Have seen two or more crystal forms on occasion over the years. Actually the first protein structure I did independently ended up having two forms in the same drop. Both diffracted decently. Also have seen where one form diffracted much better then the other, usually the ugly looking crystal if ones nice and the other looks ugly.
Len
Leonard M. Thomas Ph.D.
Macromolecular Crystallography Laboratory
Price Family Foundation Institute of Structural Biology
Department of Chemistry and Biochemistry
University of Oklahoma
Stephenson Life Sciences Research Center
101 Stephenson Parkway
Norman, OK 73019
405-325-1126
[log in to unmask]
http://barlywine.chem.ou.edu
http://structuralbiology.ou.edu
________________________________________
From: CCP4 bulletin board <[log in to unmask]> on behalf of Francis Reyes <[log in to unmask]>
Sent: Friday, June 24, 2016 8:37:16 AM
To: [log in to unmask]
Subject: Re: [ccp4bb] Is it very unusual to find two or more crystal forms in a crystallization drop?
How about same morphology, same space group, same unit cell parameters but different intensities?
I refer to a previous discussion on the CCP4BB from James Holton regarding the non isomorphism of tetragonal lysozyme due to dehydration.
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I think there's anecdotal evidence showing non isomorphous crystals (at the intensity level) from the same drop of lysozyme crystals... that depended on how quickly one fished crystals out of the drop (dehydration).
Very annoying if you're trying to collect isomorphous crystals.
F
On Jun 24, 2016, at 8:15 AM, Boaz Shaanan <[log in to unmask]> wrote:
> Hi,
>
> We have also come across crystals grown from the same drop that had the same morphology and space group, monoclinic P2(1), but with a different b axis (sufficiently different to make the two forms non-isomorphous).
>
> Cheers,
>
> Boaz
>
>
>
> Boaz Shaanan, Ph.D.
> Dept. of Life Sciences
> Ben-Gurion University of the Negev
> Beer-Sheva 84105
> Israel
>
> E-mail: [log in to unmask]
> Phone: 972-8-647-2220 Skype: boaz.shaanan
> Fax: 972-8-647-2992 or 972-8-646-1710
>
>
>
>
> From: CCP4 bulletin board [[log in to unmask]] on behalf of Murpholino Peligro [[log in to unmask]]
> Sent: Friday, June 24, 2016 11:21 AM
> To: [log in to unmask]
> Subject: [ccp4bb] Is it very unusual to find two or more crystal forms in a crystallization drop?
>
> Hi everybody.
> I just was curious ....
> How often it is to find two or more crystalline forms in a single crystallization drop?
> Is it very common or is it way to rare?
>
> Thanks for your answers
> MP
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