Dear All
My protein size is ~30kD and crystallizes with
19%Peg3350, 0.2M Nacl, and 0.1M Na Cacodylate buffer.
Please refer the attached crystal image with this. The
crystal looks like good enough for home source. These
crystals appears in 4-5 days at room temp.
Sometimes I'm getting crystals like this, but very few
in 24 well tray. Most of the time, I found the drop
contains needles. If I reduce the precipitant little
bit, I wont find any change in the drop even after
long time. Changing pH (or temp)of the buffer does not
help me any better. The crystal appears only around
5.5pH.
The problem is mosaicity. This crystal diffracted in
home source upto 3.2A and the mosaicity is 2.5degree.
Almost all the good crystal like this having same
mosaicity.
Good cryo condition so far that I found was
10%Glycerol with mother liquor. Other conditions
weekens the diffraction quality or increase mosaicity.
In many crystal I could see some crack in the middle
of the crystal, it looks like twin crystal. Or the
crystal appears with some sattelite crystals.
Can anyone suggest me some good way to overcome these
problems.
Thankz
Sajid
From Chandigarh to Chennai - find friends all over India. Go to http://in.promos.yahoo.com/groups/citygroups/
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