• The Journal of Korean Society of Virology
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• v.29 no.3
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• pp.175-182
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• 1999

An attractive target for anti-herpes chemotherapy is the herpes simplex virus 1 (HSV-1) protease encoded by the UL26 gene. HSV-1 protease is essential for DNA packaging and virus maturation. To perform high throughput for potent inhibitors, the efficient production of larger amounts of highly purified enzyme and protease activity assay method must be established. In this report, expression in E. coli and purification of the protease gene of HSV-1 strain F was investigated. The protease gene was cloned pET28, and the nucleotide sequence of protease catalytic domain of HSV-1 compared strain F with other strains (KOS and CL101). In these results the F strain was different in base sequence. However, the amino acid sequence was identifical. The HSV-1 protease was purified with His-tagged affinity column. The analysis of HSV-1 protease activity was performed by high performance liquid chromatography.

• Molecular & Cellular Toxicology
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• v.1 no.1
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• pp.17-25
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• 2005

There are some critical drawbacks in the use of biomarkers for a global assessment of the toxicological impacts many chemicals and environmental pollutants have, primarily due to an individual biomarker's specificity for an explicit chemical or toxicant. In other words, the biomarker-based assessment methodology used to analyze toxicological effects lacks a high-throughput capability. Therefore, eco-toxicogenomics, or the study of toxicogenomics with organisms present within a given environmental locale, has recently been introduced with the advent of the so-called "-omics" era, which began with the creation of microarray technologies. Fish are comparable with humans in their toxicological responses and thus data from toxicogenomic studies performed with fish could be applied, with appropriate tools and implementation protocols, to the evaluation of environments where human or animal health is of concern. At present, there have been very active research streams for developing expression sequence tag (EST) databases (DBs) for zebra fish and rainbow trout. Even though few reports involve toxicogenomic studies with fish, a few groups have successfully fabricated and used cDNA microarrays or oligo DNA chips when studying the toxicological impacts of hypoxia or some toxicants with fish. Furthermore, it is strongly believed that this technology can also be implemented with non-model fish. With the standardization of DNA microarray technologies and ample progress in bioinformatics and proteomic technologies, data obtained from DNA microarray technologies offer not only multiple biomarker assays or an analysis of gene expression profiles, but also a means of elucidating gene networking, gene-gene relations, chemical-gene interactions, and chemical-chemical relationships. Accordingly, the ultimate target of eco-toxicogenomics should be to predict and map the pathways of stress propagation within an organism and to analyze stress networking.

• Development and Reproduction
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• v.14 no.4
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• pp.215-223
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• 2010

The construction of transgenic mouse using embryonic stem (ES) cells has been crucial in the functional studies of gene on mouse genome. Gene knockout mice have been powerful for elucidating the function of genes as well as a research model for human diseases. Gene targeting and gene trapping mathods have been the representative technologies for making the knockout mice by using ES cells. Since the gene targeting and the gene trapping methods were independently developed about 20 years ago, it's efficiency and productivity has been improved with a advance of molecular biology. Conventional gene targeting method has been changes to high throughput conditional gene targeting. The combination of the advantage of gene targeting and gene tapping elements allows to extend a spectrum of gene trapping and to improve the efficiency of gene targeting. These advance should be able to produce the mutant with various phenotype to target a certain gene, and in postgenome era they have served as crucial research tools in understanding the functional study of whole genome in mouse.

• Journal of Microbiology and Biotechnology
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• v.23 no.5
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• pp.587-601
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• 2013

During the last few decades, it has become evident that the compatibility of the yeast biochemical environment with the ability to process and translate the RNA transcript, along with its capacity to modify a translated protein, are relevant requirements for selecting this host cell for protein expression in several pharmaceutical and clinical applications. In particular, Pichia pastoris is used as an industrial host for recombinant protein and metabolite production, showing a powerful capacity to meet required biomolecular target production levels in high-throughput assays for functional genomics and drug screening. In addition, there is a great advantage to using P. pastoris for protein secretion, even at high molecular weights, since the recovery and purification steps are simplified owing to relatively low levels of endogenous proteins in the extracellular medium. Clearly, no single microexpression system can provide all of the desired properties for human protein production. Moreover, chemical and physical bioprocess parameters, including culture medium formulation, temperature, pH, agitation, aeration rates, induction, and feeding strategies, can highly influence product yield and quality. In order to benefit from the currently available wide range of biosynthesis strategies using P. pastoris, this mini review focuses on the developments and technological fermentation achievements, providing both a comparative and an overall integration analysis. The main aim is to highlight the relevance and versatility of the P. pastoris biosystem to the design of more cost-effective microfactories to meet the increasing demands for recombinant membrane proteins and clinical antibodies for several therapeutic applications.

• BMB Reports
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• v.40 no.6
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• pp.1058-1068
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• 2007

The post-translational modifications of Ser and Thr residues by O-linked $\beta$-N-acetylglucosamine (O-GlcNAc), i.e., O-GlcNAcylation, is considered a key means of regulating signaling, in a manner analogous to protein phosphorylation. Furthermore, it has been suggested that the increased flux of glucose through the hexosamine biosynthetic pathway (HBP) stimulates O-GlcNAcylation, and that this may be responsible for many of the manifestations of type 2 diabetes mellitus. To determine whether excessive O-GlcNAcylation of target proteins results in pancreatic $\beta$ cell dysfunction, we increased nucleocytoplasmic protein O-GlcNAcylation levels in $\beta$ cells by exposing them to streptozotocin and/or glucosamine. Streptozotocin and glucosamine co-treatment increased O-GlcNAcylated proteomic patterns as assessed by immunoblotting, and these increases in nuclear and cytoplasmic protein O-GlcNAcylations were accompanied by impaired insulin secretion and enhanced apoptosis in pancreatic $\beta$ cells. This observed $\beta$cell dysfunction prompted us to examine Akt and Bcl-2 family member proteins to determine which proteins are O-GlcNAcylated under conditions of high HBP throughput, and how these proteins are associated with $\beta$ cell apoptosis. Eventually, we identified ten new O-GlcNAcylated proteins that were expressed during $\beta$ cell apoptosis, and analyzed the functional implications of these proteins in relation to pancreatic $\beta$ cell dysfunction.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.2
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• pp.77-82
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• 2013

PKMv2 security protocol was adopted by the WiMax2 mobile internet communication standard. A base station and a mobile station protect communication data using key based encryption according to the PKMv2 protocol. Consequently, each development of a base station and/or mobile station includes implement of the PKMv2 protocol, and the station must qualifies various interoperable tests. Furthermore, communication bandwidth of the station can be limited by the encryption module when the station implemented based on a low-performance processor. Thus, a correspondence measurement of the encryption module must be carried on the target processor. In this paper, we implement a testbed which affords throughput measurement as well as the interoperable tests by PKMv2.

• Bulletin of the Korean Chemical Society
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• v.26 no.2
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• pp.285-291
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• 2005

The nonstructural protein 5B (NS5B) of hepatitis C virus (HCV) is the viral RNA-dependent RNA polymerase (RdRp), which is the essential catalytic enzyme for the viral replication and is an appealing target for the development of new therapeutic agents against HCV infection. A small amount of serum from a single patient with hepatitis C was used to get the genome of a Korean HCV isolate. Sequence analysis of NS5B 1701 nucleotides showed the genotype of a Korean isolate to be subtype 1b. The soluble recombinant HCV NS5B polymerase lacking the C-terminal 24 amino acids was expressed and purified to homogeneity. With the highly purified NS5B protein, we established in vitro systems for RdRp activity to identify potential polymerase inhibitors. The rhodanine family compounds were found to be potent and specific inhibitors of NS5B from high throughput screening (HTS) assay utilizing the scintillation proximity assay (SPA) system. The binding mode of an inhibitor was analyzed by measuring various kinetic parameters. Lineweaver-Burk plots of the inhibitor suggested it binds not to the active site of NS5B polymerase, but to an allosteric site of the enzyme. The activity of NS5B in in vitro polymerase reactions with homopolymeric RNA requires interaction with multiple substrates that include a template/primer and ribonucleotide triphosphate. Steady-state kinetic parameter, such as Km, was determined for the ribonucleotide triphosphate. One of compounds found interacts directly with the viral polymerase and inhibits RNA synthesis in a manner noncompetitively with respect to UTP. Furthermore, we also investigated the ability of the compound to inhibit NS5B-directed viral RNA replication using the Huh7 cell-based HCV replicon system. The investigation is potentially very useful for the utility of such compounds as anti-hepatitic agents.

• Journal of Convergence for Information Technology
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• v.10 no.5
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• pp.1-7
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• 2020

This paper proposes a link adaptation method for Underwater Internet of Things (IoT), which reduces power consumption of sensor nodes and improves the throughput of network in underwater IoT network. Adaptive Modulation and Coding (AMC) technique is one of link adaptation methods. AMC uses the strong correlation between Signal Noise Rate (SNR) and Bit Error Rate (BER), but it is difficult to apply in underwater IoT as it is. Therefore, we propose the machine learning based AMC technique for underwater environments. The proposed Modulation Coding and Scheme (MCS) prediction model predicts transmission method to achieve target BER value in underwater channel environment. It is realistically difficult to apply the predicted transmission method in real underwater communication in reality. Thus, this paper uses the high accuracy BER prediction model to measure the performance of MCS prediction model. Consequently, the proposed AMC technique confirmed the applicability of machine learning by increase the probability of communication success.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2000.11a
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• pp.74-82
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• 2000

Prostate cancer initially responds and regresses in response to androgen depletion therapy, but most human prostate cancers will eventually recur, and re-grow as an androgen independent tumor. Once these tumors become hormone refractory, they usually are incurable leading to death for the patient. Little is known about the molecular details of how prostate cancer cells regress following androgen ablation and which genes are involved in the androgen independent growth following the development of resistance to therapy. Such knowledge would reveal putative drug targets useful in the rational therapeutic design to prevent therapy resistance and control androgen independent growth. The application of genome scale technologies have permitted new insights into the molecular mechanisms associated with these processes. Specifically, we have applied functional genomics using high density cDNA microarray analysis for parallel gene expression analysis of prostate cancer in an experimental xenograft system during androgen withdrawal therapy, and following therapy resistance, The large amount of expression data generated posed a formidable bioinformatics challenge. A novel template based gene clustering algorithm was developed and applied to the data to discover the genes that respond to androgen ablation. The data show restoration of expression of androgen dependent genes in the recurrent tumors and other signaling genes. Together, the discovered genes appear to be involved in prostate cancer cell growth and therapy resistance in this system. We have also developed and applied tissue microarray (TMA) technology for high throughput molecular analysis of hundreds to thousands of clinical specimens simultaneously. TMA analysis was used for rapid clinical translation of candidate genes discovered by cDNA microarray analysis to determine their clinical utility as diagnostic, prognostic, and therapeutic targets. Finally, we have developed a bioinformatic approach to combine pharmacogenomic data on the efficacy and specificity of various drugs to target the discovered prostate cancer growth associated candidate genes in an attempt to improve current therapeutics.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.11B
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• pp.1178-1190
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• 2009

IEEE 802.11e proposed by IEEE 802.11 working group to guarantee QoS has contention based EDCA and contention free based HCCA. HCCA, a centralized polling based mechanism of 802.11e, needs a scheduling algorithm to allocate the network resource efficiently. The existing standard scheduler, however, is inefficient to support for QoS guarantee for real-time service having VBR traffic. To efficiently assign resource for VBR traffic, in this paper, we propose TXOP algorithm based on dual leaky bucket using average resource allocation and peak resource allocation. The minimum TXOP of each station is obtained by using statistical approach to maximize number of stations of which performance satisfy QoS target. Simulation results show that the proposed algorithm has much higher performance compared with reference scheduler in terms of throughput and delay.