S/T formylation by formic acid can be extensive and
should probably be expected.
steve
On Fri, 28 Sep 2007, [log in to unmask] wrote:
> Can you show the map?
>
> Anthony
>
>
>> Dear all
>>
>> I am refining a peptide structure with an N-terminal throenine.
>> However, the density map of the N-terminal part looks strange,
>> the first throenine does not fit in well while the second valine
>> fits very well. It seems that this throenine was modified somehow
>> during protein production. The peptide was expressed in E.Coli
>> and cleavaged by Formic Acid and Cyanogen Bromide, then
>> purified by HPLC and lyophilized.
>>
>> Does anyone have similar experience of a modified N-terminal
>> throenine? If so, please kindly point to me a reference.
>>
>> Thank you.
>>
>> Jie Liu
>>
>
--
Steve Kaiser
Kopito Lab
Stanford University
Lokey Laboratories, Room 154
337 Campus Loop Drive
Stanford CA, 94305
tel:650-723-7588
fax:650-723-0155
mail: [log in to unmask]
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