degree and marbling fineness), physiochemical (shear force, meat color, fat color, texture, and maturity), and sensory (tenderness, flavor, juiciness, taste, odor, and appearance) traits. This paper summarizes and addresses beef-quality characteristics and the beef-grading systems in Korea, Japan, the USA, and Australia. This paper summarizes recent research progresses on the genetic and nutritional factors that affect beef quality. Intramuscular (i.m.) adipose tissue deposition or marbling is a major determinant of beef quality. This paper addresses the mechanisms of i.m. adipose tissue deposition focused on adipogenesis and lipogenesis. We also address selected signaling pathways associated with i.m. adipose tissue deposition. Nutrients contribute to the cellular response and phenotypes through gene expression and metabolism. This paper addresses control of gene expression through several nutrients (carbohydrates, fat/fatty acids, vitamins, etc.) for i.m. adipose tissue deposition. Several transcription factors responsible for gene expression via nutrients are addressed. We introduce the concept of genome-based precision feeding in Korean cattle.

• 한국미생물·생명공학회지
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• 제22권5호
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• pp.467-476
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• 1994

Lactobacillus casei HY 2782, prophage cured strain was characterized to be stable as much as L casei YIT 9018, parent strain. By southern hybridization, it was confirmed that the temperate phage was incorporated in chromosomal DNA of L. casei YIT 9018 as a prophage. It was also proved that the prophage was cured from chromosomal DNA of L casei HY 2782. The growth rate, lactic acid producing ability, carbohydrates fermentation, and enzymatic activity of L. casei HY 2782 were found to be similar to those of L. casei YIT 9018. When L casei HY 2782 was used as a host, the multiplicity of infection (M.O.I.) of the temperate phage for L. casei HY 2782 was 1.0~5.0. Restriction enzyme analysis of pLC90 plasmid from L. casei HY 2782 was shown that the size was an approximately 68.22 kb. The plasmid profiles, genomic DNA patterns, and cellular fatty acids composition of L. casei HY 2782 were similar to those of L casei YIT 9018. And the major fatty acids composition of these strains were C$_{14;0}$,C$_{16;1}$, C$_{16;0}$, C$_{18;1}$ and C$_{19;cyclo-}$ 10 sets of arbitrary primer in the PCR were screened to find differentiation against two strains of L. casei. Among them, b$_{5}-1/17-1 primer was produced an approximately 1.3 kb DNA band of only L casei YIT 9018. And b$_{5}-2/17-2 primer was produced an approximately 1.0 kb DNA band of only L casei HY 2782.

• Molecules and Cells
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• 제39권6호
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• pp.495-500
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• 2016

We have solved the crystal structure of a predicted fructose-specific enzyme $IIB^{fruc}$ from Escherichia coli ($EcEIIB^{fruc}$) involved in the phosphoenolpyruvate-carbohydrate phosphotransferase system transferring carbohydrates across the cytoplasmic membrane. $EcEIIB^{fruc}$ belongs to a sequence family with more than 5,000 sequence homologues with 25-99% amino-acid sequence identity. It reveals a conventional Rossmann-like ${\alpha}-{\beta}-{\alpha}$ sandwich fold with a unique ${\beta}$-sheet topology. Its C-terminus is longer than its closest relatives and forms an additional ${\beta}$-strand whereas the shorter C-terminus is random coil in the relatives. Interestingly, its core structure is similar to that of enzyme $IIB^{cellobiose}$ from E. coli ($EcIIB^{cel}$) transferring a phosphate moiety. In the active site of the closest $EcEIIB^{fruc}$ homologues, a unique motif CXXGXAHT comprising a P-loop like architecture including a histidine residue is found. The conserved cysteine on this loop may be deprotonated to act as a nucleophile similar to that of $EcIIB^{cel}$. The conserved histidine residue is presumed to bind the negatively charged phosphate. Therefore, we propose that the catalytic mechanism of $EcEIIB^{fruc}$ is similar to that of $EcIIB^{cel}$ transferring phosphoryl moiety to a specific carbohydrate.