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71.
Marina S. Trofimova Irina N. Smolenskaya Artem V. Drabkin Alexander V. Galkin Alexey V. Babakov 《Physiologia plantarum》1997,99(2):221-226
Sugar beet ( Beta vulgaris L.) root suspension-cultured cells were converted to protoplasts which responded to fusicoccin (FC) by a rise in cytoplasmic pH (pHcyt ) averaging 0.25 units in the fluorimetric assay. This effect was blocked by erythrosin B, a specific inhibitor of the plasma membrane H+ -ATPase. A protein kinase inhibitor, staurosporine also caused cytosolic alkalinization that was sensitive to H+ -ATPase inhibitors. Most strikingly, the effect of staurosporine was suppressed by fusicoccin and vice versa. Addition of okadaic acid, entailing overall protein phosphorylation, also led to H+ -ATPase activation, whereupon fusicoccin lost its effect on proton transport. In parallel, kinetic and inhibitor analyses demonstrated that FC binding to the protoplast plasma membrane involved two sites with dissociation constants of 1 n M and 0.2 μ M and was indifferent to phosphorylation and dephosphorylation inhibitors. Thus, it could be concluded that (1) the effect of FC on cytoplasmic pH probably depends on the phosphorylation state of plasma membrane proteins and may have either sign; (2) the activation of H+ -ATPase by FC most likely proceeds directly through conformational receptor-enzyme interaction. 相似文献
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75.
Rodriguez-Kern A Gegelashvili M Schousboe A Zhang J Sung L Gegelashvili G 《Neurochemistry international》2003,43(4-5):363-370
76.
In a batch cultivation of Pichia pastoris expressing Candida rugosa lipase 1 (CRL1), secretion of 200 microg lipase ml(-1) of culture was achieved in sorbitol-based medium. However, a large amount of recombinant protein was retained intracellularly throughout the fermentation, pointing to the transport step as a major bottleneck. Therefore a translational fusion with the green fluorescent protein (GFP) was constructed that was expressed and transported similarly to the native lipase and retained catalytic activity. This analytical tool enables a rapid monitoring of product localization and amount, based on GFP-associated fluorescence. 相似文献
77.
Sophie Lavoine‐Hanneguelle Christine Périchet Nicolas Schnaebele Marina Humbert 《化学与生物多样性》2014,11(11):1798-1820
For over the past 20 years, a remarkable development in the study and search of natural products has been observed. This is linked to a new market trend towards ecology and also due to new regulations. This could be a rupture, but also a real booster for creativity. Usually, in the flavor and fragrance field, creativity was boosted by the arrival of new synthetic molecules. Naturals remained the traditional, century‐old products, protected by secrecy and specific know‐how from each company. Regulatory restrictions or eco‐friendly certification constraints like hexane‐free processes triggered an important brainstorming in the industry. As a result, we developed new eco‐friendly processes including supercritical CO2 extraction, allowing fresh plants to be used to obtain industrial flower extracts (Jasmine Grandiflorum, Jasmine Sambac, Orange blossom). These extracts are analyzed by GC, GC/MS, GC? O, and HPTLC techniques. New or unusual raw materials can also be explored, but the resulting extracts have to be tested for safety reasons. Some examples are described. 相似文献
78.
A phenological study on allergenic plants was carried out in Padua during 1995 in order to identify spontaneous and cultivated
allergenic species in an urban area and their distribution, and to evaluate the relationship between anthesis length and airborne
pollen concentrations. In some cases, there was no temporal overlap between phenological and aerobiological data, in particular
forCorylaceae, Betulaceae, Chenopodiaceae, Amaranthaceae, Polygonaceae and Fagaceae. 相似文献
79.
Tinto N Zagari A Capuano M De Simone A Capobianco V Daniele G Giugliano M Spadaro R Franzese A Sacchetti L 《PloS one》2008,3(4):e1870
Background
Maturity onset diabetes of the young type 2 (or GCK MODY) is a genetic form of diabetes mellitus provoked by mutations in the glucokinase gene (GCK).Methodology/Principal Findings
We screened the GCK gene by direct sequencing in 30 patients from South Italy with suspected MODY. The mutation-induced structural alterations in the protein were analyzed by molecular modeling. The patients'' biochemical, clinical and anamnestic data were obtained. Mutations were detected in 16/30 patients (53%); 9 of the 12 mutations identified were novel (p.Glu70Asp, p.Phe123Leu, p.Asp132Asn, p.His137Asp, p.Gly162Asp, p.Thr168Ala, p.Arg392Ser, p.Glu290X, p.Gln106_Met107delinsLeu) and are in regions involved in structural rearrangements required for catalysis. The prevalence of mutation sites was higher in the small domain (7/12: ∼59%) than in the large (4/12: 33%) domain or in the connection (1/12: 8%) region of the protein. Mild diabetic phenotypes were detected in almost all patients [mean (SD) OGTT = 7.8 mMol/L (1.8)] and mean triglyceride levels were lower in mutated than in unmutated GCK patients (p = 0.04).Conclusions
The prevalence of GCK MODY is high in southern Italy, and the GCK small domain is a hot spot for MODY mutations. Both the severity of the GCK mutation and the genetic background seem to play a relevant role in the GCK MODY phenotype. Indeed, a partial genotype-phenotype correlation was identified in related patients (3 pairs of siblings) but not in two unrelated children bearing the same mutation. Thus, the molecular approach allows the physician to confirm the diagnosis and to predict severity of the mutation. 相似文献80.
Yann Cormerais Marina Pagnuzzi‐Boncompagni Sandra Schrtter Sandy Giuliano Eric Tambutt Hitoshi Endou Michael F. Wempe Gilles Pags Jacques Pouyssgur Vincent Picco 《Journal of cellular and molecular medicine》2019,23(4):2711-2718
Most cases of medulloblastoma (MB) occur in young children. While the overall survival rate can be relatively high, current treatments combining surgery, chemo‐ and radiotherapy are very destructive for patient development and quality of life. Moreover, aggressive forms and recurrences of MB cannot be controlled by classical therapies. Therefore, new therapeutic approaches yielding good efficacy and low toxicity for healthy tissues are required to improve patient outcome. Cancer cells sustain their proliferation by optimizing their nutrient uptake capacities. The L‐type amino acid transporter 1 (LAT1) is an essential amino acid carrier overexpressed in aggressive human cancers that was described as a potential therapeutic target. In this study, we investigated the therapeutic potential of JPH203, a LAT1‐specific pharmacological inhibitor, on two independent MB cell lines belonging to subgroups 3 (HD‐MB03) and Shh (DAOY). We show that while displaying low toxicity towards normal cerebral cells, JPH203 disrupts AA homeostasis, mTORC1 activity, proliferation and survival in MB cells. Moreover, we demonstrate that a long‐term treatment with JPH203 does not lead to resistance in MB cells. Therefore, this study suggests that targeting LAT1 with JPH203 is a promising therapeutic approach for MB treatment. 相似文献