purified Protocols

Category: Cell Biology and Cell Culture

Protocol on microtubule assembly using purified tubulin. - [Read Microtubule Assembly Protocol]

Category: Chromatography Protocols: Immobilized Metal Ion Affinity Chromatography Protocols

Protocol for the optimization of imidazole concentrations for immobilized metal-ion affinity chromatography. Most samples from which histidine-tagged proteins are to be purified also contain endogenous protein contaminants that bind to the immobilized metal-ion affinity chromatography (IMAC) adsorbent.  Usually, these proteins bind more weakly than the histidine-tagged protein. - [Read Optimization of Imidazole Concentrations for Immobilized Metal-Ion Affinity Chromatography Protocol]

Category: Chromatography Protocols: Affinity Chromatography Protocols

Protein complexes can be isolated by several different approaches.  For example, a protein can be tagged with an epitope such as Flag or TAP and then overexpressed in a target cell, allowing the interacting proteins to be purified.  Similarly, epitope tags can be homologously recombined into the endogenous locus ("knocked-in"), allowing protein complexes containing the tagged proteins to be isolated at their natural expression level. - [Read Overview of Affinity Purification in Combination with Mass Spectrometry Protocol]

Category: Cytoskeleton Protocols: Microtubules Protocols

The protocol calls for 3 pig brains, and should yield ~ 60 mg of purified tubulin. - [Read Porcine Brain Tubulin Prep Protocol]

Category: Immunology: B Cell Protocols

Procedure permits the isolation of at least 5 µg of total RNA from a sample of purified mouse splenic B lymphocytes. The quality of the RNA is assessed by separation of an aliquot through 1% agarose and staining with ethidium bromide as described in AfCS protocol Visualization of RNA Preparations on 1% Agarose Gels. The isolated RNA is used for analysis of gene expression by microarray technology. analysis of gene expression by microarray technology. - [Read Preparation of B-Lymphocyte RNA for Microarray Analysis Protocol]

Category: Microarray Protocols: Microarray Analysis Protocols

Protocol permits the isolation of at least 5 µg of total RNA from a sample of purified mouse splenic B lymphocytes Isolation of Resting B Lymphocytes from Sixteen Mouse Spleens. - [Read Preparation of B-Lymphocyte RNA for Microarray Analysis Protocol]

Category: Cell Biology and Cell Culture: Flow Cytometry Protocols

A procedure for direct and indirect staining of single-cell suspensions of lymphoid tissue or peripheral blood lymphocytes to detect cell surface membrane antigens is presented. In addition, support protocols present methods for fluorescence labeling of purified antibodies. A protocol for flow cytometric analysis of intracellular antigens in single-cell suspensions is also included. - [Read Preparation of Cells and Reagents for Flow Cytometry Protocols]

Category: Cell Biology and Cell Culture: Endothelial Cell Protocols

Endothelial cells, which line blood vessels, can be prepared from a variety of tissues. They are frequently prepared from the umbilical vein, which is relatively easy to obtain. The procedure is clearly described and provides a large population of highly purified endothelial cells. There are also methods for obtaining endothelial cells from other tissues such as fat, skin, and mucosa. These methods require special care and generate smaller populations of cells. - [Read Preparation of Endothelial Cells Protocol]

Category: Immunology: B Cell Protocols

Describes procedures for measuring the capacity of purified B cells to undergo proliferation. The method centers on the use of polyclonal stimulating agents (mitogens) because these agents stimulate the majority of B cells and because the alternative (measurement of antigen-induced proliferation) requires the laborious procedures of isolating antigen-specific B cells (which are otherwise present in too low a concentration in whole B cell populations). - [Read Proliferative Assays for B Cell Function Protocol]

Category: Cell Biology and Cell Culture

Purified Tubulin is polymerized and then stabilized with Taxol. The resulting Microtubules are then ready for use in motility assays. Protocol use solutions such as 50 mM Mg-GTP, 50 μl 100 mM GTP, 40 μM Taxol, Taxol Stock,and PM Buffer. - [Read Protocol for Microtubule Assembly]

Category: Chromatography Protocols: Affinity Chromatography Protocols

Recombinant proteins, constructed in pGEX vectors, are fused to glutathione S-transferase (GST) and can be purified to near homogeneity by affinity chromatography on glutathione-agarose.  Bound GST-fusion proteins are readily displaced from the column by elution with buffers containing free glutathione. - [Read Purification of Fusion Proteins by Affinity Chromatography on Glutathione Agarose Protocol]

Category: Chromatography Protocols: Affinity Chromatography Protocols

Recombinant proteins engineered to have a polyhistidine tail at either the carboxyl or amino terminus can easily be purified in one step by affinity chromatography on a resin carrying chelated nickel ions.  Chromatography can be carried out in column or batch formats.  After unbound proteins are washed away, the target protein is eluted using imidazole, which typically preserves the antigenic and functional features of the protein. - [Read Purification of Histidine-tagged Proteins by Immobilized Ni2+ Absorption Chromatography Protocol]

Category: Chromatography Protocols: Immobilized Metal Ion Affinity Chromatography Protocols

Histidine-tagged proteins can be purified on prepacked 1-ml immobilized metal-ion affinity chromatography (IMAC) columns without optimization of the separation conditions.  The method allows fast capture of the target protein, although with a lower purity than can be obtained under optimized conditions. - [Read Purification of Histidine-Tagged Proteins Using IMAC Without Parameter Optimization Protocol]

Category: Chromatography Protocols: Affinity Chromatography Protocols

Foreign proteins fused to maltose-binding protein can be readily purified to near homogeneity by affinity chromatography on resins containing cross-linked polysaccharides such as amylose. - [Read Purification of Maltose-binding Fusion Proteins by Affinity Chromatography on Amylose Resin Protocol]

Category: Cell Organelle Protocols: Subcellular Fractionation Protocols

Although Percoll gradients were able to provide a purified sporocyst fraction, because these particles do not all band in a discrete manner in such gradients, they were unable to provide a simultaneous isolation of a pure oocyst wall fraction. Gradients formed from this protocol on the other hand are able to provide purified sporocysts and oocyst walls in the same gradient. - [Read Purification of Oocyst Walls and Sporocysts from Toxoplasma gondii Protocol]

Category: Cell Organelle Protocols: Subcellular Fractionation Protocols: Peroxisome Isolation Protocols

Peroxisomes can be purified in self-generated iodixanol gradients in high yield (80-90%) with no detectable contamination from any other organelle. In iodixanol peroxisomes are the densest of the major subcellular organelles (ρ = 1.18-1.20 g/ml) present in the light mitochondrial fraction from mammalian tissues and cells. - [Read Purification of Peroxisomes in a Self-Generated Gradient]

Category: Cell Organelle Protocols: Subcellular Fractionation Protocols: Peroxisome Isolation Protocols

Peroxisomes can be purified in iodixanol gradients in high yield (80-90%) with no detectable contamination from any other organelle. This is a property unique to iodixanol because the densities of other organelles, particularly that of mitochondria (approx ρ = 1.14 g/ml) and endoplasmic reticulum (approx ρ = 1.13 g/ml) are much lower than that of peroxisomes (approx ρ = 1.18 g/ml). - [Read Purification of Peroxisomes using a Density Barrier in a Swinging-Bucket Rotor]

Category: Nucleic Acid Purification Protocols: RNA Isolation Protocols: RNA Isolation fromTissues or Cultured Cells Protocols

Single-step technique, cells are homogenized in guanidnium thiocyanate and the RNA is purified from the lysate by extraction with phenol:chloroform at reduced pH.  Many samples can be processed simultaneously and speedily.  The yield of total RNA depends on the tissue or cell source and is generally in the range of 4-7 µg/ml starting tissue or 5-10 µg/106 cells.  IMPORTANT: Prepare all reagents used in this protocol with Diethyl pyrocarbonate (DEPC)-treated H2O. - [Read Purification of RNA from Cells and Tissues by Acid Phenol-Guanidinium Thiocyanate-Chloroform Extract]

Category: Nucleic Acid Electrophoresis Protocols: DNA Electrophoresis Protocols: DNA Electrophoresis in Polyacrylamide Gels Protocols

Protocol for purification of synthetic oligonucleotides by polyacrylamide gel electrophoresis. As a rule of thumb, oligonucleotides >25 nucleotides should be purified by polyacrylamide gel electrophoresis, as should oligonucleotides of any length that yield anomalous results.  After electrophoresis, the oligonucleotide is eluted from the gel and concentrated by reversed-phase chromatography on Sep-Pak C18 columns. - [Read Purification of Synthetic Oligonucleotides by Polyacrylamide Gel Electrophoresis Protocol]

Category: Yeast Protocols: Yeast Genetics Protocols: YACs Protocols

Protocol describes a method for purification of YAC DNA using ultrafiltration. This is the fastest method available, but care needs to be taken not to damage the DNA. The purified DNA can then be used for microinjection. - [Read Purification of Yeast Artificial Chromosome (YAC) DNA with Filtration Units Protocol]

Category: DNA Protocols: DNA Extraction Protocols: Agarose Gel DNA Extraction Protocols

Rapid Elution of DNA Agarose Gels Protocol.  This method allows quick purification of DNA fragments from agarose gels for use in cloning and other reactions. Higher yields of purified DNA can be obtained from commercially available purification kits, however greater ligation efficiencies per given amount of DNA have been seen with the use of these described spin columns. Hahn Lab. - [Read Rapid Elution of DNA Agarose Gels Protocol]

Category: PCR Protocols: Real-Time PCR Protocols

Protocol uses the Superscript II First-Strand Synthesis system for the generation of cDNA from total RNA.  RNA purified using TRIzol reagent (Invitrogen) or the methods described in Preparation of RNA Using Guanidinium Isothiocyanate/Cesium Chloride Ultracentrifugation, Preparation of RNA from Paraffin-Embedded Fixed Tissue. - [Read Real-Time RT-PCR: cDNA Synthesis Protocol]

Category: PCR Protocols: Reverse Transcriptase RT-PCR Protocols

Protocol uses the Superscript II First-Strand Synthesis system for the generation of cDNA from total RNA.  RNA purified using TRIzol reagent (Invitrogen) or the methods described in Preparation of RNA Using Guanidinium Isothiocyanate/Cesium Chloride Ultracentrifugation, Preparation of RNA from Paraffin-Embedded Fixed Tissue. - [Read Real-Time RT-PCR: cDNA Synthesis Protocol]

Category: Nucleic Acid Electrophoresis Protocols: DNA Electrophoresis Protocols: DNA Electrophoresis in Agarose Gels Protocols

A fragment of gel containing a band of DNA is excised and digested with agarase, which hydrolyzes the polymer to disaccharide subunits.  The released DNA is then purified by phenol extraction and ethanol precipitation.  The method works well for DNAs ranging in size from <5 kb to >20 kb. - [Read Recovery of DNA from Low-melting-temperature Agarose Gels: Enzymatic Digestion with Agarase Protocol]

Category: Nucleic Acid Electrophoresis Protocols: Pulsed Field Gel Electrophoresis Protocols

Protocol for retrieval of DNA fragments from pulsed-field gels following DNA concentration. DNA contained in a slice of low-melting-temperature agarose is first concentrated by electrophoresis into a high-percentage agarose gel, and then isolated by treatment with agarase.  The resulting DNA preparation is purified by microdialysis. - [Read Retrieval of DNA Fragments from Pulsed-field Gels following DNA Concentration Protocol]