The more basic the gradient the unsharper the bands (Peter Reiter, Gelita, Eberbach, Germany)
SDS of basic proteins and peptides
Basic proteins and peptides in SDS. Not good! (Peter Reiter, Gelita, Eberbach, Germany)
Basic peptides don’t like to be driven to their isoelectric points! What they like is to have their maximal positive charges. They also have no affinity to the negatively charged SDS-molecule. So they should be separated in a native cathodal electrophoresis. An acidic buffer will do this in a perfect way.
SDS of basic peptides
Basic peptides don’t like SDS (Peter Reiter, Gelita, Eberbach, Germany)
Native cathodal electrophoresis: Basic peptides want to be separated in an acidic buffer. Here they are charged (+)!
In native electrophoresis you will have no relation to mol-weight! Double dimensional electrophoresis shows this. First dimension = native cathodal electrophoresis Second dimension = SDS-electrophoresis
<------------- cathodal native electrophoresis
September 21, 2020
Native cathodal electrophoresis: Basic peptides / proteines of E.coli
Acidic buffer = cathodal electrophoresis
I I I I I I I I I I I
I I I I I I I I I I I I I I I I
If SDS shows no good results as second dimension: Double Native Electrophoresis First dimension = IPG-strip pH 7-11, 11 cm Second dimension = cathodal native electrophoresis Visualization: Hot Coomassie or Semi-Colloidal Coomassie
<------------- IPG-strip 7-11 ----------->
Basic peptides / proteins of E.coli in double native electrophoresis Molweights are not relative to their migration speeds.