TAE buffer is added to maintain the pH of the DNA solution to neutral. Electrolysis can lead to electrolysis of water molecules and thereby release of H+ ions. These H+ ions can interact with the negatively charged DNA, neutralizing it and therefore stopping electrophoretic movement of DNA.
TAE is a buffer solution which contains a mixture of Tris base Acetic acid and EDTA
it is used as a buffer to adjust pH to protect DNA from being hydrolyzed
it also chelates any metal ions in the gel and thus inactivates any enzyme that can lead to DNA degradation (since most DNA degradation enzymes require metal ions to function so chelating these ions will prevent these enzymes from functioning)
Tris is a strong base (T), acetate (A) is an acid, and the combination (TA) is a buffer at slightly alcaline range (pH 8-8.5). Under these slightly alcaline conditions, DNA is best protected against hydrolysis. EDTA is a chelating agent that sequesters divalent ions, in particular magnesium ions. This is good because the enzyme DNAse requires Magnesium ions for its activity. So this is all to keep the DNA safe whilst running on a gel.
The combination of the buffer TA and EDTA (TAE) is used for agarose gel electrophoresis of large DNA fragments (2kb or larger) because it is thought to be easier to extract large DNA fragments when you use acetate. A more popular buffer for DNA agarose electrophoresis is TBE (acetic acid is replaced by boric acid). TBE is a better buffer, and most people use this. TBE buffered gels generally yield sharper DNA bands compared to TAE when the framents are smaller than 2kb.
TAE or TBE both are buffer containing EDTA, Buffer maintains the pH of medium by which nucleic acid can run smoothly. EDTA is chelating agent bind with divalent cations specially Mg, which is required for action of DNase enzyme. In absence of free Mg++ DNase is inactive, so it can not degrade DNA.
Jürgen Denecke , acetate isn't the acid, but the acetic acid you ad afterwards is the acid ( https://www.quora.com/What-happens-when-sodium-acetate-dissolves-in-water ). Sodium acetate in fact is slightly alkaline.
Jacob Zubek, yes I meant the acid of course, and the resulting salt is Tris-acetate (TA), which is slightly alcaline. TAE does not contain sodium acetate. The point of answering the question was to explain the alcaline buffering function and the chelating function to provide a stable environment for DNA in aqueous solution, and to outline the differences between TAE and TBE.
TAE which composed of a mixture Tris base Acetic acid and EDTA works as a buffer during gel electrophoresis which maintain PH of the medium to led nucleic acids run through the gel smoothly. Moreover, it provides the ions that carry a current and inactivates DNase due to presence of EDTA.
TAE is mainly a buffer which made of Tris base, acetic acid and EDTA. This buffer has a crucial role in maintaining the pH of medium by which nucleic acid can run smoothly. Moreover, it uses for agarose gel electrophoresis of large DNA fragments (2kb or larger) because it is thought to be easier to extract large DNA fragments when you use acetate.
TAE which composed of a mixture Tris base Acetic acid and EDTA works as a buffer during gel electrophoresis which maintain PH of the medium to led nucleic acids run through the gel smoothly. Moreover, it provides the ions that carry a current and inactivates DNase due to presence of EDTA.