Mystery of SDS gel, working with the protein GB1 (T2Q mutation) - (Mar/31/2015 )
a couple of possibilities:
aggregation and decomposition
concentration of contaminants
Is there a different kind of gel that could prevent the protein from aggregation and decomposition? native gel maybe?
decomposition would occur during handling.
aggregation can occur during handling and/or during heat treatment with sds sample buffer. if it is occurring during the heat treatment then you can incubate at 60-70C instead of 95-100C.
native page will not reduce either and may actually increase aggregation.