• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2627-2632
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• 2010

Hormone sensitive lipase (HSL) plays a major role in energy homeostasis and lipid metabolism. Several crystal structures of HSL-homolog proteins have been identified, which has led to a better understanding of its molecular function. HSL-homolog proteins exit as both monomer and dimer, but the biochemical and structural basis for such oligomeric states has not been successfully elucidated. Therefore, we determined the crystal structure of HSL-homolog protein EstE7 from a metagenome library at $2.2\;{\AA}$ resolution and characterized the oligomeric states of EstE7 both structurally and biochemically. EstE7 protein prefers the dimeric state in solution, which is supported by its higher enzymatic activity in the dimeric state. In the crystal form, EstE7 protein shows two-types of dimeric interface. Specifically, dimerization via the external ${beta}8$-strand occurred through tight association between two pseudosymmetric folds via salt bridges, hydrogen bonds and van der Waals interactions. This dimer formation was similar to that of other HSL-homolog protein structures such as AFEST, BEFA, and EstE1. We anticipate that our results will provide insight into the oligomeric state of HSL-homolog proteins.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5B
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• pp.459-473
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• 2008

This study investigated typhoon characteristics that provoke precipitation which is much attacking periodically in our country, and calculated probability precipitation of extreme rainfalls using Empirical Simulation Technique. The typhoon influenced in Korea was happened 3.18 times per, and year exposed to affect Korea during 107 hours. The depth of precipitation with the typhoon was different according to observation points. The extreme precipitation of typhoon events has analyzed by change and trend analyses. In the results, mean and standard deviation of extreme rainfall has been increasing than the past events in some areas. Also, About 143 typhoons influenced Korea was applied in EST techniques using center position, central pressure, time precipitation data using rainfall observatory in Korea. Therefore, we applied EST techniques and calculated probability precipitation. In the results, Jeonla-do, Gyeongsang-do and Gangwon-do will have heavy rain with typhoon events in high probability.

• Proceedings of the Korean Information Science Society Conference
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• 2002.10d
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• pp.634-636
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• 2002

산업분야에서 자동화 시스템은 자동설계, 생산설비의 관리, 품질검사 등 각종 생산과 관련되어 모든 일을 자동으로 처리 할 수 있도록 하여 생산성을 향상시킨다. 일반적으로 자동화 시스템에서 사용되는 소프트웨어는 사용할 수 있는 흐름 제어 언어가 2종류 이하로 제한이 되어 있고, 동일한 시스템에서 언어의 혼용을 통한 시뮬레이션이 불가능하다. 이에 본 논문에서 혼용 사용이 가능한 흐름 제어 언어 통합 분석기를 제시한다. 고급언어 형태의 ST를 기초로 확장한 언어인 EST를 제시하고 통합 분석기를 위하여 그래픽언어를 EST로 변환하고 흐름제어 규칙 작성이 가능한 FBD 편집기, FBD 편집기에서 출력한 EST를 다시 변환하는 EST-IL 변환기를 설계 및 구현한다. EST를 기준으로 그래픽 언어를 통합하는 통합 분석기는 흐름 제어 언어의 통합 시뮬레이션이 가능하다.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.04b
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• pp.1013-1016
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• 2002

제어 시스템에 사용되는 흐름 제어 언어로는 IL(Instruction List), ST(Structured Text), FBD(Function Block Diagram), SFC(Sequential Function Chart), LD (Ladder Diagram)가 있다. 일반적으로 제어 시스템에 탑재하여 사용하는 언어는 상기 언어 중 두 종류 이하의 특정 언어로 제한되어 있다. 이러한 제약을 보완하기 위해, 모든 흐름 제어 언어를 통합 분석할 수 있는 통합 분석기가 필요하다. 본 논문에서는 흐름 제어 언어의 통합 분석 처리가 가능하도록 그래픽 표현의 FBD 를 문자 표현의 EST(Extended Structured Text)로 변형하는 규칙과 문자 표현의 EST 를 IL 로 변형하는 규칙을 제시한다. 언어간의 변형 과정에서 FBD 를 ST 로 표현할 수 없는 부분을 EST 로 정의한다. 또한 본 논문에서 제안된 EST 를 기반으로 통합 분석기의 구조를 제시한다.

• Journal of Microbiology and Biotechnology
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• v.22 no.8
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• pp.1044-1053
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• 2012

The gene encoding an esterase enzyme was cloned from a metagenomic library of cow rumen bacteria. The esterase gene (est5S) was 1,026 bp in length, encoding a protein of 366 amino acid residues with a calculated molecular mass of 40,168 Da. The molecular mass of the enzyme was estimated to be 40,000 Da. The Est5S protein contains the Gly-X-Ser-X-Gly motif found in most bacterial and eukaryotic serine hydrolases. However, the Asp or Glu necessary for the catalytic triad [Ser-Asp-(Glu)-His] was not present, indicating Est5S represents a novel member of the GHSQG family of esterolytic enzymes. BlastP in the NCBI database analysis of Est5S revealed homology to hypothetical proteins and it had no homology to previous known lipases and esterases. Est5S was optimally active at pH 7.0 and $40^{\circ}C$. Among the p-nitrophenyl acylesters tested, high enzymatic activities were observed on the short-chain p-nitrophenyl acylesters, such as p-nitrophenyl acetate, etc. The conserved serine residue ($Ser_{190}$) was shown to be important for Est5S activity. The primers that amplified the est5S gene did not show any relative band with 49 species of culturable rumen bacteria. This implies that a new group esterase gene, est5S, may have come from a noncultured cow rumen bacterium.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.74-74
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• 2018

Little millet (Panicum sumatrense) is well known for its salt and drought stress tolerance and high nutritional value, but very limited knowledge of genetic variation and genomic information is available. This study was to develop highly polymorphic EST-SSR markers based on cross-species transferability of derived SSRs from switchgrass EST databases and characterize newly developed EST - SSRs to better understand the genetic diversity of collected 37 germplasm accessions of little millet. A total of 779 primer pairs were designed from the 22,961 EST sequences of switchgrass (Pancium virgatum), of which 48 EST - SSR markers were developed based on the trials of transferability of these primers in little millet. The EST - SSR amplicons showed reproducible single band polymorphism and produced a total of 160 alleles with an average of 3.3 alleles per locus in 37 accessions of little millet. T he average values of expected and observed heterozygosities were 0.266 and 0.123, respectively. T he polymorphic information content (PIC) values were observed in range of 0.026 to 0.549 with an average of 0.240. The genetic relatedness among the little millet accessions was evaluated by neighbor-joining dendrogram, which grouped all accessions into two distinct groups. The validation thus demonstrated the utility of the switchgrass EST - SSR markers in assessing genomic relationships in little millet. T he findings from this study could be useful for designing strategies for the identification of diverse germplasm for conservation and future molecular breeding programs for little millet.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.43-43
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• 2019

The collection, evaluation and conservation of crop germplasm have been treated as one of the basics to breeding program. An understanding of genetic relationships among germplasm resources is vital for future breeding process like yield, quality, and resistance. In the present study, EST-SSR markers were employed to assess the polymorphism and genetic diversity of 192 accessions of Proso millet preserved in the National Agrobiodiversity Center of RDA. We evaluated the efficiency of EST-SSR markers developed for proso millet species. A total of 98 alleles were detected with an average allele number of 4.5 per locus among 192 proso millet millet accessions using 22 EST-SSR markers. The averaged values of gene diversity ($H_E$) and polymorphism information content (PIC) for each EST-SSR marker were 0.362 and 0.404 within populations, respectively. Our results showed the moderate level of the molecular diversity among the proso millet accessions from diverse countries. A phylogenetic tree revealed three major groups of accessions that did not correspond with geographical distribution patterns with a few exceptions. The less correlation between the clusters and their geographic location might be considered due to their type difference. Our study provided a better understanding of genetic relationships among various germplasm collections, and it could contribute to more efficient utilization of valuable genetic resources. The EST-SSR markers developed here will serve as a valuable resource for genetic studies, like linkage mapping, diversity analysis, quantitative trait locus/association mapping, and molecular breeding.

• Korean Journal of Ichthyology
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• v.19 no.4
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• pp.257-265
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• 2007

We constructed a cDNA library of testis from olive flounder (Paralichthys olivaceus) and a total of 248 expressed sequence tag (EST) clones were generated. In order to understand the molecular compositions of the olive flounder testis organs, the expression profiles of the identified clones in the cDNA library were analyzed. Gene annotation procedures and homology searches of the sequenced ESTs were locally done by BLASTX for amino acid similarity comparisons. Of the 248 EST clones, 156 ESTs showed significant homology to previously described genes while 92 ESTs were unidentified or novel. Comparative analysis of the 156 identified ESTs showed that 6 (3.8%) clones were representing 5 unique genes identified as homologous to the previously reported olive flounder ESTs, 100 (64.1%) clones representing 94 unique genes were identified as orthologs of known genes from other organisms, and orthologs were established for 50 (32.1%) clones representing 44 genes of known sequences with unknown functions. Furthermore, the testis library showed a more even distribution of cDNA clones with relatively fewer abundant clones that tend to contribute redundant clones in EST projects; thus, the testis library can supply more unique and novel cDNA sequences in olive flounder EST project.

• Journal of Korea Society of Digital Industry and Information Management
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• v.7 no.2
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• pp.115-125
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• 2011

An accurate estimation of software development size is an important factor in calculating reasonable cost of project development and determining its success. In this study, we propose estimation models, using function point based on the functional correlation between software, with empirical data. Three models($FP_{est}(I)$, $FP_{est}(II)$, $FP_{est}(III)$) are developed with correlation and regression analysis. The validity of the models is evaluated by the significance test by comparing values of Mean Magnitude of Relative Error (MMRE) and predictions of each model at level n%. Model $FP_{est}(III)$ proved to be superior to other models such as IFPC(Indicative Function Point Count), EFPC(Estimated Function Point Count), EPFS(Early Prediction of Function Size), $FP_{est}(I)$, and $FP_{est}(II)$. As a result, the accuracy of the model appears to be very high to determine the usefulness of the model to finally overcome weakness of other estimation models. The model can be efficiently used to estimate project development size including software size or manpower allocation.

• Journal of Microbiology and Biotechnology
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• v.26 no.2
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• pp.315-325
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• 2016

A novel esterase gene, est7K, was isolated from a compost metagenomic library. The gene encoded a protein of 411 amino acids and the molecular mass of the Est7K was estimated to be 44,969 Da with no signal peptide. Est7K showed the highest identity of 57% to EstA3, which is an esterase from a drinking water metagenome, when compared with the enzymes with reported properties. Est7K had three motifs, SMTK, YSV, and WGG, which correspond to the typical motifs of family VIII esterases, SxxK, Yxx, and WGG, respectively. Est7K did not have the GxSxG motif in most lipolytic enzymes. Three additional motifs, LxxxPGxxW, PLGMxDTxF, and GGxG, were found to be conserved in family VIII enzymes. The results of the phylogenetic analysis and the alignment study suggest that family VIII enzymes could be classified into two subfamilies, VIII.1 and VIII.2. The purified Est7K was optimally active at 40ºC and pH 10.0. It was activated to exhibit a 2.1-fold higher activity by the presence of 30% methanol. It preferred short-length p-nitrophenyl esters, particularly p-nitrophenyl butyrate, and efficiently hydrolyzed glyceryl tributyrate. It did not hydrolyze β-lactamase substrates, tertiary alcohol esters, glyceryl trioleate, fish oil, and olive oil. Est7K preferred an S-enantiomer, such as (S)-methyl-3-hydroxy-2-methylpropionate, as the substrate. The tolerance to methanol and the substrate specificity may provide potential advantage in the use of the enzyme in pharmaceutical and other biotechnological processes.