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21.
Chavan SS Tian W Hsueh K Jawaheer D Gregersen PK Chu CC 《Biochimica et biophysica acta》2002,1576(1-2):70-80
Mouse interleukin-four induced gene-1 (mFig1) maps to a region of susceptibility for systemic lupus erythematosus (SLE) that includes the Sle3 locus. To begin examining this relationship in humans, we have isolated and characterized the human homolog of mFig1. Human Fig1 (hFig1) has the same eight exon genomic structure as mFig1. The predicted 63-kDa protein, like mFig1, contains a signal peptide, a large internal sequence that is most similar (43% identical over 484 amino acids) to L-amino acid oxidase (LAAO), and a carboxy terminal domain with no similarity to known genes. When compared to the LAAO crystal structure, hFig1 conserves key residues thought to be involved in catalysis and binding of the flavin adenine dinucleotide cofactor. Surprisingly, the carboxy terminal domains of hFig1 and mFig1 have little similarity (<11% identity), different lengths and amino acid composition. Like mFig1, hFig1 RNA is induced by interleukin-4 (IL-4) in B lymphocytes, and is primarily found in immune tissues. Finally, hFig1 maps to the predicted mFig1 syntenic region on human chromosome 19q13.3-19q13.4, a hot spot for susceptibility to several autoimmune diseases, including SLE. 相似文献
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An efficient protocol was developed for qualitative screening of phosphate-solubilizing bacteria, based upon visual observation.
Our results indicate that, by using our formulation containing bromophenol blue, it is possible to quickly screen on a qualitative
basis the phosphate-solubilizing bacteria. Qualitative analysis of the phosphate solubilized by various groups correlated
well with grouping based upon quantitative analysis of bacteria isolated from soil, effect of carbon, nitrogen, salts, and
phosphate solubilization-defective transposon mutants. However, unlike quantitative analysis methods that involve time-consuming
biochemical procedures, the time for screening phosphate-solubilizing bacteria is significantly reduced by using our simple
protocol. Therefore, it is envisaged that usage of this formulation based upon qualitative analysis will be salutary for the
quick screening of phosphate-solubilizing bacteria. Our results indicate that the formulation can also be used as a quality
control test for expeditiously screening the commercial bioinoculant preparations, based on phosphate solubilizers.
Received: 17 November 2000 / Accepted: 22 December 2000 相似文献
24.
Stimulation of Antioxidant Enzymes and Lipid Peroxidation by UV-B Irradiation in Thylakoid Membranes of Wheat 总被引:3,自引:0,他引:3
In wheat seedlings (Triticum aestivum L. cv. 2329) oxidative stress caused by UV-B radiation led to lipid peroxidation of
thylakoid membrane; it was expressed in term of malondialdehyde (MDA) formation. The peroxidation of lipids of thylakoid membrane
in isolated chloroplasts was prevented when flavonoids quercetin and rutin were supplied into the incubation medium. The activities
of superoxide dismutase, ascorbate peroxidase, and catalase increased during the first hours of UV-B exposure. A comparative
study of UV-B and temperature effects showed different profiles of the antioxidant enzymes and MDA, suggesting that these
two stresses have distinct sites of action. In addition to quantitative increase in flavonoids, qualitative change in flavonoid
composition was also marked during UV-B stress, and a new peak at 330 nm was found as compared to control.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
25.
Ram Chandra Sangeeta Yadav Ram Naresh Bharagava 《World journal of microbiology & biotechnology》2010,26(4):685-692
This study deals with the optimization of bacterial degradation of pyridine raffinate by previously isolated two aerobic bacteria ITRCEM1 (Bacillus cereus) and ITRCEM2 (Alcaligens faecalis) with accession number DQ4335020 and DQ435021, respectively. The degradation of pyridine raffinate was studied by axenic and mixed bacterial consortium at different nutritional and environmental conditions after the removal of formaldehyde from pyridine raffinate (FPPR). Results revealed that the optimum degradation of pyridine raffinate was observed by mixed bacterial culture in presence of glucose (1% w/v) and peptone (0.2% w/v) at 20% FPPR, pH 7.0, temperature 30°C and 120 rpm at 168 h incubation period . The HPLC analysis of degraded pyridine raffinate samples has indicated the complete removal of α, β and γ picoline. Further, the GC–MS analysis of FPPR pyridine raffinate has shown the presence of pyrazine acetonitrile (6.74), 1,3-dioxepin (8.68), 2-pyridine carboxaldehyde (11.26), propiolactone (12.06), 2-butanol (13.10), benzenesulfonic acid (16.22) and 1,4-dimethyl pyperadine while phenol (17.64) and 3,4-dimethyl benzaldehyde as metabolic products of FPPR. 相似文献
26.
Genetic dissection of the role of ethylene in regulating auxin-dependent lateral and adventitious root formation in tomato 总被引:2,自引:0,他引:2
Sangeeta Negi Poornima Sukumar Xing Liu Jerry D. Cohen Gloria K. Muday 《The Plant journal : for cell and molecular biology》2010,61(1):3-15
In this study we investigated the role of ethylene in the formation of lateral and adventitious roots in tomato ( Solanum lycopersicum ) using mutants isolated for altered ethylene signaling and fruit ripening. Mutations that block ethylene responses and delay ripening – Nr ( Never ripe ), gr ( green ripe ), nor ( non ripening ), and rin ( ripening inhibitor ) – have enhanced lateral root formation. In contrast, the epi ( epinastic ) mutant, which has elevated ethylene and constitutive ethylene signaling in some tissues, or treatment with the ethylene precursor 1-aminocyclopropane carboxylic acid (ACC), reduces lateral root formation. Treatment with ACC inhibits the initiation and elongation of lateral roots, except in the Nr genotype. Root basipetal and acropetal indole-3-acetic acid (IAA) transport increase with ACC treatments or in the epi mutant, while in the Nr mutant there is less auxin transport than in the wild type and transport is insensitive to ACC. In contrast, the process of adventitious root formation shows the opposite response to ethylene, with ACC treatment and the epi mutation increasing adventitious root formation and the Nr mutation reducing the number of adventitious roots. In hypocotyls, ACC treatment negatively regulated IAA transport while the Nr mutant showed increased IAA transport in hypocotyls. Ethylene significantly reduces free IAA content in roots, but only subtly changes free IAA content in tomato hypocotyls. These results indicate a negative role for ethylene in lateral root formation and a positive role in adventitious root formation with modulation of auxin transport as a central point of ethylene–auxin crosstalk. 相似文献
27.
Mark R. Herbert Dana L. Siegel Lena Staszewski Charmagne Cayanan Urmi Banerjee Sangeeta Dhamija Jennifer Anderson Amy Fan Li Wang Peter Rix Andrew K. Shiau Tadimeti S. Rao Stewart A. Noble Richard A. Heyman Eric Bischoff Mausumee Guha Ayman Kabakibi Anthony B. Pinkerton 《Bioorganic & medicinal chemistry letters》2010,20(19):5718-5721
Optimization of a screening hit from uHTS led to the discovery of TGR5 agonist 32, which was shown to have activity in a rodent model for diabetes. 相似文献
28.
29.
A pectin lyase (PNL, EC 4.2.2.10) produced extracellularly by the strain of Penicillium oxalicum in solid-state fermentation medium containing deoiled mandarin orange peel meal was purified to apparent homogeneity by a protocol that included ammonium sulfate precipitation, DEAE-Sephadex A-50 and Sephadex G-100 chromatography. The enzyme had molecular mass of 50 kD, as determined by SDS- PAGE and showed optimum pH and temperature at 8.0 and 50 degrees C respectively. It had an isoelectric point (pI) of 5.0 and showed a K(m) of 1.1 mg/ml of citrus pectin. The enzyme was strongly inhibited by Mo4+, Ag+ and Pb2+ and also by polyphenolic compounds, in particular tannic acid. 相似文献
30.
Kamerzell TJ Joshi SB McClean D Peplinskie L Toney K Papac D Li M Middaugh CR 《Protein science : a publication of the Protein Society》2007,16(6):1193-1203
The interaction of four representative polyanions with parathyroid hormone (PTH) residues 1-84 has been investigated utilizing a variety of spectroscopic and calorimetric techniques. Each of the polyanions employed demonstrate enthalpically driven binding to PTH (1-84) with significant affinity. The polyanions heparin, dextran sulfate, phytic acid, and sucrose octasulfate induce alpha-helical structure in PTH to varying extents depending on the ratio of polyanion to protein employed. Intrinsic and extrinsic fluorescence spectroscopy suggests significant protein tertiary structure alteration upon polyanion binding. Although structural modification occurred upon polyanion binding, PTH colloidal stability was increased depending on the ratio of polyanion to protein used. Nevertheless, the bioactivity of PTH in the presence of various ratios of heparin was not altered. The potential biological significance of PTH/polyanion interactions is discussed. 相似文献