http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
GSH-dependent peroxidase activity of the rice (Oryza sativa) glutaredoxin, a thioltransferase
Lee, Kyun-Oh,Lee, Jung-Ro,Yoo, Ji-Young,Jang, Ho-Hee,Moon, Jeong-Chan,Jung, Bae-Gyo,Chi, Yong-Hun,Park, Soo-Kwon,Lee, Seung-Sik,Lim, Chae-Oh,Yun, Dae-Jin,Cho, Moo-Je,Lee, Sang-Yeol Plant molecular biology and biotechnology research 2002 Plant molecular biology and biotechnology research Vol.2002 No.-
Glutaredoxin (Grx) is a 12-kDa thioltransoferase that reduces disulfide bonds of other proteins and maintains the redox potential of cells. In addition to its oxidoreductase activity, we report here that a rice Grx(OsGrx) can also function as a GSH-dependent peroxidase. Because of this antioxidant activity, OsGrx protects glutamine synthetase from oxidative damage. Individually replacing the conserved Cys residues in OsGrx with Ser shows that Cys^(23), but not Cys^(26), is essential for the thioltransferase and GSH-de-pendent peroxidase activities. Kinetic Characterization of OsGrx reveals that the maximal catalytic efficiency (V_(max)/K_(m))is obtained with cumene hydroperoxide rather than H_(2)O_(2) or t-butyl hydroperoxide.
한국(韓國)의 인구변화(人口變化)와 경제발전(經濟發展) 경제(經濟)모델을 중심(中心)으로
노공균 ( Kong Kyun Ro ),조남훈 ( Nam Hoon Cho ),박대근 ( Dae Keun Park ) 한국보건사회연구원 1983 保健社會硏究 Vol.3 No.1
The purposes of this paper are to formulate an economic-demographic growth model for Korea and to analyse the policy impacts on population change and economic development. It is hoped that the result of this study would contribute to formulating a more efficient economic- demographic policy. An economic-demographic growth model for Korea is formulated on the basis of the Suits- Mason model and other relevant models. The equations which explain the level of economic variables in the model are estimate by econometric methods using time-series data. Four variables are selected as policy variables. They are total fertility rate (TFR), marginal growth capital formation rate (MGCFR), high school education rate of the working age population (RHE), and emigration rate (EMR). A each different scenario is assigned to each of these variables, and the future levels of economic and demographic variables under these scenarios are calculated using simulation methods. Then, economic gains from each policy are computed to provide a basis for appraising alternative policies. The major findings from this study are as follows. The target fertility control policy is efficient in reducing the population growth rate and in increasing the GNP growth rate. The investment policy and education policy contribute to a rapid economic growth by increasing both capital stock and human capital. The emigration policy has a direct significant effect on the size of population, but has an insignificant effect on economic growth. If the policy mix of the fertility control policy and the investment policy is used, the economic gain will be greater than the sum of the economic gains from each policy. That indicates that syneric effect may be obtained by combining appropriate policies. In conclusion, a proper mix of various policies is essential to obtain a balanced and rapid economic growth through syneric effects.
부식환경하에서 Al 7075-T6의 피로수명에 미치는 쇼트피닝의 효과에 관한 연구
정성균(Seong-Kyun Cheong),남지헌(Ji-Hun Nam),구대림(Dae-Lim Kou),노승남(Seung-Nam Ro) 한국항공우주학회 2005 韓國航空宇宙學會誌 Vol.33 No.2
부식은 기계류나 금속 부품의 성능과 수명을 저해하는 가장 큰 요인으로 작용하고 있다. 이 논문에서는 쇼트피닝이 부식환경하에서 Al 7075-T6의 피로수명에 미치는 쇼트피닝의 효과를 연구하였다. 쇼트피닝한 시험편의 피로한도는 약 52% 증가하는 것으로 나타났으며, 금속재 부품의 피로수명을 크게 연장시키는 것으로 보인다. 쇼트피닝을 한 시험편과 쇼트피닝 하지 않은 시험편을 1주에서 1년까지 비교 시험한 결과 부식은 피로강도를 현격히 감소시켰다. 쇼트피닝을 하였을 경우에는 부식에 의해 6개월 까지는 피로강도 및 피로 수명이 감소하지 않은 것으로 나타났다. 따라서 쇼트피닝 가공이 금속재료의 수명에 대한 부식의 영향을 크게 감소시키는 효과가 있음을 알 수 있다. Corrosion highly affects the lifetime and performance of machinery metallic components. The effects of shot peening on the fatigue life of Al 7075-T6 under corrosive environment are investigated in this paper. Experimental results show that the fatigue limit of shot peened specimen increases about 52%. That means the fatigue life of metallic components is highly extended by shot peening. The corrosion greatly reduces the fatigue strength depending on the corrosive condition from one week up to one year. In case of shot peened specimen, the corrosion does not reduce the fatigue strength and fatigue life up to six months. It means that the shot peening has superior effectiveness to reduce the influence of corrosion to the metallic materials.
Jin Zhehao,Ro Dae-Kyun,Kim Soo-Un,Kwon Moonhyuk 한국응용생명화학회 2022 Applied Biological Chemistry (Appl Biol Chem) Vol.65 No.2
Piperonal is a simple aromatic aldehyde compound with a characteristic cherry-like aroma and has been widely used in the flavor and fragrance industries. Despite piperonal being an important aroma in black pepper ( Piper nigrum ), its biosynthesis remains unknown. In this study, the bioinformatic analysis of the P. nigrum transcriptome identified a novel hydratase-lyase, displaying 72% amino acid identity with vanillin synthase, a member of the cysteine proteinase family. In in vivo substrate-feeding and in vitro enzyme assays, the hydratase-lyase catalyzed a side-chain cleavage of 3,4-methylenedioxycinnamic acid (3,4-MDCA) to produce 3,4-methylenedioxybenzaldehyde (piperonal) and thus was named piperonal synthase (PnPNS). The optimal pH for PnPNS activity was 7.0, and showed a K m of 317.2 μM and a k cat of 2.7 s −1 . The enzyme was most highly expressed in the leaves, followed by the fruit. This characterization allows for the implementation of PnPNS in various microbial platforms for the biological production of piperonal.
Lee, Jung Ro,Jang, Ho Hee,Park, Jin Ho,Jung, Ji Hyun,Lee, Seung Sik,Park, Soo Kwon,Chi, Yong Hun,Moon, Jeong Chan,Lee, Young Mee,Kim, Sun Young,Kim, Jae-Yean,Yun, Dae-Jin,Cho, Moo Je,Lee, Kyun Oh,Lee, Blackwell Publishing Ltd 2006 The Plant journal Vol.47 No.3
<P>Summary</P><P>Using the rice <I>PEX14</I> cDNA as a bait in a yeast two-hybrid assay, two splice variants of the type I peroxisomal targeting signal (PTS1) receptor, <I>Os</I>Pex5pL and <I>Os</I>Pex5pS, were cloned from a pathogen-treated rice leaf cDNA library. The proteins were produced from a single gene by alternative splicing, which generated a full-length variant, <I>OsPEX5L</I>, and a variant that lacked exon 7, <I>OsPEX5S</I>. <I>Os</I>Pex5pL contained 11 copies of the pentapeptide motif WXXXF/Y in its N-terminus, and seven tetratricopeptide repeats in its C-terminus. Expression of <I>OsPEX5L</I> and <I>OsPEX5S</I> predominantly occurred in leaf tissues, and was induced by various stresses, such as exposure to the pathogen <I>Magnaporthe grisea</I>, and treatment with fungal elicitor, methyl viologen, NaCl or hydrogen peroxide. The Arabidopsis T-DNA insertional <I>pex5</I> mutant, <I>Atpex5</I>, which does not germinate in the absence of sucrose and was resistant to indole-3-butyric acid (IBA), was perfectly rescued by over-expression of <I>Os</I>Pex5pL, but not by <I>Os</I>Pex5pS. Using transient expression of <I>Os</I>Pex5pL and <I>Os</I>Pex5pS in the <I>Atpex5</I> mutant, we show that <I>Os</I>Pex5pL translocates both PTS1- and PTS2-containing proteins into the peroxisome by interacting with <I>Os</I>Pex7p, whereas <I>Os</I>Pex5pS is involved only in PTS1-dependent import in Arabidopsis.</P>
Hurd, Matthew C.,Kwon, Moonhyuk,Ro, Dae-Kyun Elsevier 2017 Biochemical and biophysical research communication Vol.490 No.3
<P><B>Abstract</B></P> <P> <I>Lippia dulcis</I> (Aztec sweet herb) contains the potent natural sweetener hernandulcin, a sesquiterpene ketone found in the leaves and flowers. Utilizing the leaves for agricultural application is challenging due to the presence of the bitter-tasting and toxic monoterpene, camphor. To unlock the commercial potential of <I>L</I>. <I>dulcis</I> leaves, the first step of camphor biosynthesis by a bornyl diphosphate synthase needs to be elucidated. Two putative monoterpene synthases (<I>LdTPS3</I> and <I>LdTPS9</I>) were isolated from <I>L</I>. <I>dulcis</I> leaf cDNA. To elucidate their catalytic functions, <I>E. coli</I>-produced recombinant enzymes with truncations of their chloroplast transit peptides were assayed with geranyl diphosphate (GPP). <I>In vitro</I> enzyme assays showed that <I>LdTPS3</I> encodes bornyl diphosphate synthase (thus named <I>LdBPPS</I>) while <I>LdTPS9</I> encodes linalool synthase. Interestingly, the <I>N</I>-terminus of LdBPPS possesses two arginine-rich (RRX<SUB>8</SUB>W) motifs, and enzyme assays showed that the presence of both RRX<SUB>8</SUB>W motifs completely inhibits the catalytic activity of LdBPPS. Only after the removal of the putative chloroplast transit peptide and the first RRX<SUB>8</SUB>W, LdBPPS could react with GPP to produce bornyl diphosphate. LdBPPS is distantly related to the known bornyl diphosphate synthase from sage in a phylogenetic analysis, indicating a converged evolution of camphor biosynthesis in sage and <I>L. dulcis</I>. The discovery of LdBPPS opens up the possibility of engineering <I>L</I>. <I>dulcis</I> to remove the undesirable product, camphor.</P> <P><B>Highlights</B></P> <P> <UL> <LI> <I>Lippia dulcis</I> (Aztec herb) produces intensely sweet sesquiterpenoid, hernandulcin. </LI> <LI> A toxic terpene, camphor, is synthesized in <I>L. dulcis</I> alongside hernandulcin. </LI> <LI> Bornyl diphosphate synthase (BPPS) was first identified from <I>L. dulcis.</I> </LI> <LI> A repeat of arginine-rich motif inhibits <I>L. dulcis</I> BPPS activity. </LI> <LI> Sage and L. <I>dulcis</I> BPPS have independently evolved for the same catalytic activity. </LI> </UL> </P>
Characterization of a Piperonal Synthase in Pipper nigrum
Moonhyuk KWON,Zhehao JIN,Juraithip WUNGSINTAWEEKUL,Dae-Kyun RO,Seon-Won KIM,Soo-un KIM 한국생물공학회 2021 한국생물공학회 학술대회 Vol.2021 No.10
Piperonal with a characteristic cherry-like aroma is a simple aromatic aldehyde compound, which has been widely used in flavor and fragrance industries. The aldehyde is also a crucial aroma-imparting molecule of black pepper (Piper nigrum). The bioinformatic analysis of P. nigrum transcriptome data predicted a hydratase-lyase with conserved cysteine proteinases in excess of 68% identity. The hydratase-lyase catalyzed specific side-chain cleavage of 3,4-methylenedioxycinnamic acid (3,4-MDCA) to produce 3,4-methylenedioxybenzaldehyde (piperonal) in vitro and in the gene-harboring yeast. The enzyme was named 3,4-MDCA hydratase-lyase (PnMCHL) or piperonal synthase. However, purported substrates such as cinnamic, coumaric, caffeic, ferulic, and piperic acids did not generate corresponding cleavage products in transgenic yeast. The optimal pH for in-vitro PnMHL was 7.0, and it had Km value for 317.2 μM and kcat for 2.7 s<SUP>-1</SUP>. The enzyme was highly expressed in the leaves, followed by fruits.