Hi Bill:
Thanks for the prompt reply. I will try purifying the protein without
mercaptoethanol.
Wataru
On 2009/05/13, at 11:42, William G. Scott wrote:
> HI Wataru:
>
> I think it makes an R-S-S-R' bond, so the disulfide will prevent the
> heavy atom from binding, unless exchange is rapid.
>
> I hope all is well.
>
> Bill
>
>
> On May 12, 2009, at 7:17 PM, Wataru Kagawa wrote:
>
>> Hi.
>>
>> We are trying to prepare heavy atom derivatives of a protein in
>> which a surface residue was mutated to cysteine. Mass spectrometry
>> of the purified cysteine mutant showed an additional peak with a
>> molecular mass that correspond to a mercaptoethanol-bound cysteine
>> mutant. I am wondering whether the bound mercaptoethanol prevents
>> the heavy atom from binding to the cysteine residue.
>>
>> Any information would be greatly appreciated.
>>
>> Wataru Kagawa
>
|