• Animal cells and systems
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• v.11 no.2
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• pp.205-213
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• 2007

Nek6 belongs to NIMA1 (never in mitosis, gene A) related kinase, which was originally identified in Aspergillus nidulans as a serine/threonine kinase critical for cell cycle progression. We noticed that the putative SUMOylation site is localized on the $K^{252}$ residue in $^{251}FKsD^{254}$ of Nek6, based on the consensus sequence ${\Phi}KxE$; where ${\Phi}$ represents L, I, V or F and x is any amino acid. We observed that the Nek6 SUMO mutant (K252R) has decreased protein kinase activity, nuclear speckle localization and protein stability, compared with that of the Nek6 wild type. However, the Nek6 SUMO mutant increased the cell survival rate of COS-1 cells as determined by FACS analysis. Therefore, our data suggest that SUMOylation on the $K^{252}$ residue of Nek6 is required for its normal functions, such as proper nuclear localization, kinase activity and protein stability, to control cell cycle.

• Genomics & Informatics
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• v.6 no.1
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• pp.44-49
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• 2008

Protein kinase C (PKC) is a family of kinases involved in the transduction of cellular signals that promote lipid hydrolysis. PKC plays a pivotal role in mediating cellular responses to extracellular stimuli involved in proliferation, differentiation and apoptosis. Comparative analysis of the PKC-${\alpha},{\beta},{\varepsilon}$ isozymes of 200 recently sequenced microbial genomes was carried out using variety of bioinformatics tools. Diversity and evolution of PKC was determined by sequence alignment. The ser/thr protein kinases of Streptomyces coelicolor A3 (2), is the only bacteria to show sequence alignment score greater than 30% with all the three PKC isotypes in the sequence alignment. S.coelicolor is the subject of our interest because it is notable for the production of pharmaceutically useful compounds including anti-tumor agents, immunosupressants and over two-thirds of all natural antibiotics currently available. The comparative analysis of three human isotypes of PKC and Serine/threonine protein kinase of S.coelicolor was carried out and possible mechanism of action of PKC was derived. Our analysis indicates that Serine/ threonine protein kinase from S. coelicolor can be a good candidate for potent anti-tumor agent. The presence of three representative isotypes of the PKC super family in this organism helps us to understand the mechanism of PKC from evolutionary perspective.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.4
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• pp.241-243
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• 1979

Coral damselfish (demoiselle), Chromis notatus, has been one of the most tasty sea foods in Jeju-Do, Korea, The free amino acids in tile extracts of Chromis notatus were analysed by amino acid autoanalyser. In the extracts, taurine, lysine, glycine and alanine were abundant, holding $30.3\%,\;22.7\%,\;16.0\%\;,\;11.5\%$ of total amino acid content, respectively and followed threonine, glutamic acid and serine, in order. While methionine, histidine, leucine, isoleucine, valine were poor and aspartic acid and proline were trace in content.

• Korean Journal of Food Science and Technology
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• v.21 no.3
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• pp.404-408
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• 1989

This study was conducted to confirm amino acids from the filterate of pollen treated by purified enzyme of bee larva gut for improving pollen food. The larva gut enzyme were purified by ammonium sulfate, ethanol and Sephadex gel filtration. The filterate of pollen treated with enzyme purified by ammonium sulfate showed the highest amount of amino acids. The amount of amino acids of the filterate from which the pollen was fermented with natural contaminants is 5.5 times as much as the pollen which was not fermented. The filterate of pollen treated with enzyme of bee larva gut contained eighteen different amino acids as follows : aspartates, glutamate, serine, glycine, histidine, arginine, threonine, alanine, proline , tyrosine, valine, methionine, cysteine, isoleucine, leucine, phenylalanine, lysine and trytophane.

• Journal of Life Science
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• v.16 no.6
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• pp.955-959
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• 2006

A dynamic cycle of addition and removal of O-linked N-acetylglucosamine (O-GlcNAc) at serine and threonine residues is emerging as a key regulator of nuclear and cytoplasmic protein activity. In this work, immunocytochemistry was carried out to investigate the subcellular expression of GlcNAc kinase (NAGK, EC 2.7.1.59) that catalyzes the phosphorylation of GlcNAc to GlcNAc 6-phosphate. Immunostainings of cultured rat hippocampal neurons revealed patchy or punctate distribution of NAGK. When NAGK is doublestained with caveolin-1 or flotillin, markers for caveolae and lipid rafts, respectively, NAGK was co-localized with these markers. These results indicate that most, if not all, of the NAGK immunopunctae represent caveolae and lipid rafts, and suggest NAGK's role in these membrane microdomains.

• The Korean Journal of Zoology
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• v.33 no.3
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• pp.266-275
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• 1990

c-raf protein kinase, a kind of oncogene, is a cytopiasmic serine / threonine-specific protein and is activated by mitogenic or oncogenic signals. The strncture and functions of c-raf protein kinase are considered very similar to those of protein kinase C. Using immunocytochemical approach, the time course of singal transduction of c-raf protein kinase in EC-4 cell was examined with 12-0-tetradecanoylphorbol-13-acetate (TPA) as tumor promotor and plateletderived growth factor (PDGF) as mitogenic factor. Immunoreactive c-raf was initially bound to the perinuclear membrane and then moved into the nucleus. The effect of the long-term treatment with TPA or PDGF was taken place down regulation at different time point. These results indicate that TPA and PDGF give rise to the translocation of c-raf protein kinase through the two different pathways.

• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.496-499
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• 1996

In order to develop the functional diet food, characteristics of chitosan and silk fibroin composite was designed. Chitosan extracted from a prawn and silk fibroin was prepared from silkworm. The silk fibroin was dissolved rapidly in the 8M LiBr at a temperature of more than 4$0^{\circ}C$. Amino acid composition of fibroin composite revealed the same pattern that of native silk fibroin and regenerated silk fibroin. Predominant amino acid of chitosan-fibroin composite contained glycine, alanine, serine, tyrosine, threonine, and glutamic acid in order. According to the basis on the infrared spectrum, chitosan-silk fibroin composite is not distinguished differents composite ratio of chitosan and silk fibroin.

• The Korean Journal of Zoology
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• v.33 no.2
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• pp.166-174
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• 1990

Gallena mellonella L. was parasitized by the pupal parasitoid, Brachymerica lasus Walker in the laboratory. Haemolymph total protein and carbohydrate concentrations from the hosts parasitized by B. lasus decreased within 1st day following parasitization. However, haemolymph total free amino adds, glycine, proline, arginine, isoleucine, phenylalanie, leucine, valine, glutamk acid, histidine, serine, and tyrosine increased and free amino acids decreased were threonine, aspartic acid, methionine, cysteine, alanine, and lysine.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1164-1170
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• 1996

Studies were carried out to investigate the changes of constituent components in chestnuts (Castanea crenata Sieb. et Zucc) during storage at $20^{\circ}C$ for 9 weeks and $1^{\circ}C$ for 15 weeks. Ascorbic acid content of chestnut was 4.08 mg% in oxidized form and 17.7 mg% in reduced form which was 81.3% of total ascorbic acid. The reduced form gradually decreased during storage, while the oxidized forms increased during 5 weeks at $20^{\circ}C$ and 7 weeks at $1^{\circ}C$. The major organic acids in chestnut were malic acid, citric acid and quinic acid. Citric acid significantly decreased during storage, while malic acid increased during storage at $20^{\circ}C$ and decreased at $1^{\circ}C$. Free sugars in chestnuts were identified as glucose, fructose, sucrose and maltose. Glucose and fructose decreased after 5 weeks storage at $20^{\circ}C$ followed by an increase thereafter. Sucrose and maltose also increased. The major free amino acids in the chestnut were glutamic acid, aspartic acid, arginine, alanine, proline and serine. Glutamic acid, arginine, alanine, threonine, phenylalanine, valine and lysine increased during storage at $20^{\circ}C$, while proline, serine, isoleucine. leucine and ${\gamma}-aminobutyric$ acid decreased.

• Journal of Plant Biology
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• v.39 no.1
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• pp.41-48
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• 1996

Two forms of homo serine dehydrogenase have been isolated from 8-day-old cotyledons of Canavalin lineata by a heat denaturation, ammonium sulfate fractionation, DEAE-8ephacel ion exchange and Sephacryl 8-300 gel filtration chromatographies, and Pro cion red dye, Cibacron blue dye and Resource Q column chromatographies. The molecular weights of T -form (threonine-sensitive) and K-form(threonine- insensitive) were estimated to 230 kD and 135 kD, respectively. In the presence of 10 mM threonine, the activity of T-form was inhibited with almost 70%, but that of K-form was not at all. The Km values tor homo serine of T- and Kform were 1.6 mM and 0.3 mM, respectively. The Km values for NAD of T- and K-form were 2.34 mM and 0.03 mM, respectively. And Km values for NADP of two isozymes were the same as 0.01 mM. The activities of T- and K-form were markedly stimulated up to 4.9and 2.8-fold, respectively, by 400 mM KCI. The partial purified(gel filtration) enzymes(Tform and K-form) can be reversibly converted.verted.