http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Lim, He Kyoung,Chung, Eu Jin,Kim, Jin-Cheol,Choi, Gyung Ja,Jang, Kyoung Soo,Chung, Young Ryun,Cho, Kwang Yun,Lee, Seon-Woo American Society for Microbiology 2005 Applied and environmental microbiology Vol.71 No.12
<B>ABSTRACT</B><P>A microbial community analysis of forest soil from Jindong Valley, Korea, revealed that the most abundant rRNA genes were related to <I>Acidobacteria</I>, a major taxon with few cultured representatives. To access the microbial genetic resources of this forest soil, metagenomic libraries were constructed in fosmids, with an average DNA insert size of more than 35 kb. We constructed 80,500 clones from Yuseong and 33,200 clones from Jindong Valley forest soils. The double-agar-layer method allowed us to select two antibacterial clones by screening the constructed libraries using <I>Bacillus subtilis</I> as a target organism. Several clones produced purple or brown colonies. One of the selected antibacterial clones, pJEC5, produced purple colonies. Structural analysis of the purified pigments demonstrated that the metagenomic clone produced both the pigment indirubin and its isomer, indigo blue, resulting in purple colonies. In vitro mutational and subclonal analyses revealed that two open reading frames (ORFs) are responsible for the pigment production and antibacterial activity. The ORFs encode an oxygenase-like protein and a putative transcriptional regulator. Mutations of the gene encoding the oxygenase canceled both pigment production and antibacterial activity, whereas a subclone carrying the two ORFs retained pigment production and antibacterial activity. This finding suggests that these forest soil microbial genes are responsible for producing the pigment with antibacterial activity.</P>
Lim, He-Kyoung,Chung, Eu-Jin,Kim, Jin-Cheol,Choi, Gyung-Ja,Jang, Kyoung-Soo,Chung, Young-Ryun,Cho, Kwang-Yun,Lee, Seon-Woo Plant molecular biology and biotechnology research 2005 Plant molecular biology and biotechnology research Vol.2005 No.
A microbial community analysis of forest soil from Jindong Valley, Korea, revealed that the most abundant rRNA genes were related to Acidobacteria, a major taxon with few cultured representatives. To access the microbial genetic resources of this forest soil, metagenomic libraries were constructed in fosmids, with an average DNA insert size of more than 35 kb. We constructed 80,500 clones from Yuseong and 33,200 clones from Jindong Valley forest soils. The double-agar-layer method allowed us to select two antibacterial clones by screening the constructed libraries using Bacillus subtilis as a target organism. Several clones produced purple or brown colonies. One of the selected antibacterial clones, pJEC5, produced purple colonies. Structural analysis of the purified pigments demonstrated that the metagenomic clone produced both the pigment indirubin and its isomer, indigo blue, resulting in purple colonies. In vitro mutational and subclonal analyses revealed that two open reading frames (ORFs) are responsible for the pigment production and antibacterial activity. The ORFs encode an oxygenase-like protein and a putative transcriptional regulator. Mutations of the gene encoding the oxygenase canceled both pigment production and antibacterial activity, whereas a subclone carrying the two ORFs retained pigment production and antibacterial activity. This finding suggests that these forest soil microbial genes are responsible for producing the pigment with antibacterial activity.
A Clustering Scheme for Discovering Congested Routes on Road Networks
He Li,Kyoung Soo Bok,Jong Tae Lim,Byoung Yup Lee,Jae Soo Yoo 대한전기학회 2015 Journal of Electrical Engineering & Technology Vol.10 No.4
On road networks, the clustering of moving objects is important for traffic monitoring and routes recommendation. The existing schemes find out density route by considering the number of vehicles in a road segment. Since they don’t consider the features of each road segment such as width, length, and directions in a road network, the results are not correct in some real road networks. To overcome such problems, we propose a clustering method for congested routes discovering from the trajectories of moving objects on road networks. The proposed scheme can be divided into three steps. First, it divides each road network into segments with different width, length, and directions. Second, the congested road segments are detected through analyzing the trajectories of moving objects on the road network. The saturation degree of each road segment and the average moving speed of vehicles in a road segment are computed to detect the congested road segments. Finally, we compute the final congested routes by using a clustering scheme. The experimental results showed that the proposed scheme can efficiently discover the congested routes in different directions of the roads.
A Clustering Scheme for Discovering Congested Routes on Road Networks
Li, He,Bok, Kyoung Soo,Lim, Jong Tae,Lee, Byoung Yup,Yoo, Jae Soo The Korean Institute of Electrical Engineers 2015 Journal of Electrical Engineering & Technology Vol.10 No.4
On road networks, the clustering of moving objects is important for traffic monitoring and routes recommendation. The existing schemes find out density route by considering the number of vehicles in a road segment. Since they don’t consider the features of each road segment such as width, length, and directions in a road network, the results are not correct in some real road networks. To overcome such problems, we propose a clustering method for congested routes discovering from the trajectories of moving objects on road networks. The proposed scheme can be divided into three steps. First, it divides each road network into segments with different width, length, and directions. Second, the congested road segments are detected through analyzing the trajectories of moving objects on the road network. The saturation degree of each road segment and the average moving speed of vehicles in a road segment are computed to detect the congested road segments. Finally, we compute the final congested routes by using a clustering scheme. The experimental results showed that the proposed scheme can efficiently discover the congested routes in different directions of the roads.
Selection and Characterization of Forest Soil Metagenome Genes Encoding Lipolytic Enzymes
( Kyung Sik Hong ),( He Kyoung Lim ),( Eu Jin Chung ),( Eun Jin Park ),( Myung Hwan Lee ),( Jin Cheol Kim ),( Gyung Ja Choi ),( Kwang Yun Cho ),( Seon Woo Lee ) 한국미생물생명공학회 2007 Journal of microbiology and biotechnology Vol.17 No.10
Production of porphyrin intermediates in<i>Escherichia coli</i>carrying soil metagenomic genes
Kim, Jin-Seog,Lim, He Kyoung,Lee, Myung Hwan,Park, Ji-Hye,Hwang, Eul Chul,Moon, Byung Ju,Lee, Seon-Woo Oxford University Press 2009 FEMS microbiology letters Vol.295 No.1
<P>Tetrapyrrole pigments are important components of many biological processes, and many of them are produced primarily by microorganisms. We constructed a soil metagenomic library using rice paddy soil consisting of 107 000 fosmid clones with an average DNA insert size of 35 kb. We isolated a clone carrying genes in the porphyrin biosynthetic pathway based on function-driven screening of the library. Through subcloning and mutagenesis analysis, we showed that two genes from soil metagenome, gtrA and hemC, were responsible for pigmentation in Escherichia coli. HPLC and LC-MS analysis of the purified pigments from E. coli carrying pSY143 identified coproporphyrin III without metal as a major compound as well as some other minor porphyrin intermediates. As gtrA and hemC encode glutamyl-tRNA reductase and porphobilinogen deaminase, respectively, which are enzymes involved in the C5 biosynthetic pathway for porphyrin intermediates, our results suggest that hemL, hemB, hemD, and hemE should be provided by the E. coli chromosome to generate a hybrid biosynthetic pathway for production of porphyrin intermediates using E. coli and metagenomic genes.</P>
Forest Soil Metagenome Gene Cluster Involved in Antifungal Activity Expression in Escherichia coli
Chung, Eu Jin,Lim, He Kyoung,Kim, Jin-Cheol,Choi, Gyung Ja,Park, Eun Jin,Lee, Myung Hwan,Chung, Young Ryun,Lee, Seon-Woo American Society for Microbiology 2008 Applied and environmental microbiology Vol.74 No.3
<B>ABSTRACT</B><P>Using two forest soils, we previously constructed two fosmid libraries containing 113,700 members in total. The libraries were screened to select active antifungal clones using <I>Saccharomyces cerevisiae</I> as a target fungus. One clone from the Yuseong pine tree rhizosphere soil library, pEAF66, showed <I>S. cerevisiae</I> growth inhibition. Despite an intensive effort, active chemicals were not isolated. DNA sequence analysis and transposon mutagenesis of pEAF66 revealed 39 open reading frames (ORFs) and indicated that eight ORFs, probably in one transcriptional unit, might be directly involved in the expression of antifungal activity in <I>Escherichia coli</I>. The deduced amino acid sequences of eight ORFs were similar to those of the core genes encoding type II family polyketide synthases, such as the acyl carrier protein (ACP), ACP synthases, aminotransferase, and ACP reductase. The gene cluster involved in antifungal activity was similar in organization to the putative antibiotic production locus of <I>Pseudomonas putida</I> KT2440, although we could not select a similar active clone from the KT2440 genomic DNA library in <I>E. coli</I>. ORFs encoding ATP binding cassette transporters and membrane proteins were located at both ends of the antifungal gene cluster. Upstream ORFs encoding an IclR family response regulator and a LysR family response regulator were involved in the positive regulation of antifungal gene expression. Our results suggested the metagenomic approach as an alternative to search for novel antifungal antibiotics from unculturable soil bacteria. This is the first report of an antifungal gene cluster obtained from a soil metagenome using <I>S. cerevisiae</I> as a target fungus.</P>