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51.
Duranti M Barbiroli A Scarafoni A Tedeschi G Morazzoni P 《Protein expression and purification》2003,30(2):167-170
A fast and simple method for the extraction and purification of Kunitz trypsin inhibitor from soybean seeds is described. The first step consisted in the heat treatment of whole soybean seeds in water at 60 degrees C for 90 min. It was found that 8.4% of total trypsin inhibitory activity of the seeds was secreted during heat treatment. The aqueous medium was loaded onto an affinity chromatography column with immobilized trypsin. The retained fraction, eluted with 0.01 N HCl, contained the purified Kunitz trypsin inhibitor, which was subsequently stabilized by freeze-drying without loss of activity. From 1g soybean seeds, 0.7 mg inhibitor with a specific trypsin inhibitory (TI) activity of 11,430 TIU/mg was obtained. The yield was greater than that obtained with established procedures. Due to the ease of the procedure proposed, the method is readily scalable to pilot plant or industrial preparations. 相似文献
52.
Mechanism of constitutive export from the golgi: bulk flow via the formation,protrusion, and en bloc cleavage of large trans-golgi network tubular domains 下载免费PDF全文
Polishchuk EV Di Pentima A Luini A Polishchuk RS 《Molecular biology of the cell》2003,14(11):4470-4485
Transport of constitutive cargo proteins from the Golgi complex to the plasma membrane (PM) is known to be mediated by large tubular-saccular carriers moving along microtubules. However, the process by which these large structures emerge from the trans-Golgi network (TGN) remains unclear. Here, we address the question of the formation of Golgi-to-PM carriers (GPCs) by using a suitable cluster of morphological techniques, providing an integrated view of their dynamics and three-dimensional structure. Our results indicate that exit from the TGN of a constitutive traffic marker, the VSVG protein, occurs by bulk flow and is a three-step process. First, the formation of a tubular-reticular TGN domain (GPC precursor) that includes PM-directed proteins and excludes other cargo and Golgi-resident proteins. Notably, this step does not require membrane fusion. Second, the docking of this preformed domain on microtubules and its kinesin-mediated extrusion. Finally, the detachment of the extruded domain by membrane fission. The formation of GPCs does not involve cargo concentration and is not associated with the presence of known coat proteins on GPC precursors. In summary, export from the Golgi occurs via the formation, protrusion and en bloc cleavage of specialized TGN tubular-saccular domains. 相似文献
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The effect of an in vivo and in vitro treatment with cadmium on transport activities of root plasma membrane enriched vesicles was studied in oat (Avena sativa L. cv. Argentina) plants. Addition of 100 mumol/L CdSO4 to nutrient solution decreases both proton transport activity and ATPase activity to the same level. In vitro experiments show that cadmium seems to have a differential inhibiting effect on proton transport activity and ATPase activity, the most pronounced one on ATP-dependent H(+)-accumulation, suggesting that cadmium would interfere with membrane permeability properties. This is indeed the case. The results demonstrate that cadmium decreases passive permeability to protons. 相似文献
55.
Double muscling in Marchigiana beef breed is caused by a stop codon in the third exon of myostatin gene 总被引:10,自引:0,他引:10
Cinzia?MarchitelliEmail author Maria?Carmela?Savarese Alessandra?Crisà Alessandro?Nardone Paolo?Ajmone?Marsan Alessio?Valentini 《Mammalian genome》2003,14(6):392-395
Double muscling is a partially recessive trait present in some beef breeds. It shows a high frequency in some breeds, while in others the frequency is low, and double-muscled individuals are rare. The double muscling is caused by an allelic series of mutations that cause a loss of function of the myostatin gene ( GDF8). We describe here a new mutation in the myostatin gene in Marchigiana breed, a typical beef breed of Central Italy, in which rare double-muscling individuals have been described. A PCR product of the third exon was sequenced in subjects phenotypically showing double muscling, and a G > T transversion was discovered that introduces a premature stop codon. The variant found adds to the large series of mutations present in cattle, and particularly to the only two causative of double muscling in the third exon. A PCR-RFLP test is described for the rapid and effective identification of both heterozygous and homozygous subjects. It was applied to a larger survey carried on the same and also in two other beef breeds, Chianina and Romagnola. Further individuals carrying the new variant were found in Marchigiana, but none in the other breeds. The results may be important for a better comprehension of the role of myostatin in muscular development, for commercial use and for the inference of phylogeny of this gene. 相似文献
56.
Francesca Catanzano Giuseppe Graziano Valeria Cafaro Giuseppe D’Alessio Alberto Di Donato Guido Barone 《International journal of biological macromolecules》1998,23(4):277-285
Four residues Pro19, Leu28, Cys31 and Cys32 proved to be the minimal structural requirements in determining the dimeric structure and the N-terminal segment swapping of bovine seminal ribonuclease, BS-RNase. We analyzed the content of secondary and tertiary structures in RNase A, P-RNase A, PL-RNase A, MCAM-PLCC-RNase A and MCAM-BS-RNase, performing near and far-UV CD spectra. It results that the five proteins have very similar native conformations. Thermal denaturation at pH 5.0 of the proteins, studied by means of CD measurements, proved reversible and well represented by the two-state ND transition model. Thermodynamic data are discussed in the light of the structural information available for RNase A and BS-RNase. 相似文献
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Genomic Resources Development Consortium Mariella Baratti Federica Cattonaro Tiziana Di Lorenzo Diana Maria Paola Galassi Valentina Iannilli Alessio Iannucci Just Jensen Peter Foged Larsen Rasmus O. Nielsen Cino Pertoldi Dragos Postolache Jose Martin Pujolar Ettore Randi Aritz Ruiz‐Gonzalez Janne Pia Thirstrup Giovanni Giuseppe Vendramin Andrzej Zalewski 《Molecular ecology resources》2015,15(2):458-459
59.
Alexander Domnich Donatella Panatto Alessio Signori Piero Luigi Lai Roberto Gasparini Daniela Amicizia 《PloS one》2015,10(5)
BackgroundWeb queries are now widely used for modeling, nowcasting and forecasting influenza-like illness (ILI). However, given that ILI attack rates vary significantly across ages, in terms of both magnitude and timing, little is known about whether the association between ILI morbidity and ILI-related queries is comparable across different age-groups. The present study aimed to investigate features of the association between ILI morbidity and ILI-related query volume from the perspective of age.MethodsSince Google Flu Trends is unavailable in Italy, Google Trends was used to identify entry terms that correlated highly with official ILI surveillance data. All-age and age-class-specific modeling was performed by means of linear models with generalized least-square estimation. Hold-out validation was used to quantify prediction accuracy. For purposes of comparison, predictions generated by exponential smoothing were computed.ResultsFive search terms showed high correlation coefficients of > .6. In comparison with exponential smoothing, the all-age query-based model correctly predicted the peak time and yielded a higher correlation coefficient with observed ILI morbidity (.978 vs. .929). However, query-based prediction of ILI morbidity was associated with a greater error. Age-class-specific query-based models varied significantly in terms of prediction accuracy. In the 0–4 and 25–44-year age-groups, these did well and outperformed exponential smoothing predictions; in the 15–24 and ≥ 65-year age-classes, however, the query-based models were inaccurate and highly overestimated peak height. In all but one age-class, peak timing predicted by the query-based models coincided with observed timing.ConclusionsThe accuracy of web query-based models in predicting ILI morbidity rates could differ among ages. Greater age-specific detail may be useful in flu query-based studies in order to account for age-specific features of the epidemiology of ILI. 相似文献
60.
Verbascoside down‐regulates some pro‐inflammatory signal transduction pathways by increasing the activity of tyrosine phosphatase SHP‐1 in the U937 cell line 下载免费PDF全文
Mirko Pesce Sara Franceschelli Alessio Ferrone Maria Anna De Lutiis Antonia Patruno Alfredo Grilli Mario Felaco Lorenza Speranza 《Journal of cellular and molecular medicine》2015,19(7):1548-1556
Polyphenols are the major components of many traditional herbal remedies, which exhibit several beneficial effects including anti‐inflammation and antioxidant properties. Src homology region 2 domain‐containing phosphatase‐1 (SHP‐1) is a redox sensitive protein tyrosine phosphatase that negatively influences downstream signalling molecules, such as mitogen‐activated protein kinases, thereby inhibiting inflammatory signalling induced by lipopolysaccharide (LPS). Because a role of transforming growth factor β‐activated kinase‐1 (TAK1) in the upstream regulation of JNK molecule has been well demonstrated, we conjectured that SHP‐1 could mediate the anti‐inflammatory effect of verbascoside through the regulation of TAK‐1/JNK/AP‐1 signalling in the U937 cell line. Our results demonstrate that verbascoside increased the phosphorylation of SHP‐1, by attenuating the activation of TAK‐1/JNK/AP‐1 signalling. This leads to a reduction in the expression and activity of both COX and NOS. Moreover, SHP‐1 depletion deletes verbascoside inhibitory effects on pro‐inflammatory molecules induced by LPS. Our data confirm that SHP‐1 plays a critical role in restoring the physiological mechanisms of inducible proteins such as COX2 and iNOS, and that the down‐regulation of TAK‐1/JNK/AP‐1 signalling by targeting SHP‐1 should be considered as a new therapeutic strategy for the treatment of inflammatory diseases. 相似文献