Hi all,
yesterday i have tried annealing, no significant improvement.
Thank you so much for all those suggestions.
Summary:
1. check diffraction on RT.
2. dehydrate crystal, many methods
3. try annealing
4. grow crystal in presence of cryo
5. try smaller crystal, sometimes small crystal is
Hi Fengxia-
How about increasing the PEG% so you don't have to add as much other
cryoprotectant?
Also, have you tried annealing the crystals? I've had success with this when
I've had samples diffract similarly. The simplest way is by blocking the
cryostream for 2-3 seconds (repeat 1-2 times) and
Fengxia,
From the images it is clear that the degree of smearing is variable. From
this you can
deduce that you should be able to get sharp images by finding better
cryo-conditions.
There is no magic involved. Your crystallization conditions have little
precipitant
and a lot of water.
Fengxia,
To me the diffraction appears as if the crystals did not freeze well.
So the best option seems to be annealing (as already suggested) or to
try different cryo-protectants.
Did you perform a room-temperature mount? If so, were the spots nice
and round (suggesting the cryo is the cause of
loops with care -
maybe go with litholoops?
Martyn
Martyn Symmons
MRC-MBU
Cambridge
- Original Message
From: Kelly Daughtry kddau...@bu.edu
To: CCP4BB@JISCMAIL.AC.UK
Sent: Thursday, 21 January, 2010 14:27:58
Subject: Re: [ccp4bb] smeared spot in diffraction
Fengxia,
To me
In addition to the good suggestions already posted, I also suggest:
1. Exploring how your cryoprotection is done in addition to screening
chemical conditions. For example, you may want to test longer
equilibration in cryoprotectant, stepwise increase in cryoprotect.,
very fast swish through
