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71.
Methyl jasmonate affects phenolic metabolism and gene expression in blueberry (Vaccinium corymbosum) 下载免费PDF全文
Giacomo Cocetta Mara Rossoni Claudio Gardana Ilaria Mignani Antonio Ferrante Anna Spinardi 《Physiologia plantarum》2015,153(2):269-283
Blueberry (Vaccinium corymbosum) is a fruit very much appreciated by consumers for its antioxidant potential and health‐promoting traits. Its beneficial potential properties are mainly due to a high content of anthocyanins and their amount can change after elicitation with methyl jasmonate. The aim of this work is to evaluate the changes in expression of several genes, accumulation of phenolic compounds and alterations in antioxidant potential in two different blueberry cultivars (‘Duke’ and ‘Blueray’) in response to methyl jasmonate (0.1 mM). Results showed that 9 h after treatment, the expression of phenylalanine ammonium lyase, chalcone synthase and anthocyanidin synthase genes was stimulated more in the ‘Blueray’ variety. Among the phenols measured an increase was recorded also for epicatechin and anthocyanin concentrations. ‘Duke’ is a richer sourche of anthocyanins compared to ‘Blueray’, treatment with methyl jasmonate promoted in ‘Blueray’ an increase in pigments as well as in the antioxidant potential, especially in fully ripe berries, but treated ‘Duke’ berries had greater levels, which were not induced by methyl jasmonate treatment. In conclusion, methyl jasmonate was, in some cases, an effective elicitor of phenolic metabolism and gene expression in blueberry, though with different intensity between cultivars. 相似文献
72.
Finore Ilaria Kasavi Ceyda Poli Annarita Romano Ida Oner Ebru Toksoy Kirdar Betul Dipasquale Laura Nicolaus Barbara Lama Licia 《World journal of microbiology & biotechnology》2011,27(10):2425-2433
This study reports the purification and biochemical characterization of a raw starch-digesting α-amylase from Geobacillus thermoleovorans subsp. stromboliensis subsp. nov. (strain PizzoT). The molecular weight was estimated to be 58 kDa by SDS–PAGE. The enzyme was highly active over a wide range of pH from
4.0–10.0. The optimum temperature of the enzyme was 70°C. It showed extreme thermostability in the presence of Ca2+, retaining 50% of its initial activity after 90 h at 70°C. The enzyme efficiently hydrolyzed 20% (w/v) of raw starches, concentration
normally used in starch industries. The α-amylase showed an high stability in presence of many organic solvents. In particular
the residual activity was of 73% in presence of 15% (v/v) ethyl alcohol, which corresponds to ethanol yield in yeast fermentation
process. By analyzing its complete amyA gene sequence (1,542 bp), the enzyme was proposed to be a new α-amylase. 相似文献
73.
Miles TJ Barfoot C Brooks G Brown P Chen D Dabbs S Davies DT Downie DL Eyrisch S Giordano I Gwynn MN Hennessy A Hoover J Huang J Jones G Markwell R Rittenhouse S Xiang H Pearson N 《Bioorganic & medicinal chemistry letters》2011,21(24):7483-7488
As part of our wider efforts to exploit novel mode of action antibacterials, we have discovered a series of cyclohexyl-amide compounds that has good Gram positive and Gram negative potency. The mechanism of action is via inhibition of bacterial topoisomerases II and IV. We have investigated various subunits in this series and report advanced studies on compound 7 which demonstrates good PK and in vivo efficacy properties. 相似文献
74.
Miles TJ Axten JM Barfoot C Brooks G Brown P Chen D Dabbs S Davies DT Downie DL Eyrisch S Gallagher T Giordano I Gwynn MN Hennessy A Hoover J Huang J Jones G Markwell R Miller WH Minthorn EA Rittenhouse S Seefeld M Pearson N 《Bioorganic & medicinal chemistry letters》2011,21(24):7489-7495
We have identified a series of amino-piperidine antibacterials with a good broad spectrum potency. We report the investigation of various subunits in this series and advanced studies on compound 8. Compound 8 possesses good pharmacokinetics, broad spectrum antibacterial activity and demonstrates oral efficacy in a rat lung infection model. 相似文献
75.
Microautophagy of cytosolic proteins by late endosomes 总被引:2,自引:0,他引:2
Sahu R Kaushik S Clement CC Cannizzo ES Scharf B Follenzi A Potolicchio I Nieves E Cuervo AM Santambrogio L 《Developmental cell》2011,20(1):131-139
Highlights? Late endosomes take up cytosolic proteins through membrane invaginations ? Endosomal microautophagy (eMI) requires multivesicular body formation ? hsc70 mediates selective targeting of cytosolic proteins during eMI ? hsc70 binds to the endosomal membrane through its polybasic cluster 相似文献
76.
Kongkamnerd J Milani A Cattoli G Terregino C Capua I Beneduce L Gallotta A Pengo P Fassina G Monthakantirat O Umehara K De-Eknamkul W Miertus S 《Journal of biomolecular screening》2011,16(7):755-764
Many assays aimed to test the inhibitory effects of synthetic molecules, and naturally occurring products on the neuraminidase activity exploit the hydrolysis of 2'-O-(4-methylumbelliferyl)-N-acetylneuraminic acid (4-MUNANA). The amount of the released product, 4-methylumbelliferone (4-MU), is then measured fluorimetrically. The authors attempted an analysis of the inhibitory properties of 35 naturally occurring flavonoids on neuraminidase N3, where only 29 of them were sufficiently soluble in the assay medium. During the analysis, the authors noticed a strong quenching effect due to the test compounds on the fluorescence of 4-MU. The quenching constants for the flavonoids were determined according to the Stern-Volmer approach. The extent of fluorescence reduction due to quenching and the magnitude of the fluorescence reduction measured in the inhibition assays were comparable: for 11 of 29 compounds, the two values were found to be coincident within the experimental uncertainty. These data were statistically analyzed for correlation by calculating the pertinent Pearson correlation coefficient. Inhibition and quenching were found to be positively correlated (r = 0.71, p(uncorr) = 1.5 × 10(-5)), and the correlation was maintained for the whole set of tested compounds. Altogether, the collected data imply that all of the tested flavonoids could produce false-positive results in the neuraminidase inhibition assay using 4-MUNANA as a substrate. 相似文献
77.
A precise inference of past demographic histories including dating of demographic events using bayesian methods can only be achieved with the use of appropriate molecular rates and evolutionary models. Using a set of 596 mitochondrial cytochrome c oxidase I (COI) sequences of two sister species of European green crabs of the genus Carcinus (C. maenas and C. aestuarii), our study shows how chronologies of past evolutionary events change significantly with the application of revised molecular rates that incorporate biogeographic events for calibration and appropriate demographic priors. A clear signal of demographic expansion was found for both species, dated between 10,000 and 20,000 years ago, which places the expansions events in a time frame following the Last Glacial Maximum (LGM). In the case of C. aestuarii, a population expansion was only inferred for the Adriatic-Ionian, suggestive of a colonization event following the flooding of the Adriatic Sea (18,000 years ago). For C. maenas, the demographic expansion inferred for the continental populations of West and North Europe might result from a northward recolonization from a southern refugium when the ice sheet retreated after the LGM. Collectively, our results highlight the importance of using adequate calibrations and demographic priors in order to avoid considerable overestimates of evolutionary time scales. 相似文献
78.
Doris Ribitsch Sonja Heumann Eva Trotscha Enrique Herrero Acero Katrin Greimel Regina Leber Ruth Birner‐Gruenberger Sigrid Deller Inge Eiteljoerg Peter Remler Thomas Weber Petra Siegert Karl‐Heinz Maurer Ilaria Donelli Giuliano Freddi Helmut Schwab Georg M. Guebitz 《Biotechnology progress》2011,27(4):951-960
From a screening on agar plates with bis(benzoyloxyethyl) terephthalate (3PET), a Bacillus subtilis p‐nitrobenzylesterase (BsEstB) was isolated and demonstrated to hydrolyze polyethyleneterephthalate (PET). PET‐hydrolase active strains produced clearing zones and led to the release of the 3PET hydrolysis products terephthalic acid (TA), benzoic acid (BA), 2‐hydroxyethyl benzoate (HEB), and mono‐(2‐hydroxyethyl) terephthalate (MHET) in 3PET supplemented liquid cultures. The 3PET‐hydrolase was isolated from non‐denaturating polyacrylamide gels using fluorescein diacetate (FDA) and identified as BsEstB by LC‐MS/MS analysis. BsEstB was expressed in Escherichia coli with C‐terminally fused StrepTag II for purification. The tagged enzyme had a molecular mass of 55.2 kDa and a specific activity of 77 U/mg on p‐nitrophenyl acetate and 108 U/mg on p‐nitrophenyl butyrate. BsEstB was most active at 40°C and pH 7.0 and stable for several days at pH 7.0 and 37°C while the half‐life times decreased to 3 days at 40°C and only 6 h at 45°C. From 3PET, BsEstB released TA, MHET, and BA, but neither bis(2‐hydroxyethyl) terephthalate (BHET) nor hydroxyethylbenzoate (HEB). The kcat values decreased with increasing complexity of the substrate from 6 and 8 (s?1) for p‐nitrophenyl‐acetate (4NPA) and p‐nitrophenyl‐butyrate (4NPB), respectively, to 0.14 (s?1) for bis(2‐hydroxyethyl) terephthalate (BHET). The enzyme hydrolyzed PET films releasing TA and MHET with a concomitant decrease of the water‐contact angle (WCA) from 68.2° ± 1.7° to 62.6° ± 1.1° due to formation of novel hydroxyl and carboxyl groups. These data correlated with a fluorescence emission intensity increase seen for the enzyme treated sample after derivatization with 2‐(bromomethyl)naphthalene. © 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2011 相似文献
79.
Lichtner M Mastroianni CM Rossi R Russo G Belvisi V Marocco R Mascia C Del Borgo C Mengoni F Sauzullo I d'Ettorre G D'Agostino C Massetti AP Vullo V 《PloS one》2011,6(5):e19872
Background
Dysregulation of host immune responses plays a critical role in the pathogenesis of severe 2009 pandemic H1N1 infection. Whether H1N1 virus could escape innate immune defense in vivo remains to be investigated. The aim of this study was to evaluate the pattern of innate immune response during human 2009 H1N1 infection. We performed the enumeration of circulating myeloid dendritic cells (mDC) and plasmacytoid DC (pDC) in blood from patients with H1N1 pneumonia shortly after the onset of symptoms and during follow-up at different intervals of time. The analysis of CD4 and CD8 count, CD38 T-cell activation marker and serum cytokine/chemokine plasma levels was also done.Methodology/Principal Findings
Blood samples were collected from 13 hospitalized patients with confirmed H1N1-related pneumonia at time of admission and at weeks 1, 4, and 16 of follow-up. 13 healthy donors were enrolled as controls. In the acute phase of the disease, H1N1-infected patients exhibited a significant depletion in both circulating pDC and mDC in conjunction with a decrease of CD4 and CD8 T cell count. In addition, we found plasmatic hyperproduction of IP-10 and RANTES, whereas increase in T-cell immune activation was found at all time points. When we assessed the changes in DC count over time, we observed a progressive normalization of mDC number. On the contrary, H1N1-infected patients did not achieve a complete recovery of pDC count as values remained lower than healthy controls even after 16 weeks of follow-up.Conclusions
H1N1 disease is associated with a profound depletion of DC subsets. The persistence of pDC deficit for several weeks after disease recovery could be due to H1N1 virus itself or to a preexisting impairment of innate immunity. 相似文献80.