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991.
The human protein PTD012 is the longer product of an alternatively spliced gene and was described to be localized in the nucleus. The X-ray structure analysis at 1.7 A resolution of PTD012 through SAD phasing reveals a monomeric protein and a novel fold. The shorter splice form was also studied and appears to be unfolded and non-functional. The structure of PTD012 displays an alphabetabetaalpha four-layer topology. A metal ion residing between the central beta-sheets is partially coordinated by three histidine residues. X-ray absorption near-edge structure (XANES) analysis identifies the PTD012-bound ion as Zn(2+). Tetrahedral coordination of the ion is completed by the carboxylate oxygen atom of an acetate molecule taken up from the crystallization buffer. The binding of Zn(2+) to PTD012 is reminiscent of zinc-containing enzymes such as carboxypeptidase, carbonic anhydrase, and beta-lactamase. Biochemical assays failed to demonstrate any of these enzyme activities in PTD012. However, PTD012 exhibits ester hydrolase activity on the substrate p-nitrophenyl acetate.  相似文献   
992.
The biodegradation of photographic gelatin grade (Bloom 225) material was studied by viscometry in aqueous solution (at 37 °C, 6.67% w/w) using filamentous fungi isolated and identified from cinematographic film stored in different Spanish archives. From viscosity data, different variables such as molecular weight and chain scission were calculated. To ensure initial spore suspension concentration was standardized for all the biodegradation experiments, a correlation between transmittance at 530 nm of fungal spore suspensions and the corresponding cytometric determination of populations was established for all the fungal strains studied in this work. The bioassay experiments were carried out at 25 and 4 °C using an initial concentration of fungi of 4.5×105 conidia/mL except in the case of the genus Alternaria, where the concentration was 10 times lower. The fungal strains were three species of Aspergillus, i.e., A .ustus, A. nidulans var. nidulans, A. versicolor, seven Penicillium chrysogenum strains, and Cladosporium cladosporioides, Alternaria alternata, Mucor racemosus, Phoma glomerata, and Trichoderma longibrachiatum. All were gelatinase positive. Through the viscosity decay profiles with bioassay-time and the corresponding calculated chain scission, the relative quantitative gelatinase efficiency of these fungi has been evaluated.  相似文献   
993.
Trivalent influenza virus A/Duck/Singapore (H5N3), A/Panama (H3N2), and B/Guandong vaccine preparations were used in a randomized, controlled, dose-ranging phase I study. The vaccines were prepared from highly purified hemagglutinin and neuraminidase from influenza viruses propagated in embryonated chicken eggs and inactivated with formaldehyde. We assigned 100 participants to six vaccine groups, as follows. Three intranasally vaccinated groups received 7.5-microg doses of hemagglutinin from each virus strain with either 3, 10, or 30 microg of heat-labile Escherichia coli enterotoxin (LTK63) and 990 microg of a supramolecular biovector; one intranasally vaccinated group was given 7.5-microg doses of hemagglutinin with 30 microg of LTK63 without the biovector; and another intranasally vaccinated group received saline solution as a placebo. The final group received an intramuscular vaccine containing 15 microg hemagglutinin from each strain with MF59 adjuvant. The immunogenicity of two intranasal doses, delivered by syringe as drops into both nostrils with an interval of 1 week between, was compared with that of two inoculations by intramuscular delivery 3 weeks apart. The intramuscular and intranasal vaccine formulations were both immunogenic but stimulated different limbs of the immune system. The largest increase in circulating antibodies occurred in response to intramuscular vaccination; the largest mucosal immunoglobulin A (IgA) response occurred in response to mucosal vaccination. Current licensing criteria for influenza vaccines in the European Union were satisfied by serum hemagglutination inhibition responses to A/Panama and B/Guandong hemagglutinins given with MF59 adjuvant by injection and to B/Guandong hemagglutinin given intranasally with the highest dose of LTK63 and the biovector. Geometric mean serum antibody titers by hemagglutination inhibition and microneutralization were significantly higher for each virus strain at 3 and 6 weeks in recipients of the intramuscular vaccine than in recipients of the intranasal vaccine. The immunogenicity of the intranasally delivered experimental vaccine varied by influenza virus strain. Mucosal IgA responses to A/Duck/Singapore (H5N3), A/Panama (H3N2), and B/Guandong were highest in participants given 30 microg LTK63 with the biovector, occurring in 7/15 (47%; P=0.0103), 8/15 (53%; P=0.0362), and 14/15 (93%; P=0.0033) participants, respectively, compared to the placebo group. The addition of the biovector to the vaccine given with 30 microg LTK63 enhanced mucosal IgA responses to A/Duck/Singapore (H5N3) (P=0.0491) and B/Guandong (P=0.0028) but not to A/Panama (H3N2). All vaccines were well tolerated.  相似文献   
994.
Previously, we reported that Galactoxylomannan (GalXM) activates the extrinsic and intrinsic apoptotic pathways through an interaction with the glycoreceptors on T cells. In this study we establish the role of the glycoreceptor CD45 in GalXM-induced T cell apoptosis, using CD45+/+ and CD45−/− cell lines, derived from BW5147 murine T cell lymphoma. Our results show that whereas CD45 expression is not required for GalXM association by the cells, it is essential for apoptosis induction. In CD45+/+ cells, CD45 triggering by GalXM reduces the activation of Lck, ZAP70 and Erk1/2. Conversely, in CD45−/− cells, Lck was hyperphosphorylated and did not show any modulation after GalXM stimulation. On the whole, our findings provide evidence that the negative regulation of Lck activation occurs via CD45 engagement. This appears to be related to the capacity of GalXM to antagonize T cell activation and induce T cell death. Overall this mechanism may be responsible for the immune paralysis that follows GalXM administration and could explain the powerful immunosuppression that accompanies cryptococcosis.  相似文献   
995.
Sphaerobacter thermophilus Demharter et al. 1989 is the sole and type species of the genus Sphaerobacter, which is the type genus of the family Sphaerobacteraceae, the order Sphaerobacterales and the subclass Sphaerobacteridae. Phylogenetically, it belongs to the genomically little studied class of the Thermomicrobia in the bacterial phylum Chloroflexi. Here, the genome of strain S 6022(T) is described which is an obligate aerobe that was originally isolated from an aerated laboratory-scale fermentor that was pulse fed with municipal sewage sludge. We describe the features of this organism, together with the complete genome and annotation. This is the first complete genome sequence of the thermomicrobial subclass Sphaerobacteridae, and the second sequence from the chloroflexal class Thermomicrobia. The 3,993,764 bp genome with its 3,525 protein-coding and 57 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.  相似文献   
996.
Ilyobacter polytropus Stieb and Schink 1984 is the type species of the genus Ilyobacter, which belongs to the fusobacterial family Fusobacteriaceae. The species is of interest because its members are able to ferment quite a number of sugars and organic acids. I. polytropus has a broad versatility in using various fermentation pathways. Also, its members do not degrade poly-β-hydroxybutyrate but only the monomeric 3-hydroxybutyrate. This is the first completed genome sequence of a member of the genus Ilyobacter and the second sequence from the family Fusobacteriaceae. The 3,132,314 bp long genome with its 2,934 protein-coding and 108 RNA genes consists of two chromosomes (2 and 1 Mbp long) and one plasmid, and is a part of the Genomic Encyclopedia of Bacteria and Archaea project.  相似文献   
997.
Ignisphaera aggregans Niederberger et al. 2006 is the type and sole species of genus Ignisphaera. This archaeal species is characterized by a coccoid-shape and is strictly anaerobic, moderately acidophilic, heterotrophic hyperthermophilic and fermentative. The type strain AQ1.S1(T) was isolated from a near neutral, boiling spring in Kuirau Park, Rotorua, New Zealand. This is the first completed genome sequence of the genus Ignisphaera and the fifth genome (fourth type strain) sequence in the family Desulfurococcaceae. The 1,875,953 bp long genome with its 2,009 protein-coding and 52 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project.  相似文献   
998.
Sulfurospirillum deleyianum Schumacher et al. 1993 is the type species of the genus Sulfurospirillum. S. deleyianum is a model organism for studying sulfur reduction and dissimilatory nitrate reduction as an energy source for growth. Also, it is a prominent model organism for studying the structural and functional characteristics of cytochrome c nitrite reductase. Here, we describe the features of this organism, together with the complete genome sequence and annotation. This is the first completed genome sequence of the genus Sulfurospirillum. The 2,306,351 bp long genome with its 2,291 protein-coding and 52 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.  相似文献   
999.
Vulcanisaeta distributa Itoh et al. 2002 belongs to the family Thermoproteaceae in the phylum Crenarchaeota. The genus Vulcanisaeta is characterized by a global distribution in hot and acidic springs. This is the first genome sequence from a member of the genus Vulcanisaeta and seventh genome sequence in the family Thermoproteaceae. The 2,374,137 bp long genome with its 2,544 protein-coding and 49 RNA genes is a part of the Genomic Encyclopedia of Bacteriaand Archaea project.  相似文献   
1000.
BackgroundMass spectrometry (MS) is becoming the gold standard for biomarker discovery. Several MS-based bioinformatics methods have been proposed for this application, but the divergence of the findings by different research groups on the same MS data suggests that the definition of a reliable method has not been achieved yet. In this work, we propose an integrated software platform, MASCAP, intended for comparative biomarker detection from MALDI-TOF MS data.ResultsMASCAP integrates denoising and feature extraction algorithms, which have already shown to provide consistent peaks across mass spectra; furthermore, it relies on statistical analysis and graphical tools to compare the results between groups. The effectiveness in mass spectrum processing is demonstrated using MALDI-TOF data, as well as SELDI-TOF data. The usefulness in detecting potential protein biomarkers is shown comparing MALDI-TOF mass spectra collected from serum and plasma samples belonging to the same clinical population.ConclusionsThe analysis approach implemented in MASCAP may simplify biomarker detection, by assisting the recognition of proteomic expression signatures of the disease. A MATLAB implementation of the software and the data used for its validation are available at http://www.unich.it/proteomica/bioinf.  相似文献   
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