In article <genecutl-310194130016 at kos2mac17.berkeley.edu> genecutl at mendel.berkeley.edu (gc) writes:
>>... Regardless of the initial amount of this higher
>form, it invariably increases over time, during the purification and
>especially during storage afterwords (at 4 degrees). The abundance of
>the mystery band increases until it is roughly 50% of the total protein.
>We've done some mass spec on the mixture and see only one predominant
>mass, with some minor oxidation products (not enough to account for the
>mystery band).
>> Any ideas?
How about a conformational isomer, due to, say, oxidation of disulphide
bridges. Do you have enough DTT/betamercaptoethanol in your denaturing mix?
Robin Walters. Robert Hill Institute, Sheffield UK.
A fact is an opinion that everyone agrees with.