The larger the molecule, the more frequently it remains in the pores of the gel,

I have probably already poured hundreds of gels and run - the electrophoresis of biomolecules is for me the standard laboratory method par excellence. Nevertheless, lysozyme she always provides surprises. lysozyme A riddle daily laboratory, which I have not yet been solved, there's at the end of this post.
("Worn" is inserted in Greek. Phoresis,) The basic principle of electrophoresis, which is pretty easy. Charged particles - such as DNA - migrate in an electric field: positively charged particles to the negatively lysozyme charged cathode, and negatively charged particles to the positively charged anode. Placing the particles in some way, such as a molecular sieve in the form of a gel, then they are hindered in their movement.
The larger the molecule, the more frequently it remains in the pores of the gel, "hang", and the slower it moves also. Smaller particles move faster therefore. So come the famous images of "genetic fingerprints" into existence - each strip ("gang") stands for a lot of DNA molecules of a certain length. The more intense the band, the more DNA it contains. I'll currently prefer proteins migrate, I'm glad I nucleic acids for the time being (?)'ve Left behind me. Ulrich Laemmli, this method has almost perfected with a novel buffer system and in the Caption here (!) Described a 1970 published Nature article. The article in which it actually comes to bacteriophages, counts with more than 167,000 citations of the most cited papers ever! Leaving a "modern" run minigel, then it looks like in this time lapse video:
The blue dye that moves there, only to make the most colorless sample easier pipettable serves. lysozyme The proteins and the actual subjects of the experiment must be colored separately later. But if you look closely, you can see on the right edge a narrow set of colored bands that separate slowly. These are already lysozyme pre-stained proteins that are used as standard, as compared to its unknown proteins.
In the above black and white image you see on the left the ladder of standard proteins, lysozyme and the right one protein extract with all kinds of impurities and my protein which is present in such high concentration that the band swells beyond its borders. Based on the standard head left I can see that it is about 11 kilodaltons in size. Now this is not a particularly nice example, but how it can go awry, demonstrates the Hall of Shame of the protein gels by David R. Caprette. lysozyme
In the video at the top you can see that there is also a faint band runs along a ghostly, slightly faster than the actually blue bromophenol blue (see right). The color of bromophenol blue is dependent on the pH-value: In the acidic environment it is yellow in the neutral and alkaline range is blue. The faster moving bands may represent lysozyme different charged species of bromophenol blue, which does not fit with the color change toward yellow at higher protonation. From purple and pink I have read anywhere.
Costs? Do you like me for my money list and science: 14 orders of magnitude say how much gel electrophoresis cost? Both the apparatus and a single gel? Karl Bednarik July 29, 2011 7:07 Reply | Permalink
My proud works: lysozyme
Thank you for your input! So fresh the buffer is no longer, so it would be quite possible that the bromophenol blue has since been modified. NMR spectrometer we have to satisfy, but I have not cut the bands, but the gel fixed and stained. And I was able to reproduce it yet more, the above gel was probably lysozyme due to an error on my part a smaller pore size - have or I have provided from another buffer.
The Krl from above horizontal running gels are cheaper. For the SDS-PAGE is also still needs casting station, glass plates, spacers and reagents for gel preparation (the agarose gel is the only yes agarose).
The chamber in which such a minigel running costs, lysozyme so around 1000 EUR. The voltage source costs again so about 250 EUR IIRC. Then there are the consumables and the protein standard, besides you can also buy buffers, etc..
When quite cheap providers lysozyme Roth the whole thing costs 730 plus the complete power supply, about 500 : July http://www.carlroth.com/...ang=de-de&market=DE lysozyme Joe Dramiga 29, 2011 8:21 Replies | Permalink
several lysozyme dyes I understand sometimes three dyes, the sample buffer so, bromophenol blue, xylene cyanol, Orange G. The pH changes yes