• Journal of Life Science
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• v.8 no.6
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• pp.702-710
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• 1998

The perillas were cultivated to investigate for the small metal ion effect on the harvest of perilla loaves in aquicul-ture system in the constant flow rate. The perillas were und-ergrown at the condition of low concentration of KNO$_3$and NH$_4$ H$_2$ PO$_4$as below 270ppm and 152ppm respectively. The high concentration of the metal and non-metal ca-tions of $Ca^{2+}$, $K^+,NH^{4+},Mn^{2+},Zn^{2+},Cu^{2+},Na^+,Mo^{+6}$ are influenced to the growth of plant length of perillas at the earlier time. The low concentration of the metal cations of $Ca^{2+}, K^+, NH^{4+}, NO_3^-, H_2PO_4^-$ are influenced to lower growth of perillas. The concentration of the cations of $Ca^{2+}, K^+$and $NH_4^+$ and the anions of $NO_3^-$and $H_2PO_4^-$ are affected the growth of leaf length and width of leaf of perillas. The spectoscopic analytical results showed that the perillas were growing rapidly in the period of 6 days from June 7 to June 12 by high amount of $Mg^{2+}$ ion with accumulation inside perillas. The crude protein, the crude fat and the hydrocarbon are accumulated in the leaves of perillas by binding the inorganic with amino acids to provide the nutritions needed for growth of perillas.

• Journal of Microbiology
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• v.35 no.4
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• pp.309-314
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• 1997

The manganese-containing superoxide dismutase (MnSOD) is a major component of the cellular defence mechanisms against the toxic effects of the superoxide radical. Within the framework of studies on oxidative stress=responsible enzymes in the Candida sp., the gene encoding the MnSOD was isolated and examined in this study. A specific primer was designed based on conserved regions of MnSOD sequences from other organisms, and was used to isolate the gene by PCR on reverse-transcribed Candida poly($A^{+}$) RNA. The PCR product was used to screen a Candida genomic lambda library and the nucleotide wequence of positive clone was determined. The deduced primary sequence encodes a 25kDa protein which has the conserved residues for enzyme activity and metal binding. The 28 N-terminal amino acids encoded by the Candida cDNA comprise a putatice mitochondrial transit peptide. Potential regulatory elements were identified in the 5' flanking sequences. Northern blot analysis showed that the transcription of the MnSOD gene is induced 5-to 10-fold in response to mercury, cadmium ions and hydrogen peroxide.

• Korean Journal of Veterinary Research
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• v.47 no.1
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• pp.25-32
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• 2007

Houttuynia cordata root on non-lipid oxidative damage. The antioxidative efects of methanolic (MeOH) extract of Houttuynia cordata rooton non-lipid, including liposome oxidation, oxidation of deoxyribose, protein oxidation, chelating, scavenging,and 2'-deoxyguanosine (2'dG) oxidation were investigated. Houttuynia cordata root exhibited highantioxidative effect in a liposome model system. The inhibitory effect of MeOH extract on deoxyribosedamage exhibited antioxidative effect and it afforded considerable protection against damage to deoxyribose.In addition, MeOH extract at over 300extracts exhibited metal binding ability for hydrogen peroxide. Furthermore, the oxidation of 2'dG to 8-hydroxy-2-deoxyguanosine was inhibited by MeOH extracts, and scavenging activity for hydroxyl radicalexhibited a remarkable effect. The present results on biological model systems showed that MeOH extractswas effective in the protection of non-lipids against various oxidative model systems.

• Applied Chemistry for Engineering
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• v.23 no.6
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• pp.515-520
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• 2012

In this review, the fabrication of silicon based memory capacitor and organic memory thin film transistors (TFTs) was discussed for their potential identification tag applications and biosensor applications. Metal or non-metal nanoparticles (NPs) could be capped with chemicals or biomolecules such as protein and oligo-DNA, and also be self-assembly monolayered on corresponding target biomolecules conjugated dielectric layers. The monolayered NPs were formed to be charging elements of a nano floating gate layer as forming organic memody deivces. In particular, the strong and selective binding events of the NPs through biomolecular interactions exhibited effective electrostatic phenomena in memory capacitors and TFTs formats. In addition, memory devices fabricated as organic thin film transistors (OTFTs) have been intensively introduced to facilitate organic electronics era on flexible substrates. The memory OTFTs could be applicable eventually to the development of new conceptual devices.

• Journal of Preventive Medicine and Public Health
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• v.37 no.4
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• pp.329-336
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• 2004

Objectives : Iron (Fe) is an essential element in biological processes; however excessive Fe is harmful to human health. Some air pollutants contain a high level of Fe, and the human lung could therefore be over-exposed to Fe through inhaled air pollutants. This study was performed to investigate the role of metal transporters (divalent metal transporter 1, DMT1, and metal transporter protein 1, MTP1) in the lung under the environments of Fe deficiency in the body and Fe over-exposure in the lung. Methods : Rats were fed Fe deficient (FeD, 2-6 mg Fe/kg) or Fe supplemented (FeS, 120 mg Fe/kg) diet for 4 weeks, followed by a single intratracheal instillation of ferrous sulfate at low (10 mg/kg) or high (20 mg/kg) dose. Fe concentration was analyzed in the serum, lung and liver, and histopathological findings were observed in the lung at 24 hours after Fe administration. The level of DMT1 and MTP1 expression in the lung was analyzed by RT-PCR. Also, the effect of Fe deficiency in the body was evaluated on the level of Fe concentration and metal transporters compared to FeS-diet fed rats at the end of 4-week FeD or FeS diet. Results : The 4-week FeD diet in rats induced an Fe deficiency anemia with decreased serum total Fe, increased unsaturated Fe binding capacity and hypochromic microcytic red blood cells. The concentration of Fe in the lung and liver was lower in the FeD-diet fed rats than in the FeS-diet fed rats. The level of metal transporters mRNA expression was higher in the FeD-diet fed rats than in the FeS-diet. The concentration of Fe in the lung was increased in a dose-dependent pattern after intratracheal instillation of Fe into the rats, while the level of Fe in the serum and liver was not increased in the low-dose Fe administered rats. Therefore, DMT1 and MTP1 mRNA was highly expressed in both FeD-diet and FeS-diet fed rats, after intratracheal instillation of Fe. Conclusions : DMT1 and MTP1 mRNA were more highly expressed in FeD-diet fed rats than in FeS-diet fed rats. The over-exposure of Fe intratracheally induced high expression of metal transporters and increased Fe deposition in the lung in both FeD-diet and FeS-diet fed rats, but did not increase the Fe level of the serum and liver in low-dose Fe administered rats. These results suggest that the role of metal transporters in the lung might be different in a part from the duodenum under the environment of over-exposure to Fe.

• Journal of Microbiology and Biotechnology
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• v.11 no.1
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• pp.153-159
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• 2001

In order to clone the peptide synthetase gene form Lysobacter lactamgenus IFO 14,288, the gene fragments were amplified using primers for the adenylation domain and the thionylation domain of the peptide synthetase genes in other organisms by polymerase chain reaction (PCR). The resulting 0.5-kb fragment was cloned in a pGEM-T vector, and the nucleotide sequences were determined. Six different PCR products were obtained; three were identified to be a part of L-$\alpha$-aminoadipyl-L-cysteinyl-D-valine (ACV) synthetase and three to be other peptide synthetases. Using each of the two different classes of PCR products as mixed probes, a cosmid library of L. lactamgenus chromosomal DNA constructed in a pHC79 vector was screened by an in situ hybridization procedure, and one positive clone was selected which was bound by peptide synthetase gene fragments as well as ACV synthetase gene fragments. The partial sequence analysis formt he obtained pPTS-5 cosmid showed th presence of more than two open reading frames. These were for two putative membrane transporters, which were homologous with several integral membrane proteins including the ABC transporter ATP-binding protein of E. coli (YbjZ) and the metal ion uptake protein of Bacillus subtilis (YvrN). A 45% homology was also found between the two transporter proteins at the carboxy terminus. Through a hydropathy analysis and transmembrane analysis. 4-5 transmembrane domains were found in these two proteins. When the genes were expressed in Escherichia coli, the gene products inhibited the hose cell growth, probably due to the disturbance of the membrane transport system.

• Journal of Microbiology and Biotechnology
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• v.30 no.8
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• pp.1261-1271
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• 2020

Cytochrome c_L (Cytc_L) is an essential protein in the process of methanol oxidation in methylotrophs. It receives an electron from the pyrroloquinoline quinone (PQQ) cofactor of methanol dehydrogenase (MDH) to produce formaldehyde. The direct electron transfer mechanism between Cytc_L and MDH remains unknown due to the lack of structural information. To help gain a better understanding of the mechanism, we determined the first crystal structure of heme c containing Cytc_L from the aquatic methylotrophic bacterium Methylophaga aminisulfidivorans MP^T at 2.13 Å resolution. The crystal structure of Ma-Cytc_L revealed its unique features compared to those of the terrestrial homologues. Apart from Fe in heme, three additional metal ion binding sites for Na⁺, Ca⁺, and Fe²⁺ were found, wherein the ions mostly formed coordination bonds with the amino acid residues on the loop (G93-Y111) that interacts with heme. Therefore, these ions seemed to enhance the stability of heme insertion by increasing the loop's steadiness. The basic N-terminal end, together with helix α4 and loop (G126 to Y136), contributed positive charge to the region. In contrast, the acidic C-terminal end provided a negatively charged surface, yielding several electrostatic contact points with partner proteins for electron transfer. These exceptional features of Ma-Cytc_L, along with the structural information of MDH, led us to hypothesize the need for an adapter protein bridging MDH to Cytc_L within appropriate proximity for electron transfer. With this knowledge in mind, the methanol oxidation complex reconstitution in vitro could be utilized to produce metabolic intermediates at the industry level.

• Journal of Plant Biotechnology
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• v.4 no.1
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• pp.7-15
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• 2002

Eight cDNAs corresponding to fruit-specific genes were isolated from ripened melon through differential screening. Sequence comparison indicated that six of these cDNAs encoded proteins were previously characterized into aminocyclopropane-1-carboxylate (ACC) oxidase, abscisic acid, stress and ripening inducible (ASR) gene, RINC-H2 zinc finger protein, pyruvate decarboxylase, or polyubiquitin. RFS2 and RFS5 were the same clone encoding polyubiquitin. The other cDNAs showed no significant homology with known protein sequences. The ASR homologue (Asr1) gene was further characterized on the cDNA and genomic structure. The deduced amino acid sequence had similar characteristics to other plant ASR. The Asr1 genomic DNA consisted of 2 exons and 1 intron, which is similar to the structure of other plants ASR genes. The promoter region of the Asr1 gene contained several putative functional cis-elements such as an abscisic acid responsive element (ABRE), an ethylene responsive element (ERE), a C-box or DPBf-1 and 2, Myb binding sites, a low temperature responsive element (LTRE) and a metal responsive element (MRE). The findings imply that these elements may play important roles in the response to plant hormones and environmental stresses in the process of fruit development. The results of this study suggest that the expressions of fruit specific and ripening-related cDNAs are closely associated with the stress response.

• Analytical Science and Technology
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• v.8 no.3
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• pp.221-227
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• 1995

The fiber optic fluorosensor that shows a specific selectivity for calcium ion is studied. This sensor employs protein Calmodulin(CaM) which forms a fluorescent chelate with $Ca^{2+}$. A dialysis membrane is used to entrap a fluorescein isothiocyanate-labeled CaM solution at the common end of a bifurcated fiber optic bundle. The sensing mechanism of this sensor is based on the shifts in the fluorescence spectrum of metal-calmodulin complexes which FCaM forms a chelate with $Ca^{2+}$. Upon binding with $Ca^{2+}$, CaM undergoes a conformational change which induces a change in the fluorescence of FCaM. This change in fluorescence signal which is measured by photomultiflier tube is related to the concentration of $Ca^{2+}$ for calibration curve. Detection limit for $Ca^{2+}$ and the interference effects by $Mg^{2+}$, $Eu^{3+}$ and $La^{3+}$ for this sensor are studied. Response time and life time for this fluorosensor are also investigated.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.2
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• pp.144-149
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• 2001

For the production and purification of a single chain human insulin precursor, four types of fusion peptides $\beta$-galactosidase (LacZ), maltose binding protein (MBP), glutathione-S-transferase (GST), and (His)(sub)6-tagged sequence (HTS) were investigated. Recombinant E. coli harboring hybrid genes was cultivated at 37$\^{C}$ for 1h, and gene induction occurred when 0.2mM of isopropyl-D-thiogalactoside (IPTG) was added to the culture broth, except for E. coli BL21 (DE3) pLysS harboring a pET-BA cultivation with 1.0mM IPTG, followed by a longer than 4h batch fermentation respectively. DEAE-Sphacel and Sephadex G-200 gel filtration chromatography, amylose affinity chromatography, glutathione-sepharose 4B affinity chromatography, and a nickel chelating affinity chromatography system as a kind of immobilized metal ion affinity chromatography (IMAC) were all employed for the purification of a single chain human insulin precursor. The recovery yields of the HTS-fused, GST-fused, MBP-fused, and LacZ-fused single chain human insulin precursors resulted in 47%, 20%, 20%, and 18% as the total protein amounts respectively. These results show that a higher recovery yield of the finally purified recombinant peptides was achieved when affinity column chromatography was employed and when the fused peptide had a smaller molecular weight. In addition the pET expression system gave the highest productivity of a fused insulin precursor due to a two-step regulation of the gene expression, and the HTS-fused system provided the highest recovery of a fused insulin precursor based on a simple and specific separation using the IMAC technique.