So, if you are bored and have nothing else to do (which is how we all
are at times; kidding), can you set up a control experiment with
everything in the crystal dip except protein (so buffer and whatever)?
I know protein plays a role in the process, but I have done this before
when I had suspect conditions, and it did show that my buffer formed
crystals in that situation.
Sometimes it helps. But I am one that never throws a crystal away, and
always just puts it in a beam before saying it's salt. Protein crystals
are too precious to rule out by over thinking.
Good luck
Dave
On 2/8/2013 9:13 AM, Edward A. Berry wrote:
> Raji Edayathumangalam wrote:
>> (3) Inconclusive "no diffraction" situation, which could indicate a
>> million things including the possibility that your
>> cryoprotectant was sub-optimal for data collection done using flash
>> cryocooled/flash frozen crystals in a stream of
>> gaseous nitrogen.
>
> But before throwing it in this category, be sure to take a wide-angle
> oscillation, as reciprocal space is sparsely populated with small
> unit cell crystals and you might miss spots altogether in a
> 1 degree oscillation.
>
> I like to take a 5-sec 180* oscillation which gives plenty of
> spots in a nice pattern for a salt crystal, and I suppose
> records enough spacings to positively identify the mineral
> if anyone cared to tak the time.
> eab
>>
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