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91.
Young Mi Kim Joongku Lee Sang-Hong Park Changyoung Lee Jae Won Lee DongHyuk Lee Nahyun Kim Dongho Lee Hyang Yeon Kim Choong Hwan Lee 《Plant cell reports》2012,31(11):2085-2097
In this study, 39 specimens belonging to Lespedeza species (Lespedeza cyrtobotrya, L. bicolor, L. maximowiczii, and Lespedeza cuneata) (Leguminosae) were classified phenotypically and genotypically. We constructed a phylogenetic tree based on the combined nrDNA (internal transcribed spacer; ITS) and cpDNA (trnL-trnF) sequences with the aim of classifying the genotypes. Samples were mainly divided into three genotypes. Samples of L. cyrtobotrya and L. bicolor were mixed in a single branch, whereas samples of L. maximowiczii and L. cuneata were clustered within species, respectively. We performed a liquid chromatography–electrospray ionization–mass spectrometry-based metabolite profiling analysis to classify the phenotypes. Multivariate statistical analyses such as principal component analysis (PCA) and hierarchical clustering analysis (HCA) were used for the clustering pattern analysis and distance analysis between species, respectively. According to the PCA and HCA results, leaves were classified into four phenotypes according to species. In both the genetic and chemotaxonomic classification methods, the distance between L. cyrtobotrya and L. bicolor was the closest between species, and L. cuneata was the farthest away from the other three species. Additionally, orthogonal partial least squares-discriminant analysis was employed to identify significantly different phytochemicals between species. We classified L. cyrtobotrya and L. bicolor by identifying significantly different phytochemicals. Interestingly, leaves and stems showed different phenotypic classifications based on the chemotaxonomic classification. Stem samples of the other three species were mixed regardless of species, whereas L. cyrtobotrya stem samples were clustered within species. The phenotypic classification of leaves coincided more with the genotypic classification than that of stems. Key message We classified four wild-type Lespedeza sp. by analyzing the combined nrDNA (ITS) and cpDNA (trnL-trnF) sequences. We also classified leaves and stems of Lespedeza sp. by applying liquid chromatography–mass spectroscopy-based metabolite profiling. 相似文献
92.
Kim BK Song GC Hong GH Seong WK Kim SY Jeong H Kang SG Kwon SK Lee CH Song JY Yu DS Park MS Cho SH Kim JF 《Journal of bacteriology》2012,194(14):3751-3752
Shiga toxin-producing Escherichia coli causes bloody diarrhea and hemolytic-uremic syndrome and serious outbreaks worldwide. Here, we report the draft genome sequence of E. coli NCCP15657 isolated from a patient. The genome has virulence genes, many in the locus of enterocyte effacement (LEE) island, encoding a metalloprotease, the Shiga toxin, and constituents of type III secretion. 相似文献
93.
The biosynthetic gene cluster for bluensomycin, a member of the aminoglycoside family of antibiotics, was isolated and characterized from the bluensomycin producing strain, Streptomyces bluensis ATCC27420. PCR primers were designed specifically to amplify a segment of the dTDP-glucose synthase gene based on its conserved sequences among several actinomycete strains. By screening a cosmid library using amplified PCR fragments, a 30-kb DNA fragment was isolated. Sequence analysis identified 15 open reading frames (ORFs), eight of which had previously been identified by Piepersberg et al. But seven are novel to this study. We demonstrated that one of these ORFs, blmA, confers resistance against the antibiotic dihydrostreptomycin, and another, blmD, encodes a dTDP-glucose synthase. These findings suggest that the isolated gene cluster is very likely to be responsible for the biosynthesis of bluensomycin. 相似文献
94.
Erlanson DA Lam JW Wiesmann C Luong TN Simmons RL DeLano WL Choong IC Burdett MT Flanagan WM Lee D Gordon EM O'Brien T 《Nature biotechnology》2003,21(3):308-314
Cysteine aspartyl protease-3 (caspase-3) is a mediator of apoptosis and a therapeutic target for a wide range of diseases. Using a dynamic combinatorial technology, 'extended tethering', we identified unique nonpeptidic inhibitors for this enzyme. Extended tethering allowed the identification of ligands that bind to discrete regions of caspase-3 and also helped direct the assembly of these ligands into small-molecule inhibitors. We first designed a small-molecule 'extender' that irreversibly alkylates the cysteine residue of caspase-3 and also contains a thiol group. The modified protein was then screened against a library of disulfide-containing small-molecule fragments. Mass-spectrometry was used to identify ligands that bind noncovalently to the protein and that also form a disulfide linkage with the extender. Linking the selected fragments with binding elements from the extenders generates reversible, tight-binding molecules that are druglike and distinct from known inhibitors. One molecule derived from this approach inhibited apoptosis in cells. 相似文献
95.
Summary
Methylobacterium sp. KCTC 0048 isolated from soil, could synthesize a variety of copolyesters when secondary carbon substrates were added to nitrogen-limited cultures containing methanol as a major carbon and energy source. The copolyester of 3-hydroxy-butyrate and 3-hydroxyvalerate, P(3HB-co-3HV) accumulated when valeric acid, pentanol or heptanoic acid was added to the nitrogen-limited medium containing methanol. The copolyester of 3-hydroxybutyrate and 4-hydroxybutyrate, P(3HB-co-4HB) was synthesized from 4-hydroxybutyrate, 1,4-butanediol, or -butyrolactone, and the copolyester of 3-hydroxybutyrate and 3-hydroxypropionate (P(3HB-co-3HP)), from 3-hydroxypropionate as the secondary carbon substrates, respectively. 相似文献
96.
Moon JC Hah YS Kim WY Jung BG Jang HH Lee JR Kim SY Lee YM Jeon MG Kim CW Cho MJ Lee SY 《The Journal of biological chemistry》2005,280(31):28775-28784
Although biochemical properties of 2-Cys peroxiredoxins (Prxs) have been extensively studied, their real physiological functions in higher eukaryotic cells remain obscure and certainly warrant further study. Here we demonstrated that human (h) PrxII, a cytosolic isotype of human 2-Cys Prx, has dual functions as a peroxidase and a molecular chaperone, and that these different functions are closely associated with its adoption of distinct protein structures. Upon exposure to oxidative stress, hPrxII assumes a high molecular weight complex structure that has a highly efficient chaperone function. However, the subsequent removal of stressors induces the dissociation of this protein structure into low molecular weight proteins and triggers a chaperone-to-peroxidase functional switch. The formation of a high molecular weight hPrxII complex depends on the hyperoxidation of its N-terminal peroxidatic Cys residue as well as on its C-terminal domain, which contains a "YF motif" that is exclusively found in eukaryotic 2-Cys Prxs. A C-terminally truncated hPrxII exists as low and oligomeric protein species and does not respond to oxidative stress. Moreover, this C-terminal deletion of hPrxII converted it from an oxidation-sensitive to a hyperoxidation-resistant form of peroxidase. When functioning as a chaperone, hPrxII protects HeLa cells from H(2)O(2)-induced cell death, as measured by a terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling assay and fluorescence-activated cell sorting analysis. 相似文献
97.
Choong PF Kunisada T Slavin J Schlicht S Hicks R 《International Seminars in Surgical Oncology : ISSO》2004,1(1):10
INTRODUCTION: Heterogeneity of cartilage tumours may confound accurate diagnosis and grading resulting in under and over treatment. Improved preoperative assessment of malignancy and grade would be invaluable for developing a rational plan for treatment. We examined correlations between nuclear tracer avidity and malignancy grade in cartilage tumours. METHODS: Between 1996 and 2000, 92 consecutive patients with cartilaginous tumours (50 benign, 42 non-metastatic malignant) underwent nuclear scanning. Thallium-201 (TL-201) and pentavalent dimercaptosuccinic acid (DMSAV) were used as nuclear isotopes. Scanning with these agents was performed on separate days 48 hours apart. Static and SPECT images were obtained at 30 m and 4 h after injection of nuclear tracer. Pathology review was undertaken blinded to the results of the nuclear scans and correlations between histologic results and trace uptake at 4 hours examined. RESULTS: 25 patients with negative DMSAV had benign tumours. 15/17 tumours with positive TL-201 had malignant tumours. 11/13 patients with both positive DMSAV and TL-201 scans had intermediate or high grade tumours and 4 of these developed metastases. We have developed an algorithm for the management of patients with tumours that aims to avoid over treatment of low grade tumours and under treatment of high grade tumours. CONCLUSION: Functional nuclear scanning with TL-201 and DMSAV complements other imaging modalities in the management of cartilaginous tumours. 相似文献
98.
Evidence that amylin stimulates lipolysis in vivo: a possible mediator of induced insulin resistance
Ye JM Lim-Fraser M Cooney GJ Cooper GJ Iglesias MA Watson DG Choong B Kraegen EW 《American journal of physiology. Endocrinology and metabolism》2001,280(4):E562-E569
The present study investigated the role of amylin in lipid metabolism and its possible implications for insulin resistance. In 5- to 7-h-fasted conscious rats, infusion of rat amylin (5 nmol/h for 4 h) elevated plasma glucose, lactate, and insulin (P <0.05 vs. control, repeated-measures ANOVA) with peak values occurring within 60 min. Despite the insulin rise, plasma nonesterified fatty acids (NEFA) and glycerol were also elevated (P < 0.001 vs. control), and these elevations (80% above basal) were sustained over the 4-h infusion period. Although unaltered in plasma, triglyceride content in liver was increased by 28% (P < 0.001) with a similar tendency in muscle (18%, P = 0.1). Infusion of the rat amylin antagonist amylin-(8-37) (125 nmol/h) induced opposite basal plasma changes to amylin, i.e., lowered plasma NEFA, glycerol, glucose, and insulin levels (all P < 0.05 vs. control); additionally, amylin-(8-37) blocked amylin-induced elevations of these parameters (P < 0.01). Treatment with acipimox (10 mg/kg), an anti-lipolytic agent, before or after amylin infusion blocked amylin's effects on plasma NEFA, glycerol, and insulin but not on glucose and lactate. We conclude that amylin could exert a lipolytic-like action in vivo that is blocked by and is opposite to effects of its antagonist amylin-(8-37). Further studies are warranted to examine the physiological implications of lipid mobilization for amylin-induced insulin resistance. 相似文献
99.
An integrated approach in the discovery and characterization of a novel nuclear protein over-expressed in liver and pancreatic tumors 总被引:9,自引:0,他引:9
Choong ML Tan LK Lo SL Ren EC Ou K Ong SE Liang RC Seow TK Chung MC 《FEBS letters》2001,496(2-3):109-116
An integrated approach in protein discovery through the use of multidisciplinary tools was reported. A novel protein, Hcc-1, was identified by analysis of the hepatocellular carcinoma (HCC)-M cell proteome. The assembled EST sequence of the 210 amino acid novel protein was subsequently confirmed by rapid amplification of cDNA ends (RACE). A total of 687 bp at the 5' untranslated region of Hcc-1 was identified. Promoter activity and several upstream open reading frames (uORFs) were demonstrated at this region. Bioinformatics prediction showed that the first 42 amino acids of the protein is a SAP domain with sequence matches to hnRNP from various vertebrate species. The Hcc-1 protein was localized to the cell nucleus while the gene was localized to chromosome 7q22.1. Hcc-1 cDNA level was increased in pancreatic adenocarcinoma. The level was also increased in well-differentiated hepatocellular carcinoma but decreases as the carcinoma progressed to a poorly differentiated stage. 相似文献
100.
Young Ah Lee Hang-Rae Kim Jeong Seon Lee Hae Woon Jung Hwa Young Kim Gyung Min Lee Jieun Lee Ji Hyun Sim Sae Jin Oh Doo Hyun Chung Choong Ho Shin Sei Won Yang 《PloS one》2015,10(12)