• BMB Reports
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• v.43 no.2
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• pp.103-109
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• 2010

Modification of proteins by the reversible covalent addition of the small ubiquitin like modifier (SUMO) protein has important consequences affecting target protein stability, sub-cellular localization, and protein-protein interactions. SUMOylation involves a cascade of enzymatic reactions, which resembles the process of ubiquitination. In this study, we characterized the SUMOylation system from an important crop plant, rice, and show that it responds to cold, salt and ABA stress conditions on a protein level via the accumulation of SUMOylated proteins. We also characterized the transcriptional regulation of individual SUMOylation cascade components during stress and development. During stress conditions, majority of the SUMO cascade components are transcriptionally down regulated. SUMO conjugate proteins and SUMO cascade component transcripts accumulated differentially in various tissues during plant development with highest levels in reproductive tissues. Taken together, these data suggest a role for SUMOylation in rice development and stress responses.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2001.05a
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• pp.147-155
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• 2001

Nasucon lamp and Russian ones, which are coated with some special materials on the glass bulb, gave good clinical results for a cancer therapy. They are experimentally studied with Automatic Bioelectric Response Recorder on the six placements of the electrodes (two feet, two hands and two foreheads). They reduced the current rather than the control (natural) state. However infrared lamp and Chinese God light did not reduced the value current. Hemoglobin in blood. Brown gas, Ti$_3$SiC$_2$ and Nasucon have planar crystallizing $\pi$-bonding bonding layer and covalent bonding one in sequence commonly and thus the alternating magnetic fields are protected. Nasucon lamp and Russian ones utilized electric bulbs in order to generate alternating magnetic fields and to produce absorbing force.

• Textile Coloration and Finishing
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• v.5 no.3
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• pp.173-181
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• 1993

Dyeing cotton fabric with direct dye (C. I. Direct Blue 15) by redox sytem of ammonium persulfate as an oxidant and glucose as reductant was studied. It was found that covalent bond between dye and cellulose molecule can be formed by free radical produced by the redox system in the dye bath, which enhanced significantly the color strength. The retained color strength after DMF extraction was much better in the presence than in the absence of the redox sytem. The optimum dyeing condition was 0.028 mol/$\ell$(APS/Glucose each) of redox concentration, 65$^{\circle}C$ of dyeing temperature and 60min of dyeing time. The color variation on the dyed sample had not been observed as a result of fixed ${\lambda}_max$.

• Macromolecular Research
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• v.17 no.4
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• pp.227-231
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• 2009

New polyelectrolytes derived from poly(amide-sulfone)s and 1,5-dibromopentane were simultaneously fabricated on the electrode by the crosslinking reaction. The substrate was pretreated with a bromoalkyl-containing, silane-coupling agent to anchor the humidity-sensitive membrane to the substrate through the covalent bond. When the resistance dependence on the relative humidity of the crosslinked poly(amide-sulfone)s was measured, the resistance varied by three orders of magnitude between 20%RH and 90%RH, which was the required RH range for a humidity sensor operating at ambient humidity. Their water durability, long-term stabilities under various environments, hysteresis and response and recovery times were measured and evaluated as a humidity-sensing membrane.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.502-505
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• 2007

PMMA has been extensively adopted in Nano Imprint Lithography(NIL). PMMA nano-structures experience severe mechanical load and deformation during NIL process, and understanding its mechanical behavior is very important in designing and optimizing NIL process. One of the most promising techniques for characterizing the mechanical behavior of nano structures is nano pillar compression test. In this study, the mechanical behaviors of PMMA pillars during compression test are analyzed using Molecular Dynamics. Two methods for simulation of PMMA nano pillars are proposed. The stress-strain relationship of nano-scale PMMA structure is obtained based on CVFF(Covalent Valence Force Fields) potential and the dependency of the applied strain rate on the stress-strain relationship is analyzed. The obtained stress-strain relationships can be useful in simulating nano-scale PMMA structures using Finite Element Method(FEM) and understanding the experimental results obtained by compression test of PMMA nano pillars.

• Journal of Crop Science and Biotechnology
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• v.11 no.1
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• pp.1-6
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• 2008

The covalent conjugation of SUMO(Small Ubiquitin-related MOdifier) protein to its substrates regulates numerous cellular processes, including protein stability and activity in eukaryotes as well as in plants. In this present review, we summarize biochemical aspects of SUMO conjugation and deconjugation and the functions of SUMO and sumoylation-related proteins in Arabidopsis and other plants. In particular, we provide an overview of the roles of the SUMO in widely different biological processes including the ABA response, floral induction, pathogen defense, abiotic stresses and hormone signaling. Furthermore, we explore the possible roles of SUMO in embryo and seed development.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.506-508
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• 1986

Metabolic activity of inorganic nitrogenous compounds affects not only microbial growth but also metabolite production in fermentation technology. We have worked on the enzymes participating in ammonia assimulation of some fermentation bacteria. This paper summarizes the results on glutamine synthetase and its application in practical field. Glutamine synthetase (L-glutamate:ammonia ligase, EC. 6.3.1.2) catalyzes the formation of glutamine from glutamate and ammonia at the expense of cleavage of ATP and inorganic phosphate. The enzyme plays a dual role in nitrogen metabolism in bacteria; it is a key enzyme not only in the biosynthesis of various compounds through glutamine but also in the regulation of synthesis of some enzymes involved in the metabolism of nitrogenous compounds. The detailed works with the Eschericia coli and other enterobacterial enzymes revealed that glutamine synthetase is controlled by the following complex of mechanisms: (a) feedback inhibition by end products, (b) repression and derepression of enzyme synthesis, (c) modulation of enzyme activity in response to divalent cation and (d) covalent modification of enzyme protein by adenylylation and its cascade control. Comparative studies have also been made on the enzymes from other organisms.

• Current Photovoltaic Research
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• v.5 no.2
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• pp.43-46
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• 2017

Large absorption band shift has been observed for the azo-dye (disperse red-13, DR-13) attached on the surface of silica spheres. Urethane linkage has been utilized to form covalent bond between azo-dye (-OH) and 3-isocyanatopropyltriethoxysilane (ICPTES, -N=C=O). The synthesized ICPTES-DR-13 (ICPDR) molecules were attached to the silica spheres by the hydrolysis and condensation reaction. Although the absorption peak of DR-13 in methanol is at 510 nm, the absorption peak of the ICPDR-silica spheres shifts to 788 nm. The large absorption peak shift is due to the formation of intramolecular charge-transfer band with large aggregated ICPDR.

• Food Science and Biotechnology
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• v.18 no.4
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• pp.1027-1029
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• 2009

The aim of this research was to study the structural and rheological properties of gels formed by ferulated maize bran arabinoxylans (MBAX) at different concentrations. MBAX was cross-linked by a laccase leading to the formation of dimers and trimers of ferulic acid (di-FA, tri-FA) as covalent cross-link. An increase in MBAX gels elasticity (from 11 to 20 Pa) as well as lower mesh size (from 80 to 48 nm) were obtained by augmenting the MBAX concentration from 2.5 to 3.5%(w/v), respectively, but no increase in di-FA and tri-FA content was obtained (0.03 and 0.014 ${\mu}$g/mg MBAX, respectively).

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.9
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• pp.1127-1136
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• 2010

Yogurt gels are a type of soft solid, and these networks are relatively dynamic systems that are prone to structural rearrangements. The physical properties of yogurt gels can be qualitatively explained using a model for casein interactions that emphasizes a balance between attractive (e.g., hydrophobic attractions, casein cross-links contributed by calcium phosphate nanoclusters and covalent disulfide cross-links between caseins and denatured whey proteins) and repulsive (e.g., electrostatic or charge repulsions, mostly negative at the start of fermentation) forces. Various methods are discussed to investigate the physical and structural attributes of yogurts. Various processing variables are discussed which influence the textural properties of yogurts, such as total solids content, heat treatment, and incubation temperatures. A better understanding of factors contributing to the physical and structural attributes may allow manufacturers to improve the quality of yogurt.