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41.
Cadmium is an important environmental pollutant and a potent toxicant to bacteria, algae, and fungi. Mechanisms of Cd+2 toxicity and resistance are variable, depending on the organism. The present work reports the use of live and dead Spirulina sp. for sorption of Cd+2. This investigation shows that this biomass takes up substantial amount of Cd+2 ions. IR spectroscopic study, kinetics models, Langmuir & Freundlich adsorption isotherms, scanning electron microscopic
analysis of Spirulina sp., and the Spirulina sp. treated with different metal ions have been employed to understand the sorption mechanism. Infrared spectra of live Spirulina treated with Cd+2 ions for different lengths of time have been taken to understand the time dependency of metal interaction. 相似文献
42.
K. M. Doshi F. Eudes A. Laroche D. Gaudet 《In vitro cellular & developmental biology. Plant》2007,43(5):429-435
Wheat and triticale plants were transformed by bombardment of isolated scutella with a genetic construct consisting of the
two anthocyanin biosynthesis regulatory genes, C1 and Bperu, each under the control of the Ltp1 embryo-specific promoter. Transgenic plants were obtained in the absence of selective pressure and selectable marker gene
at a transformation frequency of 0.93% and 1.55% in triticale and wheat, respectively. Initial screening of T0 lines was performed by polymerase chain reaction (PCR), and further confirmation of PCR positives was done using real-time
PCR and by phenotypic observation. In this study, quantitative real-time PCR (qRT-PCR) was developed to determine the transgene
copy number in transgenic wheat and triticale. A conserved wheat housekeeping gene, puroindoline-b, was used as an internal control to calculate the transgene copy number in wheat and the SYBR green detection method with
a standard curve, constructed on the basis of serially diluted plasmid, was used to calculate the transgene copy in triticale.
Estimated transgene copies varied from 3 to 8 in wheat and 4 to 7 in triticale lines. The presence of anthocyanin regulatory
genes, promoter, and termination sequences was detected in six wheat lines and four triticale lines. However, anthocyanin-pigmented
embryos were only observed visually in mature T1 seeds of two transgenic wheat lines and a single triticale line. Multisite insertion and reorganization of transgenes was
likely the explanation for the failure of expression for the anthocyanin genes in the remaining wheat and triticale transgenic
lines. 相似文献
43.
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45.
Src family kinases are maintained in an assembled, inactive conformation by intramolecular interactions of their SH2 and SH3 domains. Full catalytic activity requires release of these restraints as well as phosphorylation of Tyr-416 in the activation loop. In previous structures of inactive Src kinases, Tyr-416 and flanking residues are disordered. We report here four additional c-Src structures in which this segment adopts an ordered but inhibitory conformation. The ordered activation loop forms an alpha helix that stabilizes the inactive conformation of the kinase domain, blocks the peptide substrate-binding site, and prevents Tyr-416 phosphorylation. Disassembly of the regulatory domains, induced by SH2 or SH3 ligands, or by dephosphorylation of Tyr-527, could lead to exposure and phosphorylation of Tyr-416. 相似文献
46.
Michelle N Knowlton Tongbin Li Yongliang Ren Brent R Bill Lynda BM Ellis Stephen C Ekker 《BMC bioinformatics》2008,9(1):7
Background
The zebrafish is a powerful model vertebrate amenable to high throughput in vivo genetic analyses. Examples include reverse genetic screens using morpholino knockdown, expression-based screening using enhancer trapping and forward genetic screening using transposon insertional mutagenesis. We have created a database to facilitate web-based distribution of data from such genetic studies. 相似文献47.
This meeting review highlights areas of mutual interest to investigators in the cellular stress response field and to those carrying out wound-healing research. Inflammation, perhaps the major unifying theme of this meeting, is an essential component of the adult wound response and understanding the control of inflammation is a common interest shared with researchers of the cellular stress response. The particular interest of the authors of this review is in chronic non-healing wounds that frequently occur in patients with major illnesses such as diabetes and diseases of the blood vessels. This orientation has undoubtedly influenced the selection of topics. It is fair to say that the authors were often surprised and certainly impressed with the overlapping interests and possibilities for collaboration among investigators of these two research areas. 相似文献
48.
49.
Matthew W. Martin Jennifer Y. Lee David R. Lancia Pui Yee Ng Bingsong Han Jennifer R. Thomason Maureen S. Lynes C. Gary Marshall Chiara Conti Alan Collis Monica Alvarez Morales Kshama Doshi Aleksandra Rudnitskaya Lili Yao Xiaozhang Zheng 《Bioorganic & medicinal chemistry letters》2018,28(12):2143-2147
N-Hydroxy-2-arylisoindoline-4-carboxamides are potent and selective inhibitors of HDAC11. The discovery, synthesis, and structure activity relationships of this novel series of inhibitors are reported. An advanced analog (FT895) displays promising cellular activity and pharmacokinetic properties that make it a useful tool to study the biology of HDAC11 and its potential use as a therapeutic target for oncology and inflammation indications. 相似文献
50.
Loss of phylogenetic information in chorion gene families of Bombyx mori gene conversion 总被引:1,自引:0,他引:1
Regier JC; Weigmann BM; Leclerc RF; Friedlander TP 《Molecular biology and evolution》1994,11(1):72-87
The silkmoth chorion has provided a stimulating model for the study of
evolution and developmental regulation of gene families. Previous attempts
at inferring relationships among chorion sequences have been based on
pairwise comparisons of overall similarity, a potentially problematic
approach. To remedy this, we identified the alignable regions of low
sequence variability and then analyzed this restricted database by
parsimony and neighbor-joining methods. At the deepest level, the chorion
sequence tree is split into two branches, called "alpha" and "beta." Within
each branch, early- and late-expressing genes each constitute monophyletic
groups, while the situation with middle-expressing genes remains uncertain.
The HcB gene family appears to be the most basal beta-branch group, but
this conclusion is qualified because the effect of gene conversion on
branching order is unknown. Previous studies by Eickbush and colleagues
have strongly suggested that ErA, HcA, and HcB families undergo gene
conversion within a gene family, whereas the ErB family does not. The
occurrence of conversion correlates with a particular tree structure;
namely, branch lengths are much greater at the base of the family than at
higher internodes and terminal branches. These observations raise the
possibility that chorion gene families are defined by gene conversion
events (reticulate evolution) rather than by descent with modification
(synapomorphy).
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