You are currently browsing the archives for the Technical Note category.

Archive for the ‘Technical Note’ Category

How to generate milligram quantities of protein in under 120 minutes

 :: Posted by American Biotechnologist on 03-18-2010

Affinity purification of protein is a common technique in most protein labs which is often the bottle neck in achieving faster experimental results. The technique usually involves the use of HIS or GST tags which need to be enzymatically cleaved from of the recombinant protein in a laborious and time-consuming process so as not to interfere with the protein’s functional activity or crystallization process. Furthermore, many functional assays and crystallography experiments require large amounts of protein which can be frustrated by the drawn-out purification/tag cleavage process.

In this technical note, Justin L. Burns et. al. from the Georga Insitute of Technology report how the combination of the Profinity eXact fusion-tag and Profinia automated purification system allowed them to recover milligram quantities of protein from a gram-negative bacteria in under 2 hours.

Purify Protein in Under 120 Minutes

An Ideal Fluorescent Stain for Proteomics Research

 :: Posted by American Biotechnologist on 03-16-2010

In order to be useful in proteomics applications, a fluorescent stain must be sensitive enough to visualize protein quantities down to 1 ng or less, exhibit minimal protein-to-protein variability in staining intensity and fully compatible with 2D electrophoresis and mass spectrometric fingerprinting.

In this study, the performance of Bio-Rad’s Oriole gel stain is characterized with respect to its spectral properties, detection sensitivity, protein-to-protein variability and compatibility with mass spectrometry. Furthermore, the study describes how Oriole may be imaged using UV light which is ideal considering that UV-based imaging equipment is relatively simple and inexpensive and tends to be more generally available to laboratory researchers.

Oriole Fluorescent Gel Stain: Characterization with SYPRO Ruby Gel Stain

How to Enrich Serum Proteins for BioMarker Discovery

 :: Posted by American Biotechnologist on 03-08-2010

Plasma and Serum are often used in biomarker discovery studies because they are easy to obtain from patients and are readily available. The biggest challenge with using these sources in biomarker studies is the HUGE overexpression of approximately 20 predominant proteins such as heat shock proteins and albumin (to name a few) which represent about 99% of the total protein mass. Since most analytical technologies are incapable of resolving expression levels over more than 5 orders of magnitude, proteins with low expression levels (which are most likely to be viable candidates for biomarker studies since differences in their expression levels between normal and diseased states are more easily resolved) are often masked and difficult to detect.

Unfortunately, many of the technologies available which aid in biomarker discovery rely on the depletion of high abundance proteins which often ends up depleting low abundant proteins as well thereby “throwing out the baby with the bathwater.”

Bio-Rad has recently launched a new and innovative method for resolving differences in low abundant proteins using a unique quantitative enrichment technology.

In the article “Quantitation of Serum and Plasma Proteins After Enrichment of Low-Abundance Proteins With the ProteoMiner Protein Enrichment System” you will discover how Proteominer is the ideal technology for anyone using serum or plasma for biomarker discovery.

A gel worthy of high-impact publication

 :: Posted by American Biotechnologist on 03-02-2010

Yes…SDS PAGE is boring. But it’s an indispensable part of our bench research. We put tons of time into designing experiments, sample prep and playing video games (oops…Freudian slip). It is therefore absolute torture when we load our precious sample into a gel, run it for 30 to 60 minutes only to discover that the quality of the gel has significantly compromised what promised to be an award winning figure worthy of publication in the likes of Nature or Science (would you even think of publishing anywhere else?).

For as long as I can remember, Bio-Rad has been at the forefront of electrophoresis technology. There is hardly a graduate student out there who has not come across a green MP3 or MP tetra electrophoresis unit during the course of their graduate work. Now Bio-Rad has released a new SDS Polyacrylamide Gel that provides high resolution separation regardless of the origin or complexity of the sample. Moreover, whether you are a 2-D researcher, a “stainer” or a run of the mill 1D separation type of scientist, the new TGX gels will help you produce results that your reviewers will be proud of! See the tech note for more details.