• 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.

• BMB Reports
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• v.43 no.6
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• pp.419-426
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• 2010

Aeromonas hydrophila is a bacterial pathogen that infects a large number of eukaryotes, including humans. The UDP-galactose 4'-epimerase (GalE) catalyzes interconversion of UDP-galactose to UDP-glucose and plays a key role in lipopolysaccharide biosynthesis. This makes it an important virulence determinant, and therefore a potential drug target. Our earlier studies revealed that unlike other GalEs, GalE of A. hydrophila exists as a monomer. This uniqueness necessitated elucidation of its structure and active site. Chemical modification of the 6xHis-rGalE demonstrated the role of histidine residue in catalysis and that it did not constitute the substrate binding pocket. Loss of the 6xHis-rGalE activity and coenzyme fluorescence with thiol modifying reagents established the role of two distinct vicinal thiols in catalysis. Chemical modification studies revealed arginine to be essential for catalysis. Site-directed mutagenesis indicated Tyr149 and Lys153 to be involved in catalysis. Use of glycerol as a cosolvent enhanced the GalE thermostability significantly.

• Journal of the Korean institute of surface engineering
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• v.50 no.2
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• pp.108-113
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• 2017

We investigated the effect of graphite electrode geometry and combination on nanocarbon material synthesis using underwater discharge plasma(UDP). The UDP system consists of two graphite electrodes and beaker filled with de-ionized water. A high voltage of 15 kV with a frequency of 25 kHz is applied to produce UDP using an alternating-current power source. The UDP system with conical electrodes produced the largest amount of products due to the concentration of electrical fields between electrodes. In addition, hollow-shaped stationary electrode and conical-shaped moving electrode stores discharge-induced bubbles and maintains longer reaction time. We found from Raman spectroscopy and electron microscopy that high quality carbon nanomaterials including carbon nanotubes are synthesized by the UDP system.

• Journal of Korea Society of Industrial Information Systems
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• v.12 no.2
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• pp.30-36
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• 2007

The UPnP uses the same standard protocol as SSDP and UDP based on standard internet and technology like the TCP/IP, and is independent of other physical networking product. But the structure of the UPnP has the of vulnerability to the security countermeasure for home-networking technology since it is operated on the same protocol as the SSDP and UDP. In this paper, we analyze and report against the DoS attack, where the worm virus, using the vulnerability to the UPnP, eliminates the attack of all equipments that are based on networking and eliminates the information belonging to the equipments of the home-networking or transmits the massive data.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.7
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• pp.974-978
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• 2001

The effect of three varying ratios (high, medium and low) of Rumen Degradable Protein (RDP) to Undegradable Dietary Protein (UDP) of 37:63, 52:48 and 70:30 in iso-nitrogenous and iso-caloric concentrate mixtures on rumen fermentation profile was studied using rumen fistulated Jersey crossbred cows. Rumen pH and ammonia nitrogen concentration were found to be lower with a concentrate mixture containing a higher UDP level of 63.38% when compared with those having medium and low UDP levels of 47.55 and 29.75%, respectively, at all post feeding intervals. Total volatile fatty acid concentration as well as concentrations of individual fatty acids viz., acetate, propionate and butyrate were also found higher in animals fed concentrate mixture with the highest UDP level.

• Journal of Life Science
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• v.2 no.4
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• pp.232-239
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• 1992

UDP_GlcNAc is metabolized to form vegetative cell wall, cortical peptidoglycans, and outermost layer consisting of galactosamine-6-phosphate ploysaccharide in life cycle of Bacillus megaterium. To obtain a better understanding of the UDP-GlcNAc regulation, we examined the activity of the common first enzyme for the synthesis of nucleotide precursors of peptidoglycans, enoylpyruvate transferase by newly developed method. Both the specific and the total activity decreased after the end of exponential growth followed by and increase from t5 but decreased again parallel to the appearance of the activity of UDP_GlcNAc-4-epimerase. Antibody specificity to anti-transferase IgG and the elution profile on DEAE-Sepharose revealed that B. megaterium has at least two enoylpyruvate transferase isozymes, and UDP_GlcNAc was metabolized to vegetative cell wall and cortical peptidoglycan by each isozme in exponential growth and in sporulation, respectively in life cycle.

• BMB Reports
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• v.37 no.4
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• pp.503-506
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• 2004

Glucose-1-phosphate uridylyltransferase from E. coli K12 was used to convert uridine-5'-triphosphate and glucose-1-phosphate to UDP-D-glucose. The conversion was efficient and completed within 5 minutes under the employed conditions. In addition, thymidine-5'-monophosphate kinase and acetate kinase were proven to be non-specific, converting udridine-5'-monophosphate to uridine-5'-triphosphate with 55% conversion after 6 h, which was much slower than the production of TTP under the same conditions (complete conversion within one hour). Since these two reactions could proceed under the same conditions, a one-pot synthesis of UDP-D-glucose with ATP regeneration was designed from easily available starting materials, and conversion up to 40% by HPLC peak integration was achieved given a reaction time of 4 h.

• Journal of Sericultural and Entomological Science
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• v.40 no.2
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• pp.105-110
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• 1998

The baculovirus egt gene encodes an ecdysteroid UDP-glucosyltransferase(EGT) which catalyzes the transfer of glucose from UDP-glucose to the insect moltion hormone ecdysteroid resulting in a functionally inactive ecdysteroid. In baculovirus-infected insect larvae, EGT has been shown block molting and pupation. In this study, we compared the development of 4th and 5th instar silkworm, Bombyx mori, larvae injected with either wild-type bombyx mori nucleopolyhedrovirus (BmNPV) or a mutant BmNPV(BmEGTZ) in which the egt gene was disrupted by the insertion of a lacZ gene cassette. Larvae injected with BmEGTZ died roughly 12 h more rapidly compared to indentical larvae infected with BmNPV. In addition, BmEGTZ- infected larvae prematurely stopped feeding and gain less weight compared to BmNPV-infected larvae. In order to investigate why BmEGTZ-infected larvae died more rapidly than BmNPV-infected larvae, the array of hemolymph proteins in BmEGTZ-or BmNPV-infected larvae were analyzed by SDS-PAGE. The hemolymph of BmEGTZ-infected larvae showed virus-specific proteins, including polyhedrin, about 12 h earlier than the hemolymph of BmNPV-infected larvae

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.8
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• pp.1696-1702
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• 2005

Real Time Transport Protocol (RTP) is the Internet standard protocol for transport of real time data audio/video IP Telephony, Multimedia Seivece. In case of 8kbps voice codec, the size of packet per data is 20bytes and become more large to minimal 40bytes with adding each layer's header in RTP/UDP/IP. To solve this problem, various header compression skill were suggested on point-to-point networks. But it compress even IP header and cannot be suitable to apply to end-to-end network Thus, We will renew header compression protocol to apply wired router-based network.

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.1
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• pp.65-75
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• 2003

The internet telephony service is one of the successful internet application services. VoIP is the key technology for the service to come true. VoIP uses H.323 or SIP as the standard protocol for the distributed multimedia services over the internet environment, in which QoS is not guaranteed. VoIP carries the packetized voice by using the RTP/UDP/IP protocol stack. The UDP-based internet services cause the data transmission problem to the users behind the internet firewall. So does the internet telephony service. The users are not able to listen the voices of the counter-parts on the public internet or PSTN. It makes the problem more difficult that the internet telephony service addressed in this paper uses only one UDP port number to send the voice data of all sessions from gateway to terminal node. In this paper, two schemes including the usage of dummy UDP datagrams, and the protocol conversion are suggested. The implementation of one of the schemes, the protocol conversion, and the performance evaluation are described in detail.