833 results match your criteria: "School of Agricultural Biotechnology[Affiliation]"
Biochem Biophys Res Commun
May 2007
School of Agricultural Biotechnology, Seoul National University, Seoul 151-921, Republic of Korea.
It has long been recognized that leptin, a hormone made by adipocytes, is an important circulating signal for the regulation of body weight. In addition, matrix metalloproteinase (MMP), especially MMP-2, an adipocyte-secreted protein which promotes multi-cellular adipose clusters, is up-regulated in obesity. The present study is designed to evaluate whether trans-10,cis-12 conjugated linoleic acid (t-CLA) can suppress leptin-induced MMP-2 secretion in 3T3-L1 cells.
View Article and Find Full Text PDFChem Biol Interact
April 2007
School of Agricultural Biotechnology, Seoul National University, Seoul 151-921, South Korea.
Green tea catechins (GTCs) are polyphenolic flavonoids formerly called vitamin P. GTCs, especially (-)-epigallocatechin-3-gallate (EGCG), lower the incidence of cancers, collagen-induced arthritis, oxidative stress-induced neurodegenerative diseases, and streptozotocin-induced diabetes. Also, inhibition of adipogenesis by green tea and green tea extract has been demonstrated in cell lines, animal models, and humans.
View Article and Find Full Text PDFPlant Mol Biol
May 2007
School of Agricultural Biotechnology, Seoul National University, Seoul 151-742, Korea.
We cloned a salicylic acid/benzoic acid carboxyl methyltransferase gene, OsBSMT1, from Oryza sativa. A recombinant OsBSMT1 protein obtained by expressing the gene in Escherichia coli exhibited carboxyl methyltransferase activity in reactions with salicylic acid (SA), benzoic acid (BA), and de-S-methyl benzo(1,2,3)thiadiazole-7-carbothioic acid (dSM-BTH), producing methyl salicylate (MeSA), methyl benzoate (MeBA), and methyl dSM-BTH (MeBTH), respectively. Compared to wild-type plants, transgenic Arabidopsis overexpressing OsBSMT1 accumulated considerably higher levels of MeSA and MeBA, some of which were vaporized into the environment.
View Article and Find Full Text PDFNucleic Acids Res
May 2007
Department of Food and Animal Biotechnology, School of Agricultural Biotechnology, and Center for Agricultural Biomaterials, Seoul National University, Seoul 151-921, Republic of Korea.
The global regulator Mlc is a repressor of several genes and operons that are involved in sugar uptake and metabolism. A Salmonella enterica serovar Typhimurium mlc mutant showed reduced levels of invasion and cytotoxicity compared to the wild-type, and exhibited reduced expression levels of hilD, hilA and invF, which are regulatory genes in the Salmonella pathogenicity island 1 (SPI1). However, the effects of Mlc on hilD expression and bacterial invasiveness were not seen in the hilE mutant, and hilE expression was increased in the mlc mutant, which suggests that Mlc exerts positive effects on the expression of SPI1 genes by reducing the expression of HilE, which is known to down-regulate the expression of SPI1 genes through direct interaction with HilD.
View Article and Find Full Text PDFJ Nematol
March 2007
School of Agricultural Biotechnology, Seoul National University, Seoul 151-921, Republic of Korea Southern Forest Research Institute, Korea Forest Research Institute, Jinju 660-300, Republic of Korea.
The nematicidal activity of two cassia, Cinnamomum cassia, oils (Especial and true), four cinnamon, Cinnamomum zey-lanicum, oils (technical, #500, bark and green leaf), and their compounds (e.g., trans-cinnamaldehyde and trans-cinnamic acid) toward adult Bursaphelenchus xylophilus was examined by a direct contact bioassay.
View Article and Find Full Text PDFVet Microbiol
June 2007
Department of Microbiology, College of Veterinary Medicine and School of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea.
The purpose of this study was to investigate the genetic similarity of Campylobacter jejuni and Campylobacter coli with similar antimicrobial resistance phenotypes, isolated from cattle on different farms and at different times, in order to evaluate the possible existence of disseminated antimicrobial resistant clones. PFGE after SmaI and KpnI restriction identified 23 and 16 distinct PFGE patterns among 29 C. jejuni and 66 C.
View Article and Find Full Text PDFExtremophiles
May 2007
Center for Agricultural Biomaterials, and Department of Food Science and Biotechnology, School of Agricultural Biotechnology, Seoul National University, Seoul, 151-921, South Korea.
A gene that encodes the enzyme Pyrococcus furiosus cyclodextrin glucanotransferase (PFCGT) was cloned in Escherichia coli. PFCGT was highly expressed in recombinant E. coli after compensation for codon usage bias using the pRARE plasmid.
View Article and Find Full Text PDFMol Microbiol
February 2007
School of Agricultural Biotechnology and Center for Agricultural Biomaterials, Seoul National University, Seoul 151-921, Korea.
Gibberella zeae is an ascomyceteous fungus that causes serious diseases in cereal crops. Severe epidemics require strains that are virulent and that can reproduce sexually. We characterized an insertional mutant (designated ZH436) with a pleiotropic defect in both traits, and identified a novel F-box protein gene encoding FBP1 (F-box protein 1) that is similar to fungal F-box proteins including Saccharomyces cerevisiae Grr1, a well-characterized component of the Skp1-Cullin-F-box protein (SCF(Grr1)) E3 ligase complex required for protein degradation.
View Article and Find Full Text PDFPlant Cell Rep
July 2007
School of Agricultural Biotechnology and Center for Agricultural Biomaterials, Seoul National University, Seoul 151-921, Korea.
Jasmonates comprise a family of plant hormones that regulate gene expression to modulate diverse developmental and defensive processes. To screen a set of jasmonate-responsive Arabidopsis genes, we performed a microarray analysis using an Affymetrix GeneChip containing about 8,300 gene probes synthesized in situ. External treatment with 100 microM methyl jasmonate resulted in significant changes (more than twofold increases or decreases) in the expression levels of 137 genes in the rosette leaves of 5-week-old Arabidopsis plants.
View Article and Find Full Text PDFVet Parasitol
April 2007
School of Agricultural Biotechnology, Seoul National University, Seoul 151-921, Republic of Korea.
The acaricidal activity of methanolic extracts from 40 oriental medicinal plant species and a steam distillate of Cinnamomum camphora towards poultry house-collected adult Dermanyssus gallinae De Geer was examined using direct contact and vapour phase toxicity bioassays. Results were compared with those of 15 acaricides currently used. In filter paper contact toxicity bioassays using adult D.
View Article and Find Full Text PDFJ Biol Chem
March 2007
Molecular Signaling Laboratory, Department of Chemistry, Seoul National University, Seoul 151-742, Korea. Electronic address:
Plants constantly monitor environmental fluctuations to optimize their growth and metabolism. One example is adaptive growth occurring in response to biotic and abiotic stresses. Here, we demonstrate that GH3-mediated auxin homeostasis is an essential constituent of the complex network of auxin actions that regulates stress adaptation responses in Arabidopsis.
View Article and Find Full Text PDFJ Biochem Mol Biol
January 2007
Laboratory of Bioinformatics and Population Genetics, School of Agricultural Biotechnology, Seoul National University, Seoul 151-742, Korea.
Bovine coding region single nucleotide polymorphisms located proximal to quantitative trait loci were identified to facilitate bovine QTL fine mapping research. A total of 692,763 bovine SNPs was extracted from 39,432 UniGene clusters, and 53,446 candidate SNPs were found to be a depth >3. In order to validate the in silico SNPs experimentally, 186 animals representing 14 breeds and 100 mixed breeds were analyzed.
View Article and Find Full Text PDFInt J Food Microbiol
February 2007
Department of Food and Animal Biotechnology, School of Agricultural Biotechnology and Center for Agricultural Biomaterials, Seoul National University, San 56-1, Shillim-dong, Kwanak-gu, Seoul 151-742, Republic of Korea.
Campylobacter jejuni is a frequently detected food-borne pathogenic bacterium. Clinical cases are mostly sporadic but campylobacteriosis can have serious consequences, such as the development of Guillain-Barré syndrome as well as diarrheal diseases. We examined 265 retail raw chickens from Korean markets for the presence of C.
View Article and Find Full Text PDFJ Control Release
February 2007
School of Agricultural Biotechnology, Seoul National University, Seoul, South Korea.
Chitosans have been proposed as biocompatible alternative cationic polymers that are suitable for non-viral delivery. However, the transfection efficiency of chitosan-DNA nanoparticles is still very low. To improve transfection efficiency, we prepared chitosan-graft-polyethylenimine (CHI-g-PEI) copolymer by an imine reaction between periodate-oxidized chitosan and polyethylenimine (PEI).
View Article and Find Full Text PDFCurr Genet
February 2007
School of Agricultural Biotechnology and Center for Agricultural Biomaterials, Seoul National University, Seoul, 151-921, South Korea.
Gibberella zeae (anamorph, Fusarium graminearum) is an important pathogen of cereal crops found in many regions of the world. In this study, we have characterized two auxotrophic strains, designated S4B1279 and S4B3008, which were discovered from a collection of insertional mutants of G. zeae generated by restriction enzyme-mediated integration (REMI).
View Article and Find Full Text PDFArch Microbiol
February 2007
School of Agricultural Biotechnology, Seoul National University, Seoul 151-742, South Korea.
An anaerobic incubation mixture of two bacterial strains Eggerthella sp. Julong 732 and Lactobacillus sp. Niu-O16, which have been known to transform dihydrodaidzein to S-equol and daidzein to dihydrodaidzein respectively, produced S-equol from daidzein through dihydrodaidzein.
View Article and Find Full Text PDFExp Anim
October 2006
Department of Laboratory Animal Medicine, College of Veterinary Medicine and School of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea.
In this study, microbiological monitoring of guinea pigs reared conventionally in two facilities was performed twice in 2004, with a three-month-interval between surveys. This study was based on the recommendations of the FELASA Working Group, with some modifications. In serological tests in the first survey, some animals from facility A showed positive results for Encephalitozoon cuniculi, Sendai virus, pneumonia virus of mice (PVM), and Reovirus-3 (Reo-3); facility B showed a positive result only for E.
View Article and Find Full Text PDFBiosci Biotechnol Biochem
November 2006
Department of Animal Science, School of Agricultural Biotechnology, Seoul National University, Seoul, Korea.
The effects were observed of feeding a high-temperature-micro-time (HTMT)-treated diet of high-quality extruded soybean (ESB) on trans-10, cis-12 conjugated linoleic acid (CLA) incorporation in intra-muscular fat and on the lipid metabolism of twelve Holstein steers. The animals were randomly allocated to three groups, the control group being fed on a normal diet, and the other two groups being fed on a diet containing high-quality ESB with or without the HTMT treatment. The experimental period was four months.
View Article and Find Full Text PDFArch Biochem Biophys
December 2006
School of Agricultural Biotechnology, Seoul National University, Seoul 151-921, South Korea.
This study is designed to evaluate whether the PEGylated conjugated linoleic acid (PCLA) as the pro-drug can have favorable stability, bioavailability, and anti-adipogenic activity in 3T3-L1 cells for anti-obesity when compared with conjugated linoleic acid (CLA) itself. The CLA was simply coupled to poly(ethylene glycol) (PEG) at the melting state without solvents or catalysts through ester linkages between the carboxylic group of CLA and the hydroxyl group of PEG. To confirm of PCLA as the pro-drug, CLA release from PCLA was investigated by using high-performance liquid chromatographic (HPLC), showing that CLA release from PCLA was almost 90% in a nearly continuous fashion over the next 75h.
View Article and Find Full Text PDFJ Econ Entomol
October 2006
School of Agricultural Biotechnology, Seoul National University, Seoul 151-921, Republic of Korea.
The fumigant toxicity of 92 plant essential oils to adult Thrips palmi Karny (Thysanoptera: Thripidae) and Orius strigicollis Poppius (Heteroptera: Anthocoridae) was examined by using a vapor phase toxicity bioassay and compared with those of dichlorvos, emamectin benzoate, spinosad, and thiamethoxam, four commonly used insecticides. Responses varied according to oil type and insect species. As judged by 24-h LC50 values, pennyroyal oil (2.
View Article and Find Full Text PDFJ Nanosci Nanotechnol
December 2006
School of Agricultural Biotechnology, Seoul National University, Seoul 151-921, Korea.
Dendritic cells (DCs) are professional antigen presenting cells that induce, sustain, and regulate immune responses. Gene modification of DCs is of particular interest for immunotherapy of diseases where the immunes system has failed or is abnormally regulated, such as in cancer or autoimmune disease. Gene transfer using non-viral vectors is a promising approach for the safe delivery of therapeutic DNA.
View Article and Find Full Text PDFBiochim Biophys Acta
October 2006
Center for Agricultural Biomaterials and Department of Food Science and Biotechnology, School of Agricultural Biotechnology, Seoul National University, Seoul 151-742, Korea.
A W229H mutant of 4-alpha-glucanotransferase (4-alpha-GTase) from Pyrococcus furiosus was constructed and its catalytic properties were studied to investigate the role of W229 in the catalytic specificities of the enzyme. Various activities and kinetic parameters were determined for the wild-type and W229H mutant enzymes. The transglycosylation factor and transglycosylation activity of the mutant enzyme markedly decreased, but its hydrolysis activity was scarcely affected.
View Article and Find Full Text PDFBiomaterials
February 2007
School of Agricultural Biotechnology, Seoul National University, Seoul 151-921, South Korea.
The aim of research was to develop and optimize delivery systems for plasmid DNA (pDNA) based on biodegradable polymers, in particular, poly(ester amine)s (PEAs), suitable for non-viral gene therapy. Poly(ester amine)s were successfully synthesized by Michael addition reaction between polycaprolactone (PCL) diacrylate and low molecular weight polyethylenimine (PEI). PEA/DNA complexes showed effective and stable DNA condensation with the particle sizes below 200nm, implicating its potential for intracellular delivery.
View Article and Find Full Text PDFJ Food Prot
September 2006
School of Agricultural Biotechnology and Center for Agricultural Biomaterials, Seoul National University, San 56-1, Sillim-dong, Gwanak-gu, Seoul 151-921, Korea.
To control the spread of bovine spongiform encephalopathy in cattle through contaminated animal feedstuffs, screening of feed products is essential. We designed five pairs of primers to identify specifically raw and heat-treated tissue from cattle, sheep, goat, deer, and ruminants in general. A forward common primer was designed based on a conserved DNA sequence in the mitochondrial 12S rRNA-tRNA(val)-16S rRNA gene, and reverse primers were designed to hybridize with a species-specific DNA sequence for each species considered.
View Article and Find Full Text PDFVet Pathol
September 2006
Department of Veterinary Pathology, College of Veterinary Medicine and School of Agricultural Biotechnology, Seoul National University, Seoul, Kwanak-Gu, Republic of Korea.
This study investigated the potentiation of porcine circovirus 2 (PCV2)-induced postweaning multisystemic wasting syndrome by porcine parvovirus (PPV) and found it was associated with excessive production of tumor necrosis factor-alpha (TNF-alpha). Colostrum-deprived conventional pigs were inoculated intranasally with PCV2 or PPV alone or in combination (PCV2 and PPV). In vitro assay of TNF-alpha, obtained from alveolar macrophages coinfected with PCV2 and PPV, showed a significant increase in TNF-alpha compared to single infection of macrophages with either PCV2 or PPV alone (P < 0.
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