Plant Growth Promotion in Soil by Some Inoculated Microorganisms

Jong-SooJeon,Sang-SooLee,Hyoun-YoungKim,Tae-SeokAhn,Hong-gyuSong 한국미생물학회 2003 The journal of microbiology Vol.41 No.4

The inoculation of some microorganisms into a microcosm containing soil from a barren lakeside area at Lake Paro in Kangwon-do enhanced plant growth significantly. The direct and viable counts of soil bacteria and soil microbial activities measured by electron transport system assay and fluorescein diacetate hydrolysis assay were higher in inoculated soil. The plant growth promoting effect of this inoculation may be caused by phytohormone production and the solubilization of insoluble phosphates by the inoculated bacteria. Three inoculated strains of Pseudomonas fluorescens produced several plant growth promoting phytohormones, including indole-3-acetic acid (auxin), which was confirmed by thin layer chromatography and GC/MS. P. fluorescens strain B16 and M45 produced 502.4 and 206.1 mg/l of soluble phosphate from Ca3(PO4)2 and hydroxyapatite, respectively. Bacillus megaterium showed similar solubilization rates of insoluble phosphates to those of Pseudomonas spp. We believe that this plant growth promoting capability may be used for the rapid revegetation of barren or disturbed land.

Hypoxia activates signal transducers and activators of transcription 5 (STAT5) and increases its binding activity to the GAS element in mammary epithelial cells

정연희,Jong-HwanPark,TaekyuPark,Chang-SooLee,OunHyunKim,Sang-KyuYe,UnMokYang,KwangJeonLee,YoungMokYang 생화학분자생물학회 2003 Experimental and molecular medicine Vol.35 No.5

STATs (signal transducers and activators of transcription) are proteins with dual functions: signal transducers in the cytoplasm and transcriptional activators in the nucleus. STAT proteins act as transcription factors activated by phosphorylation on its tyrosine residues upon stimulation by various cytokines. The phosphorylated STAT molecules then form homo- or heterodimers through SH2-mediated interaction and translocate into the nucleus to activate the transcription of various target genes. STAT5 recognizes the interferon-γ activated site TTCNNNGAA (GAS sequence) in the promoter region of the β-casein gene. Except for prolactin-dependent β-casein production in mammary gland cells, the biological consequences of STAT5a activation in various systems are not clear. Here we showed that STAT5a was phosphorylated 10 min after desferrioxamine (DFO) treatment, and reached a maximum induction at 4 h in mammary epithelial cells (HC11) and transfected COS-7 cells. Under hypoxic conditions (2% O2), a maximal phosphorylation of STAT5a was observed within 6 h. EMSA (electrophoretic mobility shift assay) showed that DFO or hypoxia enhanced the binding activities of STAT5a DNA to β-casein gene promoter in mammary epithelial cells (HC11) and transfected COS-7 cells. These results showed that DFO or hypoxia induces tyrosine phosphorylation of STAT5a and also increases the binding activity of STAT5a DNA in mammary epithelial cells. Our data suggest that the STAT5 may act as a mediator in hypoxiamediated gene expression.

Common-Mode Current on a Wire through a Corrugated Aperture

HyunHoPark,JaeWookLee,Jong-HwaKwon,Hyung-SooLee 한국전자통신연구원 2002 ETRI Journal Vol.24 No.6

This paper investigates the effect of a corrugated aperture on a common-mode current traveling along a penetrating wire. Computational results illustrate that the corrugated aperture acts as a filter, significantly reducing the commonmode current on the wire. This effect causes a reduction of radiated emission from cables passing through apertures on shielding enclosures. To predict and analyze the characteristics of the common-mode current on a straight wire passing through a corrugated aperture with cylindrical symmetry, the finite-difference time-domain (FDTD) method is applied.

Novel wet-free interfacial affinity modulation of non-polar polymers for imparting efficient heat transfer capability to incompatible polypropylene/graphite nanoplatelet composite

김민성,Jiwan You,Jong Hyuk Park,Joona Bang,Sang-SooLee 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.107 No.-

In preparing a non-polar polymer composite employing functional fillers, the chemical inertness of nonpolarpolymer does not easily allow efficient interfacial affinity change. Here, a wet-free interfacial affinitymodulation to incompatible polypropylene (PP)/graphite nanoplatelet (GNP) composite was performedwith a nitrogen plasma-assisted mechanochemical (PM) treatment. It was surprising that thePP/GNP composite subjected to the PM treatment demonstrated the formation of chemical bondsbetween PP and GNP and the dramatic improvement of GNP dispersion in PP, resulting in a novel PP compositedeploying efficient heat transfer along with mechanical performance comparable to that of neatPP. Due to the interfacial affinity control, the elongation at break of the PM-treated PP/GNP compositewith 5 wt% of GNP was improved ten-folds compared to the untreated PP/GNP composite. The thermalconductivity of the PM-treated PP/GNP composite employing 20 wt% of GNP reached ca. 21 W/mK,whereas the untreated PP/GNP composite containing comparable amount of GNP exhibited 7 W/mK. Based on the findings, it can be noted that a solvent-free plasma-assisted mechanochemical treatmentcould be meaningful in developing a novel composite capable of efficient mechanical load transfer andheat transfer with non-polar polymers known to be poor at chemical reaction.

Expression of Angiostatin Using DNA-Based Semliki Forest Virus Replicon

Chul-Joong Kim,Jong-SooLee,Young-KiChoi,Kwang-SoonShin,Hyun-SooKim 대한수의학회 2002 Journal of Veterinary Science Vol.3 No.1

Angiogenesis recognized as a critical factor inthe growth of tumor cels and plays a key role in thetumor metastasis. Recent studies for antiangiogenicsubstances are geting popular. The angiostatin, oneof the antiangiogenic substances, leads to theincreased apoptosis of the tumor cels by inhibitingthe neovascularization of the tumor. The angiostatinwas identified as the internal fragments of theplasminogen which has no antiangiogenic activity. Byproduced. In this tudy, we constructed the SFV-derivedDNA vector by employing the cytomegalovirusimediate arly enhancer/ promoter (CMV). Thisvector makes it possible to transfect the cells withDNA without the in vitro transcription proces. TheC-myc epitope and polyhistidine residue sequenceswere placed in downstream of the angiostatin gene tomake it eligible to detect the xpresed protein. Themurine Ig κ-chain V-J2-C signal sequence was placedin upstream to secrete the xpresed protein from thecels. We confirmed the xpresion of angiostatin

Intracellular sensing of viral genomes and viral evasion

Hyun-Cheol Lee,Kiramage Chathuranga,Jong-SooLee 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

During viral infection, virus-derived cytosolic nucleic acids are recognized by host intracellular specific sensors. The efficacy of this recognition system is crucial for triggering innate host defenses, which then stimulate more specific adaptive immune responses against the virus. Recent studies show that signal transduction pathways activated by sensing proteins are positively or negatively regulated by many modulators to maintain host immune homeostasis. However, viruses have evolved several strategies to counteract/evade host immune reactions. These systems involve viral proteins that interact with host sensor proteins and prevent them from detecting the viral genome or from initiating immune signaling. In this review, we discuss key regulators of cytosolic sensor proteins and viral proteins based on experimental evidence.

High Performance RF Passive Integration on a Si Smart Substrate for Wireless Applications

Dong-WookKim,권영세,In-HoJeong,Jong-SooLee 한국전자통신연구원 2003 ETRI Journal Vol.25 No.2

To achieve cost and size reductions, we developed a low cost manufacturing technology for RF substrates and a high performance passive process technology for RF integrated passive devices (IPDs). The fabricated substrate is a conventional 6″ Si wafer with a 25 μm thick SiO2 surface. This substrate showed a very good insertion loss of 0.03 dB/mm at 4 GHz, including the conductive metal loss, with a 50 Ω coplanar transmission line (W=50 μm, G=20 μm). Using benzo cyclo butene (BCB) interlayers and a 10 μm Cu plating process, we made high Q rectangular and circular spiral inductors on Si that had record maximum quality factors of more than 100. The fabricated inductor library showed a maximum quality factor range of 30-120, depending on geometrical parameters and inductance values of 0.35-35 nH. We also fabricated small RF IPDs on a thick oxide Si substrate for use in handheld phone applications, such as antenna switch modules or front end modules, and high-speed wireless LAN applications. The chip sizes of the wafer-levelpackaged RF IPDs and wire-bondable RF IPDs were 1.0- 1.5 mm2 and 0.8-1.0 mm2, respectively. They showed very good insertion loss and RF performances. These substrate and passive process technologies will be widely utilized in hand-held RF modules and systems requiring low cost solutions and strict volumetric efficiencies.