I expressed a recombination protein in Pichia pastoris and got pure protein after purified from Ni-column. I confirmed my pure protein was only one band in SDS-PAGE, however, it was degraded after storing in few days. The molecular weight of the degraded protein was decrease about 10kDa. It is interesting that degraded protein had better activity than undergrad one. According
to this result, is there any thing that can degrades my pure protein or my protein has auto-degradation? In anyone can help me found out these question?
My protein is glycohydrolase, not protease.