Hi,
First, it's very much a crystallographic question. Second, the success or failure in soaking in ligands/cofactors depends quite often also to the crystal packing. Some packing forms (and the spacegroups that go with it) will tolerate the soaking even if it's accompanied with a conformational change, whereas others won't (like the spacegroup you currently have). So you could try, among the other good suggestions that you were given, more crystallization conditions, perhaps you might get lucky and come across crystals in a different spacegroup which will behave more nicely vis-a-vis soaking.
Good luck,
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 Dianfan Li [[log in to unmask]]
Sent: Wednesday, February 01, 2012 9:17 PM
To: [log in to unmask]
Subject: [ccp4bb] Soaking Kinase Crystals with ATP analogues
Dear all,
Sorry about a non-crystallographic question here.
I am working on a kinase and would like to get an ATP analogue into
the crystals. When soaked with AMP-PCP, the kinase crystals crack in
about 15 min at 4 C.
I could try other analogues like AMP-PNP etc, but those would probably
behavour in a same way as AMP-PCP. Is it a good idea of trying quick
soaks at high concentrations of AMP-PCP? Co-crystallization is another
option I have but AMP-PCP is a substrate of the kinase (with low
rate).
What are other ways of getting ATP analogues into a crystal?
Thanks for suggestions,
Dianfan
Dianfan Li, PhD
College of Biochemistry and Immunology
Trinity College Dublin
Dublin, Ireland.
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