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We have estimated the number of 5S rRNA genes in Aspergillus nidulans using two-dimensional agarose gel electrophoresis and hybridization to appropriate probes, representing the 5'-halves, the 3'-halves of the 5S rRNA sequence and a sequence found at the 3'-end of all known A. nidulans pseudogenes (block C). We have found 23 5S rRNA genes, 15 pseudogenes consisting of the 5'-half of the 5S rRNA sequence (of which 3 are flanked by block C) and 12 copies of block C which do not seem to be in the vicinity of 5S rRNA sequences. This number of genes is much lower than our earlier estimates, and makes our previously analyzed sample of 9 sequenced genes and 3 pseudogenes much more representative.
We report that using the zwitterionic detergent Zwittergent Z 3-14® to isolate outer membrane proteins (OMPs) from Salmonella O48 is suitable for their separation by two-dimensional electrophoresis (2-DE) in a capillary tube system. Sample preparation is a very crucial step for any bacterial proteomic study. Some modifications were introduced to the 2-DE protocol suggested by O'Farrell and BioRad, which significantly impaired the resolution of proteins. 2-DE analysis of OMPs may be helpful in the interpretation of the variable susceptibility of Salmonella O48 rods to the bactericidal activity of serum.
Escherichia coli O56 were originally isolated from infected humans. Here it is reported that using the zwitterionic detergent (Zwittergent Z 3-14®) to isolate outer membrane proteins (OMPs) from Escherichia coli O56 is suitable for their separation by two-dimensional electrophoresis (2-DE) using pH 3-10 immobilized pH gradient IPG strips (BIO-RAD).
Two-dimensional electrophoresis (2-D PAGE) led to identification in the polypeptide maps of boar seminal plasma of four conserved polypeptides with identical molecular weight of 24 kDA, and different ranges of isoelectric point (pI): (1) 7.4-7.7, (2) 8.1-8.4, (3) 8.5-8.8 and (4) 9.2-9.4. In the current study the molecular structures of these polypeptides were analysed, for the first time, by mass spectrometry (LC – MS/MS). Computerized mass spectrometry analysis of the peptides obtained after trypsin-digestion of the polypeptides demonstrated their similarity to the family of spermadhesins (crystal structure of two members of the spermadhesin family), especially to epididymal spermadhesin AWN-1. In addition, homology was found of peptides 3 and 4 with a lysozyme C precursor (1,4-beta-N-acetylmuramidase C). The results presented might indicate the participation of the analysed polypeptides in the processes accompanying fertilization.
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Plasma proteome analysis: 2D gels and chips

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The knowledge of concentration, modification and interaction of proteins is fundamental in determining the phenotype of living organisms. Plasma, the primary clinical specimen, contains numerous and diverse proteins. The functions of these proteins are as manifold as the diversity of the protein themselves. Many of them have been largely used for many years as biomarkers of diseases and indicators of the physiological functions. The study of plasma proteome promises to be a significant advance in various areas of biological and clinical research. Two-dimensional polyacrylamide gel electrophoresis is considered as a primary tool in separating thousand of plasma proteins. This approach enables comparing normal and diseased samples revealing differently expressed proteins. Other proteomic techniques suitable for plasma analysis such as protein microarrays are now either established or are still being improved. This article briefly reviews the application of two-dimensional electrophoresis and the current status of technical aspects for plasma proteome.
Frozen lung tissue sections from 2 healthy and 2 adenocarcinoma affected sheep were lysed in appropriate buffer. The two-dimensional (2D) electrophoresis of the protein lysates was performed. The resulting gels were visualised by silver and Coomassie Blue staining, then scanned and analysed using appropriate software. There was one spot present on the image obtained from the analysis of healthy tissue and no spot was found on cancer 2D gel image. The spot was excised and analysed using mass spectrometry. As a result, cytosolic NADP-isocitrate dehydrogenase was identified. In addition, several other protein spots of different intensity in neoplastic tissues, as compared with healthy ones, were found. The last finding reflects changes in protein expression in neoplastic and healthy tissues. These preliminary results can serve as the basis for more detailed investigations of the neoplastic tissue proteome, e.g.: isoelectric focusing in narrow pH range and analysis of correlation between tissue and serum protein profiles. The analysis of serum proteins from affected sheep can reveal markers of neoplastic process and help in preclinical diagnosis of ovine pulmonary adenocarcinoma.
Two-dimensional electrophoresis (2-DE) of soluble proteins and enzymes was performed and specific activities of 5 enzymes (esterase, pectinesterase, acid phosphatase, protease and diaphorase) were determined in stigmas of Lolium multiflorum (Italian ryegrass) treated with self or foreign pollen coat eluates (pc). Also, a low-molecular-weight fraction of the treated self-compatible (SC) and self-incompatible (SI) stigmas was analyzed by high-pressure liquid chromatography (HPLC). The treatment of stigmas with foreign pollen induced the loss of 42% of the control sample proteins in SC plants but only of 5.5% in SI plants. In contrast, the treatment of stigmas with foreign pollen induced the loss of 15% proteins in SC plants and of 29% in SI plants. Specific activities of esterase, pectinesterase and diaphorase were higher in SC than in SI stigmas. The 2-DE enzyme patterns indicated qualitative relationships between the presence of some isoforms of acid phosphatase or protease and the treatment with self or foreign pc in SC and SI stigmas. No changes were observed in HPLC profiles of the low-molecular-weight fraction from SC and SI stigmas treated or not with pc. The presented results revealed different reactions of SC and SI stigmas to the treatment with self or foreign pc. Further investigations may explain if any of the observed reactions represent specific reorientations in the style, facilitating cross- or self-pollination.
During the early postnatal period in calves various adaptational changes occur. These functional, morphological and also metabolic alteration are reflected by blood plasma protein changes as they are secreted and shed from many cells and tissues. Blood plasma protein pattern of an adult cattle differs in some respect when compared with neonatal calves. There exist a very few data concerning 2-D maps of neonatal calves blood plasma. The above prompted us to establish protein pattern of this biological fluid characteristic of healthy, 7 day old, Polish Black-and-White (Polish Friesian) breed calves. Blood plasma proteins of the isoelectric point ranging from 4.0 to 7.0 were analyzed by the aid of high resolution two-dimensional electrophoresis (2-DE). Subsequently, 79 excised protein spots corresponding to 23 different gene products were identified using matrix-assisted laser desorption/ionisation mass spectrometer (MALDI-TOF MS). Protein map obtained in the present study may be useful in assessing the changes in the calves blood plasma protein profiles occurring in response to different physiological and/or pathophysiological factors.
We wstępie do artykułu przedstawiono stosunkowo nową dziedzinę badań – proteomikę, w obrębie której analizowane są: skład, budowa i funkcja białek oraz zachodzące pomiędzy nimi interakcje. W kolejnych rozdziałach opisano najważniejsze techniki analityczne proteomiki: elektroforezę dwukierunkową, metodę laserowej desorpcji/jonizacji próbki wspomaganej matrycą z analizatorem czasu przelotu (MALDI-TOF) oraz elektrorozpraszanie jonizacyjne (ESI, electrospray ionization). W celu przybliżenia zagadnień związanych z proteomiką w opracowaniu zaprezentowano przykłady analizy proteomu drobnoustrojów, w tym wybranych patogenów (Staphylococcus aureus, Vibrio cholerae, Bacillus subtilis, Mycobacterium avium, Borrelia ssp., Aspergillus flavus). Na podstawie wyników badań proteomu udokumentowano możliwość identyfikacji gatunku oraz badanie metabolizmu mikroorganizmu i interakcji gospodarz–patogen, a nawet możliwość różnicowania potencjału enzymatycznego mikroorganizmów utylizujących surowce ligninocelulozowe. W podsumowaniu zaznaczono potencjał analizy proteomicznej, przydatnej w wielostronnej charakterystyce drobnoustrojów.
The aim of the study is proteomic analysis of the plasma profile in children with recurrent bone fractures. The study involved 16 children: 6 patients with recurrent low-energy fractures and normal bone mass and 10 with osteogenesis imperfecta. In the analysis of the protein profile, the two-dimensional protein electrophoresis was used (Ettan DALT II, Amersham Bioscience). The images of protein gels were compared with controls. The protein spots with changed expression were cut from the gel and the amino acid sequence was analyzed with the mass spectrometry method (Q-Tof PremierTM API MASS SPECTROMETR, Waters) for protein identification. The most prevalent protein with changed expression, with respect to controls, was haptoglobin observed in 6 patients with a severe form of osteogenesis imperfecta. Increased haptoglobin concentration in these patients was confirmed by the ELISA method. Peptides corresponding to alpha-1 acid glycoprotein and serum amyloid P-component, apolipoprotein A-I, and transthyretin were detected in one, two and three children, respectively. Conclusions: 1) The results show increased haptoglobin which may be suggestive of an inflammatory component taking part in the course of osteogenesis imperfecta. 2) Further studies to explain the possible relationship of this protein with increased bone fragility are necessary.
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