• Korean Journal of Food Science and Technology
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• v.12 no.2
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• pp.88-96
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• 1980

Reaction conditions in the amino-carbonyl reaction, and the effect of amino acids on the reactivity of amino-carbonyl reaction were investigated. Results obtained are as follows : 1. When the pH of the reaction mixture was increased above the isoelectric point of an amino acid, a significant increase in the color intensity was observed. 2. The color intensity increased gradually up to 1 : 1 of the molar ratio of reactants. This result was interpreted to show that sugar and free amino group combined in 1 : 1 ratio. 3. Amino-carbonyl reaction showed a significant time and temperature-dependences. The activation energy at 0.2 M glucose and 0.2 M glycine system was 37.5 Kcal/mole. 4. Among amino acids tested, glycine, lysine and $\beta$-alanine caused a significant increase in the color intensity, but acidic amino acids showed the least color intensity. The latter was interpreted to show that one of carboxyl groups of acidic amino acid has an inhibiting effect on the reactivity of the amino group. 5. The color intensity of sugars tested was in the order of xylose>arabibose>fructose>glucose>maltose>lactose.

• Archives of Pharmacal Research
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• v.20 no.5
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• pp.459-464
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• 1997

The human liver cDNA clone UDPGTh2, encoding a liver UDP-glucuronosyltransferase (UDPGT) was isolated from a .gamma. gt 11 cDNA library by hybridization to mouse transferase cDNA clone, UDPGTm1. UDPGTh2 encoded a 529 amino acid protein with an amino terminus membrane-insertion signal peptide and a carboxyl terminus membrane-spanning region. There were three potential asparagine-linked glycosylation sites at residues 67, 68, and 315. In order to obtain UDPGTh2 protein encoded from cloned human liver UDP-glucuronosyltransferase cDNA, the clone was inserted into the pSVL vector (pUDPGTh2) and expressed in COS 1 cells. The presence of a transferase with Mr-52,000 in transfected cells cultured in the presence of $[^{35}S]$ methionine was shown by immunocomplexed products with goat antimouse transferase IgG and protein A-Sepharose and analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. The expressed UDPGT was a glycoprotein as indicated by electrophoretic mobility shift in Mr-3,000-4,000 when expressed in the presence of tunicamycin. The extent of glycosylation was difficult to assess, although one could assume that glycosyl structures incorporated at the level of endoplasmic reticulum were always the core oligosaccharides. Thus, it is likely that at least two moieties inserted can account for the shift of Mr-3,000-4,000. This study demonstrates the cDNA and deduced amino acid sequence of human liver UDP-glucuronosyltransferase cDNA, UDPGTh2.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.275-275
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• 2002

Pseudomonas sp. S-47 is capable of catabolizing 4-chlorobenzoate (4CBA) as carbon and energy sources under aerobic conditions via the mesa-cleavage pathway. 4CBA-dioxygenase and 4CBA-dihydrodiol dehydrogenase (4CBA-DD) catalyzed the degradation af 4CBA to produce 4-chlorocatechol in the pathway. In this study, the xylL gene encoding 4CBA-DD was cloned from the chromosomal DNA of Pseudomonas sp. S-47 and its nucleotide sequence was analyzed. The xylL gene was found to be composed of 777 nucleotide pairs and to encode a polypeptide of 28 kDa with 258 amino acid residues. The deduced amino acid sequence of the dehydrogenase (XylL) from strain S-47 exhibited 98% and 60% homologies with these of the corresponding enzymes, Pseudomonas putida mt-2 (XyIL) and Acinetobacter calcoaceticus (BenD), respectively. However, the amino arid sequences show 30% or less homology with those of Pseudomonas putida (BnzE), Pseudomonas putida Fl (TodD), Pseudomonas pseudoalcaligenes KF707 (BphB), and Pseudomonas sp. C18 (NahB). Therefore, the 4CBA-dihydrodiol dehdrogenase of strain S-47 belongs to the group I dehydrogenase involved in the degradation of mono-aryls with a carboxyl group.

• Elastomers and Composites
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• v.56 no.4
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• pp.254-263
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• 2021

In this study, chitosan obtained after varying extents of deacetylation (i.e., 10%, 30%, and 47%) was employed to introduce antibacterial properties to chitin. The deacetylation reaction completion, wherein the amino group content of chitin was reduced, was ascertained from the FT-IR and NMR analyses. The 47%-deacetylated chitosan exhibited superior antibacterial properties against Bacillus in a disk diffusion test. To further improve these properties, chitosan derivatives were grafted by acrylic acid and acrylamide. The varying concentrations of carboxyl groups, primary amines, and -CH₂-CH₂- with increasing acrylic acid and acrylamide contents were determined by FT-IR and NMR analyses. The enhanced antibacterial properties of the chitosan derivatives, owing to the increased acrylic acid and acrylamide contents, were revealed by the disk diffusion test. In particular, the derivatives with 1.3% acrylic acid and acrylamide showed the highest antibacterial activity, the bacterial reduction rate against Staphylococcus aureus and Escherichia coli being 99.9%, as observed through the ASTM E2149 standard test.

• Applied Biological Chemistry
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• v.36 no.6
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• pp.525-532
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• 1993

To characterize the prolamines in rice cultivars, the complete coding sequences of 17 prolamine genes from the database were analyzed. According to the phylogenic analysis of the sequences, these genes could be classified into 4 groups, Group I to IV. The multiple alignment of the deduced amino acid sequences revealed that the four groups differ from one another in chain length caused by deletion of short internal amino acids or carboxyl terminal fragments. Each group was also found to have different amino acid composition with 1, 4, 10 and 30% of sulfur containing amino acids (methionine and cysteine) in Group I to IV prolamines, respectively. Also the isoelectric points of these groups showed the different values of 9.2, 8.2, 6.7 and 7.4. Finally, from the analysis of codon usage pattern of prolamine genes, the codon usage for arginine, serine, threonine, isoleucine, asparagine, aspartic acid, glutamic acid and cysteine were higly biased. In the analysis of the codon usage pattern, the relation of the fraction of G/C ending codons to effective codon numbers suggests the different translational efficiency in the expression of the prolamine multigenes.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.1
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• pp.44-52
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• 1996

Humic substances of 17 organic fertilizers available on the market were the objects of study. The list of ingredients for formulation of them comprised fish meal. bone meal, oil-cakes, brewer's grains, peat, sawdust, wood bark, zeolite, soil conditioner, live-stock droppings, amino acid fermentation byproduct, chaff, limestone and others. Humic and fulvic acids were isolated from those substances and given chemical and spectroscopic analyses. Nutritional values of the organic fertilizers showed big diversity. Humification of organic matter was incomplete for some of the fertilizers as indicated by a high C/N ratio. Extractable humic acid percentage was higher, in general, than that of fulvic acid. Also the relative content of humin increased with advanced humification. Total acidity was closely related to phenolic hydroxyl groups. Relationships between carboxyl and hydroxyl groups. and carboxyl and alcoholic hydroxyl groups were very significant. Ultraviolet and visible light absorption spectra of humic and fulvic acids were substantially similar. The types of humic acids were B. P, and Rp. Two humic acids of the 17 samples belonged to B type. 3 to P type and all the rest to Rp type.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.4
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• pp.1037-1049
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• 2003

Numerous lines of evidence indicate that some of the neurotoxicity associated with Alzheimer's disease (AD) is due to proteolytic fragments of the amyloid precursor protein (APP). Most research has focused on the amyloid 6 (M). However, the possible role of other cleaved products of APP is less clear. Lately It has been reported that a recombinant carboxy-terminal 105 amino acid fragment (CT105) of APP induced strong nonselective inward currents in Xenopus oocyte. In a brain with Alzheimer's disease (AD), to investigate the roles of carboxyl-terminal fragment (CT105) of amyloid precursor protein (APP) in apoptosis processes possibly linked to neurodegeneration associated with AD, we examined the effects of the CT of APP with 105 amino acid residues (CT105) on the alteration of apoptosis triggers in neubroblastoma cells. We have investigated whether Radix Polygalae and Rhizoma Acori Graminei mixture extract (RP+RAG) inhibits CT105-induced apoptosis of neuroblastoma cells. We found that RP+RAG inhibits CT105-induced apoptosis in SK-N-SH cells. Treatment of the cells with RP+RAG inhibited CT105-induced DNA fragmentation and Tunel assay of nuclear chromatin and inhibited the caspase-3 expression in SK-N-SH cells. As the result of this study, In RP+RAG group, the apoptosis in the nervous system is inhibited, the repair against the degerneration of neuroblastoma cells by CT105 expression is promoted. These results indicate that RP+RAG possess strong inhibitory effect of apoptosis in the nervous system and repair effect against the degeneration of neuroblastoma cells by CT105 expression

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.156-157
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• 1998

Taurine is synthesized in the body or uptaken from dietary and is distributed in the various organs. It differs from other amino acids by virtue of the fact that a sulfonic acid group replaces the carboxyl group of what would be ${\beta}$-alanine. In order to function within the cell it must be transported into the cells by taurine transporter that is spanned 12 transmembrane domains. The human taurine transporter has long cytoplasmic carboxy and amino termini that may function as regulatory attachment sites for other proteins. Six potential protein kinase C(PKC) phosphorylation sites have been reported in human taurine transporter.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1978.10a
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• pp.206.4-206
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• 1978

By utilizillg whole cell enzyme of the Xantho-monas citri IFO 3835, cephalexin is synthesized directly from 7-amino-deacetoxy cephalosporanic acid (7-ADCA) and phenyl glycine methyl ester (PGM). To date, cephalexin has been manufactu-red by chemical process involving fairly large number of steps to protect the amino group of phenly glycine and carboxyl group of 7-ADCA. However, the enzymatic process involves only a single step with 85％ conversion in 90 minutes. The fermentation variables studied indicate that oxygen transfer is limiting step in the enzyme production. Optimum conditions for enzymatic reaction were 37 C, pH 6.0, and the optimum substrate molar ratio of PGM to 7-ADCA was 2. Other variables that are related to the biochemical properties of whole cell enzyme temperature stability, pH stability, kinetic constants, reusing effect, enzyme loading effect were also evaluated.

• The Korean Journal of Physiology
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• v.12 no.1_2
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• pp.15-23
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• 1978

The action of ascorbic acid on the sodium Plus potassium activated ATPase activity in the rabbit red cell membrane has been investigated and the experiments were also designed to determine the mechanism of action if ascorbic acid on the ATPase activity The following results were observed. 1. The activity of the NaK ATPase from red cell membrane is stimulated by ascorbic acid and the concentration of ascorbic acid for maximal activity is about 8 mM. 2. The activating effect of ascorbic acid on the ATPase activaty, with a given concentration of sodium in the medium, is increased by raisins the potassium concentration but activity ratio is decreased. 3. The activating effect of ascorbic acid on the ATPase activity, with a given concentration of potassium in the medium, is increased by raising the sodium concentration but activity ratio is decreased. 4. The action of ascorbic acid on the ATPase activity is stimulated by calcium ions and activity ratio is increased by raising the calcium concentration. 5. The activating effect of ascorbic acid on the ATPase activity was not related to the sulfhydryl group of cysteine or the hydroxyl group of threonine. 6. The activating effect of ascorbic acid on the ATPase activity is due to amino group and carboxyl group of the enzyme of NaK ATPase.