Re: [ccp4bb] crystallisation

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Subject: Re: crystallisation
From: Kay Diederichs kay {- dot -} diederichs {- at -} UNI-KONSTANZ {- dot -} DE
Date: 2008-06-03

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Subject: Crystals grown directly on loop?
From: Jacob Keller j-keller2 {- at -} MD {- dot -} NORTHWESTERN {- dot -} EDU
Date: 2008-06-03

Subject: Re: crystallisation
From: Phoebe Rice price {- at -} UCHICAGO {- dot -} EDU
Date: 2008-06-03

If you have high [DTT] in your buffer, you might be
catalyzing the addition of dimethyl arsenic (from the
cacodylate) to some of your cysteines?
Also, 10% glyercol sounds quite low for reproducibly good
freezing (at least in my experience).
Phoebe

---- Original message ----
>Date: Mon, 2 Jun 2008 17:04:38 +0100
>From: sajid akthar
>Subject: [ccp4bb] crystallisation
>To: CCP4BB@JISCMAIL.AC.UK
>
>
>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/
>________________
>DSCN0003.JPG (720k bytes)
Phoebe A. Rice
Assoc. Prof., Dept. of Biochemistry & Molecular Biology
The University of Chicago
phone 773 834 1723
http://bmb.bsd.uchicago.edu/Faculty_and_Research/01_Faculty/01_Faculty_Alphabetically.php?faculty_id=123

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Please do take a
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CCP4bb <-- 2008 <-- June 2008 <-- 03 June 2008

Previous message:
Subject: Re: crystallisation
From: Kay Diederichs kay {- dot -} diederichs {- at -} UNI-KONSTANZ {- dot -} DE
Date: 2008-06-03

Next message:
Subject: Crystals grown directly on loop?
From: Jacob Keller j-keller2 {- at -} MD {- dot -} NORTHWESTERN {- dot -} EDU
Date: 2008-06-03