:: Posted by American Biotechnologist on 11-15-2011
Protein blotting is a staple technique of most molecular biology and proteomics laboratories. In previous posts, we discussed topics such as semi-dry protein transfer and protein transfer methods, and we even did a multi-part series on western blotting.
Now, we are proud to present you with a 43 page protein blotting guide put together by Bio-Rad Laboratories. The guide is organized into two parts which cover the theory and methods behind protein blotting. You will learn topics such as methods and instrumentation, the difference between various membranes and tranfer buffers, the ins and outs of transfer conditions, detection and imaging and a host of different blotting and detection protocols.
The guide is fairly technical and is appropriate for both novice and advanced users alike.
Click on the link to download the Protein Blotting Guide now.
:: Posted by American Biotechnologist on 11-10-2011
Angiogenesis is a fundamental process required for multiple physiological and pathological events. It is also a hallmark of over 50 different disease states, including cancer, rheumatoid arthritis, cardiovascular diseases, diabetes and psoriasis. Methods developed to study these diseases are important tools for testing potential therapeutics. These methods include both in vivo and in vitro assays. In vivo assays are considered the most informative because of the complex nature of vascular responses to test reagents. However these assays are often costly and laborious. In contrast, in vitro assays can be carried out expeditiously, are less expensive, and are easier to interpret. Often, these in vitro assays provide maximum benefits when developed as multivariate index assays where the data of multiple assays yield a composite profile of clinically relevant protein biomarkers.
Bio-Rad has developed a multiplex Bio-Plex Pro human cancer biomarker panel that measures angiogenesis biomarker in diverse matrices including serum, plasma, cell culture supernatant and many other sample types. Using this assay, it is possible to quantify multiple angiogenesis targets n a single well of a 96-well microplate in just three hours, using as little as 12.5ul of serum or plasma.
To read more see the attached technical note.
:: Posted by American Biotechnologist on 11-08-2011
We have posted several times in the past about the fun and constructive online game Foldit! that helps gamers contribute important information to a protein structure database while playing a fun video game. We called it “guilt free computer gaming.” (See our previous posts Crowdsourcing as a model for protein structure discovery and Foldit! Guilt-Free Computer Gaming for Protein Scientists).
Read the rest of this entry »
:: Posted by American Biotechnologist on 11-03-2011
Here are some great application tips from Bio-Rad Laboratories for those researchers working with proteins:
- Generally, the best method for keeping a protein in solution is to add any combination of nonionic detergents, zwitterionic detergents, and chaotropic agents to the sample mixture. Also use reducing agents such as DTT and DTE (less than 20 mM) to decrease disulfide bond formation between proteins.
- When working with membrane or insoluble proteins, increase the amount of SDS in the equilibration and running buffers (up to 0.2%) to allow the proteins to effectively migrate out of the IPG strip.
- To reduce the amount of SDS in samples generated by preparative SDS-PAGE, substitute the elution buffer with one that does not contain SDS.
- Nucleic acid contamination is a common cause of horizontal gel streaking. Treat samples with nucleases to remove nucleic acids prior to isoelectric focusing.
- Never heat samples in urea-containing buffers. The urea rapidly breaks down to carbamic acid and carbamylates the proteins, modifying their charge. Urea breakdown and subsequent protein carbamylation is the cause of charge trains on 2-D gels. A charge train is a series of spots on a 2-D gel that are of different pIs and the same size.
For more great tips visit www.expressionproteomics.com
:: Posted by American Biotechnologist on 11-01-2011
Proteins are literally the movers and the shakers of the intracellular world. If DNA is the film director, then they are the actors. And much can be learned about cell function – and dysfunction – by watching proteins on the move.
Until now, scientists have only been able to see this process indirectly. Now researchers at Vanderbilt University in Nashville, Tenn., have come up with a promising new technique that uses a scanning transmission electron microscope (STEM) to view proteins tagged with gold nanoparticles in whole, intact cells.
Read the rest of this entry »