I also have seen similar. I was thinking it was potentially some kind
of radiation damage? Is there a good paper which examines what
chemistries are seen in rad damage?
Jacob
On Thu, Nov 17, 2011 at 5:39 AM, Eleanor Dodson <[log in to unmask]> wrote:
> Yes - I have seen something similar at a lower resolution, but very ugly! I
> tried to model it as a solvent molecule - possible but not too convincing..
>
> Cl should give an anomalous signal - try a DANO map and see what it shows..
> Eleanor
>
>
> On 11/17/2011 11:09 AM, Dean Derbyshire wrote:
>>
>> Hi all,
>> Has anyone observed 'odd' arginine residues, missing the NH1 atom; and
>> possibly related.. very close Chlorine-arginine (NH1 again) distances.
>>
>> I have a 1.3Ĺ structure and am having trouble getting my head around some
>> very odd density features.
>>
>> I have 2 molecules in the assym. with the equivalent arg residues showing
>> the same odd feature.
>> Seems to be a chlorine binding site - typical mix of hydrophobic and
>> proton rich side chains - but, the NH1 of the particular arginine residue
>> concerned (as I say in both NCS copies) seems to have only 50% occupancy and
>> the chlorine appears to have a 2nd distinct position closer to the arginine,
>> such that if the NH1 atom were present it would be only 2Ĺ away!
>>
>> ?
>>
>> Cheers in advance
>>
>> Dean
>>
>>
>>
>
--
*******************************************
Jacob Pearson Keller
Northwestern University
Medical Scientist Training Program
email: [log in to unmask]
*******************************************
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