Search results for "Electrophoresi"
showing 10 items of 1009 documents
Characterisation of a Cryptosporidium parvum-specific cDNA clone and detection of parasite DNA in mucosal scrapings of infected mice.
1998
A cDNA library was constructed using total RNA extracted from oocysts and sporozoites of the protozoan parasite Cryptosporidium parvum. The expression library was screened with an anti-C. parvum antiserum and a clone, Cp3.4, with a 2043 bp insert, was extracted. Southern blot analysis demonstrated a single copy gene that was located on a 1.6 Mb chromosome. The gene was found to be C. parvum specific as Cp3.4 did not cross-hybridise with chromosomal DNA from three other apicomplexan parasites. The cDNA encodes a polypeptide with a predicted membrane helix at its C-terminal end which is flanked by stretches of acidic amino acids. Overall, the polypeptide has a low isoelectric point (pI) of 3.…
Plant progesterone 5β-reductase is not homologous to the animal enzyme. Molecular evolutionary characterization of P5βR from Digitalis purpurea
2007
Plants of the genus Digitalis produce cardiac glycosides, i.e. digoxin, which are widely used for congestive heart failure. Progesterone 5beta-reductase (P5betaR) is a key enzyme in the biosynthesis of these natural products. Here, we have carried out the purification and partial amino acid sequencing of the native P5betaR from foxglove (Digitalis purpurea), and isolated a cDNA encoding this enzyme. Similarly to other steroid 5beta-reductases, the recombinant P5betaR catalyzes the stereospecific reduction of the Delta(4)-double bond of several steroids with a 3-oxo,Delta(4,5) structure. The gene encoding P5betaR is expressed in all plant organs, and maximally transcribed in leaves and matur…
Characterization of a cDNA encoding RP43, a CUB-domain-containing protein from the tube of Riftia pachyptila (Vestimentifera), and distribution of it…
2000
A major 43kDa protein from the protective tube of Riftiapachyptila (Vestimentifera), named RP43, was partly microsequenced after isolation by SDS/PAGE from the protein fraction of tubes collected around the hydrothermal vents at the East Pacific Rise. On the basis of the partial peptide sequences obtained, experiments using reverse-transcriptase-mediated PCR and rapid amplification of cDNA ends led to the complete cDNA sequence. Analysis of deduced amino acid sequence of RP43 showed the presence of CUB domains (100–110-residue-spanning domains first reported in the complement subcomponents C1r/C1s, epidermal-growth-factor-related sea urchin protein and bone morphogenetic protein 1) that se…
Decorin transfection induces proteomic and phenotypic modulation in breast cancer cells 8701-BC
2008
Decorin is a prototype member of the small leucine-rich proteoglycan family widely distributed in the extracellular matrices of many connective tissues, where it has been shown to play multiple important roles in the matrix assembly process, as well as in some cellular activities. A major interest for decorin function concerns its role in tumorigenesis, as growth-inhibitor of different neoplastic cells, and potential antimetastatic agent. The aim of our research was to investigate wide-ranged effects of transgenic decorin on breast cancer cells. To this purpose we utilized the well-characterized 8701-BC cell line, isolated from a ductal infiltrating carcinoma of the breast, and two derived …
Recent advances on ionic liquid uses in separation techniques
2018
International audience; The molten organic salts with melting point below 100°C, commonly called ionic liquids (ILs) have found numerous uses in separation sciences due to their exceptional properties as non molecular solvents, namely, a negligible vapor pressure, a high thermal stability, and unique solvating properties due to polarity and their ionic character of molten salts. Other properties, such as viscosity, boiling point, water solubility, and electrochemical window, are adjustable playing with which anion is associated with which cation. This review focuses on recent development of the uses of ILs in separation techniques actualizing our 2008 article (same authors, J. Chromatogr. A…
Microdisc-electrophoretic study of deoxyribonucleases in cow snout epidermis
1983
Acid and neutral deoxyribonucleases (DNases) of the cow snout epidermis were investigated by the microdisc-electrophoresis of polyacrylamide gels containing highly polymerized DNA and by isoelectric focusing techniques. The nucleases were characterized with respect to their pH optimum. An acid DNase at pH 5.0 was detected as a single distinct band after the electrophoretic separation. After isoelectric focussing also, only one acid DNase activity with an isoelectric point (IP) of 6.2 was detectable. Neutral DNases at pH 7.4 were demonstrated as major and minor bands by their different electrophoretic mobilities. In the isoelectric focusing system also, two neutral DNases, a major one (IP, 4…
Separation of deoxyribonucleases (DNases) of normal human stratum corneum and psoriatic scales by micro-disc-electrophoresis.
1975
Normal stratum corneum and psoriatic scales were homogenized and a differential centrifugation was performed. The DNase activity of the individual fractions was investigated by micro-disc-electrophoresis. At pH 5 only in the 600 × g pellet and 105.000 × g supernatant of normal keratin DNase activity could be observed. However, all psoriatic fractions showed distinct enzyme activities. At pH 7.4 little psoriatic DNase activity could only be demonstrated in the 105.000 × g supernatant. Except from the 15.000 × g pellet all fractions of normal stratum corneum displayed marked activities. In addition the 105.000 × g supernatant showed two different DNase bands.
Capillary electrophoresis for the determination of pesticide residues
2003
Capillary electrophoresis (CE) is becoming an advantageous tool for determining pesticide residues in environmental matrices because of its simplicity and high separation efficiency. However, inadequate limits of detection (LODs) and a lack of selective detectors limit the technique. The present review gives an overview of current developments in off-column and on-column approaches to trace enrichment in analysing real samples, and summarises the determination of pesticides residues by conventional CE as well as by the emerging techniques, such as CE-mass spectrometry (MS). The usefulness of these approaches in environmental applications is documented.
Separation of plutonium and neptunium species by capillary electrophoresis-inductively coupled plasma-mass spectrometry and application to natural gr…
2003
Capillary electrophoresis (CE) was coupled to ICPMS in order to combine the good performance of this separation technique with the high sensitivity of the ICPMS for the analysis of plutonium and neptunium oxidation states. The combination of a fused-silica capillary with a MicroMist AR 30-I-FM02 nebulizer and a Cinnabar small-volume cyclonic spray chamber yielded the best separation results. With this setup, it was possible to separate a model element mixture containing neptunium (NpO2(+)), uranium (UO2(2+)), lanthanum (La3+), and thorium (Th4+) in 1 M acetic acid. The same conditions were also suitable for the separation of various oxidation states of plutonium and neptunium in different a…
Chiral separation of bupivacaine enantiomers by capillary electrophoresis partial-filling technique with human serum albumin as chiral selector
2004
Abstract Capillary electrophoresis (CE) is a powerful technique for enantiomer separations due to its intrinsic high separation efficiencies, speed of analysis, low reagent consumption and small sample requirements. However, some chiral selectors present strong background UV absorption providing high detection limits. The present paper deals with the application of the partial-filling technique to the separation of bupivacaine enantiomers by capillary electrophoresis using human serum albumin (HSA) as chiral selector. In this procedure the cationic surfactant cetyltrimethylammonium bromide (CTAB) was used as a dinamic capillary coating in order to reduce the electro-osmotic flow and detect …