prepared Protocols

Category: Protein Protocols: Protein Quantitation Concentration Protocols

Absorbance assays are fast and convenient, since no additional reagents or incubations are required.  No protein standard need be prepared.  The assay does not consume the protein.  The relationship of absorbance to protein concentration is linear.  Because different proteins and nucleic acids have widely varying absorption characteristics there may be considerable error, especially for unknowns or protein mixtures. - [Read Absorbance Assay 280 nm]

Category: Reporter Gene Assays: B-Galactosidase Assay Protocols

Method describes how a crude extract is prepared, and the activity is normalized to the amount of protein assayed. This method is particularly suitable for comparing cells that are grown under very different conditions or that have different genetic backgrounds. - [Read Assay of ß-Galactosidase in Yeast: Assay of Crude Extracts]

Category: Yeast Protocols: Yeast Genetics Protocols: B-Galactosidase Assay Protocols

Protocol describes how a crude extract is prepared, and the activity is normalized to the amount of protein assayed. This method is particularly suitable for comparing cells that are grown under very different conditions or that have different genetic backgrounds. - [Read Assay of ß-Galactosidase in Yeast: Assay of Crude Extracts Protocol]

Category: Cytogenetics Protocols: DIG Biotin Labeled Probe Protocols

This protocol describes how to use DIG Chem-Link to directly label any DNA [e.g. plasmids, PCR products, cDNA prepared from mRNA] or RNA (e.g. total RNA, poly(A)+ mMRNA). The DIG Chem-Link or Biotin Chem-Link may also be used to label oligonucleotides. Includes: Required Purity of DIG Chem-Link Templates; Direct DIG Labeling of mRNA or cDNA with DIG Chem-Link; Key Product Required for Direct Labeling of DNA or RNA; Estimating the Yield of DIG-labeled Nucleic Acids. - [Read Chem-Link Labeling of DNA or RNA with DIG or Biotin Protocol]

Category: Viral Manipulation Protocols: M13 Phage Manipulation Protocols

Protocol describes three standard methods to construct bacteriophage M13 recombinants: (1) ligating insert DNA to a linearized vector, prepared by cleavage of M13 RF with a single restriction enzyme; (2) using alkaline phosphatase to suppress self-ligation of the linearized vector, and (3) using M13 RF cleaved with two restriction enzymes for directional cloning. - [Read Cloning into Bacteriophage M13 Vectors Protocol]

Category: PCR Protocols: Reverse Transcriptase RT-PCR Protocols

The first step in competitive RT-PCR is the synthesis and purification of the synthetic competitor.  This is an RNA molecule designed to be reverse-transcribed and PCR-amplified with the same efficiency as the endogenous transcript of interest.  Once the competitor molecule has been prepared, as described in this protocol, competitive PCR can be carried out. - [Read Competitive RT-PCR: Preparation of Competitor RNA Protocol]

Category: Chromatography Protocols: DNA RNA Affinity Chromatography

DNA Affinity Chromatography, DNA affinity chromatography can be a low-tech method using gravity flow at 4°C, a disposable chromatography column, and DNA affinity resin prepared in the laboratory (see Preparation of a DNA Affinity Column). Include 10-20% glycerol and 0.025-0.1% NP-40 in the column buffers to suppress losses due to nonspecific adsorption of protein to surfaces. Load the protein in a buffer that is compatible with binding of the protein to its target site. Keith Brocklehurst et al - [Read DNA Affinity Chromatography Using Gravity Flow - Subscription Required]

Category: Protein Protocols: Protein Precipitation Procols

ENZYME PURIFICATION BY SALT (AMMONIUM SULFATE) PRECIPITATION. Prepared by Nam Sun Wang, Department of Chemical & Biomolecular Engineering. University of Maryland. - [Read Enzyme Purification by Salt Ammonium Sulfate Precipitation]

Category: Bacterial Cell Culture Protocols: Bacterial Cell Culture Media Protocols

This protocol has been used successfully to 15N or 13C/15N label our proteins using our pET1120/BL21(DE3) expression system: Preparing M9 minimal media begins with preparing a 5x stock solution of M9 salts. Generally, M9 salts contain a nitrogen source in the form of NH4Cl. Since we want to add a labeled nitrogen source, our 5x salts are prepared minus NH4Cl. Standard 5 X M9 Minimal Media salts minus nitrogen source For 1L 5xM9 salts: - [Read Expression Protocol in M9 Minimal Media via T7 Promoter]

Category: Molecular Imaging: Electron Microscopy Protocols

In brief, the reaction mixture, is prepared in exactly the same way as if the sample is to be stained or shadowed for electron microscopy, but once the... Gold labeling technique for electron microscopic identification and location of proteins. - [Read Gold labeling of proteins for electron microscopy]

Category: Competent Cells Protocols

This is an easy and straightforward protocol that gives efficiencies of 106 to 107 cfu/mg of plasmid DNA.  A growth curve is required for each strain that is prepared.
- [Read High Efficiency FCC Preparation and Tx Protocol]

Category: Pharmacology and Toxicology Protocols: Drug Discovery

High-throughput and sensitive assay to measure yeast cell growth: a bench protocol for testing genotoxic agents. Method is highly sensitive, provides quantifiable data and offers high-throughput screening capability.  Starting with the treatment of cells with different doses of damaging agents, pre-prepared growing media containing 96-well plates are inoculated and cell population is automatically monitored every 10 min for 48 hours.  - [Read High Throughput and Sensitive Assay Measure Yeast Cell Growth Protocol]

Category: Western Blot Protocols: General Western Blot Methods Protocols

Protocol describes how proteins are mixed with a sample buffer and prepared for electrophoresis on standard Tris/glycine SDS-polyacrylamide gels. - [Read Immunoblotting: Preparing Protein Solutions Protocol]

Category: Microinjection Protocols: Microinjection of Proteins Protocols

Activation and inactivation of proteins using photoactivation of caged peptides or proteins offer insights into cellular dynamics not achievable using genetic means. The ability to selectively alter the activity of a specific protein at a defined time and location inside a cell allows the correlation of changes in protein activity and cellular behavior. A caged compound, peptide, or protein is prepared by covalently linking it to a photolabile, protecting group. - [Read Introduction of Caged Peptide/Protein into Cells Using Microinjection Protocol]

Category: BACs Bacterial Artificial Chromosome Protocols

BAC DNAs are prepared from 5-ml cultures of BAC-transformed cells by a modification of the standard alkaline lysis method (Preparation of Plasmid DNA by Alkaline Lysis with SDS: Minipreparation). The yield typically varies between 0.1 and 0.4 µg of BAC DNA. - [Read Isolation of BAC DNA from Small-scale Cultures Protocol]

Category: Primary Cell Isolation and Culture Protocols: Laser Capture Microdissection Protocols

LCM utilizes an infrared laser integrated into a standard microscope. A transparent cap is attached to a thermoplastic transparent membrane which lies directly on the surface of a routinely prepared tissue section on a glass slide. The investigator examines the tissue section microscopically and activates the laser when the desired cells underlie the target. This in turn activates the membrane with subsequent binding and procurement of the cells of interest. - [Read Laser Capture Microdissection (LCM)]

Category: Lipid Protocols

Protocol for lipid extraction from plasma membrane fractions prepared from yeast cells. - [Read Lipid Extraction from Plasma Membrane Fractions Prepared from Yeast Cells Protocol]

Category: Viral Culture and Isolation Protocols: Viral Culture Protocols

5 ml liquid lysates are prepared when a small amount of DNA from a large number of lambda clones is needed. The lysates can be made using 10- 20 ul of a stock lysate or a 100-fold amplified phage "macroplaque" as the inoculum. - [Read Liquid Phage Lysates Protocol]

Category: Reporter Gene Assays: Cat Assays Protocols

In this protocol, extracts prepared from cells transfected with a chloramphenicol acetyltransferase (CAT) reporter plasmid are incubated with radiolabeled chloramphenicol. The acetylated products generated by the action of CAT are separated from the unmodified drug by thin-layer chromatography and quantitated by scraping the spots from the thin-layer plates and counting them by scintillation spectroscopy. - [Read Measurement of CAT in Extracts of Mammalian Cells Using Thin-layer Chromatography]

Category: PCR Protocols: cDNA Synthesis Protocols

In MOPAC, the amino-terminal and carboxy-terminal sequences of a peptide are used to design two redundant families of oligonucleotides encoding the aminoand carboxy-terminal sequences of the peptide.  The primers are used either to amplify a segment of cDNA prepared by RT-PCR from a tissue known to express the protein or to amplify a segment of DNA from an established genomic or cDNA library. - [Read Mixed Oligonucleotide-primed Amplification of cDNA MOPAC Protocol]

Category: PCR Protocols

DNA prepared by PCR-mediated gene disruption can be used to transform yeast in gene replacement experiments.  This protocol uses two primers, tailed with approximately 50 nucleotides homologous to the gene of interest, that target insertion of the PCR product to that locus.  Each primer ends with a universal sequence that is designed to amplify various selectable markers from plasmid templates. - [Read PCR-Mediated Gene Disruption: One-Step Method Protocol]

Category: Viral Manipulation Protocols: Phage Lamda Manipulation Protocols

Bacteriophage {lambda} vectors that allow genetic selection of recombinant bacteriophages (e.g., the EMBL series, {lambda}2001, {lambda}DASH, {lambda}ZAP, and {lambda}gt10) can be prepared for cloning by simple digestion by one or more restriction enzymes. - [Read Preparation of Bacteriophage lambda DNA Cleaved with a Single Restriction Enzyme Protocol]

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

Protocol for preparation of DNA for pulsed-field gel electrophoresis: isolation of DNA from mammalian cells and tissues. Genomic DNAs from mammalian cells are prepared for pulsed-field gel electrophoresis by lysing cells in situ in an agarose plug.  Following digestion with an appropriate restriction enzyme, the plug is loaded directly into the well of a pulsed-field gel or it can be melted before loading. - [Read Preparation of DNA for Pulsed-field Gel Electrophoresis: Isolation of DNA from Mammalian Cells]

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: Stem Cell Protocols: Feeder Cell Preparation Protocols

MEF feeders are prepared weekly to provide a substrate for undifferentiated embryonic stem (ES) cells. Primary MEF cells are thawed, established in culture, treated with mitomycin C to halt their proliferation so they cannot overgrow the ES cultures, and then replated onto dishes convenient for ES cell culture. This protocol can also be used to prepare feeder cells from STO fibroblast cell lines. - [Read Preparation of Mouse Embryonic Fibroblast (MEF) Feeder Plates Protocol]