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1.
Gian Maria Rossolini Patrizia Muscas Alessandra Chiesurin Giuseppe Satta 《FEMS microbiology letters》1994,119(3):321-328
Abstract Analysis of the Salmonella chromosomal region located upstream of the fimA gene (coding for the major type 1 fimbrial subunit) showed a close linkage of this gene to the folD gene (coding for the enzyme 5,10-methylenetetrahydrofolate dehydrogenase/5, 10-methenyltetrahydrofolate cyclohydrolase), indicating that the fim gene cluster of Salmonella , unlike that of Escherichia coli , has no regulatory genes located upstream of fimA and apparently terminates with this gene. The respective locations of the fim and folD genes in the E. coli and Salmonella genetic maps suggests that the fimA-folD intergenic region of Salmonella encompasses a junctional site of a genetic rearrangement that probably originated from the different chromosomal location of the fim genes in these species. 相似文献
2.
Patrizia Vaccino Heinz-Albert Becker Andrea Brandolini Francesco Salamini Benjamin Kilian 《Molecular genetics and genomics : MGG》2009,281(3):289-300
The celiac disease (CD) is an inflammatory condition characterized by injury to the lining of the small-intestine on exposure
to the gluten of wheat, barley and rye. The involvement of gluten in the CD syndrome has been studied in detail in bread wheat,
where a set of “toxic” and “immunogenic” peptides has been defined. For wheat diploid species, information on CD epitopes
is poor. In the present paper, we have adopted a genomic approach in order to understand the potential CD danger represented
by storage proteins in diploid wheat and sequenced a sufficiently large number of cDNA clones related to storage protein genes
of Triticum monococcum. Four bona fide toxic peptides and 13 immunogenic peptides were found. All the classes of storage proteins were shown to contain harmful
sequences. The major conclusion is that einkorn has the full potential to induce the CD syndrome, as already evident for polyploid
wheats. In addition, a complete overview of the storage protein gene arsenal in T. monococcum is provided, including a full-length HMW x-type sequence and two partial HMW y-type sequences.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
3.
Physiological and Biochemical Mechanisms Involved in the Response to Abscisic Acid in Maize Coleoptiles 总被引:2,自引:0,他引:2
The role of abscisic acid (ABA) in controlling growth and developmenthas been studied in maize (Zea mays L.) coleoptile segments.Application of ABA reduces the elongation rate by about 50%and affects ion fluxes. In particular, proton extrusion is decreasedwhile potassium efflux is greatly enhanced. Apparently, ABAdoes not: seem to influence calcium influx from the apoplastinto the cytosol, but more likely it influences its efflux.Alteration of cytosolic calcium concentration may also be obtainedby increasing its release from internal stores. This possibilitymight be sustained by the increased hydrolysis of phosphatidylinositolupon ABA application. Change in the balance of ion fluxes shouldresult from regulation of transport mechanisms at the membranelevel and should produce changes in the transmembrane electricalpotential. The H+- ATPase and the ATP-dependent calcium transportactivities are both influenced by the treatment with ABA, 55%and 40%, respectively. Under these conditions [Ca2+]cytand pHcyt can be modified and, as a consequence of their regulation,they may play an important role in mediating the physiologicaland biochemical effects of ABA, acting as second intracellularmessengers.
1Research supported by National Research Council of Italy, SpecialProject RAISA, Sub-Project N. 2, Paper n. 2782. 相似文献
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Summary Previous work has shown that the monoclonal antibody 22/18 identifies progenitor cells (blastemal cells) which depend on the nerve for their division in the early stages of limb regeneration in the newt,Notophthalmus viridescens. This antibody also reacts with cultured cells derived from the newt limb, and the intensity of immunoreactivity appears related to cell density and differentiation into myotubes. We report here that the monoclonal antibody 22/18 recognizes a polypeptide (22/18 antigen) which is intracellular and filamentous. Double staining of cells with 22/18 monoclonal antibody and antibodies against various cytoskeletal components indicates that the epitope is expressed on an intermediate filament component. Although this antibody is specific for blastemal cells in cryostat sections of the regenerating limb, its reactivity on immunoblots is not confined to this tissue. The 22/18 antigen is differentially affected by aldehyde fixatives distinguished by the spacing of their reactive groups. While formaldehyde fixation impairs detection of the antigen, ethylene glycol-bis[succinic acid n-hydroxysuccinimide ester] reveals the antigen in sections of normal and regenerating limbs in a distribution that is consistent with the one obtained from immunoblots. We suggest that the 22/18 monoclonal antibody detects a change in protein conformation, probably related to changes in the physiological state of the cell, that occurs transiently during regeneration and possibly during development. 相似文献
6.
Sensitivity of Saccharomyces cerevisiae vegetative cells and spores to antimicrobial compounds 总被引:1,自引:0,他引:1
The sensitivity of Saccharomyces cerevisiae spores and vegetative cells to various antimicrobial compounds was compared. Sulphur dioxide, benzoic acid, potassium sorbate, salicylic acid, nystatin, actidione and pimaricin were tested. Generally, the Saccharomyces spores were more resistant than the corresponding vegetative cells. It was also observed that this greater resistance shown by the spores varied with the antimicrobial compound used. Only potassium sorbate was not selective and killed both vegetative cells and spores at about the same rate. 相似文献
7.
Activation of human ribosomal genes by 5-azacytidine 总被引:2,自引:0,他引:2
Cultured human fibroblasts were exposed to 5-azacytidine which inhibits methylation of newly synthesized DNA. A significant increase in the mean number of Ag-stained active nucleolus organizers has been observed in treated cells. This suggests that DNA methylation is involved in modulation of human rRNA synthesis. 相似文献
8.
Nicoletta zini Patrizia Sabatelli Irene Faenza Andrea Ognibene Nadir M. Maraldi 《The Histochemical journal》1996,28(7):495-504
Summary Some key elements of signal transduction have been identified within the nucleus and demonstrated to be responsive to specific
agonists in numerous cell types. In particular, mitogenic stimuli have been reported to induce, a transient increase of the
nuclear phospholipase C β1 activity, causing the release of inositide-derived second messengers, whereas differentiating stimuli induced a decrease
of the enzyme activity and an increase of nuclear phosphatidylinositol 4,5-bisphosphate (PIP2). Recently, we reported evidence, in human osteosarcoma Saos-2 cell lines, on the presence of specific nuclear phospholipase
C isoforms and on the activation of phospholipase C β1 in the nucleus following the exposure to interleukin-1α. In this study we report immunocytochemical ultrastructural evidence on quantitative variations of PIP2 and phospholipase C β1 amounts in the nucleus of Saos-2 cells at different times of exposure to interleukin-1α. After short periods of culture in the presence of the agonist, the intranuclear amount of PIP2 is decreased, while a translocation of phospholipase C β1 occurs from the cytoplasm to the nucleus, in correspondence with the increased hydrolyzing activity of the enzyme. After
longer periods of incubation with interleukin-1α, on the other hand, the intranuclear amount of PIP2 is restored to initial level, while the amount of phospholipase C β1 is increased both at the nuclear and cytoplasmic level, when its activation is no longer effective. The results, compared
with those obtained in other cell types responsive to given agonists, account for a cell-specific modulation of signal transduction
based on polyphosphoinositide breakdown at the nuclear level. 相似文献
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10.
Anti‐Inflammatory and Antioxidant Actions of Copaiba Oil Are Related to Liver Cell Modifications in Arthritic Rats 下载免费PDF全文