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Re: [ccp4bb] crystallisation and mosaicity
 

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CCP4bb <-- 2008 <-- June 2008 <-- 03 June 2008
Previous message:
Subject: Re: crystallisation
From: Mark Brooks mark {- dot -} x {- dot -} brooks {- at -} GMAIL {- dot -} COM
Date: 2008-06-03 		Next message:
Subject: Re: crystallisation and mosaicity
From: Paul Paukstelis paul {- at -} ICMB {- dot -} UTEXAS {- dot -} EDU
Date: 2008-06-03


Subject: Re: crystallisation and mosaicity
From: Daniel Pomeranz Krummel dapk {- at -} MRC-LMB {- dot -} CAM {- dot -} AC {- dot -} UK
Date: 2008-06-03
Dear Sajid,

I have observed a consistent reduction in mosaicity (from approx. 0.95 to
0.45) for one case by freezing the crystals in a cryostream (N2 vapour) as
opposed to submerging in liquid nitrogen.

Have others observed this?

Daniel
>
> 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/

CCP4bb navigation

CCP4bb <-- 2008 <-- June 2008 <-- 03 June 2008
Previous message:
Subject: Re: crystallisation
From: Mark Brooks mark {- dot -} x {- dot -} brooks {- at -} GMAIL {- dot -} COM
Date: 2008-06-03 		Next message:
Subject: Re: crystallisation and mosaicity
From: Paul Paukstelis paul {- at -} ICMB {- dot -} UTEXAS {- dot -} EDU
Date: 2008-06-03


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