Do proteins break up on SDS PAGE treatment?

Student mucineer at
Fri Nov 17 11:20:15 EST 2000

Do proteins break up by heating with SDS buffer at 70 degrees for 10
minutes? I found that when I ran a non-reduced SDS PAGE gel on a purified
protein (IgG purified from a protein column), although the vast majority of
the product is at the right size, there are some faint bands scattered
below. I am quite sure that they are not contaminants because when I ran a
reduced gel, they weren't there (just one very faint band as opposed to 4 or
5 in the non-reduced gel), yet they both came from the same sample!

I am just wondering if the protein was cleaved somehow in the process. Is
this normal?


More information about the Methods mailing list