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81.
Kim YG  Kim SY  Hur YM  Joo HS  Chung J  Lee DS  Royle L  Rudd PM  Dwek RA  Harvey DJ  Kim BG 《Proteomics》2006,6(4):1133-1142
The immunogenic nonhuman carbohydrate sequences in membrane proteins from porcine kidney were identified and characterized using MALDI-TOF MS and ESI-QTOF-MS. The MALDI profile, investigated by incubation with exoglycosidases, showed a series of about 40 carbohydrates that were identified as high mannose glycans (Man(3-9)GlcNAc2) and complex bi-, tri-, and tetra-antennary glycans with and without core fucose. The antennae of many of the complex glycans were terminated with alpha-galactose residues, with the numbers of these residues ranging from one up to the number of antennae. Negative ion ESI-MS/MS spectra confirmed the location of the alpha-galactose residues on the ends of the antennae. This total glycan profile of the membrane proteins from porcine kidney will thus provide important information for the study of molecular interactions between antigenic carbohydrates and proteins in xenotransplantation.  相似文献   
82.
Background, Aims and Scope Telecommunication and information technology, dramatically emerged during the last decade, has generated environmental problems by accelerating mass production, mass consumption, and mass disposal of personal computers (PCs) in Korea. In addition, it has led the Korean new economy. The Korean government has encouraged researchers and industry to study the environmental impact, adequate disposal treatment, and the reasonable recycling rate of an end-of-life personal computer. The main purpose of this research is to investigate the life cycle environmental impact of PCs and to determine the desirable or feasible recycle rate of an end-of-life PC. An LCA on a PC was performed based on different recycling scenario. Target audiences are new product developers, designers, product recovery managers and environmental policy makers who are interested in the environmental impact of PCs and recycling of end-of-life products. Methods A target product is a Pentium IV personal computer made in Korea in 2001, excluding the monitor and peripheral equipment. The procedure of the LCA followed the ISO14040 series. System boundary includes the entire life cycle of the product, including pre-manufacturing (the electrical parts and components manufacturing), manufacturing, transportation, use, and disposal. The LCI and impact assessment database for a PC was constructed using SIMAPRO version 4.0 software and LCI information was compiled by site-specific data and the Korean national database. The LCA was performed on different recycling scenarios: one being that of the current recycling rate of 46%, and the other being the ideal condition of a 100% recycling rate. Results and Discussion Abiotic depletion, global warming, ecotoxicity, human toxicity, acidification, ozone layer depletion, photo-oxidant formation, and eutrophication are adopted as the impact categories. The pre-manufacturing stage was a significant stage for all of the environmental parameters, besides human toxicity potential. PC manufacturing consists of rather simple processes such as assembly and packaging. For improving the environmental performance of PCs, environmental management approaches of design for the environment and green procurement are recommended. The use stage had a significant potential due to the electricity consumption produced by burning fossil fuel. The disposal stage's contribution to environmental impact was largest in human toxicity, and second largest in ozone layer depletion potential. The PC recycling was shown to inhibit all environmental impacts with the exception of the ozone depletion and ecotoxicity potential. The increase of light oil, nitric acid, sulfuric acid, and deoxidating agent consumption during the recycling process contributes to the environmental impact of ozone and ecotoxicity parameters. Current recovery and recycling technologies should be taken into account for enhancing the benefits of recycling. Anyway, the effectiveness of recycling was highlighted by this study. PC recycling reduces the total environmental impact of the product. The PC recycling is recommended to be raised up to at least 63% in order to reduce the environmental burdens of a PC in other life cycle stages. Conclusion and Recommendation This study implies that design for the environment (DfE) in the product design stage and green procurement are recommended for improving the entire environmental performance of electronic equipment such as PCs. The recycling of waste PCs clearly reduces the environmental burden. There are, however, trade-offs among environmental parameters according to the PC recycling rate. Current recycling methods are not effective in reducing ozone depletion and ecotoxicity environmental impact. The product recovery is another key for efficient recycling. Efficient reverse logistics to collect and transport end-of-life PCs should be taken into account to enhance recycling effects. There were several electrical parts not included in this assessment, due to the unavailability of adequate data. Further studies with more detail and reliable inventories for electrical parts and sub-components are recommended. Furthermore, costs of recycling should also be treated in further research.  相似文献   
83.
Shewanella oneidensis MR-1 has the ability to inhale certain metals and chemical compounds and exhale these materials in an altered state; as a result, this microorganism has been widely applied in bioremediation protocols. However, the relevant characteristics of cell growth and biosynthesis of PuFAs have yet to be thoroughly investigated. Therefore, in this study, we have attempted to characterize the growth and fatty acid profiles ofS. oneidensis MR-1 under a variety of temperature conditions. The fastest growth ofS. oneidensis MR-1 was observed at 30°C, with a specific growth rate and doubling time of 0.6885 h−1 and 1.007 h. The maximum cell mass of this microorganism was elicited at a temperature of 4°C. The eicosapentaenoic acid (EPA) synthesis ofS. oneidensis MR-1 was evaluated under these different culture temperatures.S. oneidensis MR-1 was found not to synthesize EPA at temperatures in excess of 30°C, but was shown to synthesize EPA at temperatures below 30°C. The EPA content was found to increase with decreases in temperature. We then evaluated the EPA biosynthetic pathway, using a phylogenetic tree predicted on 16s rRNA sequences, and the homology of ORFs betweenS. oneidensis MR-1 andShewanella putrefaciens SCRC-2738, which is known to harbor a polyketide synthase (PKS)-like module. The phylogenetic tree revealed that MR-1 was very closely related to bothMoritella sp., which is known to synthesize DHA via a PKS-like pathway, andS. putrefaciens, which has been reported to synthesize EPA via an identical pathway. The homology between the PKS-like module ofS. putrefaciens SCRC-2738 and the entire genome ofS. oneidensis MR-1 was also analyzed, in order to mine the genes associated with the PKS-like pathway inS. oneidensis MR-1. A putative PKS-like module for EPA biosynthesis was verified by this analysis, and was also corroborated by the experimental finding thatS. oneidensis MR-1 was able to synthesize EPA without the expression of dihomo-γ-linoleic acid (DGLA) and arachidonic acid (AA) formed during EPA synthesis via the FAS pathway.  相似文献   
84.
Regioselectivity of 7-O-methyltransferase of poplar to flavones   总被引:1,自引:0,他引:1  
POMT-7, an O-methyltransferase from poplar (Populus deltoids) was used to modify a variety of flavonoid compounds. POMT-7 was able to transfer a methyl group to several flavonoids containing a C-7 hydroxyl group. However, POMT-7 showed a higher affinity toward flavonol and flavone such as apigenin, kaempferol, luteolin, and quercetin than flavanone and isoflavone. Based on comparison of HPLC retention times with authentic compounds and corresponding nuclear magnetic resonance spectroscopy data, the methylation position of the reaction products was determined to be at the hydroxyl group of C-7. Biotransformation kinetics indicated that the enzyme converted more than 80% of the apigenin, kaempferol, luteolin and quercetin substrates, which were added at concentration of 70 microM, into corresponding 7-methoxy compounds within 24 h.  相似文献   
85.
86.
Genomic research in any organism encompasses understanding structure of the target genome and genes, their function, and evolution. Brassica rapa , which is phylogenetically related to Arabidopsis thaliana , is an important species with respect to its uses as vegetable, oil, and fodder. The availability of suitable genetic and genomic resources is a prerequisite to undertake genomic research in B. rapa . We have developed reference mapping populations of Chinese cabbage ( B. rapa ssp. pekinensis ) comprising 78 doubled haploid lines and over 250 recombinant inbred lines. Two Bacterial Artificial Chromosome (BAC) libraries, generated by restriction enzymes Hin dIII (KBrH) and Bam HI (KBrB), comprise 56 592 and 50 688 clones, respectively. We have also constructed 22 cDNA libraries from different plant tissues consisting of 104 914 clones with an average length of 575 bp. Initial BAC-end sequence analysis of 1473 clones of the KBrH library led us to understand the structure of B. rapa genome with respect to extent of genic sequences and their annotation, and relative abundance of different types of repetitive DNAs. Full-length sequence analysis of BAC clones revealed extensive triplication of B. rapa DNA segments coupled with variable gene losses within the segments. The formulation of the 'Multinational Brassica Genome Project' has laid the foundation to sequence the complete genome of B. rapa ssp. pekinensis by the international Brassica research community. It has been proposed to undertake BAC-to-BAC sequencing of genetically mapped seed BACs. In recent years, development of bioinformatics tools in Brassica has given a boost to structural genomics research in Brassica species. The research undertaken with the availability of various genomic resources in the public domain has added to our understanding of the structure of B. rapa .  相似文献   
87.
MELDB: a database for microbial esterases and lipases   总被引:1,自引:0,他引:1  
Kang HY  Kim JF  Kim MH  Park SH  Oh TK  Hur CG 《FEBS letters》2006,580(11):2736-2740
MELDB is a comprehensive protein database of microbial esterases and lipases which are hydrolytic enzymes important in the modern industry. Proteins in MELDB are clustered into groups according to their sequence similarities based on a local pairwise alignment algorithm and a graph clustering algorithm (TribeMCL). This differs from traditional approaches that use global pairwise alignment and joining methods. Our procedure was able to reduce the noise caused by dubious alignment in the distantly related or unrelated regions in the sequences. In the database, 883 esterase and lipase sequences derived from microbial sources are deposited and conserved parts of each protein are identified. HMM profiles of each cluster were generated to classify unknown sequences. Contents of the database can be keyword-searched and query sequences can be aligned to sequence profiles and sequences themselves.  相似文献   
88.
Park JA  Jun KR  Han SH  Kim GH  Yoo HW  Hur YJ 《Gene》2012,498(1):131-133
X-linked adrenoleukodystrophy (ALD; MIM #300100) is a neurodegenerative disorder caused by mutations in the ABCD1 adrenoleukodystrophy protein gene. The ABCD1 gene mutations have been reported by laboratories in China and Japan, but not in Korea. This case report describes a Korean boy diagnosed with X-ALD. Direct sequencing for the ABCD1 gene in this boy and his mother detected Tyr620His missense mutation, caused by cDNA nucleotide change 1858 T>C in exon 8 (c.1858T>C). This missense variant was novel and predicted to be possibly damaging by the PolyPhen and SIFT prediction software. Moreover, this is the first report in Korean.  相似文献   
89.
This study developed biomechanical models for hand breakaway strength that account for not only grip force but also hand-handle frictional coupling in generation of breakaway strength. Specifically, models for predicting breakaway strength for two commonly-used handle shapes (circular and rectangular handles) and varying coefficients of friction (COF) between the hand and handle were proposed. The models predict that (i) breakaway strength increases with increasing COF and (ii) a circular handle with a 50.8 mm-diameter results in greater mean breakaway strength than a handle with a rectangular cross-section of 38.1 by 38.1 mm for COFs greater than 0.42. To test these model predictions, breakaway strengths of thirteen healthy young adults were measured for three frequently-encountered COF conditions (represented by three glove types of polyester (COF=0.32), bare hand (COF=0.50), and latex (COF=0.74) against an aluminum handle) and for the two handle shapes. Consistent with the model predictions, mean breakaway strength increased with increasing COF and was greater for the circular than rectangular handle for COFs of 0.50 and 0.74. Examination of breakaway strength normalized to body weight reveals that modification of COF and handle shapes could influence whether one can hold his/her body using the hands or not (thus must fall), highlighting the importance of considering these parameters for fall prevention. The biomechanical models developed herein have the potential to be applied to general handle shapes and COF conditions. These models can be used to optimize handle design to maximize breakaway strength and minimize injuries due to falls from ladders or scaffolds.  相似文献   
90.
As angiogenesis plays important roles in tumor growth and metastasis, searching for antiangiogenic compounds is a promising tactic for treating cancers. Cafestol, a diterpene found mainly in unfiltered coffee, provides benefit through varied biological activity, including antitumorigenic, antioxidative, and anti-inflammatory effects. This study aimed to investigate the effects of cafestol on angiogenesis and to uncover the associated mechanism. We show that cafestol inhibits angiogenesis of human umbilical vascular endothelial cells. This inhibition affects the following specific steps of the angiogenic process: proliferation, migration, and tube formation. The inhibitory effects of cafestol are accompanied by decreasing phosphorylation of FAK and Akt and by a decrease in nitric oxide production. Overall, cafestol inhibits angiogenesis by affecting the angiogenic signaling pathway.  相似文献   
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