Re: [ccp4bb] Cryoprotectant for protein-DNA complex crystal

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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

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Subject: Re: Semet in non-auxotrophic strains
From: Cynthia Kinsland clk10 {- at -} CORNELL {- dot -} EDU
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Subject: Re: Semet in non-auxotrophic strains
From: Jacob Keller j-keller2 {- at -} MD {- dot -} NORTHWESTERN {- dot -} EDU
Date: 2008-11-03

Subject: Re: Cryoprotectant for protein-DNA complex crystal
From: Phoebe Rice price {- at -} UCHICAGO {- dot -} EDU
Date: 2008-11-03

I think we still have better luck with longer, slower, more
gentle soaks - but its crystal-dependent.
Try raising the [PEG] at the same time as you raise the
[glycerol].
Phoebe

---- Original message ----
>Date: Fri, 31 Oct 2008 18:57:53 -0400
>From: Artem Evdokimov
>Subject: Re: [ccp4bb] Cryoprotectant for protein-DNA complex
crystal
>To: CCP4BB@JISCMAIL.AC.UK
>
>Why soak for a whole minute? A single pass through cryo is
usually enough,
>and that takes a couple of seconds with the right set-up...
>
>You could try oil - if you're lucky it solves your issues.
Note that not all
>oils are the same, and many people succeed with blended
compositions rather
>than pure stuff.
>
>Finally, you could always try my humble recipe:
>
>http://www.xtals.org/crystal_cryo.pdf
>
>Good luck,
>
>Artem
>
>-----Original Message-----
>From: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] On
Behalf Of E
>rajakumar
>Sent: Friday, October 31, 2008 5:22 PM
>To: CCP4BB@JISCMAIL.AC.UK
>Subject: [ccp4bb] Cryoprotectant for protein-DNA complex crystal
>
>Dear All
>I am working on protein-DNA complex crystals for data
>collection. These crystals are grown in 15-20 % of
>PEG3350 or PEG4000 with pH of 6 to 7. When I soak the
>crystals more than a minute in the cryo solution
>(15-20% of Glycerol or ethylenglycol + reservoir) the
>resolution of diffraction is becoming weak (reducing
>to 6.0 A from 4.5 A) and also the spots are getting
>spread (increase in mosaicity). Appears that Glycerol
>or Ethylene glycol not good cryoprotectants in this
>case. Is there any study on effect of cryoprotectant
>on protein-DNA complex crystal and protein-DNA complex
>dissociation? I also want to know which type
>(organics, oils, polyols, sugars, polymers.) of
>cryoprotectant is most preferred in protein-DNA
>complex crystal.
>Thanking you in advance
>Rajakumara
>
>
>E. Rajakumara
>Postdoctoral Fellow
> Strcutural Biology Program
> Memorial Sloan-Kettering Cancer Center
> New York-10021
> NY
> 001 212 639 7986 (Lab)
> 001 917 674 6266 (Mobile)
>
>
>
> Get your new Email address!
>Grab the Email name you've always wanted before someone else
does!
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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

RNA is really nifty
DNA is over fifty
We have put them
both in one book
Please do take a
really good look
http://www.rsc.org/shop/books/2008/9780854042722.asp

CCP4bb navigation

CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Re: Semet in non-auxotrophic strains
From: Cynthia Kinsland clk10 {- at -} CORNELL {- dot -} EDU
Date: 2008-11-03

Next message:
Subject: Re: Semet in non-auxotrophic strains
From: Jacob Keller j-keller2 {- at -} MD {- dot -} NORTHWESTERN {- dot -} EDU
Date: 2008-11-03